It is learned from the Institute of Tibetan Plateau Research of the Chinese Academy of Sciences that the research team of the researcher Cong Zhiyuan and collaborators of the institute found that the reduction of Arctic sea ice will increase the transport of pollutants such as aerosols to the Tibetan Plateau. At present, the warming rate of the Qinghai-Tibet Plateau is more than twice that of the past 30 years. From the perspective of global linkage, reducing man-made emissions is the only way to control environmental risks in the region. This result was recently published online in the academic journal “Nature-Climate Change”.
Cong Zhiyuan’s research team analyzed the long-term observational data of atmospheric aerosols in Nam Co and Mount Everest, and found that most of the aerosol optical thickness (AOD) showed a significant annual peak in April each year. And this time period is the period of high incidence of pollution incidents such as forest fires and crop residue burning in South Asia.
The first author of the article, Dr. Li Fei from the University of Bergen, said that under the background of global warming, the melting of Arctic sea ice has accelerated. Through statistical diagnostic analysis, it was found that the Arctic sea ice on the North Atlantic side decreased in February, which caused abnormal warming of the ocean surface and the bottom of the atmosphere in the area, and reduced atmospheric temperature gradients in the Arctic and mid-latitudes. According to the principle of thermal wind, the polar jets in the area weakened, and the warm and humid ocean air flow to the inland of high latitude Eurasian continent decreased, which led to the decrease of the snow depth near the Ural Mountains from February to April, which in turn affected the large-scale disturbance of the westerly zone in April , The East Asian subtropical westerly jet strengthened. Affected by the topography of the Qinghai-Tibet Plateau, the enhanced updraft combined with the mesoscale circulation system such as the valley wind on the Qinghai-Tibet Plateau accelerates South Asian pollutants to cross the Himalayas and enter the Qinghai-Tibet Plateau.
”Under the background of global warming, the melting of Arctic sea ice in winter has intensified, affecting atmospheric circulation, weakening atmospheric diffusion conditions, increasing the accumulation of aerosols on the Qinghai-Tibet Plateau, and accelerating the melting of glaciers on the Qinghai-Tibet Plateau. At present, the Qinghai-Tibet Plateau remains clean as a whole. External disturbances continue to increase, which will exacerbate a series of environmental risks.” said the co-corresponding author of the article, Dr. Wan Xin from Institute of Qinghai-Tibet Plateau, Chinese Academy of Sciences.
