夏季太湖水体势能异常的空间分异特征及其机制

基于2013年6月7日~8月28日在大浦口、梅梁湾、避风港、平台山及小雷山附近湖体中获取的气象数据及水温廓线,探讨了太湖水体势能异常的空间特征及其可能机制.结果表明:太湖水体势能异常不仅存在日变化,而且呈现明显的空间差异:湾区附近的梅梁湾和避风港,较易形成相对稳定的水体层化,且可能维持多天;而位于西岸的大浦口、湖心区的平台山及湖南部的小雷山区域的水体势能异常呈典型的日分层现象,即白天可能形成层化,晚间基本消失.水体获得的热量存在空间差异,但差异度较小,而动力混合作用的空间差异明显.动力混合作用的空间差异是造成水体势能异常或层化空间分异的主要成因.

Spatial differentiation of water potential energy anomaly in Taihu Lake in summer and its mechanism

Based on the meteorological data and water temperature profile in Dapukou, Meiliang Bay, Bifenggang, Pingtaishan and Xiaoleishan from 7 June to 28 August in 2013, the spatial characteristics and its possible mechanism of the potential energy anomaly were studied. The potential energy anomaly presented not only diurnal variation, but also significant spatial differentiation: there was relatively stable stratification and the stratification had been not destroyed for some days in Bay, such as Meiliang Bay and Bifenggang; there was typically diurnal stratification in open water region, such as Dapukou, Pingtaishan and Xiaoleishan. Namely, the stratification may be established in daytime and destroyed in nighttime. There was relatively weak spatial differentiation of the heat flux received by water and significant spatial heterogeneity of mixing effect resulted from dynamics. The spatial heterogeneity of the potential energy anomaly or stratification was primarily caused by the spatial differentiation of dynamic mixing effect.