Pedersenbreen is a small polythermal valley glacier, located in Svalbard, which has been one of the two glaciers monitored by Chinese Arctic expedition members since 2004. This study estimates its area and volume and ...Pedersenbreen is a small polythermal valley glacier, located in Svalbard, which has been one of the two glaciers monitored by Chinese Arctic expedition members since 2004. This study estimates its area and volume and analyzes its change during 1936-1990-2009, using field collected GPS/GPR data in 2009 and historical topographic maps published by the Norwegian Polar Institute. We have found that Pedersenbreen is just like many other valley glaciers in Svalbard, having experienced a significant recession since the end of Little Ice Age in the early 20th century. The glacier tongue has retreated more than 0.6 km, while ice volume has decreased by approximately 13%. The overall thinning rate of Pedersenbreen has shown acceleration during the recent decades. Further analysis shows that the ice tongue in the downstream area of Pedersenbreen is melting at the highest rate, while a simultaneous accumulation occurred in the upstream. However, as global temperatures increase, the accumulation area is reducing year by year.展开更多
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 factor...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 acceleration.Several 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 water.For Pedersenbreen,there was an approximately one-year time lag between the change in air temperature and the change in glacier ice flow velocity.展开更多
基金supported by the National High Technology Research and Development Program of China (2012AA12A304)the National Natural Science Foundation of China (41076126, 41106163, 41174029 and 41176172)+1 种基金the Chinese Polar Scientific Strategy Project (20080203 and 20100103)the Chinese Polar Environment Comprehensive Investigation & Assessment Programmes (CHINARE2013-04-07 and CHINARE2013-02-04)
文摘Pedersenbreen is a small polythermal valley glacier, located in Svalbard, which has been one of the two glaciers monitored by Chinese Arctic expedition members since 2004. This study estimates its area and volume and analyzes its change during 1936-1990-2009, using field collected GPS/GPR data in 2009 and historical topographic maps published by the Norwegian Polar Institute. We have found that Pedersenbreen is just like many other valley glaciers in Svalbard, having experienced a significant recession since the end of Little Ice Age in the early 20th century. The glacier tongue has retreated more than 0.6 km, while ice volume has decreased by approximately 13%. The overall thinning rate of Pedersenbreen has shown acceleration during the recent decades. Further analysis shows that the ice tongue in the downstream area of Pedersenbreen is melting at the highest rate, while a simultaneous accumulation occurred in the upstream. However, as global temperatures increase, the accumulation area is reducing year by year.
基金The National Key R&D Program of China under contract No.2016YFC1402701the National Natural Science Foundation of China under contract Nos 41941010,41531069 and 41476162
文摘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 acceleration.Several 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 water.For Pedersenbreen,there was an approximately one-year time lag between the change in air temperature and the change in glacier ice flow velocity.
