Collaborative Research: A synthesis of rapid meltwater and ice discharge changes: large forcings from the ice with impacts on global sea level and North Atlantic freshwater budgets

合作研究：快速融水和冰排放变化的综合：来自冰的巨大强迫对全球海平面和北大西洋淡水预算的影响

基本信息

批准号：
0531270
负责人：
Ian Joughin
金额：
$ 14.94万
依托单位：
University of Washington
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2005
资助国家：
美国
起止时间：
2005-09-01 至 2009-08-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=0531270&HistoricalAwards=false
关键词：
Collaborative Research synthesis rapid meltwater

项目摘要

AbstractFreshwater discharge from the Greenland ice sheet has a direct and immediate effect on global sea level, has the potential to impact global climate by perturbing nearby sensitive regions of oceanic deep-water formation, and is an important but as yet poorly quantified part of the pan-Arctic water balance. The investigators will synthesize a range of extant data sets using numerous methods. Remote sensing and atmospheric modeling calibrated by surface data accurately reveal a spatially resolved history of surface melting on Greenland over decades, and coastal weather stations extend observations to more than a century. Sophisticated transfer techniques, including nonlinear approaches, will be used to downscale from these instrumental data to specific ice-core records of melt, learning how the widespread signal is archived. The derived transfer functions, the centuries-long ice-core records, and the century-length coastal-station records then will allow upscaling to determine meltwater variability over longer times than now available. Remotely sensed changes in ice shelves/tongues and outlet-glacier flow speeds will be combined with the contemporaneous histories of surface melting, and analyzed using diagnostic ice-flow modeling incorporating longitudinal stresses to learn how meltwater variability and ice shelf changes force ice-flow variability. If successful diagnosis is achieved, then the longer melt history from the ice-cores can be used to estimate the ice-flow variability over the same interval; the relations between ice-flow and melt changes also can be used prognostically in assessing future changes in the ice sheet affecting freshwater fluxes.

摘要：格陵兰冰盖的淡水排放对全球海平面有直接、即时的影响，有可能通过扰动附近海洋深水形成的敏感区域来影响全球气候，并且是整个海洋冰盖的一个重要但尚未量化的部分。 - 北极水平衡。研究人员将使用多种方法综合一系列现有数据集。通过表面数据校准的遥感和大气模型准确地揭示了格陵兰岛数十年来表面融化的空间解析历史，沿海气象站将观测时间延长到一个多世纪。复杂的传输技术，包括非线性方法，将用于将这些仪器数据缩小到特定的冰芯融化记录，了解如何存档广泛的信号。导出的传递函数、长达几个世纪的冰芯记录和长达一个世纪的沿海站记录将允许升级，以确定比现在更长的时间内融水的变化。遥感的冰架/冰舌和出口冰川流速的变化将与同期表面融化历史相结合，并使用结合纵向应力的诊断冰流模型进行分析，以了解融水变化和冰架变化如何迫使冰流变化。如果成功诊断，则可以使用冰芯较长的融化历史来估计同一时间间隔内的冰流变化；冰流和融化变化之间的关系也可用于预测影响淡水通量的冰盖未来变化。