clm-658968e5e4b7710c
quantitative
Beijing began publishing real-time PM2.5 readings in 2013
Permanent project revision
Revision 2026-08-27-p1-quality-uplift · effective 2026-08-26
Superseded. A later revision exists: 2026-08-27-source-dating →
Full claim mapping over snippet, impact and lesson; sourced impact and lesson added; unverifiable PM2.5 figure pair withdrawn and replaced with the monitoring centre's own reported series; source dates recorded and the entry re-read.
sha256:792939f98bbf0031f4f51e0ce9ad62c84b177dc3bcf9ecdc42dfa2eec3db93c9
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clm-658968e5e4b7710c
quantitative
Beijing began publishing real-time PM2.5 readings in 2013
clm-0f149e2f6edc9044
quantitative
35 standard stations measuring six pollutants continuously
clm-48aa7becd965228d
quantitative
and — from 2016 — more than 1,000 compact sensors across communities and townships, backed by satellite remote sensing and laser radar
clm-856d48f684749027
quantitative
an analytical system that resolves around 125 components of PM2.5 to trace sources
clm-049637deb028dd27
descriptive
feeds a linkage model that forwards suspected pollution to enforcement departments
clm-8949cdf50d19cab6
quantitative
UNEP's 2019 review found Beijing's fine particulate pollution fell by 35% between 2013 and the end of 2017, and by 25% in the surrounding Beijing-Tianjin-Hebei region
clm-77183db29b82ae10
descriptive
credited coal-boiler controls, cleaner domestic fuels and industrial restructuring for much of it rather than the instruments
clm-a81c66dfbb2ac036
quantitative
The city's own monitoring centre reports the annual mean falling from 89.5 micrograms per cubic metre in 2013 to 27 in 2025, and heavily polluted days from 58 to one
clm-ccaeebf7b11f6633
quantitative
the latest source apportionment puts 57% of Beijing's PM2.5 on regional transport and the remaining 43% on local sources, led by vehicle and residential emissions
clm-ac727549a4d5e0d6
quantitative
The compact sensors arrived in 2016, three years after the decline began
clm-34556852de7e046c
descriptive
once apportionment puts most of the remaining particles on transport from outside the city, the work left is regional
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sha256:792939f98bbf0031f4f51e0ce9ad62c84b177dc3bcf9ecdc42dfa2eec3db93c9
src-89d5da7d0e10b635Independent review of two decades of air-pollution control in Beijing; source for the ~35% PM2.5 decline over 2013-2017 and the ~25% regional decline, both quoted by the Climate & Clean Air Coalition.
src-ec7e146ac8042367Independent account of the integrated network: created in 2016, using high-resolution satellite remote sensing and laser radar, with over 1,000 sensors distributed across the city.
src-3f3768226a3bbd4dQuotes the UNEP review's headline findings and attributes much of the reduction to coal-boiler controls, cleaner domestic fuels and industrial restructuring.
src-9dc84c1a1fa08b51Beijing Municipal Ecological and Environmental Monitoring Centre figures relayed by the state news agency: 35 standard stations and more than 1,000 compact sensors, ~125 PM2.5 components resolved, the regulation-monitoring-inspection linkage model, and the annual mean falling from 89.5 to 27 micrograms per cubic metre between 2013 and 2025.