Role of radiative forcing on the sea ice melt-growth cycle in a changing Arctic marine environment - Northern Research Supplement

不断变化的北极海洋环境中辐射强迫对海冰融化生长循环的作用 - 北方研究增刊

• 批准号: 444872-2013
• 负责人: Ehn, Jens
• 金额: $ 1.27万
• 依托单位: University of Manitoba
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Northern Research Supplement
• 财政年份: 2017
• 资助国家: 加拿大
• 起止时间: 2017-01-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=628557
• 关键词: Role; radiative; forcing; sea; ice

The Arctic sea ice cover is in rapid decline due to global warming with yet another new record low reached in 2012. The diminishing ice cover is having a discernible impact on the polar marine environment. However, the extent of this impact on future changes to climate, carbon cycling and ecosystems remains uncertain. At the root is how surface radiative forcing affects changes in sea ice properties, and how these changes in turn modulate the forcing. Such interactions form the base of complex climate feedbacks operating in the Arctic. Considering the vastness of the area of sea ice (~10 million km2 or roughly the size of Canada) that forms and then melts each year, the importance of a comprehensive understanding of the processes driving this cycle cannot be overstated. In this Northern Research Supplement proposal, I seek the additional funds required to support both field camp and ship-based sea ice research in the Canadian Arctic. The objective of the proposed research is to investigate how the melting of the sea ice is partitioned between surface, interior and bottom, and how much heat is retained in the upper ocean layers where it can delay fall freeze-up and slow ice growth. Our ability to predict future climate change and variability rests on understanding these processes. The focus is on radiative forcing and associated feedbacks as these interactions exert a dominant control on the surface energy balance in the Arctic. I will also utilize information from how radiation interacts with sea ice and seawater constituents to develop non-invasive optical methods to infer physical, biological and chemical properties in real-time at high spatial and temporal resolutions. The proposed research will advance our knowledge of sea ice processes and climate feedbacks, develop new optical techniques that addresses logistical challenges in data collection, train new students in Arctic environmental research and ultimately, benefit northerners by improving climate predictions that will help communities and various levels of government adapt to climate change.

由于全球变暖，北极海冰覆盖面积正在迅速减少，2012 年又创下历史新低。冰盖面积的减少对极地海洋环境产生了明显的影响。然而，这种影响对未来气候、碳循环和生态系统变化的影响程度仍不确定。根本问题是表面辐射强迫如何影响海冰特性的变化，以及这些变化如何反过来调节强迫。这种相互作用构成了北极复杂气候反馈的基础。考虑到每年形成然后融化的海冰面积之大（约 1000 万平方公里，或大约相当于加拿大的面积），全面了解驱动这一循环的过程的重要性怎么强调也不为过。在这份北方研究补充提案中，我寻求支持加拿大北极地区野外营地和船基海冰研究所需的额外资金。拟议研究的目的是调查海冰的融化如何在表面、内部和底部之间分配，以及有多少热量保留在上层海洋层中，从而延缓秋季冻结并减缓冰的生长。我们预测未来气候变化和变异的能力取决于对这些过程的理解。重点是辐射强迫和相关反馈，因为这些相互作用对北极地表能量平衡发挥主导控制作用。我还将利用辐射如何与海冰和海水成分相互作用的信息来开发非侵入性光学方法，以高空间和时间分辨率实时推断物理、生物和化学特性。拟议的研究将增进我们对海冰过程和气候反馈的了解，开发新的光学技术来解决数据收集中的后勤挑战，培训北极环境研究的新生，并最终通过改进气候预测使北方人受益，从而帮助社区和各级政府适应气候变化。