Reconstructing Greenland Ice Sheet meltwater discharge through the Watson River (1949–2017)
Reconstructing Greenland Ice Sheet meltwater discharge through the Watson River (1949–2017)
复制标题
重建格陵兰冰盖融水通过沃森河的排放（1949-2017）
DOI：
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发表时间：
2018
期刊：
影响因子：
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通讯作者：
M. R. van den Broeke
中科院分区：
文献类型：
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作者：
D. van As;B. Hasholt;A. Ahlstrøm;J. Box;J. Cappelen;W. Colgan;R. Fausto;S. Mernild;A. Mikkelsen;B. Noël;D. Petersen;M. R. van den Broeke
摘要冰盖融化是格陵兰西南部冰前沃森河的主要水源。自2006年以来，一直在监测通过沃森河排放的约12 000平方公里的大型冰盖集水区的排放量。虽然这个记录对于格陵兰岛的监测工作来说是相当长的，但对于解决气候信号来说太短了。因此，我们使用观察到的Tasersiaq湖流量和Kangerlussuaq气温重建年度沃森河流量回到1949年。由此产生的65年记录显示，自2003年以来，平均冰盖径流量相对于1949-2002年期间大约增加了46%。时间序列表明，自2003年以来，排放量最高的五个年份。三个排名靠前的排放年份（2010年，2012年和2016年）的特点是融化季节既长又激烈。自2003年以来，年际变化增加了一倍以上，我们推测这是因为增加了测高径流的放大作用，减少了积雪的渗透性。重建的时间序列被证明是一个有价值的工具，长期评估格陵兰冰盖表面质量平衡模型。与区域气候模型RACMO 2的缩小版本计算的淡水通量的比较显示出很高的相关性（r = 0.89），也表明，该模型可能低估径流高达26%以上的平均融化年。
ABSTRACT Ice-sheet melting is the primary water source for the proglacial Watson River in southern west Greenland. Discharge from the large, approximately 12,000 km2 ice-sheet catchment draining through the Watson River has been monitored since 2006. While this record is of respectable length for a Greenland monitoring effort, it is too short to resolve climate signals. Therefore, we use observed Tasersiaq lake discharge and Kangerlussuaq air temperature to reconstruct annual Watson River discharge back to 1949. The resulting sixty-five-year record shows that average ice-sheet runoff since 2003 has roughly increased by 46 percent relative to the 1949–2002 period. The time series suggests that the five top-ranking discharge years occurred since 2003. The three top-ranking discharge years (2010, 2012, and 2016) are characterized by melt seasons that were both long and intense. Interannual variability more than doubled since 2003, which we speculate to be because of hypsometric runoff amplification enhanced by albedo decrease and decreased firn permeability. The reconstructed time series proves to be a valuable tool for long-term evaluation of Greenland Ice Sheet surface mass balance models. A comparison with freshwater fluxes calculated by a downscaled version of the regional climate model RACMO2 reveals high correlation (r = 0.89), and also shows that the model possibly underestimates runoff by up to 26 percent in above-average melt years.
影响因子：
18.3
作者：
Chandler, D. M.;Wadham, J. L.;Hubbard, A.
通讯作者：
Hubbard, A.
影响因子：
18.3
作者：
Doyle, Samuel H.;Hubbard, Alun;Hubbard, Bryn
通讯作者：
Hubbard, Bryn