DYNAMIC INSTABILITY OF LARGE-SCALE SEA SURFACE TEMPERATURE (SST) DISTURBANCE AND THE FORMATION OF SEA SURFACE TEMPERATURE ANOMALY (SSTA)

This paper proposes that the formation of SSTA is a dynamic instability of large-scaleSST disturbance. Using a linear coupled air-sea model, in which the baroclinic atmosphere isdivided into two levels and the ocean is a mixture layer and a deep water layer, we obtainphysical conditions as well as spatial and temporal seales for the growing of SST disturbance.The major factors for the growing of SST disturbance include Sverdrup transportation, heatexchange between mixture layer and deep water, and modulation effect of clouds on solarradiations. The main horizontal scales of growing SST disturbance range from 3000 to 6000km and its temporal scales are several months. even soveral years. On the basis of thesetheoretical results, the causes for the formation of SSTA are also discussed.     

大尺度海温扰动的动力不稳定与海温异常的形成

本文提出了海温异常是海温扰动的动力不稳定现象所形成的。文中利用一个两层斜压大气和两层海洋的模式,在线性化的情况下,得到了海温扰动发展的物理条件和时空尺度。海温扰动发展最主要的物理因子是Sverdrup输送、混合层与深水层之间的热交换和云对短波辐射的调节作用。扰动发展的主要水平尺度是3-6千公里,时间尺度是几个月甚至几年。