Linking Glacier Discharge and Ocean Circulation at the Edge of a Tidewater Glacier Using New Measurement Techniques
Improved predictions of future mass loss from Greenland are essential to resolving issues of global concern, such as sea-level rise and the freshening of the North Atlantic. Such predictions are hampered by a poor understanding of processes occurring at the face of glaciers that terminate in the marine waters of fjords. Data collection in such locales is difficult and dangerous, because the glaciers are intermittently calving icebergs. Using other funding, the scientists involved in this project have collected two unique data sets from near a glacier face in Greenland and propose to analyze these data. A successful and insightful project will transform the manner in which we model and observe these regions. This project brings together an interdisciplinary team of oceanographers, glaciologists and engineers, including a graduate student and a post-doctoral associate who will benefit from exposure to the diverse methods to be used in this interdisciplinary science project. A multimedia Ice Sheet / Ocean Interaction exhibit at the MIT Museum to run for the duration of this project, along with two public museum lectures by project personnel, will provide dedicated and widely accessible public dissemination of the research methodology and science. This work will provide a detailed description of the dynamics within the ice/ocean boundary layer of a medium-sized glacier in west Greenland, whose margins are characterized by turbulent plumes fed by subglacial discharge, as well as more quiescent regions. The data, collected over two summer seasons (one with exceptional melt) using private funds, include unique measurements within 100 m of the ice front taken from two autonomous vehicles (one surface and one underwater) and moorings deployed by helicopter. Ocean property and velocity data will be used to characterize the spatial and temporal variability of the near-ice dynamics and will be compared with existing theories. This analysis will be complemented by glaciological, meteorological and climate model data to constrain the frontal position, catchment size, glacier velocity, surface meltwater production and runoff. A key objective is to characterize the parameter regime in order to constrain future modeling. A second objective is to evaluate and provide feedback on the use of new technology to overcome the challenges of observations in this region, a requirement for future oceanographic and glaciological investigations.