Center for Atmospheric Chemistry Study, Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science and Engineering, Fudan University, Shanghai, 200433, China.
Department of Civil and Environmental Engineering, University of Tennessee, Knoxville, TN, 37996, USA.
Sci Rep. 2018 Apr 30;8(1):6779. doi: 10.1038/s41598-018-25166-5.
We firstly conducted a long-term in-situ field measurement at a marginal area (Hotan) of the southern Taklimakan Desert covering all four seasons. Detailed chemical characterization of dust aerosol over Hotan showed several unconventional features, including (1) ubiquity of high Na and Cl abundances in the Taklimakan dust aerosol and its Cl/Na ratio close to seawater; (2) high Ca content in the Taklimakan dust (7.4~8.0%) which was about two times of that in the natural crust; (3) high abundance of soluble sulfate concentrations and strong correlations between sulfate and Na and Cl as well as typical mineral tracers such as Al and Ca. Our results collectively indicated that the dust aerosol from the Taklimakan Desert was characterized of evident paelo-oceanic signature as the Taklimakan Desert was found as an ocean in the ancient times from the perspective of paleogeology. It was estimated that primary sources dominated the total abundances of sulfate during the dust seasons while previous climate modeling works had seldom considered the cooling effects of sulfate from the Taklimakan Desert.
我们首先在塔克拉玛干沙漠南部的一个边缘地区（和田）进行了为期四个季节的长期现场原位测量。和田粉尘气溶胶的详细化学特征显示了几个非传统特征，包括（1）塔克拉玛干粉尘气溶胶中普遍存在高浓度的 Na 和 Cl 以及接近海水的 Cl/Na 比值；（2）塔克拉玛干粉尘中的 Ca 含量较高（7.4%至 8.0%），约为天然地壳中的两倍；（3）可溶性硫酸盐浓度高，硫酸盐与 Na 和 Cl 之间存在强烈相关性，以及 Al 和 Ca 等典型的矿物示踪剂。我们的结果表明，塔克拉玛干沙漠的粉尘气溶胶具有明显的古海洋特征，从古地质学的角度来看，塔克拉玛干沙漠在古代是一片海洋。据估计，在粉尘季节，主要来源主导了硫酸盐的总含量，而之前的气候建模工作很少考虑来自塔克拉玛干沙漠的硫酸盐的冷却效应。
