Meeting
2016 SIPN Workshop
Presentation Type
plenary
Presentation Theme
Process Studies
Abstract Authors

Robert Newton, Lamont-Doherty Earth Observatory, bnewton [at] ldeo.columbia.edu
Stephanie Pfirman, Barnard College, spfirman [at] barnard.edu
Bruno Tremblay, McGill University, bruno.tremblay [at] mcgill.ca
Patricia Derepentigny, McGill University, patricia.derepentigny [at] mail.mcgill.ca

Abstract

We apply a Lagrangian sea ice tracking software to the problem of transport between the exclusive economic zones (EEZs) of the coastal Arctic nations over about 3 decades: 1979-2011. Lagrangian tracking is combined with sea ice concentration maps to distinguish sea ice formation and melt events from ice drift. We describe trends in formation and melt locations and sea-ice transport pathways. Most ice, ca. 60%, melts within 100 km of where it is formed; only ca. 15% escapes from its "native" EEZ. Of the ice that does leave its region of formation, the majority is ultimately exported from the Arctic through Fram Strait, melting in the East Greenland Current. While only a small fraction of sea ice is exported from one nation’s exclusive economic zone to another’s, this transport nonetheless amounts to tens of thousands of square kilometers of sea ice. Over the last three decades, as the ice has thinned, ice travelling between nations has accelerated by about 18% per decade. As a result, the transit times between different shelf seas of the Arctic have declined significantly. The total area of sea ice transported between EEZs has increased, with the rate of increase varying regionally. The rapid thinning (approximately 50% over the satellite era) of ice, however, means that the volume of freshwater transport between EEZs in solid form has probably nonetheless declined. As the summer melt expands, melt competes with transport and even fast-moving ice can be “caught” by the melt front before it can “escape” from its EEZ. We apply our tracking method to climate model output to consider this and other trends will evolve as the Arctic transitions to a seasonally ice-free state.

Time
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