Temporal and spatial characteristics of potential energy anomaly in Lake Taihu.

Abstract

In this study, water temperature and meteorological data in Lake Taihu from June 11 to July 6, 2013, are collected to calibrate and verify the unstructured grid finite-volume community ocean model (FVCOM) coupled with a heat exchange module. The spatial and temporal variations of potential energy anomalies (PEA) in the lake, simulated by the calibrated FVCOM, are analyzed to explore the stratification and de-stratification processes in water body. The temporal variation of PEA primarily follows the diurnal cycles of solar radiation, while the spatial heterogeneity of PEA is jointly determined by solar radiation and vertical shear of horizontal velocity coupled with the topography of the lake. The maxima of PEA in the lake are not greater than 4J/m3 in the summer and even smaller along shore regions and near the Pingtaishan station. This study is helpful to improve understanding of the effect of physical processes on the algae bloom in Lake Taihu.