Light-absorbing impurities on glaciers are important factors that influence glacial surface albedo and accelerate glacier melt. In this study, the quantity of light-absorbing impurities on Keqikaer Glacier in western ...Light-absorbing impurities on glaciers are important factors that influence glacial surface albedo and accelerate glacier melt. In this study, the quantity of light-absorbing impurities on Keqikaer Glacier in western Tien Shan, Central Asia, was measured. We found that the average concentrations of black carbon was 2,180 ng/g, with a range from 250 ng/g to more than 10,000 ng/g. The average concentrations of organic carbon and mineral dust were 1,738 ng/g and 194 μg/g, respectively. Based on simulations performed with the Snow Ice Aerosol Radiative model simulations, black carbon and dust are responsible for approximately 64% and 9%, respectively, of the albedo reduction, and are associated with instantaneous radiative forcing of 323.18 W/m2(ranging from 142.16 to 619.25 W/m2) and 24.05 W/m2(ranging from 0.15 to69.77 W/m2), respectively. For different scenarios, the albedo and radiative forcing effect of black carbon is considerably greater than that of dust. The estimated radiative forcing at Keqikaer Glacier is higher than most similar values estimated by previous studies on the Tibetan Plateau, perhaps as a result of black carbon enrichment by melt scavenging. Light-absorbing impurities deposited on Keqikaer Glacier appear to mainly originate from central Asia, Siberia, western China(including the Taklimakan Desert) and parts of South Asia in summer, and from the Middle East and Central Asia in winter.A footprint analysis indicates that a large fraction(>60%) of the black carbon contributions on Keqikaer Glacier comes from anthropogenic sources. These results provide a scientific basis for regional mitigation efforts to reduce black carbon.展开更多
Air pollutants can be transported to the pristine regions such as the Tibetan Plateau,by monsoon and stratospheric intrusion.The Tibetan Plateau region has limited local anthropogenic emissions,while this region is in...Air pollutants can be transported to the pristine regions such as the Tibetan Plateau,by monsoon and stratospheric intrusion.The Tibetan Plateau region has limited local anthropogenic emissions,while this region is influenced strongly by transport of heavy emissions mainly from South Asia.We conducted a comprehensive study on various air pollutants (PM_(2.5),total gaseous mercury,and surface ozone) at Nam Co Station in the inland Tibetan Plateau.Monthly mean PM_(2.5)concentration at Nam Co peaked in April before monsoon season,and decreased during the whole monsoon season (June–September).Monthly mean total gaseous mercury concentrations at Nam Co peaked in July and were in high levels during monsoon season.The Indian summer monsoon acted as a facilitator for transporting gaseous pollutants (total gaseous mercury) but a suppressor for particulate pollutants (PM_(2.5)) during the monsoon season.Different from both PM_(2.5)and total gaseous mercury variabilities,surface ozone concentrations at Nam Co are primarily attributed to stratospheric intrusion of ozone and peaked in May.The effects of the Indian summer monsoon and stratospheric intrusion on air pollutants in the inland Tibetan Plateau are complex and require further studies.展开更多
The Tibetan Plateau is often referred to as the “roof of the world” because most of its area lies more than 4000 m above sea-level. As a result of this high altitude, the Tibetan Plateau stores the largest volume of...The Tibetan Plateau is often referred to as the “roof of the world” because most of its area lies more than 4000 m above sea-level. As a result of this high altitude, the Tibetan Plateau stores the largest volume of glacier after the Arctic and Antarctic regions and is often called the Earth's third pole [1]. It has recently been estimated that the glacier reserves of the Tibetan Plateau contain more than eight trillion cubic meters of water, which could supply more than two billion people [2]. A number of large rivers originate from the Tibetan Plateau, including the Yangtze River, Yellow River, Brahmaputra and Ganges, leading to it being called the “water tower of Asia”. The extreme environment and abundant water resources of the Tibetan Plateau mean that it forms a unique habitat for wildlife, and the genes of a large number of rare high-altitude plant and animal species are preserved in this important region.展开更多
基金supported by the National Natural Science Foundation of China (41630754, 41671067, and 41501063)the Chinese Academy of Sciences (KJZD-EW-G03-04), the State Key Laboratory of Cryosphere Science (SKLCS-ZZ-2015)the Foundation for Excellent Youth Scholars of Northwest Institute of Eco-Environment and Resources, CAS
文摘Light-absorbing impurities on glaciers are important factors that influence glacial surface albedo and accelerate glacier melt. In this study, the quantity of light-absorbing impurities on Keqikaer Glacier in western Tien Shan, Central Asia, was measured. We found that the average concentrations of black carbon was 2,180 ng/g, with a range from 250 ng/g to more than 10,000 ng/g. The average concentrations of organic carbon and mineral dust were 1,738 ng/g and 194 μg/g, respectively. Based on simulations performed with the Snow Ice Aerosol Radiative model simulations, black carbon and dust are responsible for approximately 64% and 9%, respectively, of the albedo reduction, and are associated with instantaneous radiative forcing of 323.18 W/m2(ranging from 142.16 to 619.25 W/m2) and 24.05 W/m2(ranging from 0.15 to69.77 W/m2), respectively. For different scenarios, the albedo and radiative forcing effect of black carbon is considerably greater than that of dust. The estimated radiative forcing at Keqikaer Glacier is higher than most similar values estimated by previous studies on the Tibetan Plateau, perhaps as a result of black carbon enrichment by melt scavenging. Light-absorbing impurities deposited on Keqikaer Glacier appear to mainly originate from central Asia, Siberia, western China(including the Taklimakan Desert) and parts of South Asia in summer, and from the Middle East and Central Asia in winter.A footprint analysis indicates that a large fraction(>60%) of the black carbon contributions on Keqikaer Glacier comes from anthropogenic sources. These results provide a scientific basis for regional mitigation efforts to reduce black carbon.
基金This study was supported by the Strategic Priority Research Program(A)of the Chinese Academy of Sciences(XDA20040501)the National Natural Science Foundation of China(41907328)+3 种基金State Key Laboratory of Cryospheric Science(SKLCS-ZZ-2020)financial support from the Chinese Academy of Sciences"Light of West China"Programfinancial support from the Youth Innovation Promotion Association of CAS(2016070)the support provided by the Institute for Advanced Sustainability Studies(IASS),which is funded by the German Federal Ministry for Education and Research(BMBF)and the Brandenburg Ministry for Science,Research and Culture(MWFK)。
文摘Air pollutants can be transported to the pristine regions such as the Tibetan Plateau,by monsoon and stratospheric intrusion.The Tibetan Plateau region has limited local anthropogenic emissions,while this region is influenced strongly by transport of heavy emissions mainly from South Asia.We conducted a comprehensive study on various air pollutants (PM_(2.5),total gaseous mercury,and surface ozone) at Nam Co Station in the inland Tibetan Plateau.Monthly mean PM_(2.5)concentration at Nam Co peaked in April before monsoon season,and decreased during the whole monsoon season (June–September).Monthly mean total gaseous mercury concentrations at Nam Co peaked in July and were in high levels during monsoon season.The Indian summer monsoon acted as a facilitator for transporting gaseous pollutants (total gaseous mercury) but a suppressor for particulate pollutants (PM_(2.5)) during the monsoon season.Different from both PM_(2.5)and total gaseous mercury variabilities,surface ozone concentrations at Nam Co are primarily attributed to stratospheric intrusion of ozone and peaked in May.The effects of the Indian summer monsoon and stratospheric intrusion on air pollutants in the inland Tibetan Plateau are complex and require further studies.
基金This study was supported by the Strategic Priority Research Program of the Chinese Academy of Sciences,the Pan-Third Pole Environment Study for a Green Silk Road(Pan-TPE)(XDA2004050202)the National Natural Science Foundation of China(41925032 and 41872100)the China Postdoctoral Science Foundation(2020M680696).
文摘The Tibetan Plateau is often referred to as the “roof of the world” because most of its area lies more than 4000 m above sea-level. As a result of this high altitude, the Tibetan Plateau stores the largest volume of glacier after the Arctic and Antarctic regions and is often called the Earth's third pole [1]. It has recently been estimated that the glacier reserves of the Tibetan Plateau contain more than eight trillion cubic meters of water, which could supply more than two billion people [2]. A number of large rivers originate from the Tibetan Plateau, including the Yangtze River, Yellow River, Brahmaputra and Ganges, leading to it being called the “water tower of Asia”. The extreme environment and abundant water resources of the Tibetan Plateau mean that it forms a unique habitat for wildlife, and the genes of a large number of rare high-altitude plant and animal species are preserved in this important region.