Creating no-congestion zones in urban downtowns reduces air pollution.

NO2 tells a slightly different story. It dropped more than 20% across the whole metro area in 2025, but lower Manhattan fell only slightly more than the outer boroughs, so we can’t pin that decline on congestion pricing. Region-wide policies appear to be doing most of that work.

PM2.5 inside the zone fell by about 1.4 μg/m³ beyond what comparison sites across the city saw, a modest but significant effect we can mostly attribute to the policy. On the second, we found no significant spillover. Nearby sites in the Bronx and Queens showed no statistically meaningful increase.

New paper in ES&T Letters: the first full-year look at what NYC congestion pricing did to air quality. Led by the brilliant Polina Goldberg, we combined 15 roadside PM2.5 monitors with TROPOMI NO2 to ask if air in the Congestion Relief Zone got cleaner, and did pollution just move next door?

Looking forward to this event!