Particularities of Formation and Transport of Arid Aerosol in Central Asia

Abstract

The climate change is a global problem of humanity. During last decades anthropogenic air pollution is a main cause of the content change of the atmosphere. The situation constantly is redoubled by continuing intensive growth of the air pollution in the areas located near of emission sources and also far off territories. At the present the square of deserts increases in East Asia, and it affects on increasing of dusty days number. The total area of deserts and desertification lands is about 1.653 million km2 in Northern China [Wang T. & Zhu Z., 2001; Wang S., 2005]. More than 70% of the pastureland area of Mongolia is under desertification [Natsagdorj et al., 2003]. Gobi Desert covers 1/3 of Mongolia territories and is the driest area in the world. The climate of Gobi Desert is dry, cold, and more continental. Soils are poor with humus, containing a lot of gravel. Dust storm frequently occurs in arid and semi-arid territories of Central Asia. It is known that Gobi desert is one of the major sources of dust storms occurrence in the East Asia. Asian dust storms significantly influence on air quality [Chan et al., 2005; Gillette, 1986; Lee et al, 2006; Wei & Meng, 2006]. At the intense dust storms in Gobi desert the great many of sand and dust are transferred to Eastern China, Korea and Japan. Sometimes many particles of sand and dust are raised up by strong winds and transfer all over the world [Kim & Chung, 2008]. The total dust emission from sources in East Asia is estimated is 10.4×106 ton yr-1 for 『М10, 27.6×106 ton yr-1 for 『М30 and 51.3×106 ton yr-1 for 『М50. The total dust emission from Mongolian sources is 2×106 ton yr-1 for 『М10, 2.9×106 ton yr-1 for 『М30 and 8.7×106 ton yr-1 for 『М50. It is suggested that Southern Mongolia is an important dust source region [Xuan et al., 2004]. In recent years the intense dust storms are observed not only in Central Asia but also in different parts of the world. For example, strong dust storm was observed in Australia on 23 October 2002. The dust storm was 2400 km long, up to 400 km across and 1.5-2.5 km in height. The plume area was estimated at 840,860 km2 and was raised 3.35-4.85 million tones of sands and dust with ground [McTainsh et al., 2005].