During 2020, global COVID-19 lockdowns resulted in a decrease in global NOx emissions. Because the amount of free tropospheric ozone is closely tied to NOx photochemistry, this reduction also produced a reduction of tropospheric ozone. This visualization presents the results of a study done by scientists at the Jet Propulsion Laboratory (JPL) to quantify this decrease. The scientists modeled the atmosphere from February to June 2020, and compared it to the “business as usual” case that would be expected in the absence of the lockdown. The result was an overall decrease of free tropospheric ozone of up to 5 ppb globally.
GCMD keywords can be found on the Internet with the following citation:
Olsen, L.M., G. Major, K. Shein, J. Scialdone, S. Ritz, T. Stevens, M. Morahan, A. Aleman, R. Vogel, S. Leicester, H. Weir, M. Meaux, S. Grebas, C.Solomon, M. Holland, T. Northcutt, R. A. Restrepo, R. Bilodeau, 2013. NASA/Global Change Master Directory (GCMD) Earth Science Keywords. Version 18.104.22.168.0