北极各关键区海冰对东亚夏季风影响的机理研究

The precipitation over East Asia is dominated by the East Asian summer monsoon (EASM), which is the overwhelming climate feature in this area. Its anomalies have dramatic influence on our agriculture, industry and national economy. Nowadays it is still a challenge to predict the EASM for climate community, which relies heavily on better understanding of EASM variability. The the correlation between tropical Ocean and EASM become weaken during last 30 years. Meanwhile, the relationship between EASM and some high latitude signals become strengthen. Early studies also indicated that the boreal spring Arctic sea ice has close connections with summer precipitation in East Asia. Although many studies suggested that the boreal spring Arctic sea ice is connected to summer precipitation in East Asia, the mechanism how different key sector of spring Arctic sea ice influences the summer climate over East Asia is not fully understood. The main purpose of this study is to address and the process of the climate impact of reduced spring Arctic sea ice in different key sector on East Asian summer monsoon, by the AGCM (Atmosphere General Circulation Model) and AOGCM (Atmosphere-Ocean General Circulation Model) simulations that carried out by ABOT (Atmospheric Bridge and Oceanic Tunnel) technology, and to investigate the potential mechanism for this multi-season connection.

东亚夏季风异常对我国工农业生产以及国民经济会产生重大影响。而由于东亚夏季风的复杂性，准确地预报东亚夏季降水变率，至今仍然是个难题。近30年来热带海洋的前期信号与东亚夏季降水的相关性已大大衰减，其指示作用也相对降低。而中高纬度的前期信号与东亚夏季降水的相关性有所增加。研究表明近30年来春季北极海冰与东亚夏季降水存在较为密切的联系。而不同海区海冰的气候效应以及指示作用也不尽相同。尽管诸多研究均指出春季北极海冰与东亚夏季降水异常存在联系。但是春季北极各关键区海冰是如何影响东亚夏季气候的物理机制目前还未被仔细研究和阐述。本项目从海-冰-气耦合的角度，将观测资料和海-冰-气耦合模式的敏感试验相结合，探讨春季海冰是如何将影响持续到夏季，并深入研究各关键海区海冰对东亚夏季降水产生影响的可能物理机制。