Climate Compass Blog

Climate Change: "Unequivocal"

The following first appeared as a "Letter to the Editor" in today's Washington Post.

In his Feb. 21 op-ed column, "Global warming advocates ignore the boulders," George F. Will concluded, incorrectly, that the Earth isn't warming. Mr. Will referred to climate scientist Phil Jones, who said that the planet did warm from 1995 to 2009 but not "at the 95 percent significance level." But Mr. Jones also cautioned that 15 years is too short to expect statistical significance. That is why climate norms -- such as the "normal" daily temperatures that forecasters show on the local news -- are 30-year averages. The Post's readers might be interested to know, therefore, that the global warming trend from 1980 to 2009 -- a little over 1 degree Fahrenheit -- is statistically significant at the 99.9999 percent level.

Climate scientists have always stated clearly that it takes decades to detect a change in the climate, so why focus on just the last 15 years?

From its own reading of the peer-reviewed literature, the National Academy of Sciences concluded, "It is unequivocal that the climate is changing, and it is very likely that this is predominantly caused by the increasing human interference with the atmosphere. These changes will transform the environmental conditions on Earth unless counter-measures are taken."

Separating IPCC from Climate Science

This week, the National Journal Experts Blog asks: Can a U.N. probe calm the climate science storm?

In considering what should be done in light of recent revelations about aspects of the IPCC report, it is critical to distinguish between two different issues.  One has to do with the IPCC itself.  And yes, it is clear that here reforms are in order. The IPCC needs to clarify what sources can be cited in its reports, that all sources are properly verified, and that these guidelines are enforced.  Because of the important role the IPCC report plays in international discussions, the standard for accuracy and reliability of everything it issues must be very high. The independent review announced by UNEP and a transparent discussion about these issues at the next IPCC plenary is a necessary and welcome step.

The second issue relates to our basic understanding of climate science.  Here I think the answer is equally clear.  None of what we have recently heard or read changes the basic scientific consensus that human activities have increased greenhouse gases in the atmosphere, that these greenhouse gases have raised temperatures (and the more we put into the atmosphere, the more temperatures will increase), that sea level has risen and ice cover declined as a result, and that unless we act now to slow future emissions, we should expect these changes to get worse over time.

The body of scientific evidence behind these concerns has developed and grown over decades of research.  It is reflected in assessments by the National Academy of Sciences going as far back as the 1970s.  And it is reflected in the IPCC’s physical science assessment, which remains above reproach three years after its release. 

Weather vs. climate, and what a difference a few degrees can make

There seems to be some confusion out there about weather vs. climate.  For example, a Virginia Republican Party video urged citizens to call their Congressmen and tell them how much global warming they got during the big snowstorm a couple of weeks ago. But that doesn’t really make any sense.  In simple terms, weather determines whether you need to take an umbrella with you today; climate determines whether you need to own an umbrella.  Weather determines whether you need your down coat today; climate determines whether you need to own a down coat.  Weather determines whether you turn on your air conditioning unit today; climate determines whether you own an air conditioner.  Weather determines whether the plants in your garden have a good day; climate determines what plants will likely thrive in your local environment. 

Climate is the long-term average of weather.  Weather changes all the time; climates are generally fairly stable, allowing us to make long-term decisions based on the notion that the future climate will be like the past.  One unusual weather event does not mean the climate is changing. But many unusual weather events could mean the climate is changing. And climate change will mean that on average, the weather we will have in the future will be different from what we had in the past.   That could even mean that record-breaking snowfall events happen more and more often in Virginia and Washington, D.C.

Alaska Demonstrates a Bipartisan Approach to Climate Change is Possible

ANCHORAGE - "Hello.  I'm a Republican, and I believe in climate change."  These words opened a presentation at the Alaska Forum on the Environment and indicate that, here in Alaska, issues surrounding climate change have often transcended the partisanship that sometimes dominates the issue 3,000 miles away in Washington.

This bipartisanship has evolved because probably no place in America is the evidence of climate change more clearly on display than in Alaska.  Climate change’s leading edge is in the Arctic, and temperatures in Alaska have risen 4 degrees or even more depending on location.  With warming and its impacts visible to all and being increasingly analyzed on a local level, discussions of climate change, especially as it relates to adaptation, take on a tone all too unfamiliar inside the Beltway.

Yvo de Boer Announces Resignation

If there was going to be a fall guy for the chaos that was Copenhagen, Yvo de Boer was the natural choice.

As the executive secretary of the U.N. climate secretariat – one whose own profile has risen along with that of the climate issue – Yvo is closely associated in many minds with the perceived failure of Copenhagen. With parties’ confidence in him at an all-time low, it was no surprise that he announced today he would be departing July 1.