格陵兰岛冰盖消融时空特征(2003~2015年)及其对海平面上升的贡献  

Spatio-Temporal Characteristics of Ice Sheet Melting in Greenland and Contributions to Sea Level Rise from 2003 to 2015

作　　者：彭桢燃 胡正旺[1,2] 王林松[1,2] 陈超[1,2] 付争妍[1,2] Peng Zhenran;Hu Zhengwang;Wang Linsong;Chen Chao;Fu Zhengyan(Hubei Subsurface Multi-Scale Imaging Key Laboratory,China University of Geosciences,Wuhan 430074,China;Institute of Geophysics&Geomatics,China University of Geosciences,Wuhan 430074,China)

机构地区：[1]中国地质大学地球内部多尺度成像湖北省重点实验室,湖北武汉430074 [2]中国地质大学地球物理与空间信息学院,湖北武汉430074

出　　处：《地球科学》2021年第2期743-758,共16页Earth Science

基　　金：国家自然科学基金面上项目(Nos.41874090,41774091);中央高校基本科研业务费专项资金资助项目(No.CUGL170204)。

摘　　要：研究格陵兰冰盖(GrIS)质量变化异常速率可以帮助了解异常气候事件驱动海平面变化的机制.聚焦于2010~2012年GrIS质量变化的异常速率,及其对海平面指纹(SLF)和相对海平面(RSL)变化的贡献.通过联合2003~2015年GRACE月重力场数据和表面质量平衡(SMB)数据,采用mascon拟合法及网格尺度因子恢复泄漏,获得了6个流域的质量变化时空分布.基于海平面变化方程(SLE)并考虑负荷自吸引效应估算了SLF的空间分布.结果表明,2003~2015年间GrIS总质量变化速率分别为-288±7 Gt/a及-275±1 Gt/a;而在2010~2012年间速率相应地增加至-456±30 Gt/a及-464±38 Gt/a,该时期格陵兰西北海岸及东南沿海地区呈现出大量冰盖融化,其对海平面的贡献变化呈现倒"V"型(即先升后降),而全球平均海平面变化呈现出明显的正"V"型(即先降后升).另外,GrIS融化对海平面的贡献约为31%,造成全球平均RSL增加了0.07 cm/a,而对斯堪的纳维亚及北欧地区的RSL贡献为-0.6 cm/a,GrIS融化造成的远海地区RSL上升速率比全球平均RSL速率高近30%.Studing the abnormal mass change rate of Greenland ice sheet(GrIS)can help us understand the drivers of sea level change due to the abnormal climate events.Therefore,in this paper it focuses on the anomalous rate of GrIS mass change in2010-2012 and its contributions to SLF and relative sea level(RSL)changes.By combining the 2003-2015 GRACE monthly gravity field data and surface mass balance(SMB)data,the spatio-temporal distributions of the mass change of the six extended sub-basins are estimated based on the mascon fitting and the grid scale factors.Afterwards,it obtains the spatial distribution of the SLF based on the sea level equation(SLE)and considering the self-attraction and loading effect.The results indicate that during2003-2015,the total mass change rates of GrIS were-288±7 Gt/a and-275±1 Gt/a as derived from scaled GRACE and SMB results respectively;and the trend increased to-456±30 Gt/a and-464±38 Gt/a correspondingly during 2010-2012,when the northwest coast and the southeast coast showed a large number of melting.And the contributions of GrIS to sea level showed an inverted"V"type(i.e.,first rise and then fall),while the global mean sea level change showed a distinct positive"V"type(i.e.,first drop and then rise).Between 2003 and 2015,GrIS contributed approximately 31%of total terrestrial water reserves(converted to sea level rise),and a global average RSL increased by 0.07 cm/a,while the contribution to the RSL of Scandinavia and the Nordic region was-0.6 cm/a.In addition,the far-field RSL rising rate due to the melting of GrIS is nearly30%higher than the global average.Meanwhile,in this paper it proves that the far-filed peak increase is less dependent on the accurate pattern of the self-attraction and loading.

关 键 词：GRACE 表面质量平衡 格陵兰岛冰盖 异常融化 海平面指纹 海洋水文学 

分 类 号：P731[天文地球—海洋科学]