Development of Nearshore Hypoxia in Central Lake Erie; Field Observations and 3D Numerical Modelling

Session: 45. - Hypoxia: Causes, Impacts, and Management

Reza Valipour, Environment and Climate Change Canada, [email protected]
Luis Leon, Environment and Climate Change Canada, [email protected]
Ram Yerubandi, Environment Canada, Water Sciences & Technology, Canada Centre for Inland Waters, [email protected]
Todd Howell, Ontario Ministry of the Environment, Env. Monitoring & Reporting Br, [email protected]

Abstract

Offshore hypoxia is a seasonal feature of central Lake Erie. Hypoxic conditions have the potential to also develop in the nearshore waters of central Lake Erie in response to strong winds via upwelling events. The interaction of wind-induced currents and the nearshore bathymetry determine the extent of nearshore zone affected by the offshore hypoxic waters. We investigate the development of nearshore hypoxic zone in central Lake Erie using a calibrated high-resolution three-dimensional water quality model and field data analysis. The model quantifies the extents of nearshore hypoxic zones via frequent upwelling events, which are driven by favorable winds every 5- 10 days and cover almost the entire northern central basin during the summer. In addition, we describe the hydrodynamics underpinning the development of hypoxic nearshore waters, and its impacts on the nearshore nutrient dynamics including total phosphorus,  soluble reactive phosphorus and total nitrogen.

1. Keyword
Lake Erie

2. Keyword
hydrodynamic model

3. Keyword
ecosystems

4. Additional Keyword
hypoxia