Development of an Air-droppable Goedetic-seismic Ice Penetrator for Response Studies of Antarctic Ice Shelves and Icebergs to Ocean Forcings

Massachusetts Institute Of Technology, Cambridge MA

Investigators

Abstract

Title: Development of an air-droppable geodetic-seismic ice penetrator for response studies of Antarctic ice shelves and icebergs to ocean forcings Non-technical abstract: The stability of the entire Antarctic glacial system depends critically on the stability of its ice shelves. Antarctic ice shelves, the ocean-floating margins of the massive Antarctic ice sheet, are showing signs of rapid decline. Ice shelf decay leads to increased discharge of grounded-ice to the ocean, and to mean sea-level rise. Ice shelf disintegration would drive the continental Antarctic ice sheet, in particular the West Antarctica section, to eventual collapse. Ocean waves may provide the tipping force necessary to trigger the failure of a thinned, mechanically weakened ice shelf. Monitoring how the ice shelves are responding to changing oceanic and atmospheric conditions is critically needed, but obtaining such measurements is technologically and logistically challenging. This award supports the development of novel technologies that can meet the challenge. Technical abstract: The project aims to address the observational gap that exists in Antarctic ice-shelf glaciology for timescales shorter than the few-day ice-fields provided by satellite geodesy and imagery. Through these efforts, a new scientific instrument will be devised and prototyped that closes the gap into the high-frequency (from monthly to sub-seconds) domain where ice shelves respond dynamically to oceanic forcings. This will be accomplished by integrating state-of-the-art GPS and seismometer sensors into a single broadband scientific instrument with data download capabilities in near-real time. This scientific device will be packaged into an ice penetrator that can be air-dropped onto an ice shelf (and tabular icebergs) from a helicopter. The technology readiness of this geodetic-seismic ice penetrator (GSIP) will be assessed based on verification of performance of a functional prototype through both laboratory and field trials. Having continuous, high-resolution GSIP observations of Antarctic ice shelves would provide meaningful constraints to Antarctic ice-shelf decay models, and contribute to an improved understanding of ice-ocean dynamic interactions. GSIPs would greatly simplify logistic challenges by expediting deployment, reduce the on-ice footprint in Antarctica, enhance current capabilities for in situ glaciological observations, and benefit the broader polar community.