Block level weekly pollution estimates and distances for each pollutant were then averaged up to the tract and ZCTA levels using the population living within each block as a weighting factor.
The estimates do not include the number of deaths from indoor pollution, estimated to be another 3 million or so each year, the scientists said.
Such pollution estimates do not include the dangers associated with climate change, which is exacerbated by the carbon dioxide emissions from burning coal.
Ms. Chase said she expected Zipcar to change people's driving habits in ways that would reduce traffic and pollution, estimating that each Zipcar took 8 to 10 cars off the road.
Another, in March of this year, offers a new interpretation of a formula that could result in lower pollution estimates — and fewer permits.
One, in December 2017, instructs state and federal regulators not to second-guess companies' pollution estimates, which determine whether they must apply for permits.
The rigging of the VW emissions tests hid the reality of cars spewing 40 times the legal limit of nitrogen oxide, and pollution estimated to equal the UK's combined emissions for all power stations, vehicles, industry, and agriculture.
Each approach, however, has inherent limitations that restrict its use for producing local-scale pollution estimates.
