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JOURNAL OF GEOPHYSICAL RESEARCH,
VOL. 108, NO. D23,
8653,
doi:10.1029/2002JD003178,
2003
A high-resolution numerical study of the Asian dust storms of April 2001
Ming Liu
Naval Research Laboratory, Monterey, California, USA
Douglas L. Westphal
Naval Research Laboratory, Monterey, California, USA
Shigong Wang
Department of Atmospheric Science, Lanzhou University, Lanzhou, China
Atsushi Shimizu
National Institute for Environmental Studies, Tsukuba, Japan
Nobuo Sugimoto
National Institute for Environmental Studies, Tsukuba, Japan
Jun Zhou
China Academy of Sciences, Anhui Institute of Optics and Fine Mechanics, Anhui, China
Yan Chen
China-Japan Friendship Center for Environmental Protection, Beijing, China
Abstract
A comprehensive dust aerosol model is developed and fully coupled to the U. S. Navy's operational Coupled Ocean/Atmospheric
Mesoscale Prediction System (COAMPS™). The model is used to simulate the Asian dust storms of 5–15 April 2001 at 27-km resolution
with 46 vertical layers. Dust was primarily generated in the Gobi and Taklamakan Deserts between 6 and 9 April and then swept
across vast areas of east Asia. The model performance is verified with satellite products and by observations of PM10 and
lidar data from Lanzhou, Beijing, Hefei, Tsukuba, and Nagasaki. The model simulates the right timing and strength of dust
events, predicting depths and magnitudes of the boundary layer and elevated layer of dust plumes that compare well with observed
values. Numerical analysis shows that the first Mongolia cyclone on the 6 and 7 April and the cold front on 8 and 9 April,
accompanied by a second Mongolia low, form the major dynamic forcing patterns that mobilize, transport, and vertically redistribute
the dust. Both cyclones entrain the dust and transport dust to altitudes of 8–9 km, while at the top of the cyclone, transport
is anticyclonic and to the northeast. The analysis of the individual dynamic and microphysical tendency terms in the mass
continuity equation reveals that in the dust generation area, mechanical and convective turbulence plays the major role in
mixing dust upward to the top of the planetary boundary layer. In the downstream cyclone area, vertical advection by the model-resolved
upward motion in the cyclones is the dominant dynamic process that transports dust to high altitudes and into the westerlies,
making it available for long-range transport. The mass budget calculation for the entire simulation period reveals that about
75% of the total dust production is redeposited to the Asian deserts, 20% falls onto nondesert areas through dry and wet deposition,
and 1.6% falls into the China and Japan Seas.
Received 15
November
2002;
accepted 26
March
2003;
published 14
August
2003.
Index Terms: 0305 Atmospheric Composition and Structure: Aerosols and particles (0345, 4801); 0322 Atmospheric Composition and Structure: Constituent sources and sinks; 0341 Atmospheric Composition and Structure: Middle atmosphere—constituent transport and chemistry (3334).
Read Full Article (file size: 6187701 bytes) Cited by
Citation: Liu, M., D. L. Westphal, S. Wang, A. Shimizu, N. Sugimoto, J. Zhou, and Y. Chen
(2003),
A high-resolution numerical study of the Asian dust storms of April 2001,
J. Geophys. Res.,
108(D23),
8653,
doi:10.1029/2002JD003178.
Copyright 2003 by the American Geophysical Union.
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