Collaborative Research: The combined influence of sea ice and snow cover on Northern Hemisphere atmospheric climate variability

合作研究：海冰和积雪对北半球大气气候变率的综合影响

• 批准号: 1503966
• 负责人: Dara Entekhabi
• 金额: $ 28.42万
• 依托单位: Massachusetts Institute of Technology
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-08-15 至 2019-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1503966&HistoricalAwards=false
• 关键词: Collaborative; Research; combined; influence; sea

Arctic snow and ice form an integral part of the climate system. They have undergone unprecedented changes within the past decade. Initial studies on the potential remote and larger scale influences of their variability have often been inconclusive and even contradictory. In a recent review article, the principal investigators (PIs) of this proposal hypothesized that sea ice and snow cover can combine to force large-scale atmospheric variability. This project focuses on analyzing reanalysis datasets and model output from targeted numerical modeling experiments in order to understand the physical pathways linking sea ice and snow cover variability with atmospheric climate variability. This variability may, in turn, influence mid-latitude weather on seasonal time scales. Understanding such processes is anticipated to improve weather prediction on similar time scales, with consequent benefits to the energy, farming, and reinsurance industries, amongst others. The project will contribute to STEM manpower development through providing support for the training of a graduate student, entrainment of undergraduate students into scientific research, and development of a short course of climate prediction. Finally, the project will promote international collaboration with a German research institute.Prescribed sea ice and snow cover perturbation experiments with the Whole Atmosphere Community Climate Model (WACCM) will lead to a quantitative assessment of the physical pathways between sea ice, snow cover and the initiation and maintenance of atmospheric variability, particularly in winter, that cannot be accomplished using statistical analysis alone. The use of a high-top model, which has only recently become available, to study the influence of sea ice and snow cover on the hemispheric winter circulation is novel to this proposal. In parallel, the PIs will collaborate with colleagues running similar experiments with ECHAM6. They will further analyze reanalysis atmospheric data, to test hypotheses about the combined role of sea ice and snow cover in climate variability learned from the model output. The proposed project will analyze the combined impact of sea ice and snow cover anomalies on atmospheric climate variability. This will improve understanding of the atmospheric response associated with changes in sea ice and snow cover, and lead to a quantitative assessment of the links between high-latitude and lower-latitude climates as well as enable improved climate predictions. The proposed research focuses specifically on the combined role of sea ice and snow cover in the initiation and maintenance of the dominant mode of high-latitude atmospheric variability, i.e. the annular mode. Modulation of the annular mode is hypothesized to be a key physical mechanism for climate feedback in high latitudes and is the dominant mode of variability in the mid-latitudes including the industrial centers of the United States, Europe and Asia. The conceptual framework developed in this project will be applied in an operational seasonal forecast model at the end of the project.

北极雪和冰构成气候系统的组成部分。 在过去的十年中，他们发生了前所未有的变化。 关于其可变性的潜在远程和较大规模影响的初步研究通常尚无定论甚至矛盾。 在最近的评论文章中，该提案的首席研究人员（PIS）假设海冰和积雪可以结合起来迫使大规模的大气变异性。 该项目着重于分析有针对性的数值建模实验的重新分析数据集和模型输出，以了解将海冰和雪连接的物理途径与大气气候变异性联系起来。 反过来，这种可变性可能会影响季节性时间尺度的中纬度天气。 预计理解此类过程将改善类似时间尺度上的天气预测，从而对能源，农业和再保险行业等等。 该项目将通过为研究生的培训提供支持，本科生纳入科学研究的培训以及发展气候预测的简短过程，从而为STEM人力发展做出贡献。最后，该项目将促进与德国研究所的国际合作。规定的海冰和雪覆盖了整个大气层社区气候模型（WACCM）的扰动实验（WACCM）将对海冰，雪覆盖和维持大气变异性之间的物理途径进行定量评估，尤其是在冬季，无法实现统计分析。 该提议的新型高顶模型直到最近才可以研究海冰和雪覆盖对半球冬季循环的影响。 同时，PIS将与与ECHAM6进行类似实验的同事合作。 他们将进一步分析重新分析的大气数据，以测试有关海冰和雪覆盖在从模型输出中学到的气候变异性中的合并作用的假设。 拟议的项目将分析海冰和雪的综合影响涵盖异常对大气气候变化的影响。 这将提高人们对与海冰和积雪变化相关的大气反应的理解，并导致对高纬度和较低纬度气候之间的联系进行定量评估，并能够改善气候预测。 拟议的研究专门针对海冰和雪覆盖在高纬度大气变异性的主要模式（即环形模式）中的综合作用。 假设环形模式的调节是高纬度地区气候反馈的关键物理机制，并且是中期的主要变异模式，包括美国，欧洲和亚洲的工业中心。 该项目中开发的概念框架将在项目结束时的运营季节性预测模型中应用。