The changing pattern of lake and its contribution to increased mass in the Tibetan Plateau derived from GRACE and ICESat data
The changing pattern of lake and its contribution to increased mass in the Tibetan Plateau derived from GRACE and ICESat data
复制标题
根据 GRACE 和 ICESat 数据得出的青藏高原湖泊变化模式及其对质量增加的贡献
DOI：
10.1093/gji/ggw293
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发表时间：
2016
影响因子：
2.8
通讯作者：
Sun Wenke
中科院分区：
文献类型：
--
作者：
Wang Qiuyu;Yi Shuang;Sun Wenke
通过对比GRACE（重力恢复与气候实验）和ICESat（冰、云、陆面高程卫星）观测资料，验证青藏高原观测到的重力增加是否主要由湖泊蓄水量增加引起，并综合分析了2003-2009年青藏高原湖泊水位的变化规律。采用改进的自动化方法获取湖泊水位变化，并考虑了湖泊面积扩大和湖泊密度对湖泊蓄水量的低估。结果表明，GRACE卫星记录的总TP/内TP质量增加（16.43 ± 1.65/11.79 ± 1.25 gt a−1），其中湖泊储量增加占ICESat的（8.78 ± 0.75/7.53 ± 0.56 gt a−1）。西北部的残留物可能储存在新的湖泊和土壤水分作为净降水量增加的结果。根据湖平面变化特征，将TP划分为四个亚区。湖泊水位的变化与降水的分布基本一致，即TP内湖水位增加，而印度河和雅鲁藏布江上游湖水位减少。在东北TP在2005年和2009年夏季的降雨量过多造成了同时在许多湖泊的水位大幅增加。湖泊变化与降水的相关性表明，在大多数地方，降水而不是冰川融化是湖泊水位变化的主要原因。尽管如此，融水对Selin Co和Nam Co等冰川附近的湖泊来说是一个相当大的补充，这部分解释了为什么GRACE表明该地区的信号要弱得多。
This paper compares GRACE (Gravity Recovery and Climate Experiment) and ICESat (Ice, Cloud and land Elevation Satellite) observations to confirm whether the observed gravity increase in the Tibetan Plateau (TP) was primarily caused by lake storage gain, and comprehensively analyses the changing pattern of lake level over 2003–2009. An improved automated method was used to obtain lake-level changes and the underestimation of lake water storage was considered due to lake area expansion and lake density. The result demonstrates that GRACE recorded a mass gain (16.43 ± 1.65/11.79 ± 1.25 gt a−1) in the total/inner TP, of which lake storage increase accounts for (8.78 ± 0.75/7.53 ± 0.56 gt a−1) based on ICESat. The northwestern residual may be stored in new lakes and soil moisture as a result of net precipitation gain. According to the character of the lake-level changes, we divide the TP into four subregions. Generally, the changing pattern of lake level concurs with the distribution of precipitation, which is increasing in the inner TP and decreasing in the upstream area of the Indus and Brahmaputra Rivers. An excess of rainfall in the northeastern TP in the summer of 2005 and 2009 caused a simultaneous large increase in water level in many lakes. The correlation of lake changes with precipitation demonstrates that precipitation rather than glacial melt is the main cause of lake-level change in most places. Nonetheless, the meltwater is a considerable supplement for lakes near glaciers such as Selin Co and Nam Co, which partly explains why GRACE indicates a much weaker signal in this region.