Wind effects change in Taihu Lake with climate change background

Large shallow lakes globally are threatened by eutrophication, and climate change is believed to aggregate the situation. Wind, as the most important momentum source and the major contributor to consistently change the hydrodynamic patterns inside the large shallow lakes, is highly susceptible to climate change. Taihu Lake, which is the 3^rd largest shallow lake in China and pertains crucial social and economic values, is chosen in this study as an example. Due to climate change, the wind condition of Taihu Lake shows a significantly decreasing trend of wind speed and the frequency of extreme wind events. Previous studies have paid little attention to the climate change effects on wind hydrodynamics and its implications on water quality has not yet been thoroughly described. Here in this study, we use a well-calibrated and validated three-dimensional Delft3D model to investigate the spatial and temporal heterogeneity of wind induced hydrodynamics and its water quality implications with climate change. The model results give a prediction of less current speed, lower wave height and bottom shear stress compared to the reference scenario, while the three dimensionality of flow field remains. Further, water age is used to demonstrate the influence of external nutrient sources, i.e. the input from adjacent river networks in the basin. Large water ages are observed and potentially it would enhance the accumulation of nutrients and deterioration of water quality.