title: Sources of black carbon to the Himalayan-Tibetan Plateau glaciers.
abstract: Combustion-derived black carbon (BC) aerosols accelerate glacier melting in the Himalayas and in Tibet (the Third Pole (TP)), thereby limiting the sustainable freshwater supplies for billions of people. However, the sources of BC reaching the TP remain uncertain, hindering both process understanding and efficient mitigation. Here we present the source-diagnostic Δ(14)C/δ(13)C compositions of BC isolated from aerosol and snowpit samples in the TP. For the Himalayas, we found equal contributions from fossil fuel (46±11%) and biomass (54±11%) combustion, consistent with BC source fingerprints from the Indo-Gangetic Plain, whereas BC in the remote northern TP predominantly derives from fossil fuel combustion (66±16%), consistent with Chinese sources. The fossil fuel contributions to BC in the snowpits of the inner TP are lower (30±10%), implying contributions from internal Tibetan sources (for example, yak dung combustion). Constraints on BC sources facilitate improved modelling of climatic patterns, hydrological effects and provide guidance for effective mitigation actions.
authors.affiliation: Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences (CAS), Beijing 100101, China.|CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing 100101, China.
authors.forename: Chaoliu
authors.initials: C
authors.lastname: Li
authors.affiliation: Department of Environmental Science and Analytical Chemistry; The Bolin Centre for Climate Research, Stockholm University, Stockholm 10691, Sweden.
authors.forename: Carme
authors.initials: C
authors.lastname: Bosch
authors.affiliation: CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing 100101, China.|State Key Laboratory of Cryosphere Science, Cold and Arid Regions Environmental and Engineering Research Institute, CAS, Lanzhou 730000, China.
authors.forename: Shichang
authors.initials: S
authors.lastname: Kang
authors.affiliation: Department of Environmental Science and Analytical Chemistry; The Bolin Centre for Climate Research, Stockholm University, Stockholm 10691, Sweden.
authors.forename: August
authors.initials: A
authors.lastname: Andersson
authors.affiliation: Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences (CAS), Beijing 100101, China.|University of CAS, Beijing 100049, China.
authors.forename: Pengfei
authors.initials: P
authors.lastname: Chen
authors.affiliation: Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences (CAS), Beijing 100101, China.|CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing 100101, China.
authors.forename: Qianggong
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences (CAS), Beijing 100101, China.|CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing 100101, China.
authors.forename: Zhiyuan
authors.identifier: 0000-0002-7545-5611
authors.initials: Z
authors.lastname: Cong
authors.affiliation: Environmental Research Institute, School of Environmental Science and Engineering, Shandong University, Jinan 250100, China.
authors.forename: Bing
authors.initials: B
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Cryosphere Science, Cold and Arid Regions Environmental and Engineering Research Institute, CAS, Lanzhou 730000, China.
authors.forename: Dahe
authors.initials: D
authors.lastname: Qin
authors.affiliation: Department of Environmental Science and Analytical Chemistry; The Bolin Centre for Climate Research, Stockholm University, Stockholm 10691, Sweden.
authors.forename: Örjan
authors.initials: Ö
authors.lastname: Gustafsson