Interannual Variability of Atmospheric Conditions and Surface Melt in Greenland in 2000–2014
Interannual Variability of Atmospheric Conditions and Surface Melt in Greenland in 2000–2014
复制标题
2000-2014年格陵兰岛大气条件和地表融化的年际变化
DOI：
--
复制
发表时间：
2018
期刊：
影响因子：
--
通讯作者：
M. Schäfer
中科院分区：
文献类型：
--
作者：
I. Välisuo;T. Vihma;R. Pirazzini;M. Schäfer
我们研究了2000年至2014年格陵兰岛表面融化的变化与夏季大气条件的关系。我们将熔化量化为熔化日数（NMD）、累积和最大熔化程度（基于微波辐射计数据），并建立了熔化量模型。最大融化范围的年际变化（以天为时间尺度）与NMD、累积融化范围和模拟融化量的年际变化不同，后者在整个融化季节累积。在格陵兰冰盖上平均，总柱水的年际变化与NMD（平方相关系数0.83）、累积融化程度（平方相关系数0.84）和模拟融化量（0.82）密切相关。NMD与格陵兰阻塞指数、NMD与北大西洋涛动指数、模拟融化量和NAOI之间存在显著的相关性，但相关性不强。NMD与沿海地区总柱水异常强度密切相关。个别夏季，南风正异常与NMD正异常相吻合。在东部沿海，正的NMD异常发生在更强的下坡风下，表明下沉加热主导了来自内部冰盖的冷空气平流。2012年夏季极端融冰和2013年夏季最小融冰的差异部分可以解释为2012年格陵兰东北部西南气团比2013年出现更多（更少）。在15年的时间里，峰顶的东北气团起源是与最大融化程度最强（负）相关的变量。
We addressed the variations of surface melt in Greenland in association with summertime atmospheric conditions from 2000 to 2014. We quantified melt as the number of melt days (NMD), cumulative and maximum melt extent (based on microwave radiometer data), and modeled melt amount. Interannual variations of the maximum melt extent, occurring in timescales of days, differed from those in NMD, cumulative melt extent, and modeled melt amount, which accumulate over the entire melt season. Averaged over the Greenland ice sheet, interannual variations in total column water strongly correlated with NMD (squared correlation coefficient 0.83), cumulative melt extent (0.84), and modeled melt amount (0.82). Significant but less strong correlations were detected between NMD and the Greenland Blocking Index, NMD and North Atlantic Oscillation Index, as well as the modeled melt amount and NAOI. The NMD was strongly linked with the strength of the total column water anomaly in the coastal areas. In individual summers, positive anomalies in southerly winds coincided with positive NMD anomalies. At the eastern coast, positive NMD anomalies occurred under stronger downslope winds, suggesting that subsidence heating dominated over cold‐air advection from the inner ice sheet. Differences between the summers of extreme melt in 2012 and minimal melt in 2013 were partly explained by the larger (smaller) occurrence of air masses of southwesterly (southeasterly) origin in 2012 than 2013 at northeastern Greenland. For the 15‐year period, the occurrence of northeasterly air‐mass origin at Summit was the variable with strongest (negative) correlation with the maximum melt extent.
影响因子：
3.4
作者：
D. Wilton;A. Jowett;Edward Hanna;G. Bigg;M. Broeke;X. Fettweis;P. Huybrechts
通讯作者：
D. Wilton;A. Jowett;Edward Hanna;G. Bigg;M. Broeke;X. Fettweis;P. Huybrechts
影响因子：
4.6
作者：
J. Sedlar;M. Tjernström;T. Mauritsen;M. Shupe;I. Brooks;P. Persson;C. Birch;C. Leck;A. Sirevaag;M. Nicolaus;M. Nicolaus
通讯作者：
J. Sedlar;M. Tjernström;T. Mauritsen;M. Shupe;I. Brooks;P. Persson;C. Birch;C. Leck;A. Sirevaag;M. Nicolaus;M. Nicolaus