Principal Investigator (PI): Eric Rignot, University of California, Irvine
Ice sheets hold the largest potential for sea level rise in the coming decades to centuries and represent the largest source of uncertainty in projected sea level rise (IPCC AR4, 2007; Willis and Church, 2012). At present, the ice sheets in Greenland and Antarctica are already contributing significantly to sea level change (Rignot et al., 2011). Ice sheet surface velocity is a fundamental observable of their dynamics, that has only been available recently from space and that is central to assessments of past, current and future contributions to sea level (US Climate Change Research Program [USCCRP], 2012).
Here, we will generate and distribute continental-scale, multi-year, digital ice velocity vector products of the Antarctic continent as Earth System Data Records (ESDRs) to the research community. We have developed experience in a prior Making Earth System Data Records for Use in Research Environments (MEaSUREs) project, "Ice Velocity Mapping of the Great Ice Sheets: Antarctica" (PI: Eric Rignot) to generate these ESDRs, overcome major technical and scientific hurdles, quantify errors for the first time, and distribute the ESDRs to the broad research community (Rignot et al., 2011a).
The new ESDRs and ancillary products such as grounding line positions and image mosaics from NASA’s Moderate Resolution Imaging Spectroradiometer (MODIS) and international Interferometric Synthetic-Aperture Radar (InSAR) will help document the rate of change in ice sheet dynamics and boundaries, the rates of ice mass flow to the ocean and contribution to sea level rise, and the sensitivity of ice dynamics to climate forcing on multi-decadal time scales for the first time.
These ESDRs will in turn play a central role in the development of more realistic numerical ice sheet models coupled with atmospheric and oceanic numerical models to produce more reliable hindcasts and forecasts of ice sheet evolution. Data required for this project will be provided by a suite of satellites operated by international agencies that cooperated with NASA in a highly successful pole-to-cost InSAR coverage of Antarctica for the International Polar Year (IPY) 2008-2009 that is unique in the history of remote sensing and collaboration between space agencies. These agencies have expressed the desire to continue this collaboration beyond the 2008-2009 International Polar Year.
The project will therefore employ data from the Canadian Space Agency RADARSAT-2, the Japanese Aerospace Exploration Agency Advanced Land Observing Satellite "DAICHI" (ALOS) Phased Array type L-band Synthetic Aperture Radar 2 (PALSAR-2), the European Space Agency Sentinel-1, as well as historical data from RADARSAT-1, ALOS PALSAR, Environmental Satellite (Envisat) Advanced Synthetic Aperture Radar (ASAR) and European Remote Sensing satellites 1 and 2 (ERS-1, ERS-2) going back to 1996. The project will also provide a pathway for NASA’s Deformation, Ecosystem Structure and Dynamics of Ice (DESDynI-R) mission to be flown around 2017. The ESDRs will be generated using well-proven, documented and peer-reviewed algorithms and numerical tools developed over the past twenty years that represent the state of the art in mapping ice sheet velocity from space, independent of cloud cover and solar illumination, at a uniform, high-resolution sampling of entire continent.
For data distribution, customer support and feedback, we will continue to partner with NASA's National Snow and Ice Data Center Distributed Active Archive Center (NSIDC DAAC), in Boulder, CO, a national data depository for cryospheric science products, with international reputation and unmatched experience archiving, documenting and distributing cryospheric data and querying its scientific impact on the research community, educational entities and the public at large. Glaciologists, ice sheet modelers, climate scientists, geophysicists, physical oceanographers, solid earth scientists, atmospheric scientists, biologists and geologists, scientist interested in the Antarctic continent at large but also educational professional, organizers of field logistics, journalists and the public will use these ESDRs.
These science products will establish a long-term legacy for Antarctic science and the evolution of Polar Regions in a warming climate. The project will serve the highest science objectives of NASA's Earth Science Mission Directorate in climate change research, in particular its science objectives in the study of the Earth's ice cover and sea level rise.