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In mid-March 2020, Shelter-in-Place orders were enacted across the San Francisco Bay Area to slow the spread of the worsening COVID-19 pandemic. All but essential businesses were closed, resulting in a 70% reduction in automotive traffic. Cars that would normally be driven and parked in large surface lots or moving between work and home on highway surfaces remained idled.  Consequently, fine particulate and ozone pollution concentrations in the Bay Area were 30% lower from March through June when compared to previous years. Scientists at NASA Ames Research Center are using satellite thermal data from the Landsat and ECOSTRESS sensors to investigate related environmental changes in the Bay Area urban landscape since the COVID-19 pandemic began.  NASA remote sensing data are showing that decreases in air pollution levels also increased solar radiation fluxes to the ground surface since early 2020.  However, having cleaner air and less aerosol pollution over the cities meant that the heat re-emitted during the daytime from dark asphalt and cement surfaces did not stay trapped near the ground as long, cooling the urban environment as it was dissipated relatively rapidly.  As a result, all large parking lots, highway corridors, and commercial rooftops were measured at 10-15 degrees Fahrenheit cooler during the March to May period of 2020 compared to previous years.