Air Pollution Concentration in Ulaanbaatar (2002-2026)

Monthly average PM2.5, PM10 and sulphur dioxide (SO₂) concentrations in Ulaanbaatar from 2002 to 2026, averaged across the city monitoring stations that reported each month (of 17 stations NSO lists). PM2.5 peaked at 0.622 mg/m³ in January 2013, PM10 at 0.836 mg/m³ in January 2012 and SO₂ at 0.216 mg/m³ in January 2021.

Air Pollution Concentration in Ulaanbaatar (2002-2026)

Methodology

Each monthly value is a simple average of the NSO "Average" concentration across the 17 Ulaanbaatar stations in the NSO tables that have data that month. Stations without data are left out, and no values are estimated or interpolated. SO₂ starts in February 2002, PM10 in December 2008 and PM2.5 in July 2010. Months with no reporting station (PM10 in April 2009, PM2.5 in August 2010) are blank.

The stations did not all operate for the whole period, so the mix changes over time. Before 2015, 2–8 stations have SO₂ data each month and at most 2 have PM2.5; from 2015, between 4 and 15 report. No month has all 17, so part of any change over time can come from which stations were reporting.

Four stations NSO added in 2026 (Yarmag, Nalaikh, Sharkhad and 5 Buudal) are not included, to keep the station set fixed. PM2.5 for September 2026 is left out because NSO's published values repeat PM10. For trend analysis, use the station-level NSO tables (for example "SULPHUR DIOXIDE, by location, by month"), which also give each station's number of measurements.