Keywords
1 Dimensional Model, GLM, Climate Change
Start Date
17-9-2020 1:20 PM
End Date
17-9-2020 1:40 PM
Abstract
Lakes and reservoirs are standing surface water environments known for offering several anthropic uses and environmental services. Climate conditions, sediment loads, and pollutants play expressive roles in the hydrodynamic behaviour of lakes, affecting the thermal stratification and mixing regime standards that affect directly the water quality and its availability. Therefore, the analysis of climate change scenarios allows the planning and implementation of preventive and mitigative actions, in order to promote the environments’ adaptation. Numerical models can simulate the thermal regime of lakes and reservoirs considering different boundary conditions, but often require a full extensive set of 3D information to produce accurate results. This paper intends to evaluate the capability of a 1D vertical transport model to access the impacts of different climate scenarios that can affect the thermal regime of a lake. The GLM model is a very practical tool that requires less topology information and process parameters than 2D or 3D models. The case study was focused on the Hedberg Dam, located about 90 km from Sao Paulo city, Brazil. It is a 0,2 km²-4.5m depth pond, built in the beginnings of the 19th century. Its hydrological catchment area is partially protected with some sparse urban occupations. With an hourly time-step, the model used morphology characteristics, atmospheric variables and flow as input data. The model was calibrated using water thermal profiles from high-frequency sensor data and through an automatic Particle Swarm Optimization routine. The calibration and validation of the model were performed with 2017 and 2018 observed data, for dry and wet periods. Two climate change scenarios, optimistic and pessimistic, based on Eta Regional Climate Model, were simulated considering changes in radiation, air temperature, wind, precipitation and flow. The results indicate changes in the thermal profiles regime, with increasing occurrence of mixing events and variations on the stratification patterns.
Assessing the Impacts of Climate Change Scenarios Over a Tropical Lake Through a 1DV Model
Lakes and reservoirs are standing surface water environments known for offering several anthropic uses and environmental services. Climate conditions, sediment loads, and pollutants play expressive roles in the hydrodynamic behaviour of lakes, affecting the thermal stratification and mixing regime standards that affect directly the water quality and its availability. Therefore, the analysis of climate change scenarios allows the planning and implementation of preventive and mitigative actions, in order to promote the environments’ adaptation. Numerical models can simulate the thermal regime of lakes and reservoirs considering different boundary conditions, but often require a full extensive set of 3D information to produce accurate results. This paper intends to evaluate the capability of a 1D vertical transport model to access the impacts of different climate scenarios that can affect the thermal regime of a lake. The GLM model is a very practical tool that requires less topology information and process parameters than 2D or 3D models. The case study was focused on the Hedberg Dam, located about 90 km from Sao Paulo city, Brazil. It is a 0,2 km²-4.5m depth pond, built in the beginnings of the 19th century. Its hydrological catchment area is partially protected with some sparse urban occupations. With an hourly time-step, the model used morphology characteristics, atmospheric variables and flow as input data. The model was calibrated using water thermal profiles from high-frequency sensor data and through an automatic Particle Swarm Optimization routine. The calibration and validation of the model were performed with 2017 and 2018 observed data, for dry and wet periods. Two climate change scenarios, optimistic and pessimistic, based on Eta Regional Climate Model, were simulated considering changes in radiation, air temperature, wind, precipitation and flow. The results indicate changes in the thermal profiles regime, with increasing occurrence of mixing events and variations on the stratification patterns.
Stream and Session
false