Towards a marginal Arctic sea ice cover

走向北极边缘海冰覆盖

基本信息

批准号：
NE/R000263/1
负责人：
Michel Tsamados
金额：
$ 14.66万
依托单位：
University College London
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2018
资助国家：
英国
起止时间：
2018 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=NE%2FR000263%2F1
关键词：
Towards marginal Arctic sea ice

项目摘要

Recent observed changes in the Arctic have become a 'poster child' for global climatic changes, particularly because the summer sea ice extent has shrunk rapidly over the past 35 years. This retreat of the sea ice has led to growth of trans-Arctic shipping and plans to extract minerals and fossil fuels from the ocean floor. The latest assessment of the Intergovernmental Panel on Climate Change (IPCC) concluded that it was likely that the Arctic would become reliably ice-free by 2050 assuming greenhouse gas emissions continue to increase. However, the climate simulations used by the IPCC often fail to realistically capture large scale properties of the Arctic sea ice, such as the extent, variability and recent trends. Therefore, there is a need to improve simulations of Arctic sea ice to provide better understanding of the recent observed changes and credible projections of the future to help assess risks and opportunities and inform important policy decisions about adaptation and mitigation. Observations of the Arctic have improved in recent years with new satellites measuring sea ice properties from space. These satellites reveal not only that the extent and thickness of the Arctic ice cover is reducing in all seasons but that the Marginal Ice Zone (MIZ), a region of low ice area concentration consisting of a relatively disperse collection of small floes, has grown.Model projections indicate the MIZ will grow from around 10% to 80% of the summer sea ice cover by 2050, exposing a hitherto relatively quiescent Arctic Ocean to the atmosphere. Nonlinear interactions between the air, ice, and ocean that magnify or diminish change, known as feedbacks, associated with a reduced and marginal sea ice cover will emerge or assume dominance in the coming years. Many of these feedbacks are either entirely absent or inadequately captured in current models. For example, not included is the feedback whereby the creation of smaller floes due to ice melt or breakup under ocean wave stress promotes further lateral melt and propagation of waves deeper into the pack, further enlarging the MIZ. Because existing climate models oversimplify these feedbacks, their utility for understanding and predicting variability and change in the Arctic is compromised. This leads to impairment of climate model accuracy at lower latitudes also, due to errors in meridional atmospheric and oceanic circulations as well as ice export from the Arctic. We will investigate processes controlling evolution of the MIZ using existing and new observations. We will include physics of wave-ice interaction, ice breakup and melt, and floe collisions into ice, ocean, and climate models. We will use these models, constrained and verified with new observations, to explore feedbacks between the sea ice, ocean, and atmosphere using a series of numerical experiments. We will quantify the impact of the increase in the MIZ on the Arctic physical climate, and explore the processes responsible for the projected loss of Arctic sea ice.

最近观察到的北极变化已成为全球气候变化的“典型”，特别是因为夏季海冰范围在过去 35 年里迅速缩小。海冰的退缩导致了跨北极航运的增长，并计划从海底提取矿物和化石燃料。政府间气候变化专门委员会 (IPCC) 的最新评估得出的结论是，假设温室气体排放继续增加，到 2050 年，北极可能会可靠地无冰。然而，IPCC 使用的气候模拟往往无法真实地捕捉北极海冰的大尺度特性，例如范围、变化和近期趋势。因此，需要改进对北极海冰的模拟，以更好地了解最近观察到的变化和对未来的可靠预测，以帮助评估风险和机遇，并为有关适应和缓解的重要政策决策提供信息。近年来，随着新卫星从太空测量海冰特性，对北极的观测得到了改善。这些卫星不仅揭示了北极冰盖的范围和厚度在所有季节都在减少，而且边缘冰区（MIZ）——一个由相对分散的小浮冰集合组成的低冰区集中区域——已经扩大。模型预测表明，到 2050 年，MIZ 将从夏季海冰覆盖的 10% 左右增长到 80%，从而将迄今为止相对静止的北冰洋暴露在大气中。空气、冰和海洋之间的非线性相互作用会放大或减少变化，称为反馈，与海冰覆盖范围的减少和边缘化相关，将在未来几年出现或占据主导地位。当前模型中许多反馈要么完全不存在，要么没有充分捕获。例如，不包括反馈，即由于海浪应力下的冰融化或破裂而产生较小的浮冰，促进进一步的侧向融化和波浪向更深处传播，从而进一步扩大 MIZ。由于现有的气候模型过于简化了这些反馈，因此它们在理解和预测北极变化和变化方面的效用受到了损害。由于经向大气和海洋环流以及北极冰出口的误差，这也会导致低纬度地区气候模型的准确性受损。我们将利用现有的和新的观测结果来研究控制 MIZ 演化的过程。我们将把波冰相互作用、冰破裂和融化以及浮冰碰撞的物理学纳入冰、海洋和气候模型中。我们将使用这些模型，通过新的观测进行约束和验证，通过一系列数值实验来探索海冰、海洋和大气之间的反馈。我们将量化 MIZ 的增加对北极自然气候的影响，并探索导致北极海冰预计消失的过程。

项目成果

期刊论文数量（9）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Retrieving Sea Ice Drag Coefficients and Turning Angles From In Situ and Satellite Observations Using an Inverse Modeling Framework

使用逆向建模框架从原位和卫星观测中检索海冰阻力系数和转向角

DOI：
http://dx.10.1029/2018jc014881
发表时间：
2019
期刊：
Oceans
影响因子：
0
作者：
Heorton H
通讯作者：
Heorton H

Impacts of climate change on Arctic sea ice

气候变化对北极海冰的影响

DOI：
10.14465/2020.arc10.ice
发表时间：
2020-01-15
期刊：
FEMS microbiology ecology
影响因子：
4.2
作者：
B. Hwang;Y. Aksenov;E. Blockley;M. Tsamados;T. Brown;J. L;y;y;D. Stevens;J. Wilkinson
通讯作者：
J. Wilkinson

Advances in altimetric snow depth estimates using bi-frequency SARAL and CryoSat-2 Ka-Ku measurements

使用双频 SARAL 和 CryoSat-2 Ka-Ku 测量进行高度积雪深度估计的进展

DOI：
http://dx.10.5194/tc-15-5483-2021
发表时间：
2021
期刊：
The Cryosphere
影响因子：
0
作者：
Garnier F
通讯作者：
Garnier F

Stress and deformation characteristics of sea ice in a high-resolution, anisotropic sea ice model.

高分辨率、各向异性海冰模型中海冰的应力和变形特征。

DOI：
http://dx.10.1098/rsta.2017.0349
发表时间：
2018
期刊：
Philosophical transactions. Series A, Mathematical, physical, and engineering sciences
影响因子：
0
作者：
Heorton HDBS
通讯作者：
Heorton HDBS

CryoSat-2 Significant Wave Height in Polar Oceans Derived Using a Semi-Analytical Model of Synthetic Aperture Radar 2011-2019

使用 2011-2019 年合成孔径雷达半解析模型得出的 CryoSat-2 极地海洋有效波高