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Title: The role of regional feedbacks in glacial inception on Baffin Island: the interaction of ice flow and meteorology
Abstract. Over the past 0.8 million years, 100kyr ice ages have dominatedEarth's climate with geological evidence suggesting the last glacialinception began in the mountains of Baffin Island. Currently,state-of-the-art global climate models (GCMs) have difficulty simulatingglacial inception, possibly due in part to their coarse horizontal resolutionand the neglect of ice flow dynamics in some models. We attempt to addressthe role of regional feedbacks in the initial inception problem on BaffinIsland by asynchronously coupling the Weather Research and Forecast (WRF) model,configured as a high-resolution inner domain over Baffin and an outerdomain incorporating much of North America, to an ice flow model using theshallow ice approximation. The mass balance is calculated from WRFsimulations and used to drive the ice model, which updates the ice extentand elevation, that then serve as inputs to the next WRF run. We drive theregional WRF configuration using atmospheric boundary conditions from 1986that correspond to a relatively cold summer, and with 115kya insolation.Initially, ice accumulates on mountain glaciers, driving downslope ice flowwhich expands the size of the ice caps. However, continued iterations of theatmosphere and ice models reveal a stagnation of the ice sheet on BaffinIsland, driven by melting due to warmer temperatures at the margins of theice caps. This warming is caused by changes in the regional circulation thatare forced by elevation changes due to the ice growth. A stabilizing feedbackbetween ice elevation and atmospheric circulation thus prevents fullinception from occurring.  more » « less
Award ID(s):
1740533
PAR ID:
10110251
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Climate of the Past
Volume:
14
Issue:
10
ISSN:
1814-9332
Page Range / eLocation ID:
1441 to 1462
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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