https://www.sciencedaily.com/releases/2020/07/200729114809.htm

"Without distracting from the most important priority -- which is clearly the health and well-being of people and communities -- the current easing of the human footprint is providing a unique window into the impacts of humans on the environment, including a number of questions that are critical for effective public policy," said lead author Noah Diffenbaugh, the Kara J Foundation Professor at Stanford's School of Earth, Energy & Environmental Sciences.

For example, the question of how much electrifying the vehicle fleet will improve air quality has until now relied heavily on theoretical arguments and computer models. The scale of recent emissions reductions, however, provides an opportunity to use atmospheric observations to check just how accurate those models are in simulating the impact of pollution-reduction interventions such as electric vehicle incentives.