Michael M. Watkins, GRACE Project Scientist, Jet Propulsion Laboratory
The Gravity Recovery and Climate Experiment (Grace) is an innovative climate monitoring mission using repeated global gravity mapping to track large scale mass fluxes on the Earth. Applications range from oceanography to groundwater storage and glaciology. Selected key results that have generated significant scientific and public interest include breakthrough observations of polar ice mass changes in Greenland and Antarctica, groundwater depletion in locations from India and Africa to our backyard in California's Central Valley, and ocean bottom pressure changes in both the Arctic and southern oceans. Due to the spectacular success of this pioneering mission, in the past year NASA has included a GRACE Follow-On mission in the FY11 budget for launch in 2016. This mission is focused on data continuity and high GRACE heritage, but also includes a technical demonstration of a laser interferometer system drawn heavily from LISA development experience at Caltech/JPL, which will pave the way for future gravity mapping missions with improved spatial resolution.
In this talk, we will review the basic challenge of low-low satellite tracking for gravity mapping, the basic GRACE design, and the improvements for GRACE FO, along with the latest science results and rationale for continued measurements for understanding interannual and decadal climate variability. .