Assessing the capabilities of the Surface Water and Ocean Topography (SWOT) mission for large lake water surface elevation monitoring under different wind conditions

Lakes are important sources of freshwater and provide essential ecosystem services. Monitoring their spatial and temporal variability, and their functions, is an important task within the development of sustainable water management strategies. The Surface Water and Ocean Topography (SWOT) mission will provide continuous information on the dynamics of continental (rivers, lakes, wetlands and reservoirs) and ocean water bodies. This work aims to contribute to the international effort evaluating the SWOT satellite (2022 launch) performance for water balance assessment over large lakes (e.g., >100 km2). For this purpose, a hydrodynamic model was set up over Mamawi Lake, Canada, and different wind scenarios on lake hydrodynamics were simulated. The derived water surface elevations (WSEs) were compared to synthetic elevations produced by the Jet Propulsion Laboratory (JPL) SWOT high resolution (SWOT-HR) simulator. Moreover, water storages and net flows were retrieved from different possible SWOT orbital configurations and synthetic gauge measurements. In general, a good agreement was found between the WSE simulated from the model and those mimicked by the SWOT-HR simulator. Depending on the wind scenario, errors ranged between approximately −2 and 5 cm for mean error and from 30 to 70 cm root mean square error. Low spatial coverage of the lake was found to generate important biases in the retrievals of water volume or net flow between two satellite passes in the presence of local heterogeneities in WSE. However, the precision of retrievals was found to increase as spatial coverage increases, becoming more reliable than the retrievals from three synthetic gauges when spatial coverage approaches 100 %, demonstrating the capabilities of the future SWOT mission in monitoring dynamic WSE for large lakes across Canada.

Assessing the capabilities of the SWOT mission for large lake water surface elevation monitoring under different wind conditions

Lakes are important sources of freshwater and provide essential ecosystem services. Monitoring their spatial and temporal variability, as well as of their functions, is an important task within the development of sustainable water management strategies. The Surface Water and Ocean Topography (SWOT) mission will provide continuous information on the dynamics of continental (rivers, lakes, wetlands and reservoirs) and ocean water bodies. This work aims to contribute to the international effort evaluating the SWOT satellite (2022 launch) performance for water balance assessment over large lakes (e.g., > 100 km2). For this purpose, a hydrodynamic model was set up over Mamawi Lake, Canada, and different wind scenarios on lake hydrodynamics were simulated. The derived water surface elevations (WSE) were compared to synthetic elevations produced by the Jet Propulsion Laboratory (JPL) SWOT high resolution (SWOT-HR) simulator. Moreover, water storages and net flows were retrieved from different possible SWOT orbital configurations, as well as synthetic gauge measurements. In general, a good agreement was found between the WSE simulated from the model and those mimicked by the SWOT-HR simulator. Depending on the wind scenario, errors ranged between approximately −2 and 5 cm for mean error, and 30 to 70 cm root mean square error. Low spatial coverage of the lake was found to generate important biases in the retrievals of water volume or net flow between two satellite passes in the presence of local heterogeneities in WSE. However, the precision of retrievals was found to increase as spatial coverage increases, becoming more reliable than the retrievals from 3 synthetic gauges when spatial coverage approaches 100 %, demonstrating the capabilities of the future SWOT mission in monitoring dynamic WSE for large lakes across Canada.

Impacts of Industrial Fresh Water Withdrawals on Calcaiseu Lake Hydrodynamics and Salinity Concentration

In the authors’ previous study, vegetation information was utilized into a hydrodynamic model to predict the flooding coverage and damage to the wetlands in a major water system in southwest Louisiana, the Calcasieu Lake water system. In this study, the target area is extended, ranging from the city of Lake Charles as the north end to the Gulf of Mexico as the south end, including Lake Charles, Calcasieu Lake, Prien Lake, Gulf Intracoastal Waterway (GIWW) and the entire Calcasieu Ship Channel. Measured vegetation data is utilized in the vegetated areas and appropriate friction values are assigned to different types of non-vegetated areas. Salinity is important to aquatic life. It can impact agricultural production, water quality and streams, biodiversity and infrastructure. In this study, both hydrodynamic and salinity transport simulations are conducted. Measurement data from NOAA and USGS are used as boundary conditions. Simulation results were compared with NOAA and USGS data in several other locations. Lake Charles is one of the largest petrochemical industry centers in the country. Numerous plants use tremendous amount of fresh surface water in the area. Recent expansions of several companies increase the fresh water withdraws from the system significantly. One of the purposes of the study is to investigate the effects of increased water withdraw on the hydrodynamics and salinity in the system. The industrial water withdrawals could be from the Calcasieu River in the north of Lake Charles, which is the north boundary of the simulation domain. Cases of different reduced flow rates at Lake Charles were tested, and the effects on hydrodynamics and salinity concentrations and distributions were analyzed. The results can be used as a guideline for industrial and city development in the areas.

The OSL chronology of eolian sand deposition in a perched dune field along the northwestern shore of Lower Michigan

Extensive coastal dunes occur in the Great Lakes region of North America, including northwestern Michigan where some are perched on high (~ 100 m) bluffs. This study focuses on such a system at Arcadia Dunes and is the first to systematically generate optical ages from stratigraphic sections containing buried soils. Dune growth began ca. 4.5 ka during the Nipissing high lake stand and continued episodically thereafter, with periods of increased sand supply at ca. 3.5 ka and ca. 1.7 ka. The most volumetrically dominant phase of dune growth began ca. 1.0 ka and continued intermittently for about 500 years. It may have begun due to the combined effects of a high lake phase, potential changes in lake hydrodynamics with final isostatic separation of Lake Superior from Lakes Michigan and Huron, and increased drought and hydrologic variability associated with the Medieval Warm Period. Thus, this latest eolian phase likely reflects multiple processes associated with Great Lakes water level and climate variability that may also explain older eolian depositional events. Comparison of Arcadia ages and calendar corrected 14C ages from previous studies indicate broad chronological agreement between events at all sites, although it appears that dune growth began later at Arcadia.