Global Water Monitor: Operational Monitoring of Lakes, Wetlands, and River Reaches for Natural Hazards and Regional Security

Martina Ricko (KBR at NASA/GSFC, United States)


Charon Birkett (NASA/GSFC, USA); Xu Yang (KBR at NASA/GSFC, USA); Curt Reynolds (USDA/FAS, USA); Elias Deeb (ERDC/USACE, USA)

Event: 2020 Ocean Surface Topography Science Team Meeting (virtual)

Session: Application development for Operations

Presentation type: Type Forum only

The Global Water Monitor is a new NASA/USDA funded operational program offering water-related products for lakes, reservoirs, river reaches, and wetland zones. These will be derived from: i) the NASA/CNES TOPEX/Jason and ESA/ISRO/CNES series of radar altimeters, ii) the Landsat/MODIS series of multispectral imagers, and iii) the SRTM, ASTER, and ICESat-2 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 an increasing demand for a global monitoring service that in particular 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. There is also a demand for surface water level products across wetland zones in respect of inland fisheries and assessments of catch potential. Observations of river reaches in gauge-poor regions has also been requested in lieu of spring melts and flood hazards.
In addition to meeting operational requirements, recent efforts to create (up to) 25-yr 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, i.e., the use of Delay-Doppler SAR and the novel FF-SAR technique are looked for improving along-track spatial resolution and thus better detection of the smallest water bodies and narrowest river reaches. The launch of the Sentinel-6 Michael Freilich mission will allow continuity of the 10-day resolution records but with improved surface acquisition (DIODE/DEM mode) and improved Range determination via optimum waveform retracking and upgraded wet tropospheric correction. In addition to archive measurements, the operational monitoring of water bodies must be able to capture current elevation status accurately to help determine water and energy resources, and thus assess trends that might affect regional economic and political instability.
Martina Ricko
United States