Why the air in Tashkent and other Uzbek cities gets dirty in autumn and winter
Every autumn and winter, the air in Tashkent and many other cities of Uzbekistan gets noticeably dirtier. It is usually worst in the evening, at night and early in the morning. On calm days the US AQI in Tashkent can stay around 150–250 for many hours, which is in the "unhealthy" or "very unhealthy" range. The cause is the weather combined with sources of smoke and dust.
The key factor is a temperature inversion. Normally the air near the ground is warmer, so it rises and carries pollution upward. In the cold season, a layer of warmer air often sits on top of colder air near the ground and acts like a lid. When the wind is weak and there is no rain or snow, smoke and dust stay low over the city. Uzhydromet explains pollution levels by how well the weather spreads pollution out. Wind and rain or snow clear the air. A cold anticyclone brings clear, calm and frosty weather and can make the inversion stronger.
The sources of pollution are coal-burning greenhouses and boilers during the heating season, vehicle exhaust, and dust from construction sites and roads. Trucks carrying uncovered loads also raise dust. In the west of the country, especially in Nukus and Urgench, the Uzhydromet bulletin often records dust above the daily limit. Dust storms from dry areas can add to this.
What officials are doing: the Ecology Committee carries out regular inspections. In one week in November 2025 it checked 1,449 greenhouses, stopped work at 67 and fined 403 people. In Tashkent it inspected 235 construction sites and suspended work at 34. It also found 837 trucks with uncovered loads and fined 206 drivers for emissions above the limits. Cabinet of Ministers Resolution No. 586 says greenhouses that burn solid fuel must switch to other heating by 1 December 2026. The state pays up to 50% of the cost.
How to read the numbers: apps show the US EPA AQI, where 0–50 is good, 51–100 moderate, 101–150 unhealthy for sensitive groups, 151–200 unhealthy and 201–300 very unhealthy. The AII in the Uzhydromet bulletin is a different, Uzbek index. It is calculated from several pollutants measured at its stations. On the AII scale, below 5 is low, 5–7 elevated, 7–14 high, and 14 or more very high. This means you cannot compare the two numbers directly: on the same day the AII can be low while the AQI is high.
Who should be careful and what to do
Children, older people, pregnant women and people with asthma, heart disease or lung disease are the most sensitive to polluted air.
- Check the AQI before you go out. If it is above 150, wear an N95/FFP2 mask outdoors. Simple cloth masks help very little.
- Move running and other exercise indoors. Walk away from busy roads.
- Keep windows shut in the evening, at night and early in the morning. Air out your rooms during the day, when the air is usually cleaner. An air purifier with a HEPA filter also helps.
- Tourists should plan outdoor sightseeing for the daytime and leave museums and other indoor sights for the evening.
- The air usually clears after wind, rain or snow, so keep an eye on the forecast.
If you have chest pain or trouble breathing, see a doctor.
Sources
- Uzhydromet: Ecological Bulletin
- Ecology Committee: inspections 24–28 November 2025
- Ecology Committee: raid 23–24 October 2026, greenhouse heating
- MET Norway Locationforecast (CC BY 4.0)
uzbekai.com wrote this article with the help of AI, from our own readings, the forecast and official sources. If you see a mistake, tell us through the Help page.