A satellite image showing nitrogen dioxide emissions — which primarily come from cars, trucks, buses, and power plants — in February 2019, 2020, and 2021. While February 2019 has some hot spots near Chicago, the 2020 and 2021 maps are nearly identical. Maps from NASA.

A satellite image showing nitrogen dioxide emissions — which primarily come from cars, trucks, buses, and power plants — in February 2019, 2020, and 2021. (NASA)