Spatial Distribution of Asian Dust Captured by Lidars in the Gobi Desert in May 2013
Abstract
Asian dust originates in arid and semi-arid regions of East Asia such as the Gobi Desert and the Taklimakan Desert. The dust is lifted up by strong wind from the ground to the atmospheric boundary layer (ABL). If the dust reaches the free troposphere (FT), it can be transported to the North Pacific region over a long range by the westerlies. Therefore, the spatial distribution of the dust is a key factor of the long-range transport. Three lidars are monitoring the vertical distribution of the dust in the Gobi Desert. They are located in Dalanzadgad (DZ), Sainshand (SS), and Zamyn-Uud (ZU). We aim to reveal a mechanism to transport the dust from ABL to FT by using the lidars with meteorological analyses. A dust event was generated by strong wind ( 16 m/s) in the Gobi Desert on 22-23 May 2013. The strong wind was due to a developing low pressure system with a cold front. The cold front passed DZ, SS, and ZU in this order. In the three sites, a dust layer extended from the ground to a height of about 2 km around the cold front. Some dust floated along the surface of the cold front over a cold air mass. The dust was located in the updraft region of the cold front system. The maximum height of the dust was 1.4 km in DZ. The dust reached about a height of 4 km in SS and ZU. In addition, the dust distribution was larger in SS and ZU than that in DZ. These results suggest that the dust was transported by the updraft along the surface of the cold front in the cold frontal system. Also, the dust was transported to a higher height by the updraft while the cold front moved through the Gobi Desert. In conclusion, the cold frontal system lifted up the dust from the ground to ABL by the strong wind and transported it from ABL to FT by the updraft.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2016
- Bibcode:
- 2016AGUFM.A21E0127K
- Keywords:
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- 0305 Aerosols and particles;
- ATMOSPHERIC COMPOSITION AND STRUCTUREDE: 0365 Troposphere: composition and chemistry;
- ATMOSPHERIC COMPOSITION AND STRUCTUREDE: 3311 Clouds and aerosols;
- ATMOSPHERIC PROCESSESDE: 1631 Land/atmosphere interactions;
- GLOBAL CHANGE