People north of Huai River live 3 years less
People born just north of China's Huai River — where coal heating caused heavy pollution — lived on average 3 years less than those born just south.
Where this was said
The Huai River: A Natural Experiment in Long-Run Pollution Damage
At 45:13 · chapter starts 43:55
Greenstone has always argued that the 'holy grail' of pollution research is long-run variation — not day-to-day fluctuations, but the kind of persistent difference that policy actually creates. The Huai River heating policy, which gave free coal to provinces north of the river and nothing to provinces south, with limited migration between sides, offered exactly that. [1] — Michael Greenstone "China's Huai River heating policy drew an arbitrary line across the country: free coal for the north, nothing for the south. Because migrat…" 43:50 Among roughly 40,000 people in urban areas within five degrees latitude of the river, people born just north lived about 3 years less than those born just south. In subsequent research, Greenstone extended the analysis to children born between 1975 and 1982: north-side children completed nearly a full year less of education and, observed as adults, earned 13% less. Greenstone calls this the first large-scale evidence on the impacts of long-run early childhood pollution exposure at the concentrations that prevail across much of Asia and sub-Saharan Africa today.
Huai River: 1 year less education north of river
Children born just north of China's Huai River — where free coal heating created persistent pollution — completed almost one full year less of education than children born just south.
Huai River: 13% lower adult earnings north of river
Adults born just north of the Huai River — exposed to coal smoke from China's heating policy — earned on average 13% less than those born just south.
Understating pollution losses by 50%
Michael Greenstone argues that because we have ignored the cognitive costs of pollution, we have been understating total losses from air pollution by about 50%.
Beijing PM2.5 fell from 100+ to ~50 micrograms
Beijing's particulate matter levels fell from over 100 micrograms per cubic meter in 2013 to just over 50 by 2018 — a dramatic improvement China achieved faster than the US ever did after the Clean Air Act.
China's Dramatic Air Quality Turnaround
Beijing's particulate matter levels fell from over 100 micrograms per cubic meter in 2013 to just over 50 by 2018. Greenstone estimates a child born in 2018 will live 1.4 years longer than one born in 2013 — a pace of cleanup the US never matched after its own Clean Air Act.
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