Largest global emitters of carbon dioxide by country 2019

In 2019, China was the biggest emitter of fossil fuel carbon dioxide (CO2) emissions. With a share of almost 30 percent of the world’s total CO2 emissions that year, this was roughly twice the amount emitted by the second largest emitter the United States.

Cumulative emissions

Although China currently emits the highest levels of CO2 annually, it has emitted far less than the United States over the past three centuries. Cumulative carbon dioxide emissions in the U.S. reached 367 billion metric tons by 2018. Since the birth of the Industrial Revolution more than 200 years ago, cumulative global CO2 emissions have increased dramatically. However, emissions started to increase more rapidly as of the 1960’s.

Impact of COVID-19 on emissions

Throughout history, major events such as wars and recessions have caused emission levels to fall. In 2020, COVID-19 led to a drop in emissions as governments enforced strict lockdowns. Travel bans around the world meant the transportation sector experienced significant emission reductions. By April 2020, aviation emissions had fallen 60 percent, relative to annual mean daily emissions in 2019.