北极高密集度冰区海冰加速融化机理及其与中高纬度风暴活动的联系

近年来北极海冰加速融化及其对中高纬度天气气候的影响引起广泛关注和争议。北极海冰变化的最大变率出现在高密集度海冰的边缘区域，目前北极放大的正反馈机制多是针对该区域的，但哪种机制起主要作用尚未达成共识。申请人的预研究发现北极高密集度冰区（气候平均海冰密集度大于90%的区域，简称HSIC）海冰的变化几乎主导了整个北冰洋海冰的变化，且在近年来频繁出现海冰密集度极端降低事件，反映出HSIC海冰的加速融化特征，这种北极中央区HSIC海冰加速融化的物理机制由于耦合了风暴活动的动力影响和反馈，可能不同于边缘区的反馈机制。本项目将从研究北极HSIC海冰密集度极端降低事件为切入点，揭示HSIC海冰加速融化的时空变化规律，阐明其可能的物理机制，探究北极HSIC海冰融化与中高纬度风暴活动的可能联系。研究结果将加深人们对北极放大机理及其气候效应的科学认识，并对未来开拓北极中央航道和“冰上丝绸之路”提供重要科学依据。

In recent years, the accelerated melting of Arctic sea ice and its effect on the weather climate in middle and high latitudes have aroused wide attention and controversy. The maximum variability of Arctic sea ice changes occurs in the marginal zone of multi-year ice or high sea ice concentration (HSIC), that is, the seasonal melting area. Currently, most of the mechanisms proposed are the positive feedback mechanism in this area, and no consensus has been reached on which mechanism plays a major role. The pre-study of the applicant found that change of sea ice in HSIC (climatological mean of SIC is more than 90%) area almost dominates the change of the whole Arctic sea ice. And in recent years, frequent SIC extremely low events (SELE) reflect accelerated melting characteristics of sea ice in HSIC area. The physical mechanisms of accelerated melting of sea ice in central Arctic HSIC region may be different from the feedback mechanism in the marginal ice zone. This project will start from the study of the Arctic SELE, reveal the spatiotemporal variation of the accelerated sea ice melting in HSIC area, clarify its possible physical mechanism, and explore the possible connection between the sea ice melting in the Arctic HSIC area and the mid-high latitude storm activities. The research results will deepen the scientific understanding of the Arctic amplification mechanism and its climate effects, and provide important scientific basis for the future development of the Arctic central pathways and the "ice silk road".