Source and evolution of the “perfect Asian dust storm” in early April 2001: Implications of the Sr–Nd isotope ratios
Source and evolution of the “perfect Asian dust storm” in early April 2001: Implications of the Sr–Nd isotope ratios
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DOI：
10.1016/j.atmosenv.2005.05.050
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发表时间：
2005-09
影响因子：
5
通讯作者：
T. Nakano;M. Nishikawa;I. Mori;K. Shin;T. Hosono;Y. Yokoo
中科院分区：
文献类型：
--
作者：
T. Nakano;M. Nishikawa;I. Mori;K. Shin;T. Hosono;Y. Yokoo
2001年4月初，这场“完美亚洲沙尘暴”发生在中国北部和蒙古的大片地区，并向东横跨北太平洋。这是地球轨道卫星拍摄到的一张巨大而清晰的图像。我们测定了这次风暴尘埃中耐酸矿物的锶-钕同位素比值和弱酸溶矿物的锶同位素比值，并与中国北部地表干旱土壤的比值进行了比较。粉尘矿物的同位素组成与巴丹朱兰沙漠、腾格里沙漠、乌兰布和沙漠及其以北地区的土壤相似，因气象原因被认为是尘埃羽流的排放区，但它们的区域差异较大，反映了源地土壤的异质性。我们的结果以及其他气象和模拟研究的结果表明，这种变化是由于当地土壤被抬升到沙尘羽流的下部，但在更远的下风方向，沙尘与当地土壤的混合较少，主要来自上部沙尘羽流。关于亚洲沙尘和中国北部和蒙古土壤的矿物同位素、矿物学和元素数据为沙尘暴的物理和化学过程以及沙尘源地区提供了宝贵的信息。
The “perfect Asian dust storm,” so-called from the huge, clear picture obtained of it by earth-orbiting satellites, occurred over a vast area of northern China and Mongolia and moved eastward across the northern Pacific in early April 2001. We determined the Sr–Nd isotopic ratios of acid-resistant minerals and the Sr isotopic ratios of weak-acid-soluble minerals in the dust from this storm deposited at nine sites from northern China to Japan and compared these data with those ratios of surface arid soils in northern China. The isotopic compositions of the dust minerals resembled those from soils of the Badain Juran, Tengger, and Ulan Buh deserts and the area to their north, which on meteorological grounds are considered to be the emission area of the dust plume, but they varied regionally, reflecting the heterogeneity of the source soils. Our results and those of other meteorological and modeling studies suggest that this variation was caused by mixing with local soils uplifted into the lower part of the dust plume, but further downwind the dust was less mixed with local soils and was derived mainly from the upper dust plume. Mineral isotope, mineralogical, and elemental data on Asian dusts and soils in northern China and Mongolia provide invaluable information on physical and chemical processes of dust storms and on dust source areas.