DOI: 10.5194/tc-14-1067-2020
论文题名: Ice island thinning: Rates and model calibration with in situ observations from Baffin Bay, Nunavut
作者: Crawford A.J. ; Mueller D. ; Crocker G. ; Mingo L. ; Desjardins L. ; Dumont D. ; Babin M.
刊名: Cryosphere
ISSN: 19940416
出版年: 2020
卷: 14, 期: 3 起始页码: 1067
结束页码: 1081
语种: 英语
英文摘要: A 130 km2 tabular iceberg calved from Petermann Glacier in northwestern Greenland on 5 August 2012. Subsequent fracturing generated many individual large ice islands , including Petermann ice island (PII)-A-1-f, which drifted between Nares Strait and the North Atlantic. Thinning caused by basal and surface ablation increases the likelihood that these ice islands will fracture and disperse further, thereby increasing the risk to marine transport and infrastructure as well as affecting the distribution of freshwater from the polar ice sheets. We use a unique stationary and mobile ice-penetrating radar dataset collected over four campaigns to PII-A-1-f to quantify and contextualize ice island surface and basal ablation rates and calibrate a forced convection basal ablation model. The ice island thinned by 4.7m over 11 months. The majority of thinning (73 %) resulted from basal ablation, but the volume loss associated with basal ablation was 12 times less than that caused by areal reduction (e.g. wave erosion, calving, and fracture). However, localized thinning may have influenced a large fracture event that occurred along a section of ice that was 40m thinner than the remainder of the ice island. The calibration of the basal ablation model, the first known to be conducted with field data, supports assigning the theoretically derived value of 1:210-5 m2=5 s-1=5C-1 to the model s bulk heat transfer coefficient with the use of an empirically estimated ice ocean interface temperature. Overall, this work highlights the value of systematically collecting ice island field data for analyzing deterioration processes, assessing their connections to ice island morphology, and adequately developing models for operational and research purposes. © 2020 Copernicus GmbH. All rights reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/164435
Appears in Collections: 气候变化与战略
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作者单位: Department of Geography and Environmental Studies, Carleton University, Ottawa, ON K1S 5B6, Canada; School of Geography and Sustainable Development, University of St Andrews, St Andrews, KY16 9AJ, United Kingdom; Blue System Integration Ltd., Vancouver, BC V5W 3H4, Canada; Institut des Sciences de la Mer de Rimouski, Université du Québec À Rimouski, Rimouski, QC G5L 3A1, Canada; Département de Biologie, Université Laval, Québec, QC G1V 0A6, Canada
Recommended Citation:
Crawford A.J.,Mueller D.,Crocker G.,et al. Ice island thinning: Rates and model calibration with in situ observations from Baffin Bay, Nunavut[J]. Cryosphere,2020-01-01,14(3)