A new study found that Earth experienced some fever in 2020, in part due to cleaner air coming from the pandemic closure.
For a short time, temperatures in some places in the eastern United States, Russia, and China were up to half or two-thirds of a degree (.3 to .37 degrees Celsius) warmer. This is due to the reduction of soot and sulfate particles from the car’s exhaust and coal combustion, which normally cool the atmosphere temporarily by reflecting the sun’s heat, according to Tuesday’s study in the journal Geophysical Research Letters . reported.
Overall, the planet was about 0.05 degrees (0.03 degrees Celsius) warmer during the year, because the air had fewer cooling aerosols, which unlike carbon dioxide is the pollution you can see, according to the study.
“Clean air can warm the planet because this pollution (soot and sulfate) causes a cooling” that climate scientists have known for a long time, said study lead author Andrew Gettelman, a scientist atmospheric of the National Center for Atmospheric Research. His calculations come from comparing the time of 2020 with computer models that simulated a 2020 without reducing pollution from pandemic blockages.
This effect of temporary warming of fewer particles was stronger in 2020 than the effect of reducing carbon dioxide emissions that traps heat, Gettelman said. This is because carbon stays in the atmosphere for over a century with long-term effects, while aerosols stay in the air for about a week.
Even without the reduction of refrigeration aerosols, global temperatures in 2020 were already flirting with the annual heat record due to the burning of coal, oil and natural gas, and the aerosol effect may have been enough to help convert -the hottest year in NASA system measurements, said Gavin Schmidt, a NASA climate scientist who was not part of the study, but confirmed other research.
“Clean air warms the planet a bit, but it kills far fewer people with air pollution,” Gettelman said.
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