WASHINGTON, D.C.—Which countries have emitted the most greenhouse gases? The quick answer is, “It depends.” A more definitive response is tougher than you may expect. Many factors inform the answer.
What time frame are you considering? Do you want to count cumulative emissions of a country over a long period of time, or only look at current annual emissions? And do you include emissions and removals from things like land use change and forestry? Or perhaps you want to know whether and when a country’s emissions have peaked?
Top emitters remain dominant—with a few notable changes
The world now pumps 40 times more greenhouse-gas (GHG) emissions into the atmosphere than we did back in 1850. While emissions have increased dramatically over this time, those responsible for the largest shares of emissions haven’t changed as much as one might expect.
Seven countries have consistently been among the top emitters on an annual basis and have driven emissions growth since 1850—namely the United States, the United Kingdom, Germany, France and Russia, and more recently India and China.
In comparison, if you rank countries from the largest emitters to smallest, three-quarters of the 50 lowest-emitting countries in 2014 are the same countries as in 1850.
A few countries stand out for the significant changes in rank they have experienced. Most of the biggest jumps are observed in oil and gas producing countries—almost all the countries with the largest increase in rank have petroleum products as main export.
At the same time, the breakup of the Soviet Union contributed to major declines in Lithuania, Tajikistan, Latvia, Moldova and Georgia.
Perhaps the most important takeaway is how consistent the top 10 emitters have been over the years. Six countries or blocs that were top emitters in 1850 remain so over 160 years later—the European Union, China, Germany, India, Russia and the United States.
1990-2014: Emissions continue to rise
Despite growing international concern over climate change, global emissions have continued to rise steadily.
The world’s total emissions have increased by 31 percent—including emissions from land use, land-use change and forestry—between 1990 and 2014.
Growth has been driven by major economies, such as China, which surpassed the United States as the world’s largest emitter in 2005, although the US remains the largest emitter in cumulative terms.
While many of the largest emitters in 1990 had fallen back a bit by 2014, Iran, Saudi Arabia, South Korea, Pakistan and Nigeria jumped ahead by at least 10 places over those 25 years, landing them among the top 20 largest annual emitters in 2014.
Countries’ GHG emissions per capita tells a different story
Developing countries have seen significant emissions growth in recent years, but in per capita terms, the picture is much different.
For instance, while India’s overall emissions are climbing upward, their per capita emissions have stayed well below the other top emitters; the United States’s per capita emissions are currently more than seven times that of India.
However, per capita emissions of other emerging economies like Indonesia, China and Iran are creeping upward and have exceeded those of some developed countries, as well as the average per capita emissions of the European Union.
49 countries have peaked emissions; list keeps growing
The World Resources Institute analysis finds that 49 countries were able to peak their emissions by 2010 and four more are expected to peak by 2020.
According to countries’ climate commitments under the Paris Agreement, seven of the current top 10 emitters (China, the United States, Russia, Japan, Brazil, Germany and Mexico) have peaked or have commitments to peak their emissions by 2030.
Some major emitting countries like the United Kingdom, France, Brazil, Spain and Canada have been able to sustain their economic growth and at the same time peak or even decrease their level of emissions. The fact that a quarter of all countries’ emissions have peaked their emissions is encouraging.
Peaking is just the first step toward making deep, rapid emission reductions necessary to achieve an emissions trajectory consistent with long-term low carbon future.
Countries must make and achieve commitments to peak their emissions as soon as possible, set their peaks at lower emissions levels and commit to a significant rate of emissions decline after peaking.