Modulation of snow reflectance and snowmelt from Central Asian glaciers by anthropogenic black carbon.
Schmale JInstitute for Advanced Sustainability Studies, D-14467 Potsdam, Germany.
Flanner MDepartment of Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, MI 48109-2143, USA.
Kang SState Key Laboratory of Cryospheric Sciences, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, 730000 Lanzhou, China.
Sprenger MInstitute for Atmospheric and Climate Science, Swiss Federal Institute of Technology, CH-8092 Zurich, Switzerland.
Zhang QChinese Academy of Science Center for Excellence in Tibetan Plateau Earth Sciences, 100101 Beijing, China.
Guo JKey Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, 100101 Beijing, China.
Li YKey Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, 100101 Beijing, China.
Schwikowski MPaul Scherrer Institute, CH-5232 Villigen, Switzerland.
Farinotti DSwiss Federal Institute for Forest, Snow and Landscape Research, WSL, CH-8903 Birmensdorf, Switzerland.
English
Deposited mineral dust and black carbon are known to reduce the albedo of snow and enhance melt. Here we estimate the contribution of anthropogenic black carbon (BC) to snowmelt in glacier accumulation zones of Central Asia based on in-situ measurements and modelling. Source apportionment suggests that more than 94% of the BC is emitted from mostly regional anthropogenic sources while the remaining contribution comes from natural biomass burning. Even though the annual deposition flux of mineral dust can be up to 20 times higher than that of BC, we find that anthropogenic BC causes the majority (60% on average) of snow darkening. This leads to summer snowmelt rate increases of up to 6.3% (7 cm a-1) on glaciers in three different mountain environments in Kyrgyzstan, based on albedo reduction and snowmelt models.