The role of climate change in the occurrence of algal blooms: Lake Burragorang, Australia

The three-dimensional hydrodynamic Estuary, Lake and Coastal Ocean Model (ELCOM) was coupled to the ecological Computational Aquatic Ecosystem Dynamics Model (CAEDYM) and to an underflow model to simulate the fate of the constituents from three flood underflow events in Lake Burragorang, Australia, in order to verify the changes in the hydrodynamical behavior that could lead to an algal bloom when the lake water level is low as a consequence of climate change. Simulated patterns of temperature, dissolved oxygen, and turbidity compared well with field data. The ELCOM-CAEDYM simulations demonstrated that the vertical excursion induced by an intrusion depended on the volume of the lake before the arrival of the inflow, on the volume of water inserted by the inflow, and on the proximity between the top insertion of the inflow and the surface layer of the lake. When the water level was low and the inflow volume was high, the underflow constituents mixed into the surface layer and triggered a major algal bloom.

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