Ross Powell

I wish to host a NOAA Visiting Scientist to work with me and a collaborative research team to investigate ice-ocean interaction in an Antarctic sub-ice-shelf cavity using custom-designed oceanographic instrumentation. I am currently a lead co-PI on two NOAA grants to Northern Illinois University for funding equipment and instrumentation to study environmental and climatic change. As part of those grants we are constructing two specialized instruments to collect important data for helping constrain the future behavior of the Antarctic Ice Sheet. The first is a Sub-Ice ROV (remotely operated vehicle) (SIR) being constructed by Deep Ocean Engineering and Research (DOER) in California, and which is nearly completed. The other instrumentation is a Geochemical Instrumentation Package for Sub-Ice Exploration (GIPSIE), which we are currently preparing to construct, with most of its components having been purchased. As part of this request the Visiting Scientist would work with DOER to construct GIPSIE and finalize its integration for deployment with SIR. We have gathered a team of 15 PIs from 9 institutions with diverse expertise for conducting the science using these instruments. We have three pending proposals submitted to NSF that describe an âœintegrated systems approach to analyze physical, chemical, and geobiological interactions in subglacial environments poised at the interface of the Antarctic cryosphere, geosphere and global ocean. One of the proposals for which I am lead-PI, concentrates on stability of ice stream grounding-zones that may be perturbed by internal ice stream dynamics, filling/draining cycles of subglacial lakes, and/or increased thermal ocean forcing by warming ocean water masses. Grounding-zones, where the ice sheet becomes afloat in the sea, are seen as high priority targets to investigate due to their unknown contributions to ice sheet stability under future global warming scenarios. The latest IPCC report recognized that the greatest uncertainties in assessing future global sea-level change stem from a poor understanding of ice sheet dynamics and ice sheet vulnerability to oceanic and atmospheric warming. Disintegration of the West Antarctic Ice Sheet alone would contribute 3-5m to global sea-level rise, making WAIS a focus of scientific concern due to its potential susceptibility to internal or ocean-driven instability.