Science

Press Release: Global Warming Expected to Further Degrade Coral Reef Systems

For Immediate Release:
February 13, 2004
                                                             
Contact:  Katie Mandes
(703) 919-2293

Global Warming and Coral Reefs

Global Warming Expected to Further Degrade Coral Reef Systems

 
Washington, DC — Coral reefs have the highest biodiversity of any marine ecosystem, providing important ecosystem services and direct economic benefits to the large and growing human populations in low-latitude coastal zones.  One recent estimate valued the annual net economic benefits of the world’s coral reefs at $30 billion. But human activities including development in coastal areas, over-fishing, and pollution have contributed to a global loss approaching 25 percent of these valuable ecosystems.  Global warming is expected to further contribute to coral reef degradation in the decades ahead.  

A new Pew Center on Global Climate Change report, Coral Reefs & Global Climate Change: Potential Contributions of Climate Change to Stresses on Coral Reef Ecosystems, authored by Drs. Robert W. Buddemeier, Joan A. Kleypas, and Richard B. Aronson, outlines the likely impacts of climate change and global warming over the next century to coral reef systems both in U.S. waters and around the world. The report reviews the published literature in an effort to analyze the current state of knowledge regarding coral reef communities and the potential contribution of future climate change to coral reef degradation and loss.

The report concludes that recent global increases in reef ecosystem degradation and mortality (the “coral reef crisis”) are exceeding the adaptive capacity of coral reef organisms and communities.  The severity of this crisis will only intensify with future changes in the global climate.    

“Coral reefs are striking, complex, and important features of the marine environment,” said Eileen Claussen, President of the Pew Center. “If we fail to act, the destruction of these rare and important ecosystems will continue unabated, threatening one of our world’s most precious natural resources.” 

Other major findings from the report include: 

Climate and localized, nonclimate stresses interact, often synergistically, to affect the health and sustainability of coral reef ecosystems.  Increases in ocean temperature contribute to coral bleaching episodes that cause coral mortality and stress, while future increases in atmospheric carbon dioxide may limit coral growth.  In addition to their direct effects, these stresses also act to degrade coral reefs by increasing their susceptibility to pollution, over-fishing, predation, and disease.  

Coral reef alteration, degradation, and loss will continue for the foreseeable future, especially in those areas already showing evidence of systemic stress.  There is no doubt that continued global warming will cause further degradation of coral reef communities.

The effects of global warming on global coral reef ecosystems will vary from one region to another.  Although climate change has the potential to yield some benefits for certain coral species in specific regions, such as the expansion of their geographic ranges to higher latitudes, most of the effects of climate change will be harmful rather than beneficial.   

While the net effects of climate change on coral reefs will be negative, coral reef organisms and communities are not necessarily doomed to total extinction.  The diversity of existing coral species, the acknowledged adaptation potential of reef organisms, the spatial and temporal variations in climate change, and the potential for human management and protection of coral reef ecosystems all provide scope for survival. 

Multiple environmental management strategies, from local to global, will be necessary to ensure the long-term sustainability of the world’s coral reef ecosystems. Efforts to reduce emissions of greenhouse gases that contribute to global warming can reduce the risk of future bleaching events and moderate changes in ocean chemistry.  Marine protected areas will protect coral reefs from nonclimate stresses and enable coral reefs to better adapt to the effects of global climate change.  

Part of “Impacts” Series:

Coral Reefs & Global Climate Change: Potential Contributions of Climate Change to Stresses on Coral Reef Ecosystems, was prepared for the Pew Center by a team of U.S. experts on coral reef ecosystems including Drs. Robert W. Buddemeier, Kansas Geological Survey; Joan A. Kleypas, National Center for Atmospheric Research; and Richard B. Aronson, Dauphin Island Sea Lab.  It is the tenth in a series of Pew Center reports examining the potential impacts of climate change on the U.S. environment.  Other Pew Center reports focus on domestic and international policy issues, global warming solutions, and the economics of global warming. 

A complete copy of this report and other Pew Center reports can be accessed from the Pew Center’s website: www.c2es.org.

###

The Pew Center was established in May 1998 by The Pew Charitable Trusts, one of the United States’ largest philanthropies and an influential voice in efforts to improve the quality of the environment.  The Pew Center is an independent, non-profit, and non-partisan organization dedicated to providing credible information, straight answers, and innovative solutions in the effort to address global climate change.  The Pew Center is led by Eileen Claussen, the former U.S. Assistant Secretary of State for Oceans and International Environmental and Scientific Affairs.

Coral Reefs & Global Climate Change

Coral Reefs Small Report Cover

Coral Reefs & Global Climate Change: Potential Contributions of Climate
Change to Stresses on Coral Reef Ecosystems


Prepared for the Pew Center on Global Climate Change
February 2004

By:
Robert W. Buddemeier, Kansas Geological Survery
Joan A. Kleypas, National Center for Atmospheric Research
Richard B. Aronson, Dauphin Island Sea Lab


Press Release

Download Entire Report (pdf)

Joan A. Kleypas
Richard B. Aronson
Robert W. Buddemeier
0

The Science of Climate Change: Global and U.S. Perspectives

The Science of Climate Change: Global and U.S. Perspectives

By:
Tom M. L. Wigley, National Center For Atmospheric Research

Press Release

Download Entire Report (pdf)

Download Report (ZIP file)

This report is available for download only.

Basic Science on climate change:

  • Projections of future climate change suggest a global temperature increase of 1 to 6°C (2 to 10°F) from 1990 to 2100, with warming in most of the United States expected to be even higher.
  • Current scientific research shows that climate change will have major effects on precipitation, evapotranspiration, and runoff — and ultimately on the nation's water supply
  • While the net impacts of a doubling of atmospheric CO2 concentrations on U.S. agriculture as a whole are likely to be small, the impacts are likely to vary considerably from region to region.
  • Climate change will lead to substantial sea-level rise along much of the U.S. coastline, due mostly to thermal expansion of the oceans.
  • The very real possibility exists that warming over this century will jeopardize the integrity of many terrestrial ecosystems and will pose a threat to our nation's biodiversity.

The Wigley report provides more information on how climate is influenced by anthropogenic factors. You may download a pdf of the entire report by clicking on the report cover above, or read portions of the report in html by following the links in the "In This Section" box.

Foreword

 

Eileen Claussen, Executive Director, Pew Center on Global Climate Change

This report on the science of climate change seeks to explain how climate is influenced by anthropogenic factors. Understanding the effect of greenhouse gas concentrations on the atmosphere is key to understanding the potential magnitude of the "greenhouse effect," evaluating possible environmental impacts, and considering policy responses.

A variety of factors determine the rate and magnitude of climate change, including the emissions of greenhouse and aerosol-producing gases, the carbon cycle, the oceans, biosphere, and clouds. As our understanding in each of these areas evolves, it is important that researchers, policy-makers, the press, and the public be kept informed since these developments affect our understanding of the seriousness and complexity of this issue.

As part of the Pew Center's series examining the potential impacts of higher atmospheric concentrations of greenhouse gases on the United States, this paper by the distinguished climate scientist Tom M.L. Wigley, senior scientist with the National Center for Atmospheric Research, addresses what is known and not known about the science of climate change. Its publication comes in an interim period between assessments of the science by the Intergovernmental Panel on Climate Change (which published its second assessment in 1996 and will publish its third assessment in 2001). The author uses preliminary estimates of greenhouse gas and sulfur dioxide emissions from the current IPCC review process as well as his own work to supplement previously published research.

The new research suggests the likelihood of slightly larger changes in temperature and sea level rise than projected in the most recent IPCC assessment. The temperature rise is expected to be greater in the U.S. than the average temperature increase across the globe. While changes in precipitation and extreme weather events such as hurricanes and other storms are more difficult to predict, it is possible that the intensity of rain and hurricane events could increase. Uncertainties in predicting the direction and magnitude of these changes make it difficult to predict the impacts of climate change. However, even small changes in climate can lead to effects that are far from trivial.

While the analysis presented is the work of one author, this report has been subject to extensive peer review. The Pew Center and the author are indebted to many scientists and organizations for their constructive comments on previous drafts of this paper or sections of this paper. Their comments have helped improve the text substantially, and so, while the opinions expressed in this report are solely those of the author, we gratefully acknowledge their input: E. Barron, B. Felzer, C. Hakkarinen, A. Henderson-Sellers, M. Hulme, M. MacCracken, M. McFarland, J. Mahlman, G. Meehl, N. Nakicenovic, B.D. Santer, M.E. Schlesinger, K.P. Shine, J.B. Smith, and S.J. Smith. The A1, A2, B1, and B2 scenarios developed in the current IPCC working group process have been used with the kind permission of their producers, represented by T. Morita, A. Sankovski, B. deVries, and N. Nakicenovic. D. Viner of the Climate Impacts LINK Project (UK Dept. of the Environment, Regions and Transport contract EPG1/1/68) supplied the HadCM2 data on behalf of the Hadley Centre and UK Meteorological Office. In addition, the Pew Center would like to acknowledge and thank Joel Smith and Brian Hurd of Stratus Consulting for their management of this Environmental Impacts series.

Executive Summary

 

The average surface temperature of the globe has warmed appreciably since the late 1800s, by about 0.6°C. Since this warming cannot be adequately explained by natural phenomena such as increased solar activity, human-induced increases in greenhouse-gas concentrations appear to be at least partly responsible. In addition to the warming effect of greenhouse-gas increases, however, changes in temperature over the past century are likely to have been significantly influenced by the cooling effect associated with changes in the sulfate aerosol loading of the atmosphere, arising from fossil-fuel-derived sulfur dioxide (SO2) emissions. When greenhouse-gas, sulfate aerosol, and solar influences are considered together, observed climate changes are consistent with model predictions.

Projections of future global-mean temperature and sea level change made by the Intergovernmental Panel on Climate Change (IPCC) in its 1996 Second Assessment Report used emissions scenarios developed in 1992. Preliminary versions of new emissions scenarios produced by the writing team for the IPCC Special Report on Emissions Scenarios (SRES) are now available. The most important difference between the old (1992) and new (SRES) scenarios is that the new scenarios have much lower emissions of sulfur dioxide. The reduction in sulfur dioxide emissions (and their attendant cooling effects through the production of sulfate aerosols) results in a slight increase in temperature and sea level rise projections from those previously given by the IPCC. If central estimates of model parameters are used, global-mean warming from 1990 to 2100 ranges from 1.9°C to 2.9°C. Sea-level rise estimates over the same period range from 46 to 58 cm. For temperature and sea level changes over the next few decades, projections are virtually independent of the emissions scenario.

Based on results from a number of climate models, the rate of future warming over the United States is expected to be noticeably faster than the global-mean rate. Future regional-scale precipitation changes are highly uncertain. The only result that is common to all climate models is an increase in winter precipitation in northern latitudes, from the northern Great Plains to the northeastern states. Even in the absence of large precipitation changes, there could still be significant changes in the availability of water for agriculture, human consumption, and industry because of the increased evaporation that should accompany warming. This factor alone would lead to drier summer soil conditions and reduced runoff. The effects of increased evaporation, however, may be partly offset by the direct plant-physiological effect that carbon dioxide (CO2) has in improving plant water-use efficiency and, hence, lowering evapotranspiration rates.

Changes in weather and climate extremes over the United States are certain to occur as the global climate changes. The frequency of extremely hot days is almost certain to increase, and the frequency of frosts should decrease. Changes in the frequency of daily precipitation extremes are highly uncertain, although there is evidence for an increase in the frequency of wet extremes. For hurricanes and tropical storms, the evidence suggests that there could be small increases in their windspeeds. It is also likely that future such storms will be accompanied by larger rainfall amounts. While there is no credible model-based information on changes in the number of hurricanes and tropical storms per year worldwide, there is empirical evidence that suggests that a small increase in frequency is possible in the North Atlantic region. For all extreme events, however, it is unlikely that the projected changes will become evident in a statistically convincing way for many decades, with the exception of temperature extremes, which should become evident sooner.

About the Author

 

Tom M.L. Wigley

Tom M.L. Wigley (B.Sc., Ph.D.), formerly Director of the Climatic Research Unit, University of East Anglia, Norwich, U.K., currently holds a Senior Scientist position with the National Center for Atmospheric Research, Boulder, CO. One of the world's foremost scientists in the area of climate change, he has published in diverse aspects of the broad field of climatology. His main interests are in carbon cycle modeling, projections of future climate and sea-level change, and interpretation of past climate change particularly with a view to detecting anthropogenic influences. Recently, he has concentrated on facets of the global warming problem, and has contributed on many occasions to Intergovernmental Panel on Climate Change (IPCC) reports and assessments.

 

Tom M. L. Wigley
0

Forests & Global Climate Change

forestrycover

Forests & Global Climate Change: Potential Impacts on U.S. Forest Resources

Prepared for the Pew Center on Global Climate Change
February 2003

By:
Herman Shugart, University of Virginia
Roger Sedjo, Resources for the Future
Brent Sohngen, The Ohio State University

Press Release

Download Entire Report (pdf)

Foreword

Eileen Claussen, President, Pew Center on Global Climate Change

Approximately one-third of U.S. lands are covered by forests, which makes forest ecosystems prominent natural resources that contribute to biodiversity, water quality, carbon storage, and recreation. Forests also play a significant role in the U.S. economy, and forestry or forestry-related enterprises are the dominant industries in many U.S. communities. Human-induced climate change over the next century is projected to change temperature and precipitation, factors that are critical to the distribution and abundance of tree species.

Forests and Global Climate Change is the ninth in a series of Pew Center reports examining the potential impacts of climate change on our environment and health. A previous report in this series addressed the risks to terrestrial ecosystems posed by climate change. This report details the likely ecological and economic impacts of climate change over the next century on the U.S. forestry sector. Key findings include:

Forest location, composition, and productivity will be altered by changes in temperature and precipitation. Climate change is virtually certain to drive the migration of tree species, resulting in changes in the geographic distribution of forest types and new combinations of species within forests. Generally, tree species are expected to shift northward or to higher altitudes. In addition, climate change is likely to alter forest productivity depending upon location, tree species, water availability, and the effects of carbon dioxide (CO2) fertilization.

Changes in forest disturbance regimes, such as fire or disease, could further affect the future of U.S. forests and the market for forest products. Increased temperatures could increase fire risk in areas that experience increased aridity, and climate change could promote the proliferation of diseases and pests that attack tree species. Such disturbances may be detrimental to forests themselves, but may have a lesser impact at the market level due to salvage operations that harvest timber from dying forests.

U.S. economic impacts will vary regionally. Overall, economic studies indicate that the net impacts of climate change on the forestry sector will be small, ranging from slightly negative to positive impacts; however, gains and losses will not be distributed evenly throughout the United States. The Southeast, which is currently a dominant region for forestry, is likely to experience net losses, as tree species migrate northward and tree productivity declines. Meanwhile, the North is likely to benefit from tree migration and longer growing seasons.

As a managed resource, the implications of climate change for the forestry sector are largely dependent upon the actions taken to adapt to climate change. The United States has vast forest resources and currently consumes less timber than grows within the country each year. If professional foresters take proactive measures to substitute thriving tree species for failing species, to relocate forestry industry to productive regions, and to salvage trees during dieback, the sector may minimize the negative economic consequences of climate change.

A number of challenges currently limit our understanding of the effects of climate change on forestry. Existing projections for future changes in temperature and precipitation span a broad range, making it difficult to predict the future climate that forests will experience, particularly at the regional level. The ecological models used to relate forest distribution and productivity to changes in climate introduce additional uncertainty. Thus, current projections could fail to accurately predict the actual long-term impacts of climate change on the forestry sector.

The authors and the Pew Center gratefully acknowledge the input of Ralph J. Alig, Linda Joyce, G. Cornelis van Kooten, and William H. Schlesinger on this report. The Center would also like to thank Joel Smith of Stratus Consulting for his assistance in the management of this Environmental Impacts Series.

Executive Summary

Climate change is expected to have far-reaching consequences for forests and, subsequently, timber production in the United States. Although studies have shown that forests have adapted to temperature increases of 2-3°C (3.6-5.4°F) in the past, these changes occurred over thousands of years. Current climate predictions suggest that average global mean temperatures could rise 1.5-5.8°C (2.7-10.4°F) over this century alone. Such rapid changes in a relatively short period of time could affect forests significantly. Understanding how climate change will affect future forests and markets, however, is a complex task. Ecological and economic processes are exceptionally complicated, and understanding how integrated ecological and economic systems will respond to changing climate conditions remains a challenge. In spite of a number of remaining uncertainties, this report describes the many important insights into this process discovered over the last 10-20 years of research.

This report explores the potential effects of climate change on both natural and managed forest ecosystems, which differ significantly in their potential responses to climate change. Managed forests, such as forest plantations, receive significant amounts of human intervention in the form of planting, thinning and other management activities. These interventions have the potential to ameliorate the adverse effects of climate change. However, large areas of forest are considered natural and receive minimal direct human management, and thus may be more vulnerable to the effects of climate change. This duality within the forest sector makes it more difficult to state with precision what the overall economic impacts of climate change on forests will be. Further, the ecological changes caused by climate change could have large implications both for non-market attributes (e.g., biodiversity) and for other economic sectors associated with forests (e.g., recreation and water supply). The economic analysis in this report, however, focuses strictly on timber market impacts.

One of the most important ways that researchers discover clues about how forest ecosystems will respond to climate change is to explore the historical record for data regarding the impacts of past climate changes. This record indicates that individual tree species respond to warming either by changing their ranges or by increasing or decreasing their abundance. More recently, researchers have developed sophisticated models to explore how species distributions may change as climate changes. These changes could include increases or decreases in forest area, changes from one forest type to another, or movements of specific species from place to place.

In addition to species migration, it is important to consider how climate change could affect the productivity of forests (i.e., annual growth in forests). Existing studies show both positive and negative impacts on overall productivity, depending on the climate scenario. Further, some locations could experience higher productivity while others experience lower productivity. For example, forests in the southern United States are generally sensitive to the effects of drying, and productivity is more likely to decline there, while productivity is generally predicted to rise in the northern United States in response to low to moderate warming.

Understanding how productivity will change is complicated by an incomplete understanding of the effects of higher atmospheric carbon dioxide (CO2) concentrations on plant growth and ecosystem processes (so-called “carbon fertilization”). Experimental evidence suggests that carbon fertilization is likely to increase individual tree growth. Some evidence also suggests that the CO2 effect makes trees use water more efficiently, thereby making them less vulnerable to drought. Other evidence, however, suggests that the effects of carbon fertilization decline as trees age and at wider spatial scales where forest losses from other processes become important. Unfortunately, most measurements have been made on individual trees in experimental conditions, and not on entire forest ecosystems. In natural forests, and even in managed industrial forests, enhanced growth in trees could be offset by increased natural mortality elsewhere in the system. This is certainly the case for plantation forests where foresters usually predict increased thinning with higher growth in well-stocked stands.

While more precise regional estimates will be made as climate models provide a fuller understanding of regional climate change, and as ecological impacts become clearer, the existing results suggest that timber production could shift northward. Although some shifting will occur throughout most U.S. forests, the shifts would be strongest if the area suitable for southern softwoods expands northward. Hence, southern forests and markets appear most susceptible to climate change, in part because southern species are sensitive to drying effects, and in part because northward migration would erode the comparative advantage for timber production currently enjoyed by southern producers. Southern forests are also the most important economically since they account for well over one-half of U.S. production.

Changes in the frequency and intensity of disturbances like forest fires, pest infestations, and windthrow (i.e., from large storm events) are likely to have large consequences for the structure of both natural and managed forests. Natural forests, in particular, will be heavily influenced by changes in disturbances. Because disturbance has long been an important issue in forest management, managers have a number of tools available for adapting industrial and other managed forests as conditions change. Large-scale disturbances, however, can have substantial effects on markets. For example, although disturbances can cause substantial forest dieback, such ecological damages have the potential to cause short-term increases in timber supply, depressing timber prices for consumers.

As with agriculture, forest landowners have many options for adapting to the types of changes likely to occur with climate change, such as by salvaging dead and dying timber and by shifting to species that are more productive under the new climatic conditions. The long time lags between planting and harvesting trees, however, complicate the decisions for landowners. Adaptation can also occur at the market level, such as changing the types of species used in producing end products. End products are made from a wider variety of species today than 30 years ago; such adaptations help protect the market from large-scale changes in supply.

The following summarizes the current understanding of the potential impacts of climate change on U.S. forests and timber markets over the next century:

1. Tree species generally are expected to migrate northward or to higher altitudes in response to increased temperatures. While species will adapt over time by moving from one region to another, differential rates of change may cause significant differences in the types of natural stands in the future. Rates will depend critically on (a) how fast seeds migrate into new regions that are climatically suitable for a species after a climate change, (b) changes in the spread of insects and disease, (c) the spread of wildfire in different climates, and (d) human interventions to promote species migration.

2. Forest productivity is expected to change, but the changes could be positive or negative. Forests could become more or less productive, depending on how much climate changes (including both temperature and precipitation), how forests respond to higher carbon concentrations in the atmosphere, whether mortality changes, and whether disturbance-induced dieback increases or decreases. Many of these factors are expected to vary from region to region, suggesting that economic impacts are likely to differ among regions in the United States.

3. The effect of additional carbon dioxide in the atmosphere on forested ecosystems (“carbon fertilization”) is complex and uncertain, but it has large implications for understanding how forest productivity will change. Most studies suggest that forest area and productivity will increase if carbon fertilization enhances forest growth, but will decline if carbon fertilization does not occur. Plant-level experiments suggest that carbon fertilization will enhance tree growth, at least for some period of time. Scaling these results up to the ecosystem level is complex, but available studies suggest that carbon fertilization will be limited by competition, disturbance, and nutrient limitations. It is important to continue developing a better understanding of carbon fertilization effects, particularly at the ecosystem scale.

4. Changes in the frequency and severity of forest disturbance, such as storm damage, fires, and pests are likely to affect forest structure and function. The impact on markets, while generally negative, can be ameliorated by salvage. At the market level, salvage associated with disturbances can increase timber supply and reduce prices in the short-term, which benefits consumers. However, increased disturbance and lower prices generally have negative effects on landowners.

5. United States timber markets have low susceptibility to climate change because of the large stock of existing forests, technological change in the timber industry, and the ability to adapt. The United States currently consumes less timber than grows within the country each year, providing a cushion if climate change has short-term impacts on supply. Further, companies already substitute a wide array of species in end products, so that if particular species are negatively affected by climate change, markets can adapt by changing the types of species used in the production of end products. In addition, landowners can assist natural migration of timber by planting southern species in the North.

6. Economic studies have tended to find small negative to positive overall effects on timber production in the United States. While the studies have looked at a wide range of potential climate change effects across species within the United States, the net productivity effects used by the studies have tended to be positive over the long-term. Higher forest productivity translates into increased timber yield, increased timber inventory, increased supply, and lower prices. Lower prices generate overall net benefits, although they primarily benefit consumers at the expense of landowners. Lower forest productivity has the opposite effect.

7. Northern states may gain from climate change if productivity increases and if southern species move north, while southern states may lose production. Producers in southern regions are the most vulnerable to climate change because they have a large share of the nation’s current timber production capital, and the highly productive species in that region are sensitive to potential drying effects. Northern states are generally predicted to gain productivity and market share during climate change.

8. Understanding the economic effects of climate change on timber production is limited by scientific understanding of several key factors that control the response of natural and managed forests to climate change. Additional research is needed to enable ecologists and foresters to develop a more robust understanding of future changes in U.S. climate, ecosystem responses to climate change, the relationship between forest productivity and timber yield, and adaptation options available to foresters. Future clarification of these uncertainties will permit more informed assessments of the economic impacts of climate change to the forestry sector.

Conclusions

Unlike other sectors, such as agriculture, that are almost exclusively comprised of managed systems, forests are comprised of both natural and managed systems. This makes it more difficult to state with precision what the overall economic impacts of climate change on forests will be. Further, understanding the impacts on forests and timber markets is difficult given the long time lags between the planting and harvesting of trees.

Despite the many practical problems with understanding climate change impacts on forested ecosystems and timber markets, the combination of historical observation, modeling results, and experimental data allows us to draw several conclusions. Future research will certainly revise these conclusions, but the following points summarize the most important findings in the research to date regarding the overall impacts of climate change on forest ecosystems and timber markets over the next century:

1. Tree species generally are expected to migrate northward or to higher altitudes in response to increased temperatures. While species will adapt over time by moving from one region to another, differential rates of change may cause significant differences in the types of natural stands in the future. Rates will depend critically on (a) how fast seeds migrate into new regions that are climatically suitable for a species after a climate change, (b) changes in the spread of insects and disease, (c) the spread of wildfire in different climates, and (d) human interventions to promote species migration.

2. Forest productivity is expected to change, but the changes could be positive or negative. Forests could become more or less productive, depending on how much climate changes (including both temperature and precipitation), how forests respond to higher carbon concentrations in the atmosphere, whether mortality changes, and whether disturbance-induced dieback increases or decreases. Many of these factors are expected to vary from region to region, suggesting that economic impacts are likely to differ among regions in the United States.

3. The effect of additional carbon dioxide in the atmosphere on forested ecosystems (“carbon fertilization”) is complex and uncertain, but it has large implications for understanding how forest productivity will change. Most studies suggest that forest area and productivity will increase if carbon fertilization enhances forest growth, but will decline if carbon fertilization does not occur. Plant level experiments suggest that carbon fertilization will enhance tree growth, at least for some period of time. Scaling these results up to the ecosystem level is complex, but available studies suggest that carbon fertilization will be limited by competition, disturbance, and nutrient limitations. It is important to continue developing a better understanding of carbon fertilization effects, particularly at the ecosystem scale.

4. Changes in the frequency and severity of forest disturbance, such as storm damage, fires, and pests are likely to affect forest structure and function. The impact on markets, while generally negative, can be ameliorated by salvage. At the market level, salvage associated with disturbances can increase timber supply and reduce prices in the short term, which benefits consumers. However, increased disturbance and lower prices generally have negative effects on landowners.

5. United States timber markets have low susceptibility to climate change because of the large stock of existing forests, technological change in the timber industry, and the ability to adapt. The United States currently consumes less timber than grows within the country each year, providing a cushion if climate change has short-term impacts on supply. Further, companies already substitute a wide array of species in end products, so that if particular species are negatively affected by climate change, markets can adapt by changing the types of species used in the production of end products. In addition, landowners can assist natural migration of timber by planting southern species in the North.

6. Economic studies have tended to find small negative to positive overall effects on timber production in the United States. While the studies have looked at a wide range of potential climate change effects across species within the United States, the net productivity effects used by the studies have tended to be positive over the long-term. Higher forest productivity translates into increased timber yield, increased timber inventory, increased supply, and lower prices. Lower prices generate overall net benefits, although they primarily benefit consumers at the expense of landowners. Lower forest productivity has the opposite effect.

7. Northern states may gain from climate change if productivity increases and if southern species move North, while southern states may lose production. Producers in southern regions are the most vulnerable to climate change because they have a large share of the nation’s current timber production capital, and the highly productive species in that region are sensitive to potential drying effects. Northern states are generally predicted to gain productivity and market share during climate change.

8. Understanding the economic effects of climate change on timber production is limited by scientific understanding of several key factors that control the response of natural and managed forests to climate change. Additional research is needed to enable ecologists and foresters to develop a more robust understanding of future changes in U.S. climate, ecosystem responses to climate change, the relationship between forest productivity and timber yield, and adaptation options available to foresters. Future clarification of these uncertainties will permit more informed assessments of the economic impacts of climate change to the forestry sector.

About the Authors

Dr. Herman H. Shugart
University of Virginia

Herman H. Shugart is the W.W. Corcoran Professor of Environmental Sciences at the University of Virginia. Prior to joining the University of Virginia in his current capacity in 1984, he worked for 13 years in Tennessee – eventually as a Senior Research Scientist at Oak Ridge National Laboratory and as a Professor in Botany at the Graduate Program in Ecology at the University of Tennessee. Dr. Shugart has also served as a Visiting Fellow in the Australian National University (1978-1979, 1993-1994), in Australia’s Commonwealth Industrial and Scientific Research Organization, Division of Land Use Research (1982) and Division of Wildlife and Ecology (1993-1994), in the International Meteorological Institute at the University of Stockholm, Sweden (1984), and in the International Institute of Applied Systems Analysis, Laxenburg, Austria (1987,1989).

Dr. Shugart has served on the editorial board of several scholarly journals including Ecology, Ecological Monographs, Annual Reviews in Ecology and Systematics, Biological Conservation, Landscape Ecology, Journal of Vegetation Science, Forest Science, Global Change Biology, and The Australian Journal of Botany. He is the author of 300 publications including 12 books, 65 book chapters and 114 papers in peer-reviewed journals. A recent book, Terrestrial Ecosystems in Changing Environments was published in 1998 by Cambridge University Press, which reviews the ecological issues of predicting responses to global and regional climatic change. Recent honors include his election, as a foreign member, to the Russian Academy of Sciences in recognition of his work in Forest Ecology (2001); his designation as the 1999 Distinguished Alumnus from his alma mater, Department of Biological Sciences, University of Arkansas; and his identification as a Highly Cited author (top 1/2 percentile of scientific citations) in the area of Ecology/Environment by the Institute for Scientific Information.

Dr. Shugart received B.S. and M.S. degrees in Zoology at the University of Arkansas and received his Ph.D. (also in Zoology) from the University of Georgia in 1971.

Roger A. Sedjo
Resources for the Future

Dr. Sedjo is a Senior Fellow and the Director of the Forest Economics and Policy Program at Resources for the Future (RFF), a Washington based policy research organization, and the President of the Environmental Literacy Council (ELC), a nonprofit environmental education group. Dr. Sedjo has written extensively on forest and environmental issues, both domestic and international, having authored or edited fourteen books related to forestry, natural resources and the environment. His early work focused on timber supply and forest plantation issues, while more recent work is devoted more to the environmental aspects of forests.

Dr. Sedjo has served on a number of scientific panels and was a member of the Secretary of Agriculture’s Committee of Scientists, which made recommendations on Forest Service planning, and edited a recent book, A Vision for the US Forest Service (2000). He was a co-Chair of the chapter on “biological carbon sinks” in the Intergovernmental Panel on Climate Change’s (IPCC) Third Assessment Report (2001). He was also a contributor to two chapters in the IPCC’s Second Assessment Report (1995 ). Additionally, he has worked for the past several years with the Japanese Government in assessing their options toward meeting their carbon targets under the Kyoto Protocol. Recently, he has completed a study for the Department of Energy that resulted in the report, Estimating Carbon Supply Curves for Global Forests and Other Land Uses (with Brent Sohngen and Robert Mendelsohn). In addition, his recent papers on climate change have been featured in Bulletin of the Forestry and Forest Products Research Institute, Journal of Agricultural and Resources Economics, and Environment Science and Policy.

Dr. Sedjo has been a consultant to a wide array of organizations including the World Bank, the Global Environmental Facility, the Asian Development Bank, U.S. Agency for International Development, the OECD, Harvard Institute for International Development and others. Dr. Sedjo earned his B.A. and M.S. degrees at the University of Illinois, and a Ph.D. at the University of Washington (Seattle).

Dr. Brent L. Sohngen
The Ohio State University

Brent Sohngen is an associate professor in the Department of Agricultural, Environmental, and Development Economics at The Ohio State University. Prior to his appointment at Ohio State in 1996, he was a Gilbert White Postdoctoral Fellow at Resources For the Future in Washington, D.C.

His primary research interests lie in modeling land-use and land-cover change, examining impacts of climate change in the forestry sector, and the economics of nonpoint source pollution. Dr. Sohngen also leads an extension and outreach program in environmental and natural resource economics. The program focuses on linking research on natural resource and environmental economics to natural resource policy and management issues in the state of Ohio.

He obtained a bachelor’s degree from the Department of Agricultural Economics at Cornell University in 1991, and a doctorate from Yale University in 1996.

Brent Sohngen
Herman Shugart
Roger Sedjo
0

Solutions FAQs

Back to Main FAQs Page

What can the average individual do to help combat climate change? Can it be an individual effort, or is this really the responsibility of corporations and governments to resolve?

  • Participation by individuals is key to ultimately curbing global climate change.
  • The following are examples of effective, yet simple activities: reducing energy use at home by purchasing energy efficient home appliances; planting trees to absorb carbon from the atmosphere; walking or taking public transportation instead of driving; making smart consumer choices by purchasing environmentally sound products and energy-efficient vehicles; and practicing waste minimization, product reuse, and recycling.

How are we going to reduce carbon dioxide emissions with an increased consumer demand for power?

  • First, not all GHG emissions are CO2 emissions, and not all CO2 emissions are from power use. So you can reduce GHG emissions in other sectors like agriculture, forestry, and waste management without even addressing power. In addition, expanding the production of renewable energy and improving energy efficiency are ways to meet consumer demands for power without increasing CO2 emissions.

What are states doing to address climate change?

  • States have shown a great deal of interest in mitigating climate change. They have found that activities that reduce GHG emissions also have other benefits such as curbing pollution, reducing traffic, and generally improving the local quality of life.
  • States have conducted GHG inventories and initiated state action plans that identify and implement policies to reduce GHG emissions.
  • Other state initiative include providing loans and tax incentives to encourage energy efficiency, investing in carbon sequestration research and public transportation, establishing registries for businesses to report their GHG emissions reductions, and providing venues for trading emissions credits.
  • For more information on state action, visit our database of state case studies or read our report.

Over the past several years, how much has the development of clean coal technology reduced greenhouse gas emissions in the US? Do you see a real potential for its use?

  • Clean coal technology is a generic term for a set of technologies that reduce harmful emissions from coal burning. Some of these technologies reduce greenhouse gas emissions, but some only address other air pollutants, such as sulfur dioxide. Thus far clean coal technology has made a greater impact on these other pollutants, but there are promising technologies that would reduce GHG emissions from coal burning, or would capture and sequester CO2 emissions from coal burning. To the extent we continue to use coal, it is important to take advantage of these technologies.

What role, if any, can renewable energy play in CO2 reduction?

  • Renewable energy plays a small role now, but it is expected to play an increasingly important role over time. Wind and biomass energy are already cost-competitive with other forms of electric generation in some instances. Great technological strides have been made recently in hydrogen-powered fuel cells. There is enormous potential for solar energy and hydrogen to power our homes and cars in the future.
  • Several states have adopted renewable portfolio standards that require an increasing role for renewables as sources of electric power.

Because transportation accounts for a significant of greenhouse gas emissions internationally, how do you propose we reduce emissions in this sector? What do you think the technologies of the future may be?

  • Some technologies that will reduce emissions are already here, such as hybrid-electric vehicles like the Toyota Prius.
  • There have been exciting breakthroughs in hydrogen-powered fuel cells. Both fuel cells and biofuels are potential options for the future.
  • In the United States, it is likely that alternative and replacement fuels along with vehicle efficiency improvements will be the focus of a transportation emission mitigation strategy, rather than reducing driving. However, policies such as better traffic management, better urban design, and promotion of telecommuting might achieve multiple benefits, including GHG emission reductions.

    Report: Reducing Greenhouse Gas Emissions from U.S. Transportation
    In Brief: Taking Climate Change into Account in U.S. Transportation

Can we really live without fossil fuels, and what are the alternatives?

  • Yes, we can move away from fossil fuels, but not overnight. Our economy is currently dependent on fossil fuels, but it is not necessary that it remain dependent on them. Over time, with innovation, market incentives, and the right policies, we can transition to different fuels, different infrastructure, higher efficiency, and different technologies.
  • We need to concentrate on the development of alternative energy sources such as wind energy and solar power. Technological innovation in energy efficiency is also important.

How will workers be affected as climate change policies are implemented? And how can the adverse impacts be reduced?

  • While it is important to recognize that the costs of addressing climate change are likely to fall disproportionately on certain industries, communities, and workers, the design and implementation of effective government programs can greatly assist workers adversely affected by climate change policies.
  • Programs may include substantial retraining and education for laid-off workers, advance notice of layoffs when possible, substantial income support for program participants, and maintenance of laid-off workers' health and pension benefits until they find suitable employment.

    Report: Community Adjustment to Climate Change Policy
    Report: Worker Transition: Global Climate Change

Press Release: New Report: Climate Change Poses Challenges for U.S. Forestry

For Immediate Release: 
February 26, 2003

Contact:  Katie Mandes
(703) 516-0606

NEW REPORT: Climate Change Poses Challenges for U.S. Forestry


Washington, DC - One-third of U.S. lands are covered by forests, making forest ecosystems one of the nation's most prominent natural resources. In addition to their contribution to biodiversity, water quality, and recreation, forests also play a significant role in the U.S. economy, and forestry or forestry-related enterprises are the dominant industries in many U.S. communities. According to a new study by the Pew Center on Global Climate Change, the U.S. forestry sector will face a number of challenges in the next century due to the impacts of climate change.

The Pew Center report, Forests and Global Climate Change: Potential Impacts on U.S. Forest Resources, explores the challenges climate change will pose to forest ecosystems and related economic enterprises over the next century.

"Changes in forest productivity, the migration of tree species, and potential increases in wildfires and disease could cause substantial changes to U.S. forests," said Eileen Claussen, President of the Pew Center on Global Climate Change. "Moreover, these ecological impacts will have direct implications for our economy. The timber industry in the southern United States is particularly vulnerable."

The key conclusions of the report include:


Forest location, composition, and productivity will be altered by changes in temperature and precipitation. Climate change is virtually certain to drive the migration of tree species, resulting in changes in the geographic distribution of forest types and new combinations of species within forests. In addition, climate change is likely to alter forest productivity depending upon location, tree species, water availability, and the effects of carbon dioxide (CO2) fertilization.


Changes in forest disturbance regimes, such as fire or disease, could further affect the future of U.S. forests and the market for forest products. Increased temperatures could increase fire risk in areas that experience increased aridity, and climate change could promote the proliferation of diseases and pests that attack tree species.


U.S. economic impacts will vary regionally. Overall, economic studies indicate that the net impacts of climate change on the forestry sector will be small, ranging from slightly negative to positive impacts; however, gains and losses will not be distributed evenly throughout the United States. The Southeast, which is currently a dominant region for forestry, is likely to experience net losses, as tree species migrate northward and tree productivity declines. Meanwhile, the North is likely to benefit from tree migration and longer growing seasons.


As a managed resource, the implications of climate change for the forestry sector are largely dependent upon the actions taken to adapt to climate change. The United States currently has vast forest resources, and more timber grows within the United States than is consumed each year. If professional foresters take proactive measures, the sector may minimize the negative economic consequences of climate change.


A number of challenges currently limit our understanding of the effects of climate change on forestry. Existing projections for future changes in temperature and precipitation span a broad range making it difficult to predict the future climate that forests will experience, particularly at the regional level. Thus, current projections could fail to accurately predict the actual long-term impacts of climate change for the forestry sector.

Part of "Impacts" Series

Forests and Global Climate Change: Potential Impacts on U.S. Forest Resources, was prepared for the Pew Center by Herman Shugart (University of Virginia), Roger Sedjo (Resources for the Future), and Brent Sohngen (The Ohio State University). It is the ninth in a series of Pew Center reports examining the potential impacts of climate change on the U.S. environment. Other Pew Center reports focus on domestic and international policy issues, climate change solutions, and the economics of climate change.

Click here for a complete copy of this report and previous Pew Center reports.

Climate Change: The Next 50 Years - One Decade at a Time

Climate Change:  The Next 50 Years - One Decade at a Time

Remarks of Eileen Claussen, President
Pew Center on Global Climate Change

SRI in the Rockies

October 18, 2002

Thank you very much and good morning. It is a pleasure to be here. I have to say that even the sound of SRI in the Rockies has an appealing ring to it. You can probably make just about anything sound better by adding those three little words: "In the Rockies." They're certainly more attractive than the three words I usually hear: "Inside the Beltway."

So I'd like to start by saying thank you to the conference organizers - not only for this wonderful setting, but also for the opportunity to speak with you about what I believe to be one of the most profound challenges of our time: the challenge of global climate change.

But I'd also like to say thank you to all of you. Because after many years of working to protect our environment, I've come to two very important realizations. First, you're better off working with the marketplace than against it. And second, positive change more often than not is the product of committed individuals who take the time to figure out what's right, and then act on it. Socially responsible investing blends those two realities into a very powerful force for change. And I can't tell you how pleased I am to be speaking to the SRI community about meeting the challenge of global warming. So again, thank you.

I'd like to cover a lot of ground today. I'll start with a quick overview of what science tells us about the risks and realities of global warming. Then I'll lay out in broad terms the challenge we face in the decades ahead if we are to avert the worst consequences of climate change. I'll highlight some of the efforts already underway to meet that challenge, both in government and in the business community. And finally, I'd like to talk about the critical role that all of you can and must play in getting more people and more companies to do the right and responsible thing.

So, as any informed discussion of climate change should, let's start with the science. In a word, it's compelling. There is overwhelming scientific consensus on three basic points: the earth is warming; this warming trend is likely to worsen; and human activity is largely to blame. Yes, you can find scientists who will argue otherwise. But these are the findings of the Intergovernmental Panel on Climate Change, which draws on the expertise of hundreds of climate scientists around the world. They are also the findings of a special, well-balanced panel put together by the National Academy of Sciences at the request of President Bush.

True, the earth's temperature has always fluctuated. But ordinarily these shifts occur over the course of centuries or millennia, not decades. The 1990s were the hottest decade of the entire millennium. The last five years were among the seven hottest on record. Scientists project that over the next century, the average global temperature will rise two to ten degrees Fahrenheit. A ten-degree increase would be the largest swing in global temperature since the end of the last ice age 12,000 years ago.

What are the likely consequences? We can expect rising sea levels, increased flooding and increased drought& more powerful storms, extended heat waves, and other types of extreme weather events. In some communities, global warming is no longer a theoretical matter. The impacts are being felt right now. Just ask the people of Alaska, where roads are crumbling and homes are sagging as the permafrost begins to melt.

Increasingly, we will all feel the impacts in our pocketbooks and our portfolios. Earlier this month, the United Nations Environment Program released a report done in collaboration with some of the world's largest banks, insurers and investment companies. The report found that losses resulting from natural disasters appear to be doubling every 10 years and, if this trend continues, will amount to nearly $150 billion over the coming decade. This summer's wildfires here in the West and floods in central Europe are some of the latest examples. It's impossible to conclusively link any one of these disasters to the broader warming trend. But linked or not, these events give us a very real and very frightening preview of what's in store if the warming trend continues.

So what do we do about it? How do we protect ourselves, and future generations, from the rising risks of global warming? The short answer is that we must fundamentally transform the way we power our global economy. To keep our planet from overheating, we must dramatically reduce emissions of carbon dioxide and other greenhouse gases. The primary source of these gases is the combustion of fossil fuels. So our goal over time must be to steadily reduce our reliance on coal and oil and to develop new sources of energy - clean energy.

Clearly, this is a tall order. In fact, it will take nothing short of a new industrial revolution. Some revolutions happen overnight. This one will take time. It takes time to develop and adopt new technologies. It takes time to turn over our capital stock. But we can't afford to let this revolution take too long - every day, our emissions of greenhouse gases grow larger. So the first step in this revolution might be setting a goal - a long-term goal. Allow me to propose one. I propose that within 50 years we have in place all the technologies we need to power our economy without endangering our climate. I think it's a reasonable goal, one we can reach - provided we start right now and keep at it, one decade at a time.

This 50-year climate revolution must reach across each of the major energy-producing and -consuming sectors of our economy. In the electricity sector, we must burn coal more efficiently, increase our use of natural gas -- and ultimately move to renewables like solar and wind. In transportation, we can dramatically improve fuel economy right now, but at the same time should be switching to hybrid engines and developing alternatives like hydrogen fuel cell vehicles that will make the internal combustion engine obsolete. In the building sector, we need to take advantage of all the smart designs available right now to make our homes, offices and stores far more energy efficient. And in the industrial sector, we need to redesign the entire chain of commerce -- from inputs, to production processes, to product mixes, to the reuse and recycling of both waste and the products themselves.

All told, these changes imply technological and economic transformation on an unprecedented scale. How do we start? Here are some of the things we can do in decade one to get this revolution underway.

We can start by requiring companies to track and disclose their greenhouse gas emissions. We can assure companies taking steps now to reduce their emissions that their efforts will be recognized in any future regulatory system. We can raise efficiency standards. We can make strategic public investments in promising technologies. We can encourage farmers and foresters to adopt practices that take carbon from the atmosphere and store it in soil, crops and trees. We can step up efforts to determine whether we can safely and permanently sequester carbon in geologic formations deep underground. And we can begin building an economy-wide system that sets mandatory targets for reducing emissions and uses market approaches like emissions trading to meet them at the lowest possible cost.

So that's the challenge - revolutionize the way we power our economy in 50 years, one decade at a time. Is there any evidence that we're stepping up to the challenge? Not enough, I'm afraid, but perhaps more than you think.

Let's look first at the international picture. After a decade of negotiations, we are on the verge of establishing the first international constraints on greenhouse gas emissions. The European Union and Japan have ratified the Kyoto Protocol and if, as promised, Russia follows suit, the treaty will enter into force next year. Kyoto is only a start - its targets are far short of the emission reductions that ultimately will be needed, and it doesn't address developing countries, where much of the emissions growth in the coming decades will occur. But Kyoto is an important start. It lays a foundation and it reflects the determination of the international community to face up to this challenge.

The United States, of course, has chosen to stand outside this international effort. President Bush has rejected Kyoto and offered up instead a domestic strategy that relies exclusively on voluntary action. The President's strategy sets a goal of reducing greenhouse gas intensity 18 percent by 2012. That might sound good, but it allows actual emissions to keep on growing. It is essentially business as usual. It effectively writes off decade one.

But if you look past the administration - if you look at what's happening elsewhere in Washington and across the country - the picture is a bit more encouraging. And that's in part because a funny thing happened on the way to Kyoto. Just as the President's rejection helped save the Protocol by rallying other nations to its defense, it elevated the issue here at home as well - both in the press, and in the political arena.

In Congress, members of both parties are more eager than ever to demonstrate their interest in climate protection. Nearly twice as many climate change bills were introduced in Congress over the past year as in the previous four years combined. One of the major sticking points in the stalled negotiations over an energy bill is a set of bipartisan climate provisions that would force the administration to start taking the issue seriously.

And in an interesting bipartisan pairing, Senators Joe Lieberman and John McCain plan to introduce a bill this year setting a national cap on greenhouse gas emissions and allowing companies to buy and sell carbon credits. The bill is not likely to move anywhere fast, but it will help spark a long overdue debate on just how the United States will live up to its obligations as the world's largest emitter of greenhouse gases.

One thing that's interesting is that when you get outside Washington - when you're no longer inside the Beltway, that is - you find people moving right past debate to action. A growing number of states and communities are taking steps to cut their greenhouse gas emissions. At least 42 states have programs that, while not necessarily directed at climate change, are achieving real emission reductions. Texas and 13 other states require utilities to generate a share of their power from renewable sources. New York State's new energy plan sets a goal of reducing emissions 10 percent below 1990 levels by 2020. Some states are going beyond target-setting and establishing direct controls on carbon from power plants and - in the case of California - from cars and SUVs.

The message being sent by the states is that with or without Kyoto - and for that matter, with or without Washington - there is growing support in the United States for getting serious about climate change.

Increasingly, we are hearing the same message from the business community as well. Many companies are not waiting for government mandates - they're taking steps to reduce their emissions right now. At last count, we had identified more than 40 major companies that have publicly committed themselves to greenhouse gas reduction targets.

Let me share just a few examples. Alcoa is aiming to reduce its emissions 25 percent below 1990 levels by 2010. DuPont is aiming for a 65 percent reduction. Toyota, IBM, Intel, Johnson & Johnson& all have adopted targets for reducing emissions. Rohm and Haas, TransAlta, and BP have already achieved their targets and set new ones. BP, in fact, has cut emissions 10 percent below 1990 levels - eight years ahead of target - and now has pledged to keep them there at least until 2010.

The list of companies taking voluntary action keeps growing. Many are signing up with EPA's Climate Leaders program, which helps companies measure their emissions and begin to reduce them. Even Exxon-Mobil, a leading champion of the administration's business-as-usual strategy, recently ran ads touting its efforts to get a handle on its emissions.

These voluntary efforts are encouraging. They're to be commended. But they're not enough. The companies that are truly committed to tackling climate change know that we will never achieve the deep emission cuts we need unless everyone moves far enough, and fast enough, in the right direction. And that will happen only if the government requires it. That is why the companies we work with at the Pew Center recently called for the development of a comprehensive national climate strategy that is flexible and market-based but also has teeth - a strategy of mandatory, not voluntary, reductions.

And this leads me, finally, to your role in launching our 50-year climate revolution. I said earlier that I've learned it's better to work with the market than against it. In fact, I believe that ultimately only the market can mobilize the resources and the ingenuity needed to meet the challenge of climate change. The market, of course, will only deliver if there is a demand. That is why mandatory government policies are so critical. But the demand should not come from government alone. It should come from each of us as well - as consumers and as investors. And there, you are at the leading edge.

As socially responsible investors, you can help distinguish between the companies that are just painting themselves green, the companies that are actually cutting their emissions, and the companies that are going the next step and calling on government to mandate action by all. To do that, you need to need to know how a company is managing its carbon risk - what its emissions look like and what it's doing to reduce them. You need to know which companies are seizing the opportunities presented by climate change - which companies are looking ahead and investing now in the technologies we need in place 50 years from now. And you need to know which companies are pressing our elected leaders to do the right thing.

Increasingly, investors are demanding the information they need to make these assessments, and they're demanding corporate accountability on climate change. This year saw a record number of shareholder resolutions on climate change, and record support for them. Some drew votes of nearly 30 percent. In most cases, the resolutions were withdrawn when the companies agreed to enter into dialogue about their greenhouse gas emissions and their disclosure practices.

We talk a lot about the environment. But if you are a business, or an investor, or a fund manager, the environment within which you operate is the market. And the rules of the market will change. The climate, in essence, will stop being free. There will be a cost for emitting carbon. Those who understand that reality, and make the adjustment, will not only survive but thrive. Because in every change there is opportunity, and the rewards flow to those who seize them first. But those who ignore the realities and fail to adjust will pay the price.

You can help focus attention on these new realities - on both the risks and the opportunities. Keep impressing upon other investors, analysts, and companies themselves that climate change is a serious challenge that demands serious action. Tell them that if they want to be winners in the carbon-constrained world of the future, the time to start is now. Make sure CEOs understand that they ignore this issue at the peril of their companies and their shareholders -- not to mention, future generations.

Keep spreading the word because the market is both a harsh arbiter and the great mobilizer. And you are the market. 

Download Transcript (in Word format)

Coastal and Marine Ecosystems & Global Climate Change: Potential Effects on U.S. Resources

Download Report

Coastal and Marine Ecosystems & Global Climate Change: Potential Effects on U.S. Resources

Prepared for the Pew Center on Global Climate Change
August 2002

By:
Victor S. Kennedy, University of Maryland
Robert R. Twilley, University of Louisiana at Lafayette
Joan A. Kleypas, National Center for Atmospheric Research
James H. Cowan, Jr., Louisiana State University
Steven R. Hare, International Pacific Halibut Commission

Press Release

Download Entire Report (pdf)

Foreword

Eileen Claussen, President, Pew Center on Global Climate Change

The world’s oceans cover approximately 70 percent of the Earth’s surface, indicating their importance to the global environment. In addition to having a large influence on global heat transport and precipitation, the oceans are comprised of diverse habitats that support a wealth of marine wildlife. They also provide humans with a wide variety of goods and services including foods, recreational opportunities, and transportation corridors. Based upon current scientific evidence, emissions of greenhouse gases from human activities are projected to cause significant global climate change during the 21st century. Such climate change will create novel challenges for coastal and marine ecosystems that are already stressed from human development, land-use change, environmental pollution, and over-fishing.

“Coastal and Marine Ecosystems & Global Climate Change” is the eighth in a series of Pew Center reports examining the potential impacts of climate change on the U.S. environment. It details the likely impacts of climate change over the next century on U.S. coastal and marine ecosystems, including estuaries, coral reefs, and the open ocean. Report authors, Drs. Victor Kennedy, Robert Twilley, Joan Klepas, James Cowan, Jr., and Steven Hare find:

Temperature changes in coastal and marine ecosystems will influence organism metabolism and alter ecological processes such as productivity and species interactions. Species are adapted to specific ranges of environmental temperature. As temperatures change, species’ geographic distributions will expand or contract, creating new combinations of species that will interact in unpredictable ways. Species that are unable to migrate or compete with other species for resources may face local or global extinction.

Changes in precipitation and sea-level rise will have important consequences for the water balance of coastal ecosystems. Increases or decreases in precipitation and runoff may respectively increase the risk of coastal flooding or drought. Meanwhile, sea-level rise will gradually inundate coastal lands. Coastal wetlands may migrate inland with rising sea levels, but only if they are not obstructed by human development.

Climate change is likely to alter patterns of wind and water circulation in the ocean environment. Such changes may influence the vertical movement of ocean waters (i.e., upwelling and downwelling), increasing or decreasing the availability of essential nutrients and oxygen to marine organisms. Changes in ocean circulation patterns can also cause substantial changes in regional ocean and land temperatures and the geographic distributions of marine species.

Critical coastal ecosystems such as wetlands, estuaries, and coral reefs are particularly vulnerable to climate change. Such ecosystems are among the most biologically productive environments in the world. Their existence at the interface between the terrestrial and marine environment exposes them to a wide variety of human and natural stressors. The added burden of climate change may further degrade these valuable ecosystems, threatening their ecological sustainability and the flow of goods and services they provide to human populations.

The authors and the Pew Center gratefully acknowledge the input of Drs. Richard Beamish, Michael Fogarty, and Nancy Rabalais on this report. The authors would also like to thank Andrea Belgrano, Jay Blundon, Lou Codispoti, Victoria Coles, Raleigh Hood, Richard Kraus, Thomas Malone, Ray Najjar, Roger Newell, Michael Pace, Frieda Taub, and Peter Vogt for comments on early drafts. The Pew Center would also like to thank Joel Smith of Stratus Consulting for his assistance in the management of this Environmental Impacts Series.

Executive Summary

Since life began on earth, changes in the global climate have affected the distribution of organisms as well as their interactions. However, human-induced increases in atmospheric concentrations of greenhouse gases are expected to cause much more rapid changes in the earth’s climate than have been experienced for millennia. If this happens, such high rates of change will probably result in local if not total extinction of some species, the alteration of species distributions in ways that may lead to major changes in their interactions with other species, and modifications in the flow of energy and cycling of materials within ecosystems.

The predicted changes may have a significant effect on coastal ecosystems, especially estuaries and coral reefs, which are relatively shallow and currently under stress because of human population growth and coastal developments. Significant environmental factors that affect the structure (e.g., plant and animal composition) and function (e.g., plant and animal production, nutrient cycling) of estuarine and marine systems and that are expected to be part of global climate change include temperature, sea-level rise, the availability of water and associated nutrients from precipitation and runoff from land, wind patterns, and storminess. Temperature, in particular, influences organism biology, affects dissolved oxygen concentrations in water, and plays a direct role in sea-level rise and in major patterns of coastal and oceanic circulation.

Predictions of the effects of climate change on coastal and marine ecosystems are associated with varying degrees of confidence. There is some confidence in predictions of how increases in temperature will affect plant and animal physiology, abundances, and distributions; aquatic oxygen concentrations; and sea level. There is also some confidence in predictions of the effects of sea-level rise on shallow continental margins, including flooding of wetlands, shoreline erosion, and enhanced storm surges. There is less confidence regarding temperature’s influence on interactions among organisms, and even less as to its effects on water circulation patterns. It is also difficult to predict the effects of climate change on precipitation, wind patterns, and the frequency and intensity of storms.

Many species are sensitive to temperatures just a few degrees higher than those they usually experience in nature. A rise in temperature as small as 1oC could have important and rapid effects on mortality of some organisms and on their geographic distributions. Given that temperature increases in the coming century are predicted to exceed 1oC, the major biological change resulting from higher temperatures in U.S. coastal waters may be altered distributions of coastal organisms along the east and west coasts. The geographic ranges of heat-tolerant species such as commercial shrimp on the East Coast may expand northward, while the southern range boundaries of heat-intolerant organisms such as soft clams and winter flounder may retreat northward. The more mobile species should be able to adjust their ranges over time, but less mobile species may not. Such distributional changes would result in varying and novel mixes of organisms in a region, leaving species to adjust to new predators, prey, parasites, diseases, and competitors. Some species would flourish and others would not, and we have no way of predicting at present which species would prevail. Fisheries would also be affected as some species are lost from a region or as others arrive. Warmer conditions would support faster growth or a longer growing season for aquacultured species, but might become too warm for some species in a particular region, requiring a change in the species being cultured.

Because water expands and glaciers melt as temperatures warm, higher temperatures would raise sea levels, inundating coastal lands and eroding susceptible shores. In salt marsh and mangrove habitats, rapid sea-level rise would submerge land, waterlog soils, and cause plant death from salt stress. If sediment inputs were limited or prevented by the presence of flood-control, navigational, or other anthropogenic structures, marshes and mangroves might be starved for sediment, submerged, and lost. These plant systems can move inland on undeveloped coasts as sea levels rise on sedimentary shores with relatively gentle slopes, but seaside development by humans would prevent inland migration. Marshes and mangroves are critical contributors to the biological productivity of coastal systems and function as nurseries and as refuges from predators for many species. Thus their depletion or loss would affect nutrient flux, energy flow, essential habitat for a multitude of species, and biodiversity. Some organisms might thrive (e.g., shrimp, menhaden, dabbling ducks, some shorebirds), at least over the short term as marshes break up and release nutrients or become soft-bottom habitat. Other organisms would be lost from affected areas if their feeding or nesting grounds disappeared and they could not use alternative habitats (e.g., Black and Clapper Rails, some terns and plovers).

Climate change may decrease or increase precipitation, thereby altering coastal and estuarine ecosystems. Decreased precipitation and delivery of fresh water alters food webs in estuaries and affects the amount of time required to flush nutrients and contaminants from the system. Although reduced river flow would decrease nutrient input in estuaries with relatively uncontaminated watersheds, there could be different effects in polluted watersheds that contain point sources of nutrients and contaminants that are not a function of river flow. The combined effects of human development and reduced river flow would degrade water quality conditions, negatively affecting fisheries and human health through such changes as increased presence of harmful algal blooms and accumulation of contaminants in animals and plants. Increased rainfall and resultant freshwater runoff into an estuary would increase stratification of the water column, leading to depleted oxygen concentrations in estuaries with excess nutrients. It would also change the pattern of freshwater runoff in coastal plain watersheds, such as along the southern Atlantic coast and in the Gulf of Mexico. In those regions where water resources are managed by humans, the effects of increased flooding would depend on how managers controlled regional hydrology.

Wind speed and direction influence production of fish and invertebrate species, such as in regions of upwelling along the U.S. West Coast. If upwelling is slowed by changes in wind and temperature, phytoplankton production could be lowered. Where upwelling increases as a result of climate change, productivity should also increase. In some coastal regions, alongshore wind stress and buoyancy-driven density differences help produce water movements that transport larval fish and invertebrates to nurseries, such as in estuaries. Climate-related changes in these circulation patterns that hinder such transport might alter the species composition of coastal ecosystems.

Increases in the severity of coastal storms and storm surges would have serious implications for the well-being of fishery and aquaculture industries, as has been demonstrated by the effects of recent intense hurricanes along the U.S. East Coast. Most ecosystems can recover rapidly from hurricanes, but the anthropogenic alteration of coastal habitats may increase the ecological damage associated with more severe storms.

The immense area and the modest extent of our knowledge of the open ocean hamper predictions of how ocean systems will respond to climate change. Nevertheless, it is clear that increased temperature or freshwater input to the upper layers of the ocean results in increased density stratification, which affects ocean productivity. Coupled physical/biogeochemical models predict a net decrease (~5 percent) in global productivity if atmospheric concentrations of carbon dioxide (CO2) reach a doubling of pre-industrial levels, increasing oceanic thermal stratification and reducing nutrient upwelling. Because productivity varies regionally, simple extrapolation to particular U.S. marine waters is difficult, although some high-latitude areas might benefit from warmer temperatures that lengthen the growing season. Open ocean productivity is also affected by natural interannual climate variability associated with large-scale climate phenomena such as the El Niño-Southern Oscillation. Climate-driven changes in the intensity or timing of any of these phenomena could lead to marked changes in water column mixing and stratification and, ultimately, a reorganization of the ecosystems involved, for better or worse.

Increased CO2 concentrations lower ocean pH, which in turn changes ocean carbonate chemistry. This may have negative effects on the myriad planktonic organisms that use calcium carbonate to build their skeletons. Some of these organisms appear to play important roles in ocean-atmosphere interactions, but we cannot yet predict any effects that might arise from their diminishment.

Finally, coral reefs, which are already threatened by multiple stressors such as abusive fishing practices, pollution, increased disease outbreaks, and invasive species, would also be at risk from changes in seawater chemistry, temperature increase, and sea-level rise. Lower ocean pH and changed carbonate chemistry would decrease the calcification necessary for building coral reef material. Increased warming would lead to coral bleaching, the breakdown in the symbiotic relationship between the coral animal and the unicellular algae (zooxanthellae) that live within coral tissues and allow corals to thrive in nutrient-poor waters and to secrete massive calcium carbonate accumulations. If sea levels were to rise at a pace faster than corals could build their reefs upward, eventually light conditions would be too low for the zooxanthellae to continue photosynthesis. On reefs near low-lying coastal areas, sea-level rise would likely increase coastal erosion rates, thus degrading water quality and reducing light penetration necessary for photosynthesis and increasing sedimentation that smothers and stresses coral animals. Losses of coral reefs would mean losses in the high biodiversity of these systems as well as the fisheries and recreational opportunities they provide.

About the Authors

Dr. Victor S. Kennedy
University of Maryland Center for Environmental Science

Dr. Kennedy is a marine ecologist who has spent over 30 years working as a research scientist on the ecology and physiology of aquatic animals. His early training included studying the effects of temperature on survival and physiology of estuarine species. His research in the 1960s helped convince the State of Maryland to revise its regulations governing discharge of heated water from power plants and other industrial facilities into Chesapeake Bay. Beginning in 1989, he used his experience with the effects of temperature on aquatic organisms to write papers and make presentations at scientific meetings on the possible effects of climate change. He is a co-author of the recent assessment for the mid-Atlantic coastal region that appeared in Climate Research and is the lead author of the Center's report, "Coastal and Marine Systems and Global Climate Change."

Dr. Kennedy is a Professor at the Horn Point Laboratory of the University of Maryland Center for Environmental Science, where he performs research, directs the Multiscale Experimental Ecosystem Research Center, and teaches graduate students. In addition to his research activities in Chesapeake Bay, he has worked as a marine ecologist in the coastal waters of New Zealand and in the coastal and offshore waters of Newfoundland, Canada. He has had extensive experience as a science editor, spending five years as the Editor of the Transactions of the American Fisheries Society, as well as editing or co-editing six technical books. He served as president of two scientific organizations.

Dr. Robert R. Twilley
University of Louisiana at Lafayette

Dr. Twilley is the Director for Ecology and Environmental Technology at the University of Louisiana at Lafayette. Dr. Twilley received his B.S. and M.S. (Biology) from East Carolina University, and his Ph.D. (Botany/Systems Ecology) from the University of Florida, after which he completed a postdoctoral fellowship in coastal oceanography at the University of Maryland. His research interests include ecosystem ecology, estuarine and coastal ecosystems; biogeochemistry of mangroves and tropical estuarine ecosystems; and ecosystem management and restoration of coastal regions. Among his various professional activities, Dr. Twilley currently serves on the editorial boards for Mangroves and Salt Marches and Environmental Science and Policy, and he previously served as a guest editor for Ecology and as an associate editor for Estuaries. Dr. Twilley is an active member in several professional societies including the Ecological Society of America, Estuarine Research Federation, Society of Wetland Science, and the American Association for the Advancement of Science. In addition to serving on the Board of Directors for the Society of Wetland Scientists (1993-97), Dr. Twilley has contributed to 71 publications and received a Distinguished Professor award for the 1999-00 academic year at the University of Louisiana at Lafayette.

Joan A. Kleypas
National Center for Atmospheric Research

Joan Kleypas specializes in examining how environmental factors control coral reef development at the global scale. She has a bachelor's degree in Marine Biology (Lamar Univ., Texas), and a master's in Marine Ecology (Univ. of South Carolina). She obtained a Ph.D. from James Cook University, as a Fulbright scholar to Australia, where she conducted a reef coring program to examine the causes for differences in coral reef development in the southern Great Barrier Reef. From there she moved to the National Center for Atmospheric Research (NCAR) Boulder, Colorado, to examine not only how climate affects coral reefs, but also how coral reefs affect climate. Much of this work entailed modeling reef response to sea level and temperature changes since the last ice age. She is currently involved with issues relating to the direct effects of increasing atmospheric CO2 on coral reefs; i.e., how CO2-induced changes in seawater chemistry affect the rates at which reef-building coral and algae secrete their calcium carbonate skeletons. She continues to work at NCAR as an Associate Scientist with Scott Doney, in the broad field of ocean biogeochemistry and its role in the global carbon cycle. Dr. Kleypas has also taught numerous courses in geology, oceanography, and global change as a visiting professor at Colorado College.

Dr. James H. Cowan, Jr.
Louisiana State University

James H. Cowan, Jr. is a Professor in the Department of Oceanography and Coastal Sciences and the Coastal Fisheries Institute at the Louisiana State University. He received B.Sc. (Biology) and M.Sc. (Biological Oceanography) degrees from Old Dominion University, and M.Sc. (Experimental Statistics) and Ph.D. (Marine Sciences) degrees from the Louisiana State University. Among many other professional activities, he has thrice served on National Research Council study committees and technical review panels concerning fisheries issues, has twice served on the Ocean Sciences Division, Biological Oceanography Review Panel for the National Science Foundation, and has served as a U.S. delegate both to the International Council for the Exploration of the Sea (ICES) and the Pacific Marine Sciences Organization (PICES). He currently is Chairman of the Reef Fish Stock Assessment Panel and a member of the Standing Scientific and Statistical Committee for the Gulf of Mexico Fishery Management Council. He has served as President of the Early Life History Section, and on the Outstanding Chapter Award and Distinguished Service Award committees for the American Fisheries Society. He has almost 20 years of experience conducting fisheries research in marine and estuarine ecosystems, has authored more than 75 refereed publications in the primary fisheries literature, served four years as an associate editor for Estuaries, the journal of the Estuarine Research Federation, for 6 years as an associate editor for Gulf of Mexico Science, and currently is an associate editor for Transactions of the American Fisheries Society.

Dr. Steven R. Hare
International Pacific Halibut Commission

Dr. Steven Hare is a quantitative biologist with the International Pacific Halibut Commission in Seattle, Washington. His principal duties are to assess the status of the Pacific halibut resource, determine a sustainable harvest level and conduct life history investigations. Dr. Hare obtained his B.S. in Engineering at the University of Michigan and both his M.S. and Ph.D. at the University of Washington in Fisheries Science. His main area of research is fisheries oceanography, in particular the organizing influence of climate on marine resources of the North Pacific. Dr. Hare is a co-discoverer, and was responsible for naming, the Pacific Decadal Oscillation, an important mode of Pacific climate variability. In his 20 years as a fisheries biologist, Dr. Hare has worked for the University of Washington and National Marine Fisheries Service. He has also spent considerable time working overseas with stints in Oman and Guinea-Bissau and a tour of duty in the Peace Corps in the Solomon Islands.

James H. Cowan, Jr.
Joan A. Kleypas
Robert R. Twilley
Steven R. Hare
Victor S. Kennedy
0

Press Release: New Report: Climate Change Threatens the Future of Marine Ecosystems

For Immediate Release:  
August 14, 2002

Contact: Katie Mandes
703-516-4146

New Report: Climate Change Threatens the Future of Marine Ecosystems

Washington, DC - Comprising nearly 70 percent of the Earth's surface, the world's oceans not only play a crucial role in influencing the global climate, but also harbor some of the most diverse and important ecosystems on the globe, both ecologically and economically. According to a new study by the Pew Center on Global Climate Change, U.S. coastal and marine ecosystems will become increasingly challenged in the next century by the potential impacts of climate change.

"Climate change could likely be the 'sleeper issue' that pushes our already stressed and fragile coastal and marine ecosystems over the edge," said Eileen Claussen, President of the Pew Center on Global Climate Change. "Particularly vulnerable are coastal and shallow water areas already stressed by human activity, such as estuaries and coral reefs. The situation is analogous to that faced by a human whose immune system is compromised and who may succumb to a disease that would not threaten a healthy person."

Based on current projections for climate change in the next century, The Pew Center report, Coastal and Marine Ecosystems and Global Climate Change: Potential Effects on U.S. Resources, explores the hazards climate change will pose to delicate marine life. The key conclusions of the report include:

  • Temperature changes in coastal and marine ecosystems will influence organism metabolism and alter ecological processes such as productivity and species interactions. Species are adapted to specific ranges of environmental temperature. As temperatures change, species' geographic distributions will expand or contract, creating new combinations of species that will interact in unpredictable ways. Species that are unable to migrate or compete with other species for resources may face local or global extinction.
  • Changes in precipitation and sea-level rise will have far-reaching consequences for the water balance of coastal ecosystems. Increases or decreases in precipitation and runoff will respectively increase the risk of coastal flooding or drought. Meanwhile, sea-level rise will gradually inundate coastal lands. Coastal wetlands may migrate inland with rising sea levels, but only if they are not obstructed by human development.
  • Climate change is likely to alter patterns of wind and water circulation in the ocean environment. Such changes may influence the vertical movement of ocean waters (i.e., upwelling and downwelling), increasing or decreasing the availability of essential nutrients and oxygen to marine organisms. Changes in ocean circulation patterns can also cause substantial changes in regional ocean and land temperatures and the geographic distributions of marine species.
  • Critical coastal ecosystems such as wetlands, estuaries, and coral reefs are particularly vulnerable to climate change. Such ecosystems are among the most biologically productive environments in the world. Their existence at the interface between the terrestrial and marine environment exposes them to a wide variety of human and natural stressors. The added burden of climate change may further degrade these valuable ecosystems, threatening their ecological sustainability and the flow of goods and services they provide to human populations.

" It is increasingly apparent that the United States needs a strategy to address the very real threat of climate change. The longer we wait, the graver the risks - and the cost of averting them," said the Pew Center's Eileen Claussen.

Part of "Environmental Impacts" Series

Coastal and Marine Ecosystems and Global Climate Change: Potential Effects on U.S. Resources was prepared for the Pew Center by Victor S. Kennedy (University of Maryland), Robert R. Twilley (University of Louisiana at Lafayette), Joan A. Kleypas (National Center for Atmospheric Research), James H. Cowan, Jr. (Louisiana State University), and Steven R. Hare (International Pacific Halibut Commission). It is the eighth in a series of Pew Center reports examining the potential impacts of climate change on the U.S. environment. Other Pew Center reports focus on domestic and international policy issues, climate change solutions, and the economics of climate change.

A complete copy of this report and other Pew Center reports can be accessed from the Pew Center's web site, www.c2es.org/global-warming-in-depth/policy/reports/.

###



The Pew Center was established in May 1998 by The Pew Charitable Trusts, one of the United States' largest philanthropies and an influential voice in efforts to improve the quality of the environment. The Pew Center is an independent, nonprofit, and non-partisan organization dedicated to providing credible information, straight answers, and innovative solutions in the effort to address global climate change. The Pew Center is led by Eileen Claussen, the former U.S. Assistant Secretary of State for Oceans and International Environmental and Scientific Affairs.

Climate Change: Myths and Realities

Climate Change: Myths and Realities
Remarks of Eileen Claussen, President, Pew Center on Global Climate Change
Emissions Reductions: Main Street to Wall Street
"The Climate in North America"
New York, New York
July 17, 2002
Thank you very much. It's a pleasure to be here. I'd like to congratulate Swiss Re for its vision and initiative in pulling this conference together and I'd like to say how delighted I am that the Pew Center has been able to collaborate with you in shaping this wonderful program. And it's a great venue. Some of you, I imagine, have been visiting this museum since you were kids. And if you were like most kids, what probably impressed you was the dinosaurs. When I knew I'd be coming here to talk about climate change, I couldn't help but recall a very funny "Far Side" cartoon I'd seen once. A dinosaur is standing at a lectern before a group of other dinosaurs. And he says: "The picture's pretty bleak, gentlemen. The world's climates are changing, the mammals are taking over, and we all have a brain about the size of a walnut."

Now I don't know if it was climate change, a giant meteor, or puny brains that drove the dinosaurs to extinction - or maybe all three. But whatever the scientists ultimately decide, I think it really all boils down to this: the dinosaurs disappeared from the face of the earth because they couldn't adjust to new realities. And that lesson applies quite aptly, I think, to our topic today - the challenge of global climate change. I don't mean to imply that we are in imminent danger of being wiped off the face of the earth - at least, not on account of global warming. But climate change does confront us with profound new realities. We face these new realities as a nation, as members of the world community, as consumers, as producers, and as investors. And unless we do a better job of adjusting to these new realities, we will pay a heavy price. We may not suffer the fate of the dinosaurs. But there will be a toll on our environment and on our economy, and the toll will rise higher with each new generation.

What I'd like to do this morning is lay out some of the new realities thrust upon us by global warming. And I'd like to do that in part by examining - and, I hope, dispelling - some common myths about global warming. These are persistent myths, and I believe they are persistent for two reasons: first, because some people, including some people of influence, would rather deny the realities than face up to them; and second, because there are some modern-day dinosaurs who are not prepared to evolve. These relics thrived under the old realities, and they think the key to their survival is persuading us that these old realities still hold. Instead, I think, they are hastening their own extinction.

Before taking up some of these myths one by one, let me share with you a brief example. It comes from the Wall Street Journal. I have to say that on its news pages the Journal does a very good job with this issue. Its reporting on climate change is fair and it's insightful. But when it comes to the editorial page, I am afraid the Journal has distinguished itself as one of the most persistent and most powerful purveyors of climate change mythology. My example comes from an editorial that ran last July. It takes the form of a question. "Why," the Journal asks, "Why require the nations of this planet to spend the hundreds of billions of dollars necessary to reduce carbon dioxide and other emissions when we don't even know if the earth's climate is getting permanently hotter or if that temperature change is caused by human activity or if that change is even dangerous?" Before reading this, I didn't know it was possible to squeeze so many myths into a single sentence.

So allow me to begin unpacking them. Our first myth: We don't really know if the climate is changing or, if so, why. Here's the reality: there is overwhelming scientific consensus that the earth is warming, that this warming trend will worsen, and that human activity is largely to blame. Certainly you can find scientists who will argue otherwise. But these are the findings of the Intergovernmental Panel on Climate Change, a U.N. body that draws on the expertise of hundreds of climate scientists around the world. President Bush was among those who doubted the science, so he asked the National Academy of Sciences to undertake a special review. The NAS established a very well balanced panel, including some well-known skeptical scientists, and then came back with the very same conclusions: the planet is warming and we are largely responsible.

How significant is this warming? The earth's temperature has always fluctuated, but ordinarily these shifts occur over the course of centuries or millennia, not decades. The 1990s were the hottest decade of the entire millennium. The last five years were among the seven hottest on record. Scientists project that over the next century average global temperature will rise two to ten degrees Fahrenheit. A ten-degree increase would be the largest swing in global temperature since the end of the last ice age 12,000 years ago. In some communities, this is no longer a theoretical matter. The impacts are being felt right now. Just ask the people of Alaska, where roads are crumbling and homes are sagging as the permafrost begins to melt.

Which leads me to the second myth: Even if the earth is warming, that may actually help us more than hurt us. Here's the reality: In the short-term there will be winners and there will be losers. For instance, farms and forests will be more productive at some latitudes, but less productive at others. In the long term, though, any possible benefits from global warming will be far outweighed by the costs.

You may have heard about a new climate report that the United States submitted recently to the United Nations. The President tried to distance himself from the report, even though the White House had approved it, because some of his supporters didn't like its implications. But the "bureaucracy," as the President put it, actually did a very credible job of presenting what we know about the likely impacts of global warming here in the United States.

We face both increased flooding and increased drought. Extended heat waves, more powerful storms, and other extreme weather events will become more common. Rising sea level will inundate portions of Florida and Louisiana, while increased storm surges will threaten communities all along our nation's coastline. New York City could face critical water shortages as rising sea level raises the salinity of upstate aquifers and reservoirs. And a good chunk of lower Manhattan that's built on landfill could again be submerged. We can adjust to some of these things, if we're willing to pay the price. But many of the projected impacts are irreversible - when we lose a fragile ecosystem like the Everglades or Long Island Sound, it can never be replaced.

Let's turn now to a third myth: There's so much uncertainty - about the science, about the economics - that we need to wait for better information before we can decide how to respond. The reality is that there are several very compelling reasons that we must begin to act right now - and uncertainty itself is one of them.

It's important to understand the long-term nature of this challenge. There's a lot of inertia in the system, in both the economy and the climate, and overcoming it is going to take time. The greenhouse gases we've already placed in the atmosphere will continue to warm the planet for many decades if not centuries. Right now, there is about 40 percent more carbon dioxide in the atmosphere than there was at the dawn of the Industrial Revolution. The CO2 concentration is projected to reach twice the pre-industrial level by the middle of this century. This doubling of CO2 is the scenario most scientists have relied on in projecting the likely impacts of global warming. But here's what's really troubling: If we continue with business as usual, by the turn of the century greenhouse gas concentrations will be approaching three times the pre-industrial levels. In other words, we may be facing consequences far more severe than those already projected.

In order to stabilize concentrations anywhere within this range - two to three times the pre-industrial level - we must significantly reduce greenhouse gas emissions in the decades ahead. That will require major new technologies. Developing those technologies and turning over the existing capital stock will take time. We need to figure out the right mix of approaches to move us to a climate-friendly economy as cost-effectively as possible. And we'll do a better job at that if we allow ourselves time to learn by doing. All of these are reasons we need to start now.

But perhaps the most compelling reason is uncertainty itself. Uncertainty cuts both ways. It's possible the impacts of warming will be less severe than projected. They could also be worse. For instance, most of our computer modeling assumes a linear relationship between rising temperatures and impacts: as the planet warms, the impacts grow proportionately worse. But there's evidence that some parts of the climate system work more like a switch than a dial. That is why some scientists worry more about the non-linear event - the catastrophic event - like the breakup of the West Antarctic ice sheet or the collapse of the Gulf Stream. So, for me, uncertainty is hardly a reason to delay action. Quite the contrary - it's a powerful argument for acting right now.

Myth number four: We can't afford to address climate change. Well by now you can probably tell that as far as I'm concerned, we can't afford not to address climate change. But let's take a closer look at the cost question. Let's start with the numbers. They're all over the place. For every study you can cite showing that a serious climate program will mean certain economic ruin, I can cite one showing that it will be an economic boon. The point is: You shouldn't believe any of them. There does not yet exist an economic model capable of simulating the real costs and benefits of significantly reducing our greenhouse gas emissions.

Over the past few years, we have been working with top economists from some of our leading universities to methodically dissect the models and expose their weaknesses. Most models, for instance, do a poor job of projecting how rising energy prices will lead producers or consumers to substitute other goods and services; how price signals will drive new technology and innovation; or how businesses will respond to changes in policy. The models also have a difficult time weighing the near-term costs of emission reduction against the long-term benefits of avoiding climate change impacts. Some projections look only at the cost side and don't even consider the benefits. Our goal now is to build a better model, and we're getting close. But until then, I suggest you be very wary of anyone claiming to know precisely what it will cost to tackle climate change over the long term.

There is another source of data that I believe is instructive, though, and that is the experience of companies that are taking serious steps right now to reduce their emissions. A growing number of companies are voluntarily committing themselves to greenhouse gas reduction targets. At last count, we had identified more than 40, most either based in the United States or with significant operations here. Some of you may have seen the television ads being run by BP touting its success. The company has cut emissions 10 percent below 1990 levels - eight years ahead of target - and now has pledged to keep them there at least until 2010. Alcoa is aiming to reduce its emissions 25 percent below 1990 levels by 2010. DuPont is aiming for a 65 percent reduction.

We recently studied several companies that have taken on targets and found that they are motivated by several things. They believe the science of climate change is compelling. They know in time the public will demand strong climate protections, and they can get ahead of the curve by reducing their emissions now. They want to encourage government policies that will work well for business. The companies also cited one other important motivation: To improve their competitive position in the marketplace. And that, in fact, has been the result. The companies are finding that reducing emissions also helps to improve operational efficiencies, reduce energy and production costs, and increase market share - all things that contribute to a healthier bottom line. I'm not going to argue that addressing climate change is necessarily profitable. But I think the evidence so far suggests that it is certainly affordable.

Finally, our fifth myth: Even if climate change is real, and even if addressing it is affordable, the issue is so big and so complex, and the threat is so far off in the future, we will never motivate people to do anything about it. As to whether we can get people to move fast enough, or far enough, I think the jury is still out. But the reality is: people are beginning to act. And some who may not be prepared to act will soon be forced to.

Exhibit A is Kyoto. You'll notice I've gotten this far without even mentioning the Kyoto Protocol, but that's not because it's no longer relevant. In fact, it's more relevant than ever. True, President Bush rejected Kyoto. But the result was even stronger support among other nations. The negotiations are now complete. Japan and the European Union have already ratified it. All that is needed to bring the treaty into force is for Russia to ratify, and odds are that will happen next year if not sooner. Now the U.S. may be out of Kyoto. But U.S. companies are not. Any company producing or selling in a Kyoto country - and that includes all of Europe - will soon know what it means to operate in a carbon-constrained world. U.S. business has a direct stake in ensuring that Kyoto, and any domestic requirements that flow from it, are implemented sensibly and fairly.

There are promising signs of action closer to home as well. The President's rejection of Kyoto not only helped save the Protocol - it elevated this issue in the United States. Climate change has become a political story and the press is keeping it alive. The recent report to the United Nations is a good example. The report contained no new information, it outlined no new policy initiative, and the administration made no announcement of it. Yet it made network news and page one of the Times.

In Congress, meanwhile, members of both parties suddenly seem eager to demonstrate their interest in climate protection. Nearly twice as many climate change bills were introduced in Congress over the past year as in the previous four years combined. The energy bill passed in April by the Senate includes two bipartisan climate provisions - one establishing a new office in the White House charged with developing a long-term climate strategy, the other establishing a system for tracking and reporting greenhouse gas emissions that is voluntary at first but after five years could become mandatory. These are only modest first steps, and there's no saying they will wind up in the final energy bill, if there is a final energy bill. But I think some form of reporting bill will probably be enacted by the end of next year. And some lawmakers are already looking much further down the road. Senators John McCain and Joe Lieberman, an interesting bipartisan duo, plan to introduce legislation later this year to cap greenhouse gas emissions in the United States and establish an economy-wide emissions trading system. It is, frankly, hard to imagine such legislation being enacted anytime soon. But the fact that it is even being drafted shows that this issue is taking on a new political potency.

For real action, though, you need to look at the states. At least two-thirds of the states have programs that, while not necessarily directed at climate change, are achieving real emission reductions. For instance, Texas and 13 other states have enacted renewable portfolio standards, requiring utilities to generate a share of their power from renewable sources. A growing number of states are tackling climate change head on. New York, for instance, just adopted a state energy plan that sets a goal of reducing emissions 10 percent below 1990 levels by 2020. The New England states have agreed to the same target as part of a compact with neighboring provinces in Canada. Some states are going beyond target-setting and establishing direct controls on carbon. New Hampshire recently became the third state to enact mandatory controls on carbon from power plants. And California, of course, is out ahead of everyone with a new law regulating carbon from cars and light trucks. The new law is headed straight to the courts. But whether or not it survives, it has already sent a powerful message: With or without Kyoto, and with or without Washington, there is growing support in the United States for getting serious about climate change.

So let's recap. Five myths: We don't know if the earth is warming or, if so, why. If it is warming, don't worry - climate change will do us more good than harm. With all this uncertainty, we just don't know enough to act. We can't afford to act. And even if we could, people will never be motivated enough to tackle a problem so big and so complex. And five realities: The earth is warming, largely because of human activity. In the long run, any benefits from warming will be far outweighed by the costs. There are plenty of reasons to start acting right now - and uncertainty is one of them. The companies that understand this are demonstrating that we can afford to do it. And people are in fact beginning to act - internationally, in statehouses, in corporate boardrooms, and maybe even in the U.S. Congress.

Let me add one more reality: The actions we are seeing today, while encouraging, are barely a start. The only way to keep our planet from overheating is to dramatically reduce emissions of carbon dioxide and other greenhouse gases. There are plenty of steps we can take right now, starting with a systematic effort to improve energy efficiency throughout the economy - in our cars, our factories, our offices and our homes. In generating electricity, we can substitute natural gas for dirtier coal and oil. We can expand the capacity of our farms and forests to soak up carbon from the atmosphere. And we can invest in similar efforts around the world. But these are all intermediate steps. In the long run we need to fundamentally transform the way we power the global economy. Our goal, over time, must be to steadily reduce our reliance on coal and oil and adopt clean sources of energy that can power our economy without endangering our climate. It is a tall order. In fact, it requires nothing short of a new industrial revolution.

I believe that to get this revolution going, four major forces must be brought to bear. The first is technology - or, more accurately, a vast array of new technologies: new fuels, new engines, new industrial processes, and new ways to generate electricity. The second major force is the marketplace, because only the marketplace can mobilize the investment, the productive capacity, and the ingenuity that will be needed. But the market will deliver only if it perceives a demand. And for that we must bring to bear a third force - the force of government. Government must signal the market that the time to start investing is now. It must set clear, enforceable goals, and it must provide sensible rules giving companies the flexibility to meet those goals as cost-effectively possible. And government will do that when the fourth and most critical force is brought to bear - the force of public opinion. That, I believe, is only a matter of time.

I'd like to elaborate just a bit on one of these forces, and that is the marketplace. The market, of course, helped create global warming - although the economists, I suppose, would say it was more a case of "market failure." The climate, as they say, is the quintessential "commons," the public good that is free to everyone, and therefore valued by no one. But even now that we understand its value, and the risks of continuing to overburden it, the market cannot possibly fix the problem of its own accord. It is simply incapable of factoring in the very long-term costs and benefits, of giving them sufficient weight, to drive the investments that are needed in the short-term. That is why government must give it direction. But given the right direction and the right incentives, harnessed instead of stifled, the market can be a very powerful force for climate protection.

Now if you are a business, or an investor, the market is the environment within which you operate. And as society comes to grips with climate change, the rules of the market will change. The climate will stop being free. There will be a cost for emitting carbon. From the business perspective, that will be the most important new reality. And it will require some adjustment. Those who understand that reality, and make the adjustment, will not only survive but thrive. Because in every change there is opportunity, and the rewards flow to those who seize it first. But by the same token, those who ignore this new reality and fail to adjust will pay the price. The market is a harsh arbiter. It will figure out quickly enough who's done a good job of managing their carbon risk, and who has not. If you want to make sure you're a market winner in the carbon-constrained world of the future, and not a loser, the time to start is now.

Those are some of the new realities we face, some of the realities we have brought upon ourselves. I think we would all be well advised to start adjusting to them. We have one advantage over the dinosaurs: our brains our bigger. Only time will tell whether we have the collective will to put all of that brainpower to work. Thank you very much.
Syndicate content