第八届青年地学论坛

The Taklamakan Desert (TD) is known to emit large amounts of dust into the atmosphere every year, which can cause the darkening of snow on surrounding high-mountains after deposition, and perturbs the local radiation balance and hydrological cycles. However, previous field measurements have not been able to capture the impact of severe dust storms and are poorly represented on regional scales. Here, we used MODIS data and the Snow, Ice, and Aerosol Radiative (SNICAR) model to firstly reveal the significant snow darkening caused by heavy dust storm depositions. The severe snow storms can cause widespread snow darkening on the transport path, over almost all snow-covered areas of Tien Shan and Kunlun Mountains. This further accelerates snow aging, as characterized by the growth of snow grain size. The TD dust plumes can also be transported eastward and deposit onto the Qilian Mountains, ~1000 km away from the Tarim Basin. Our quantitative retrieval results demonstrate that severe dust storms in short days can cause more profound dust content, snow albedo reduction, and radiative forcing than persistent but relatively slow dust deposition during several months of no-event periods. This highlights the need to pay more attention to the impact of extreme events on the Earth's climate. We also demonstrate that severe snow darkening occurs not only in spring but also in summer, which may have important implications for climate and hydrological systems.
 

dust,snow albedo,radiative forcing,remote rensing