Arctic Ocean Sea Ice and Ocean Circulation Changes Using a Novel High-Precision GPS Autonomous Platform

IPY2012 Conference Montréal. From Knowledge to Action, 22-27 April 2012, Montréal, CanadaThe marine environment of the Arctic Ocean is under profound transformation, as clearly shown by observations and model predictions across a range of disciplines. The rapid decline in sea ice extent and volume during the boreal summers is a prime example. To improve our understanding of the key physical processes that drive change in this region, it is crucial to monitor the complex ocean-cryosphere-atmosphere system. This presentation explores how sea ice is changing in this region by using a combined observational and modeling approach that builds heavily on the latest technological advances in Space Geodesy. We have developed a high-precision (i.e., few cm position accuracy), GPS-based autonomous platform suited to the challenging Arctic Ocean environment that enables determination of sea ice motions in three-dimensions with hightemporal sampling and, when deployed as a network, also high-spatial density. The platform includes a sea ice freeboard sensor and two-way communications, thus also enabling near-real time monitoring and remote data retrieval. We have deployed several prototypes of such platform for limited durations both in the Arctic Ocean and the Southern Ocean since 2009, and two full-blown, long-term systems, on the Chukchi Sea, during the boreal summer of 2011. Although monitoring of sea ice motions in this fast changing region goes back to the early days of satellite observations, these systems bring out a level of spatio-temporal detail that has never been seen before, which in turn allows us to question our present understanding of sea ice dynamics. We will describe the technology behind this novel platform, which could also be adapted to other applications that require sustained operations and observations in the Arctic environment, and present results pertaining to sea ice dynamics, Arctic Ocean tides, ocean dynamic topography, ocean currents, and sea ice freeboard, thickness, and mass balance, from the analysis of the GPS and freeboard data collected by those systemsPeer Reviewe