МОНГОЛ ОРНЫ ГОВЬ, ХЭЭРИЙН НУТГИЙН ТООСНЫ АГУУЛАМЖ

Abstract

We analyzed dust mass concentrations of PM10 and PM2.5 from seven monitoring stations in the Gobi Desert and steppe regions of Mongolia during 2009-2014. Annual averaged PM10 (PM2.5) concentrations were high in winter due to air pollution, in spring owing to dust storms and lower in summer. Annual variations of PM10 (PM2.5) were not available for Altai, Arvaikheer and Underkhaan due to data discontinuance. However, annual averages of PM10 (PM2.5) were higher at Arvaikheer site in winter months and lower at Altai and Underkhaan in all seasons. Annual averaged PM10 were about 46-51 мкг м-3 around Dalanzadgad in Umnugobi Aimag and Erdene (Ulaan-Uul) site in Dornogobi Aimag. Moreover, annual averaged PM2.5 was about 34-37 мкг м-3 around Dalanzadgad. Diurnal variations of PM10 (PM2.5) concentrations at all sites had two maxima in the morning and evening and two minima in the afternoon and early morning. The two maxima in the diurnal variation were coincided well with time periods of coal burning in stoves of private houses. This is an evidence of anthropogenic impacts on air quality.
During dust storms, huge amounts of fine dust particles were raised in the air. Daily maximum wind speeds were 26-40 m/s in the Gobi Desert and steppe regions in 28-29 April 2011 and dust mass concentrations of PM10 reached 1053 μg m−3 at Dalanzadgad, 1450 μg m−3 at Zamyn-Uud, and 4992 μg m−3 at Erdene. Lidar at Zamyn-Uud showed that dust was lifted to 1.5 km high from the ground level.