摘要
以野外实测数据为基础,分析北极Svalbard群岛Austre Lovénbreen和Pedersenbreen冰川表面运动特征。结果表明:(1)Austre Lovénbreen和Pedersenbreen冰川表面水平运动速度平均分别为2.14 m·a-1和6.28 m·a-1,变差系数平均分别为0.24和0.14,夏季水平运动速度略高于冬季,水平运动速度与其所处海拔高度具有多项式型关系,冰川主流线表面水平运动速度高于两侧,冰川两侧的表面水平运动速度不对称,Austre Lovénbreen冰川从源头至末端依次表现为运动的压缩区、拉伸区和压缩区;(2)Austre Lovénbreen和Pedersenbreen冰川表面垂直运动速度平均分别为0.76 m·a-1和0.90 m·a-1,两条冰川表面夏季垂直运动速度均大于冬季且夏季变差系数小,垂直运动速度与海拔高度具有一元线性相关性,表面物质平衡造成的高程变化对垂直运动速度的贡献率最大;(3)Austre Lovénbreen和Pedersenbreen冰川表面应变率分布表现为沿主流线方向逐渐减小然后负向增加,且其变差系数平均分别为0.19和0.15。
The glaciers Austre Lovenbreen and Pedersenbreen are located near Ny-Alesund on the Svalbard archipelago in the Arctic. Surface movement characteristics were analyzed using field data collected from 2005 to 2011 on both glaciers. The average horizontal velocities of Austre Lovenbreen and Pedersenbreen were 2.14 m· a^-1 and 6.28 m ·a^-1, respectively, and their corresponding variation coefficients were 0.24 and 0.14. The average horizontal velocity of the two glaciers in summer was slightly higher than that in winter. There was a muhinomial relationship between the glacial horizontal velocity and elevation. The horizontal velocity was larger along the mainstream line of the glaciers than that on the sides, and the distribution was not symmetrical between the two sides of Austre Lovenbreen. Based on the glacial movement features, Austre Lovenbreen could be divided into three regions from its origin to its terminus, a compressional region, a stretching region, and another compressional region. The average vertical velocities of Austre Lovenbreen and Pedersenbreen were 0.76 m · a^-1 and 0.90 m ·a^-1, respectively, and their corresponding variation coefficients were 0.81 and 0.59. The vertical velocities were higher in summer with a smaller variation coefficient than that in winter. There was a linear relationship between the glacial vertical velocity and elevation. Analysis of the contribution of different factors to vertical velocity showed that, on Austre Lovenbreen, height change caused by surface mass balance contributed most （64%）, followed by compensation flow （19%）, and horizontal velocity components （16%）. On Pedersenbreen, heigth change caused by surface mass balance again contributed most （40%）, followed by horizontal velocity components （35%）, and compensation flow （25 % ）. The surface strain rate decreased then increased negatively along the mainstream line on both Austre Lovenbreen and Pedersenbreen, and the corresponding average variation coefficients were 0.19 and 0.15, resp
出处
《极地研究》
CAS
CSCD
2015年第4期402-411,共10页
Chinese Journal of Polar Research
基金
国家自然科学基金(40876098)
国家社会科学基金(12BJY058)资助
