The Global Water Monitor: A New Phase in the Operational Monitoring of Lakes, Wetlands, and River Reaches for Resources Management and Hazard Observation

Abstract:

The Global Water Monitor is a new NASA funded operational program offering surface water-related products for lakes, reservoirs, river reaches, and wetland zones. These products are derived from satellite altimetry and multispectral imaging sources such as the NASA/CNES/ESA Jason/Sentinel series and the USGS/NASA Landsat/MODIS series. The primary products are surface water level and surface extent, with secondary bathymetry and water storage products. The primary stakeholders are the US Department of Agriculture/Foreign Agricultural Service, the US Geological Survey, the US Army Corp of Engineers, the US National Geospatial Intelligence Agency, and several international groups and organizations that have priorities focussed on wetland regions.

There is an increasing demand for a global monitoring service considering the sensitivity of ground-based data and the remote accessibility of many basins. For example, stakeholders are requesting the capture of the variations in existing and newly completed reservoirs which supply hydroelectric power, and observation of the smaller lakes and water holdings in arid and semi-arid regions where water resources are critical to agriculture/irrigation supply. There is also a demand for surface water products across wetland zones in respect of inland fisheries and assessments of catch potential for regional markets. Observations of river reaches in gauge-poor regions has also been requested to monitor spring melts and assess flood hazards.

In addition to meeting operational requirements, project efforts aim to provide an historical timeline of observations essentially creating high quality, multi-decadal, Earth Data Records. For lakes and reservoirs, stakeholders also require a set of Status Indicators (SI) that reveal normal or anomalous water storage conditions, and these are defined by a range of short- and long-term datums. These new SI will highlight long-term drought or recharge status, and thus help stakeholders determine whether marked deviations might affect water and power resources and thus regional security.