This award supports a project to assess Antarctic ice sheet mass balance at both continental and regional spatial scales, using high-accuracy satellite gravity measurements from the NASA Gravity Recovery and Climate Experiment (GRACE) mission. The intellectual merit of the proposed investigation is that this study will provide improved assessments of Antarctic ice mass balance at continental, regional, and catchment basin scales using GRACE gravity data with unprecedented accuracy. The proposed comparison between GRACE estimates and remote sensing measurements are critical for correctly quantifying and interpreting Antarctic ice mass balance at different spatial and temporal scales. The proposing team has a strong record of publications related to geophysical applications of GRACE time-variable gravity data (including a few major papers targeting polar ice sheets and mountain glacial melting that have been recently published), and has demonstrated a thorough understanding of GRACE data and related products; and the team has been working in the forefront in designing optimized filtering methods, and developing numerical forward modeling techniques, which are critical for the study of regional or catchment basin scale ice mass changes using GRACE data. The broader impacts of the proposed activities include that this project will actively involve student participation and training, through the support of the thesis study of a graduate student; and will extensively involve in general education and public outreach (E/PO) activities (the PI is actually leading an E/PO team at the Center for Space Research through a federally funded project), and the results from this investigation will help to inspire the interest of future geoscientists and promote the public awareness of the significant impacts on our living environment from the rapidly changing climate (e.g., global warming, ice sheet melting, and sea level rise) of our home planet system. Finally, the proposed investigation addresses one of the emphasis areas of the IPY program (i.e. Ice Sheet History and Dynamics: How has the volume and geographic extent of polar ice sheets varied through time?). Quantifying ice mass changes over the Antarctic ice sheet is of great importance in understanding climate changes of our planet system.
