Seasonal decay and break-up of sea ice in the Arctic coastal domain

北极沿海地区海冰的季节性衰退和破裂

• 批准号: RGPIN-2020-05329
• 负责人: Ehn, Jens
• 金额: $ 1.82万
• 依托单位: University of Manitoba
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=717595
• 关键词: Seasonal; decay; break; up; sea

The decline of Arctic sea ice is one of the most prominent signals of climate change on Earth. Particularly the thick, multiyear ice is in rapid decline, indicating that the state of the Arctic Ocean is undergoing a shift towards a seasonal sea ice regime with new emerging open water areas. The landfast ice fringing the shores freezes up later, breaks up earlier, and is generally becoming less safe. Coastal communities around the Arctic have raised concern as they depend on the stability of the landfast ice for their subsistence hunting and travel. Less sea ice and more open water allows sunlight to heat the ocean and melt ice more rapidly, resulting in more open water this is the well-known ice-albedo feedback loop. The Arctic Ocean is also receiving more freshwater from river runoff, glacier meltwater and precipitation. Thus, the Arctic marine environment is becoming both warmer and fresher, and the reduction in sea ice is linked to increased storminess, coastal erosion and permafrost melt. My research involves fieldwork in Arctic coastal communities, in ice camps, or onboard ships to observe and better understand the processes and climate feedbacks that control the seasonal and interannual change of Arctic sea ice. The focus of this research program is on the seasonally sea ice covered coastal and nearshore environment, or the so-called costal domain. The research objectives are to investigate: 1) the interplay between the components of the surface energy balance and the melt progression of the sea ice; 2) how ice melting affects the propagation of sunlight through the sea ice into the water column; and 3) how the seasonal decay and breakup of sea ice in the coastal and nearshore zone has changed over the last decades as a function of thermal decay (i.e., objectives 1 and 2) and external influences from the adjacent terrestrial (warm air advection, impurities, freshwater runoff) and marine domains (oceanic heat, waves, tides, storm surges). With these objectives, I will tackle phenomena that are at the heart of understanding the changing Arctic coastal sea ice environment, which is of particular concern to local residents and land users. Our ability to predict how the marine- and climate system in the Arctic will change, and how ecosystems will respond, rests on understanding the interactions between the sea ice, the ocean and the surrounding terrestrial system. The three objectives of this research program are interrelated, and as such designed as collaborative yet distinct individual projects for 6 PhD, 4 MSc and 5 BSc students. The outcome of this research will advance our knowledge of sea ice processes and climate feedbacks in the new emerging state of the Arctic Ocean, train students in Arctic marine research, involve northern residents in the research, and ultimately, benefit Northerners by improving climate predictions and process understanding that will help communities and various levels of government adapt to climate change.

北极海冰的衰落是地球气候变化最突出的信号之一。尤其是厚，多年的冰正在迅速下降，这表明北极海的状态正朝着新兴的开放水域区域转向季节性海冰制度。陆地边缘的陆地冰正在稍后冻结，更早地分解，并且通常变得不太安全。北极附近的沿海社区引起了人们的关注，因为他们依靠Landfast Ice的稳定性来狩猎和旅行。更少的海冰和更多的开放水使阳光更快地加热海洋，并更快地融化冰，从而产生更多的开放水，这是众所周知的冰 - 阿尔贝托的反馈回路。北极海也正在从河流径流，冰川融化和降水中获得更多的淡水。因此，北极海洋环境既变暖又更新鲜，海冰的减少与暴风雨，沿海侵蚀和永久冻土融化有关。 我的研究涉及在北极沿海社区，冰上营地或船上船上的实地考察，以观察和更好地了解控制北极海冰季节性和年度变化的过程和气候反馈。该研究计划的重点是季节性海冰覆盖的沿海和近岸环境，或所谓的costal域。研究目标是研究：1）表面能量平衡的组成部分与海冰的熔体进展之间的相互作用； 2）冰熔化如何影响阳光通过海冰传播到水柱中； 3））在过去的几十年中，海冰的季节性衰变和海冰破裂是如何随着热衰变（即目标1和2）的函数以及相邻地面陆地（温暖的空气对流，杂质，淡水径流）和海洋域（海洋热量，海洋热量，波浪，潮汐，潮汐）的外部影响而发生了变化。 有了这些目标，我将解决了解不断变化的北极海上冰环境的核心，这对当地居民和土地用户特别关注。我们预测北极中海洋和气候系统的能力将如何变化，以及生态系统将如何反应，取决于了解海冰，海洋和周围陆地系统之间的相互作用。该研究计划的三个目标是相互关联的，并且设计为6份博士学位，4个MSC和5名BSC学生的协作但不同的个人项目。这项研究的结果将提高我们对北极海洋新兴状态下海冰过程和气候反馈的了解，培训北极海洋研究的学生，使北方居民参与研究，并最终通过改善气候预测和流程的理解来使北方人受益，这将有助于社区和各级政府的政府适应气候变化。