Fig. 4: Impact of WFPM on ground level temperature of metropolitan areas in northeast US.

Mean daily temperature, T, obtained based on meteorological data in New Brunswick, NJ (a) or Central Park, NYC (b) on June 7 (red filled bars) and the reference27 smoke-free period (May 30–June 1 and June 12–14; blue dotted bars). Error bars show the standard deviation of the mean daily temperature during the reference period.