The future of Arctic sea ice

北极海冰的未来

• 批准号: NE/X000079/1
• 负责人: Daniel Feltham
• 金额: $ 65.14万
• 依托单位: University of Reading
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FX000079%2F1
• 关键词: future; Arctic; sea; ice

Anthropogenic climate change is destroying the Arctic sea ice cover. The ice loss is erratic (variable), but scientists agree the perennial Arctic ice cover will not survive this century. The sea ice cover is a partial barrier to exchanges of heat, water, and momentum between the air above and the ocean on which it floats. The reduction in sea ice is having, and is expected to continue to have, a dominant impact on local climate and ecology, and to affect extreme weather and global climate by modification of exchanges of heat and momentum in the atmosphere and ocean with lower (European) latitudes.Climate projections, generated using complex climate models, indicate that the Arctic Ocean will become seasonally ice free in the coming decades. However, these models underestimate the strength of the link between polar warming and sea ice loss; they only achieve observed rates of ice loss with unrealistic polar warming. Observations of the Arctic have improved in recent years with new satellites, e.g. IceSat-2 and CryoSat-2, measuring sea ice properties from space, and field experiments such as MOSAiC providing detailed measurements of sea ice physical processes. These show that Arctic sea ice is becoming thinner, less extensive, more fragmented, and more seasonal. Climate models of sea ice physics, built in a time of perennial ice, inadequately represent the seasonal, fragmented nature of the emerging ice cover. We will combine different satellite data products to provide estimates of the local sea ice mass budget. These measurements, among others, will be used to provide an unprecedently stringent test of sea ice models. We will enhance our sea ice models through the incorporation of representations of physical processes observed to be important in the seasonal ice cover physics, such as an evolving floe size distribution and advanced representation of frazil ice, both of which are already seen to play a leading role in the, more seasonal, Southern Ocean sea ice cover. This project will result in a necessary upgrade to model representation of Arctic sea ice.The new sea ice physics will be brought into a full climate model, which will be used to explore their impact on the ice cover of the past few decades, and their impact on decadal predictions. Our analysis of the climate simulations will utilise ideas we have explored in simpler, more idealised models and analysis of previous climate model simulations. Our aim is to produce more realistic simulations of Arctic sea ice trends and variability in the recent past and near future, as we approach a seasonally ice-free Arctic Ocean. This project will: (i) simulate the observed rates of Arctic sea ice loss in combination with the observed rates of Arctic warming; (ii) more tightly constrain when the Arctic Ocean will become seasonally ice free; and (iii) test the hypothesis that climate models' mismatch between rates of sea ice loss and Arctic warming is a consequence of inadequate physical representation of the modern Arctic sea ice cover.

人为气候变化正在破坏北极海冰覆盖。冰损失是不稳定的（可变的），但科学家们一致认为，常年北极冰盖将无法在本世纪幸存。海冰覆盖是上方空气与其漂浮的海洋之间热量、水和动量交换的部分屏障。海冰的减少正在并且预计将继续对当地气候和生态产生重大影响，并通过改变大气和海洋与较低层（欧洲）的热量和动量交换来影响极端天气和全球气候。 ）纬度。使用复杂的气候模型生成的气候预测表明，北冰洋将在未来几十年内季节性无冰。然而，这些模型低估了极地变暖与海冰消失之间联系的强度。他们只能在不切实际的极地变暖的情况下达到观察到的冰损失率。近年来，随着新卫星的出现，对北极的观测得到了改善，例如： IceSat-2 和 CryoSat-2 从太空测量海冰特性，MOSAiC 等现场实验提供海冰物理过程的详细测量。这些表明北极海冰正在变得更薄、面积更小、更加破碎且更具季节性。海冰物理学的气候模型是在常年冰层时期建立的，不足以代表新兴冰盖的季节性、碎片化性质。我们将结合不同的卫星数据产品来提供当地海冰质量预算的估计。这些测量结果将用于对海冰模型进行前所未有的严格测试。我们将通过纳入在季节性冰盖物理中观察到的重要物理过程的表示来增强我们的海冰模型，例如不断变化的浮冰尺寸分布和碎冰的高级表示，这两者都已被视为发挥着主导作用。南大洋海冰覆盖的季节性作用更大。该项目将对北极海冰的模型表示进行必要的升级。新的海冰物理学将被纳入完整的气候模型，该模型将用于探索它们对过去几十年的冰盖的影响以及它们的影响。对十年预测的影响。我们对气候模拟的分析将利用我们在更简单、更理想化的模型中探索的想法以及对先前气候模型模拟的分析。我们的目标是，当我们接近季节性无冰的北冰洋时，对最近和不久的将来的北极海冰趋势和变化进行更真实的模拟。该项目将： (i) 结合观测到的北极变暖速率来模拟观测到的北极海冰消失速率； (ii) 更严格地限制北冰洋季节性无冰的时间； (iii) 检验以下假设：气候模型海冰消失速率与北极变暖之间的不匹配是由于现代北极海冰覆盖物理表征不充分造成的。