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Quantitative analysis of Arctic ice flow acceleration with increasing temperature

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Acta Oceanologica Sinica 2021年第1期40卷 22-32页

作者： Zemin Wang Boya Yan Songtao Ai Kim Holmén Jiachun An Hongmei Ma Chinese Antarctic Center of Surveying and Mapping Wuhan UniversityWuhan 430079China Norwegian Polar Institute Longyearbyen 9170Norway Polar Research Institute of China Shanghai 200136China

This study explores the ice flow acceleration(21.1%)of Pedersenbreen during 2016–2017 after the extremely warm winter throughout the whole Arctic in 2015/2016 using in situ data and quantitatively analyses the factors contributing to this *** data sets,including 2008–2018 air temperature data from Ny-?lesund,ten-year in situ GPS measurements and Elmer/Ice ice flow modelling under different ice temperature scenarios,suggest that the following factors contributed to the ice flow acceleration:the softened glacier ice caused by an increase in the air temperature(1.5℃)contributed 2.7%–30.5%,while basal lubrication contributed 69.5%–97.3%.The enhanced basal sliding was mostly due to the increased surface meltwater penetrating to the bedrock under the rising air temperature conditions;consequently,the glacier ice flow acceleration was caused mainly by an increase in subglacial *** Pedersenbreen,there was an approximately one-year time lag between the change in air temperature and the change in glacier ice flow velocity.

关键词： ice flow velocity Arctic temperature rising Pedersenbreen Elmer/Ice meltwater

Regimes of Runoff Components on the Debris-covered Koxkar Glacier in Western China

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Journal of Mountain Science 2015年第2期12卷 313-329页

作者： HAN Hai-dong DING Yong-jian LIU Shi-yin WANG Jian State Key Laboratory of Cryospheric Sciences Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences

By using a degree-day based distributed hydrological model, regimes of glacial runoff from the Koxkar glacier during 2007-2011 are simulated, and variations and characteristics of major hydrological components are discussed. The results show that the meltwater runoff contributes 67.4%, of the proglacial discharge, out of which snowmelt, clean ice melting, buried-ice ablation and ice-cliff backwasting account for 22.4%, 21.9%, 17.9% and 5.3% of the total melt runoff, respectively. Rainfall runoff is significant in mid-latitude glacierized mountain areas like Tianshan and Karakorum. In the Koxkar glacier catchment, about 11.5% of stream water is initiated from liquid precipitation. Spatial distributions for each glacial runoff component reveal the importance of climatic gradients, local topography and morphology on glacial runoff generation, and temporal variations of these components is closely related to the annual cycle of catchment meteorology and glacier storage. Four stages are recognized in the seasonal variations of glacier storage, reflecting changes in meltwater yields, meteorological conditions and drainage systems in the annual hydrological cycle.

关键词： Debris cover meltwater Glacier Koxkar Runoff

The transport of chemical components in homogeneous snowpacks on Urumqi Glacier No.1, eastern Tianshan Mountains, Central Asia

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Journal of Arid Land 2015年第5期7卷 612-622页

作者： YOU Xiaoni LI Zhongqin Ross EDWARDS WANG Lixia Key Laboratory of Cryosphere and Environment/Tianshan Glaciological Station/Laboratory of Ice Core and Cold Regions Environment Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Tianshui Normal University Imaging and Applied Physics Curtin University of Technology

Chemical records from alpine ice cores provide an invaluable source of paleoclimatic and environ- mental information. Not only the atmospheric chemical composition but also depositional and post-depositional processes are recorded within snow/tim strata. To interpret the environmental and climatic significance of ice core records, we studied the variability of glacier snowpack chemistry by investigating homogeneous snowpacks from October 2003 to September 2006 on Urumqi Glacier No. 1 in eastern Tianshan Mountains, Central Asia. Principle Component Analysis of ionic species in dry and wet seasons revealed the impact of meltwater in redistributing ions in the snowpacks. The 1st, 2nd and 3rd principle components for dry seasons differ significantly, reflecting complex associations between depositional or/and post-depositional processes. The variability trend of ionic concentrations during the wet seasons was found to fit a Gauss Function with significant parameters. The elution factor revealed that more than half of ions are leached out during the wet seasons. Differences with respect to ion snowpack mo- bility were found. Of the ions studied SO42- was the most mobile and Mg2＋ the least mobile. A threshold relationship between air temperatures and the elution process was investigated over the study period. The results indicate that the strong melt/ablation processes and iconic redistribution occur at a threshold air temperature of 0℃. The study found that surface melt on the snowpacks is the main factor causing the alteration of the snowpack chemistry. Rainfall also has an impact on the chemistry but plays a less significant role than the surface melt.

关键词： Urumqi Glacier No. 1 snowpack meltwater air temperature precipitation

Lake-expanding events in the Tibetan Plateau since 40 kaBP

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Science China Earth Sciences 2001年第S1期44卷 301-315页

作者：贾玉连施雅风王苏民蒋雪中李世杰王爱军李徐生

Since 40 kaBP, the current endorheism on the Tibetan Plateau had experienced at least four lake-expanding events, at 40-28 kaBP, 19-15 kaBP, 13-11 kaBP, 9.0-5.0 kaBP, respectively. The 40-28 kaBP and 9.0-5.0 kaBP lake-expanding events, corresponding to the global warming periods, were mainly determined by the abundant summer monsoon rainfall brought by strong Indian monsoon, aroused by enhanced solar radiation at earth orbital precessional cycle. The 40-28 kaBP lake-expanding event, also called the great lake period or the pan-lake period, for several great lake groups had come into being by the interconnection of the presently isolated and closed lake catchments. The total lake area over the Tibetan Plateau was estimated at least up to 150000 km2, 3.8 times of the present, and the lake supply coefficients were about 3-10. The 9.0-5.0 kaBP lake-expanding, with a total lake area of 68000 km2, less than the above mentioned reflected the Indian monsoon rainfall less than that of 40-28 kaBP. The expanded lakes at 19-15 kaBP and 13-11 kaBP, distributed in these basins with more or less existing glacial, indicated plenty of glacial meltwater discharged to balance evaporation on expansive lake surface. At the same time, the enhanced precipitation by the westerlies at 19-15 kaBP and by Indian monsoon at 13-11 kaBP plays an important role in maintaining the high lake level. Heinrich events greatly affected the evolution of climate system over the Tibetan Plateau, and thus gave a clear boundary of the high lake level change in the late Quaternary.

关键词： the Tibetan Plateau lake-expanding event monsoon rainfall glacial meltwater precessional cycle Heinrich event.

ANALYSIS OF TRITIUM CONTENT IN GLACIER WATER IN HENGDUAN MOUNTAINS

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Chinese Science Bulletin 1988年第13期33卷 1117-1120页

作者：王立伦王平 Lanzhou Institute of Glaciology and Gcocryology Academia Sinica

Glacier is a movable natural icebody formed from the concentration and evolu- tion of solid precipitation. Tritium is an ideal tracer for the conversion process of glacier water. The measurement of tritium content in ... 详细信息

关键词： glacier water tritium content Hengduen Mts snowfall meltwater