The coronavirus pandemic had reduced global CO₂ emissions by two gigatonnes - approximately the equivalent of the net increase in carbon emissions since 2013. Despite the pandemic carrying on in 2021, CO₂ entering the atmosphere rebounded majorly in 2021 and is again approaching 2019 levels. Numbers released by the International Energy Agency show that the biggest fluctuation was linked to the change in oil use as virus lockdowns cut down on transportation. Oil is also the only major fossil energy source which hasn't fully recovered from its coronavirus low. Coal and gas use have already returned to their pre-pandemic levels.
Global carbon emissions, as well as global energy demand had increased in 2017 and 2018, mostly driven by China and the United States. Emissions flat-lined in 2019 as well as in 2014, 2015 and 2016. The coronavirus crisis led to the first significant annual decrease in global CO₂ emissions in recorded history, save a much smaller drop of 0.4 gigatonnes in 2009.