Enhancement of Elevation and Status Products for Operational Continental Water Monitoring

Author:

Charon Birkett - (NASA Goddard Space Flight Center)

Co-Investigator(s):

Alejandro Egido (Global Science & Technology, Inc.)
Martina Ricko (SGT, Inc.)

Collaborator(s):

Curt Reynolds (USDA Foreign Agricultural Service (FAS))
Denis Blumstein (CNES)
Jack Eggleston (USGS)
Scott Luthcke (NASA Goddard Space Flight Center)
Sophie Le Gac (CNES)

Abstract:

Satellite-based altimetric elevations are a valuable source of continental surface water information and are particularly relevant to inaccessible or restricted data-access regions. The lake, river and wetland data are being utilized in several operational-based programs, the elevations being utilized directly or as a proxy (for precipitation), and they are a contributing parameter in the determination of storage and discharge. Such stakeholder programs focus on water resources (for agriculture, fisheries, energy production, municipal and industry), conservation, or hazards. A continuity of missions allows for historical perspectives in terms of climate variation, trends, and long-term drought recovery, while multiple synergistic datasets allow for cross-validation and a greater spatial coverage. The availability of near real time data is demanded from all end users to assist decision support systems in assessing regional situations and enable a fast response.

This project consists of technical investigations that will assist the development of elevation and associated status warning products for the Global Water Monitor and Global Reservoir and Lake Monitor operational programs that primarily serve the USDA, USGS and NGA. These programs receive NASA/ Applied Sciences support for product creation and integration, but detailed technical evaluation of a new satellite data set, and overall elevation refinement investigations are outside of the Applied Sciences scope.

The investigations will focus on exploring and enhancing surface acquisition and elevation accuracy, with particular emphasis on checking the continuity and validity of the Sentinel-6/Michael Freilich mission data from both the cal/val and science phases. Methodologies will employ standard repeat track techniques, DEM/vector analysis, waveform retracking algorithm output, and the latest Fully-Focussed SAR (FF-SAR) approaches. The team will collaborate with NASA, NOAA, and CNES OST team members, with fast reporting to the OST during the cal/val phase.

Specifically the team will,

a) investigate Sentinel-6/Michael Freilich elevation data acquisition and accuracy to ensure continuity of success with Jason-3,

b) assist with the global refinement of the on-board Jason-3/Seninel-6 DEM for improved surface acquisitions,

c) analyze retracking and FF-SAR algorithm output for improvements in accuracy and spatial resolution respectively,

d) explore the instrument and model based wet tropospheric range corrections in terms of accuracy, target size, consistency, and winter (ice-on) application,

e) examine the accuracy of the operational datasets (24hrs) in comparison to the interim (2-3days) data, and

f) summarize how technical advances can be translated to the operational programs and how they can improve lake and river water elevation warning skills for hazard (flood/drought) application.

Supported by NASA