The NASA Mass Change Designated Observable Study Team

The 2017-2027 US National Academy of Sciences Decadal Survey for Earth Science and Applications from Space classified mass change as one of five designated observables having the highest priority in terms of Earth observations required to better understand the Earth system over the next decade.  In response to this designation, NASA initiated multi-center studies with an overarching goal of defining observing system architectures for each designated observable.  Here, we discuss the progress made and future plans for the Mass Change Designated Observable study. Progress includes the development of a Science and Applications Traceability Matrix (SATM), the definition of three different architectural classes that have potential to be responsive to the designated science objectives, and a framework to quantitatively link the performance of specific architectures to the SATM.  We will describe a Value Framework that has been developed to assess the value of each architecture in terms of science return, cost, schedule, and technical maturity.  Results assessing the value of 50+ architecture variants will be shown and discussed. Finally, the current status of the study process, and future plans will be discussed.