Many states have reached across borders to collaborate on efforts to address climate change. Across the United States and Canada, multi-state climate initiatives have been designed and implemented to reduce greenhouse gas emissions and spur public and private investment in clean energy, energy efficiency, and sustainable infrastructure. Multi-state initiatives can be more effective and efficient in reducing greenhouse gases across a broad area because they provide predictable rules and avoid duplicative processes. Click on the initiatives below to learn more:
Summary: The Regional Greenhouse Gas Initiative  (RGGI) is the first U.S. cap-and-trade program to reduce carbon dioxide (CO2) emissions from the power sector. Currently, the program is composed of Connecticut, Delaware, Maine, Maryland, Massachusetts, New Hampshire, New York, Rhode Island, and Vermont. Since 2009, RGGI has set a cap on CO2 emissions from power plants throughout the region. To comply, regulated entities trade emission allowances. The program is administered through RGGI, Inc., but individual state governments have enforcement authority. Following a comprehensive program review in 2012 - 2013, RGGI adjusted the program cap to achieve an annual 2.5 percent emissions reduction each year between 2014 and 2020 from estimated 2012 levels.
Each covered source is required to surrender emission allowances equal to their emissions over a three-year control period, with a partial surrender obligation due each year. The first control period covered 2009 – 2011 and covered the nine current states plus New Jersey. New Jersey withdrew from the program beginning with the second control period.
History: On Dec. 20, 2005, the governors of seven Northeast states announced the creation of the Regional Greenhouse Gas Initiative (RGGI) . The governors of Connecticut, Delaware, Maine, New Hampshire, New Jersey, New York, and Vermont signed a Memorandum of Understanding  (MOU) agreeing to implement the first mandatory U.S. cap-and-trade program for carbon dioxide.
On Jan. 18, 2007, Massachusetts Gov. Deval Patrick signed the RGGI MOU, thereby committing his state to join RGGI. On Jan. 30, Gov. Donald Carcieri announced that Rhode Island would join RGGI. On April 6, 2006, Maryland Gov. Robert L. Ehrlich Jr. signed into law the Healthy Air Act.  The bill required the governor to include the state in RGGI by June 30, 2007. Maryland became the 10th official participating state in April 2007 with Gov. Martin O'Malley's signing of the RGGI MOU.
In May 2011, New Jersey  announced in that it would be exiting the program, a move that was complete by the beginning of 2012. The RGGI program underwent a prescribed program review in 2012, and states adopted an updated model rule in 2013. A key focus of the review was a dramatic drop in covered emissions from 2005. This was a result of market forces and decreased economic activity making emissions much lower than the cap. Member states agreed to lower the cap from 165 short tons of CO2 in 2013, to 91 million short tons in 2014. The cap decreases annually by 2.5 percent until 2020, then remains constant. RGGI is undertaking another program review in 2016. 
According to the 20 14 RGGI Monitoriing Report , the annual average carbon dioxide emissions from RGGI electric generation sources were 35.7 percent lower in 2012-2014, compared to the base period of 2006-2008. Additionally, the annual average carbon dioxide emissions rate and the electric generation output for these sources decreased 19.8 percent and 15.8 percent respectively, as compared to the 2006-2008 base period. Relative to 2005 emissions, more than 45 percent reductions in CO2 emissions are projected from the electric power sector by 2020 . A study  released in July 2015 shows that RGGI has resulted in net economic benefits of $1.3 billion to participating states during the second compliance period (2012-2014). These benefits come in large part from the use of auction proceeds to address state policy objectives related to energy efficiency, renewable energy, and customer bill reductions.
Summary: The Western Climate Initiative  (WCI), was initially formed as a collaboration of jurisdictions working together to identify, evaluate, and implement emission-trading programs at a sub-national level. In November 2011, WCI transitioned into WCI, Inc. , a nonprofit corporation that provides administrative and technical assistance to support the implementation of state and provincial greenhouse gas emission trading programs. The State of California and the Provinces of British Columbia, Ontario, and Quebec are current participating jurisdictions.
Under the auspices of WCI Inc., California  and Quebec linked their cap-and-trade programs on Jan. 1, 2014. WCI, Inc. manages the Compliance Instrument Tracking Service System , administers allowance auctions, and facilitates independent market monitoring of allowance auctions. As of 2016, the state of California and the provinces of British Columbia, Ontario, Quebec, and Manitoba continue to work together through the WCI to develop and harmonize their emissions trading program policies.
History: On Feb. 26, 2007, Governors Janet Napolitano of Arizona, Arnold Schwarzenegger of California, Bill Richardson of New Mexico, Ted Kulongoski of Oregon, and Christine Gregoire of Washington signed an agreement establishing the WCI, a joint effort to reduce greenhouse gas emissions and address climate change. Later, the governors of Utah and Montana, as well as the premiers of British Columbia, Manitoba, Ontario, and Quebec joined as partners. An additional 14 jurisdictions joined as observers, including Alaska, Colorado, Idaho, Kansas, Nevada, and Wyoming in the United States; Nova Scotia and Saskatchewan in Canada; and Baja California, Chihuahua, Coahuila, Nuevo Leon, Sonora, and Tamaulipas in Mexico.
The WCI was built on the efforts of individual participating states and provinces, as well as two regional predecessors: the Southwest Climate Change Initiative  of 2006, consisting of Arizona and New Mexico, and the West Coast Governors’ Global Warming Initiative , consisting of California, Oregon, and Washington.
According to the the initiative’s MOU, WCI Partners agreed to jointly set a regional emissions target and establish a market-based system—such as a cap-and-trade program covering multiple economic sectors—to help meet this target. In August 2007, the WCI announced its regional, economy-wide greenhouse gas emissions target of 15 percent below 2005 levels by 2020, or approximately 33 percent below projected business-as-usual levels. The regional target was designed to be consistent with existing targets set by individual member states and did not replace these goals. Emissions covered by the target included the six primary greenhouse gases identified by the United Nations Framework Convention on Climate Change (UNFCCC): carbon dioxide, methane, nitrous oxide, hydrofluorocarbons, perfluorocarbons, and sulfur hexafluoride.
In September 2008, the WCI released Design Recommendations for a Cap-and-Trade Program , with an envisioned program start date of January 2012. The program was designed to cover emissions from the electricity sector and large industrial and commercial sources from 2012, and to also cover emissions from transportation and other residential, commercial, and industrial fuel users beginning in 2015. In July 2010, the WCI Partners released the Design for the WCI Regional Program , a comprehensive strategy that built upon the recommendations released in 2008 to reduce greenhouse gas emissions, stimulate development of clean-energy technologies, create green jobs, increase energy security, and protect public health. The strategy provided the roadmap to deliver on the regional greenhouse gas emission target established in 2007, and represented the culmination of two years of work by seven U.S. states and four Canadian provinces.
Summary: The Midwestern Greenhouse Gas Reduction Accord (MGGRA) is a commitment launched in 2007 by the governors of six Midwestern states and the premier of one Canadian province to reduce greenhouse gas emissions through a regional cap-and-trade program and other complementary measures. Members of MGGRA are not currently pursuing their greenhouse gas goals through the accord.
History: On Nov. 15, 2007, the governors of Illinois, Iowa, Kansas, Michigan, Minnesota, Wisconsin, as well as the premier of Manitoba, signed the Midwest Greenhouse Gas Reduction Accord (MGGRA) as full participants. The states of Indiana, Ohio, and South Dakota joined the agreement as observers. On November 27, 2008, the province of Ontario also joined as an observer. Under the accord, members agreed to establish targets for greenhouse gas emission reductions that were consistent with states’ targets, and to complete the development of a proposed cap-and-trade agreement and model rule. This resulted in the release of a final model rule in April 2010, which detailed a cap-and-trade program designed to reduce greenhouse gas emissions by 20 percent below 2005 levels by 2020, and 80 percent below 2005 levels by 2050. After releasing the final model rule , the states and province in MGGRA did not continue to pursue their greenhouse gas goals through the accord.
Summary: A diverse array of states and provinces launched North America 2050: A Partnership for Progress (NA2050) in March 2012. NA2050 participants committed to policies to move their jurisdictions toward a low-carbon economy while creating jobs, enhancing energy security, protecting public health and the environment, and demonstrating climate leadership. NA2050 was a multi-state, multi-regional collaborative working toward mitigating the impacts of climate change and advancing clean energy, carbon capture and sequestration , and industrial energy efficiency benchmarking . The Center for Climate and Energy Solutions (C2ES) served as one of five nonprofit advisory groups for the NA2050 partnership. NA2050 became inactive in 2014.
History: NA2050 was the successor to the 3-Regions Initiative, a collaboration among members of the three North American regional cap-and-trade programs: the Midwestern Greenhouse Gas Reduction Accord, the Regional Greenhouse Gas Initiative, and the Western Climate Initiative.
NA2050 was composed of six working groups, which collectively facilitated dialogue among governments, private sector entities, NGOs, and academic institutions. Each working group provided topical support focusing on the different aspects of the energy, climate, and economic challenges facing the participating jurisdictions. C2ES was lead advisor to the Industry 2050 Working Group and the Sequestration Working Group.
Summary: Established in 2008, the Pacific Coast Collaborative  (PCC) is a cooperative agreement among the leaders of Alaska, British Columbia, California, Oregon, and Washington to leverage clean energy innovation and low-carbon development to reduce the effects of climate change on the regional economy. Together, the PCC jurisdictions comprise 54 million residents, with a total gross domestic product of $3 trillion. Through the PCC, leaders from participating jurisdictions coordinate, propose, and adopt policy frameworks aimed at generating investments in renewable energy, climate resilience, low-carbon transportation infrastructure, and environmental conservation. Unlike its larger regional counterparts such as the Midwestern Governors Association,  the PCC is focused on low-carbon development, while emphasizing coordination of state-level climate policies to achieve the broader goals presented in PCC agreements.
History: The PCC was established on June 30, 2008, to strategically confront the economic risks posed by climate change to the Pacific Coast region. The original agreement signaled a commitment by each jurisdiction to deploy more renewable energy and to promote environmental and coastal conservation. On Feb. 12, 2010, the PCC issued Vision 2030,  outlining the group’s efforts to lead North America in clean energy innovation, climate adaptation, and sustainable infrastructure. The plan centers on increased deployment of solar, wind, geothermal, hydro, and tidal energy, as well as projects geared toward widespread adoption of energy-efficient technology. It introduces a plan to develop high-speed rail infrastructure between San Diego and Vancouver, B.C., as well as establish fuel-efficiency benchmarks and permitting standards for vehicles. In addition, the plan acknowledges the important role of a regional network of climate change scientists, researchers, and policy makers in building resilience to climate change in the region whilst offering new economic opportunities.
On Nov. 14, 2012, the PCC announced a joint effort  between California, Oregon, Washington, and the province of British Columbia to enable investments in sustainable infrastructure projects through the creation of the West Coast Infrastructure Exchange . By reducing costs through the bundling of projects, partnering with innovators in other regions, and connecting public entities with private capital, the exchange will help the region meet infrastructure investment needs estimated at $1 trillion over the next 30 years.
On Oct. 18, 2013, the PCC signed the Pacific Coast Action Plan on Climate and Energy , a nonbinding agreement to align climate regulations and market-based measures in each member jurisdiction. The plan presents a number of policies  to promote clean energy deployment, carbon pricing, revised regional greenhouse gas reduction targets for 2030, and low-carbon transportation. Several provisions highlight the need for regional cooperation to reduce greenhouse gas emissions, such as those supportive of an integrated electrical smart-grid to support increased renewable generation, and the continued deployment of high-speed regional rail line along the Pacific Coast.
Summary: The Transportation Climate Initiative  (TCI) is a collaboration of twelve Northeast and Mid-Atlantic jurisdictions launched in 2010, to develop a clean energy economy and reduce greenhouse gas emissions in the transportation sector. The TCI aims to expand safe and reliable transportation options, attract federal investment, lower transportation costs, improve overall air quality and public health, and mitigate the transportation sector's impact on climate change. The TCI consists of Connecticut, Delaware, Maine, Maryland, Massachusetts, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, Vermont, and the District of Columbia. Transportation currently accounts for roughly 40 percent of greenhouse gas emissions in the U.S. Mid-Atlantic and Northeast.
History: On June 16, 2010, eleven Mid-Atlantic and Northeast states and the District of Columbia announced a Declaration of Intent for the TCI. The jurisdictions established the Transportation, Energy, and Environment Staff Working Group to direct the initiative's planning and seek public and private funding for projects. The Georgetown Climate Center facilitated the initial meeting of the TCI and continues to support the effort.
On June 7, 2011, the TCI jurisdictions agreed to work cooperatively in support of sustainable communities, through the enhancement of transportation policies that combined smart growth land use planning with sustainable development concepts. In support of this agreement, the Georgetown Climate Center and Rutgers University’s Bloustein School of Planning and Public Policy produced research papers  examining 11 potential indicators that could be used to measure progress towards sustainable communities.
On Oct. 19, 2011, the TCI jurisdictions announced the creation of the Northeast Electric Vehicle Network , bringing together companies, organizations, and jurisdictions to lay the groundwork, both in terms of infrastructure and planning, for the region to lead in the deployment of electric vehicles. Since its creation, the Northeast has seen an increase in the number of public electric vehicle charging stations and vehicle deployment, with the TCI also active in providing planning and policy support to help states become more electric vehicle ready.