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2. It’s been encouraging to see use of data in the NSO publication on the health effects of air pollution, but the series starts only in January 2014. You can see a higher level of PM10 at that point.
1212.mn/BookLibraryDow…
1212.mn/BookLibraryDow…
3. To understand what has happened, you have to go farther back. Here is the monthly average of PM2.5 from summer 2010 through 12/2017, as published in NSO’s statistical yearbook. 1212.mn @statistic_mn #утаа
4. PM10 is not as good a measure, but it is correlated with PM2.5 and stretches back farther, so it is also useful to analyze. PM10 was increasing until around 2011, then decreasing until 2014 or so. (Levels still WAY too high, obviously.)
5. These findings are consistent with the annual averages for PM2.5 and PM10 for the city published on tsag-agaar.mn
6. NSO and other sites also publish monthly data by station. The data series that stretch that far back confirm that there was a decline in peak levels after 2011. (Other stations were added in more recent years.)
7. This decline happened even though the city was, and still is, growing rapidly. Here is Ulaanbaatar’s population and number of registered vehicles.
8. (Charts made from NSO’s helpful site 1212.mn @statistic_mn . Detailed data on households in ger areas or by heating type are collected during the census years, but for now population and vehicles suffice to show the cities growth.)
9. If population was steadily growing, why did the peak levels of air pollution not continue to grow, but even declined from 2011 to 2015? Those years coincided with the program to distribute less-polluting stoves, supported by MCC, the World Bank, and others ...
10. … The stove program was stopped by the government in 2015. Cleaner stoves supplied by various partners :
2011 65,502
2012 37,354
2013 41,044
2014 20,916
2015 10,802
2011 65,502
2012 37,354
2013 41,044
2014 20,916
2015 10,802
11. Many early stoves were imports, but others were made by Mongolian artisans, designed for local consumers. A testing station certifies stoves that pass a test (some 22 models have been approved). A stove development center helps artisans build better stoves.
12. In the absence of regulation, some people sold their low-emitting stoves, since they are of high quality and can fetch a good price, and reverted to cheaper traditional stoves. (I have seen the subsidized stoves in the Gobi and in Ovorhangai.) …
13. … In addition, stoves wear out and need replacement parts. In the absence of subsidies or regulatory incentives, the number of low-emitting stoves in Ulaanbaatar has dwindled.
14. It bears repeating that the declines from 2011 to 2015 were from very bad peak levels to lower-but-still-horrible levels. When there is no wind and there is a cold air inversion, it is as if the city has a ceiling. …
15. … Even with fewer traditional stoves, the pollution will still be there but smoke will take longer to accumulate. When traditional stoves are larger in number, it gets worse faster.
16. In the years since 2015, pollution levels have stagnated or gotten worse. The best data that is publicly available, provided by the US Embassy, gives hourly concentrations starting in October 2015. …
17. … The US embassy data mirrors the patterns of the earlier charts for the past four winters but extends them to the end of just a few hours ago. My chart based on stateair.mn/history.php
18. The Mongolian government now focuses on fuels and electrical heating, and the World Bank is supporting the design of a pilot to inform the govt’s larger plan on electric heating. At the same time, we believe low-emitting stoves should still be part of the plan.
19. Here is a video that colleagues made on Ulaanbaatar’s air pollution problem and approaches to reducing it. worldbank.org/en/news/featur…
20. There are many other contributors to the air pollution problem (low pressure boilers, vehicles, etc.), but I have focused on stoves as they are the main contributors to Ulaanbaatar’s smoke.
21. Why not have a more evidence-based discourse about air pollution? There are plenty of public resources available: 1212.mn , tsag-agaar.mn , stateair.mn/history.php #утаа
22/22 End.
*city’s growth
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