The U.S. has not yet passed national legislation on climate change, but there have nonetheless been many climate change initiatives throughout the country. Northeast states established the Regional Greenhouse Gas Initiative (RGGI) in 2005, and in September 2006, California adopted a long-term goal to reduce its emissions by 80 percent by 2050. Other states and more than 350 cities are developing their own policies and commitments to reduce emissions, reduce energy use, and switch to renewables. And there are no fewer than seven legislative proposals coming before the 110th Congress.
So what will it take to significantly reduce U.S. emissions? U.S. emissions are usually considered in very broad terms, from power plants to vehicles to building energy use. But the real picture is a lot more complex. GHG emissions -- where they come from, and who generates them -- vary significantly from state to state, region to region, and from country to country at the global level.
Climate change policy has been evolving for years, but comprehensive GHG emissions data is relatively new. WRI's report, Navigating the Numbers, shows how important data is to international global warming policy. These articles on our Web site hope to do the same for emerging U.S. policies.
Consider this: in terms of emissions, every U.S. state is equivalent to an entire country, some small and some large. For instance, Texas, the largest emitting state, is equivalent to Canada, and Vermont, the smallest state in terms of emissions (besides Washington D.C.), is the same as Tajikistan. When combined, the 48 contiguous states are the equivalent of six major emitting countries.
State/country equivalencies are approximations intended for illustrative purposes; for some states, there may be several countries whose emissions may be similar and vice versa. Source: Climate Analysis Indicators Tool, World Resources Institute
What does that mean for U.S. climate change policy? For starters, each state has its own unique circumstances with respect to its GHG emissions and its capacity to reduce them. In that sense, federal and U.S. state policies are analogous to global efforts under the UN Framework Convention on Climate Change (UNFCCC) and the Kyoto Protocol, which refer to countries' common but differentiated responsibilities.
Second, regardless of federal action, states can make a significant global difference. Each state can reduce its emissions on a scale equivalent to at least one member of the Kyoto Protocol. Acting together, states could reduce emissions on a scale equal to a major developed or developing country. That said, there is no doubt that a comprehensive U.S. policy will be needed to reduce emissions on the scale required.
How This Map Was Made
WRI created this map using 2001 state-level GHG emissions from the Climate Analysis Indicators Tool (CAIT). State/country equivalencies are approximations intended for illustrative purposes. For more information, contact