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NASA Shares Worrying Images Of US East Coast Engulfed By Smoke From Canadian Wildfires
The air quality index measures PM2.5, less than 2.5 microns particles, to determine the intensity of air pollution in cities.
Canadian wildfires spark air quality alert for parts of Minnesota, Twin Cities metro
The Minnesota Pollution Control Agency has issued an air quality alert for a number of areas in the state, including the Twin Cities metro, effective from noon to 9 p.m. Friday, May 31.  Air ...