A Plastic Network Approach to Model Calving Glacier Advance and Retreat

Frontiers in Digital Humanities

Bassis, Jeremy N.¹  Ultee, Lizz¹ 

[1] Department of Climate and Space, University of Michigan, Ann Arbor, MI, USA

关键词: plastic approximation;    Flowline;    network;    tidewater glacier dynamics;    Jakobshavn Isbræ;    Helheim Glacier;    Columbia Glacier;    Hubbard Glacier;   

DOI  :  10.3389/feart.2017.00024

学科分类：社会科学、人文和艺术（综合）

来源: Frontiers

【 摘 要 】

Calving glaciers contribute substantially to sea level rise, but they are challenging to represent in models. Fine resolution is required for continental-scale models to accurately resolve calving dynamics and in many cases glacier geometry is too complicated to be adequately reflected by more simplified models. Flowline models are able to resolve flow along the main branch of a glacier, but many of those in current use either ignore tributaries entirely or parameterize their effect using a measure of “equivalent width”. Here we present a simple method to simulate terminus advance and retreat for an interacting network of glacier branches, based on a model extending Nye’s 1953 perfect plastic flow approximation to calving glaciers. We apply the method to case studies of four marine-terminating glaciers: Jakobshavn Isbræ and Helheim Glacier of Greenland, and Columbia and Hubbard Glaciers of Alaska. Given bed topography and upstream elevation history, our method reproduces observed patterns of terminus advance and retreat in all cases, as well as centerline profiles for all branches.

【 授权许可】

CC BY