Abstract's details
Global Water Monitor: Operational Monitoring of Lakes, Wetlands, and River Reaches for Natural Hazards and Regional Security
CoAuthors
Event: 2022 Ocean Surface Topography Science Team Meeting
Session: Application development for Operations
Presentation type: Type Forum only
Contribution: PDF file
Abstract:
The Global Water Monitor is a NASA funded operational program offering water-related products for lakes, reservoirs, river reaches, and wetland zones. These are being derived from i) the NASA/CNES TOPEX/Jason/Sentinel-6 and ESA/ISRO/CNES ERS/ENVISAT/SARAL/Sentinel-3 series of radar altimeters, ii) the MODIS series of multispectral imagers, and iii) in future, the new ICESat-2/GEDI DEM’s. The products will be a combination of water level, surface extent, water storage, and bathymetry. The main stakeholders are the USDA/Foreign Agricultural Service, various Wetland-related organizations, and USACE/NGA.
There is a demand for a global monitoring service that captures the variations in the smallest (1 to 100 km2) reservoirs and water holdings in arid and semi-arid regions. Here, water resources are critical to both agriculture and regional security. Surface water level products across wetland zones are also being requested in respect of inland fisheries and catch potential, and observations of river reaches in gauge-poor regions are required in lieu of spring melt watches and flood hazards.
In addition to meeting operational requirements, recent efforts to create (up to) 25yr timelines has also shown that great care needs to be taken with respect to the merger of results from multiple instrument platforms. Such accuracy is required for the formation of high-quality Earth Data Records and the creation of Long-Term Status Indicators which inform end users of deviations from normal conditions.
Technical advances e.g., the use of Delay-Doppler SAR and the novel FF-SAR technique, are looking to improve along-track spatial resolution and thus attain much smaller lakes and narrower river reaches. The new Sentinel-6 Michael Freilich mission is allowing continuity of the 10-day resolution water level products but with improved surface acquisition (DIODE/DEM mode) and Range determination via optimum waveform retracking and upgraded wet tropospheric corrections. Sentinel-6 is capturing current elevation status accurately and this will help determine current water and energy resources and longer-term trends that might affect regional economic and political instability.
There is a demand for a global monitoring service that captures the variations in the smallest (1 to 100 km2) reservoirs and water holdings in arid and semi-arid regions. Here, water resources are critical to both agriculture and regional security. Surface water level products across wetland zones are also being requested in respect of inland fisheries and catch potential, and observations of river reaches in gauge-poor regions are required in lieu of spring melt watches and flood hazards.
In addition to meeting operational requirements, recent efforts to create (up to) 25yr timelines has also shown that great care needs to be taken with respect to the merger of results from multiple instrument platforms. Such accuracy is required for the formation of high-quality Earth Data Records and the creation of Long-Term Status Indicators which inform end users of deviations from normal conditions.
Technical advances e.g., the use of Delay-Doppler SAR and the novel FF-SAR technique, are looking to improve along-track spatial resolution and thus attain much smaller lakes and narrower river reaches. The new Sentinel-6 Michael Freilich mission is allowing continuity of the 10-day resolution water level products but with improved surface acquisition (DIODE/DEM mode) and Range determination via optimum waveform retracking and upgraded wet tropospheric corrections. Sentinel-6 is capturing current elevation status accurately and this will help determine current water and energy resources and longer-term trends that might affect regional economic and political instability.