气候变化领域集成服务门户(CCPortal): A protocol for calculating basal melt rates in the ISMIP6 Antarctic ice sheet projections

CCPortal

DOI	10.5194/tc-14-3111-2020
	A protocol for calculating basal melt rates in the ISMIP6 Antarctic ice sheet projections
	Jourdain N.C.; Asay-Davis X.; Hattermann T.; Straneo F.; Seroussi H.; Little C.M.; Nowicki S.
发表日期	2020
ISSN	19940416
起始页码	3111
结束页码	3134
卷号	14 期号:9
英文摘要	Climate model projections have previously been used to compute ice shelf basal melt rates in ice sheet models, but the strategies employed-e.g., ocean input, parameterization, calibration technique, and corrections-have varied widely and are often ad hoc. Here, a methodology is proposed for the calculation of circum-Antarctic basal melt rates for floating ice, based on climate models, that is suitable for ISMIP6, the Ice Sheet Model Intercomparison Project for CMIP6 (6th Coupled Model Intercomparison Project). The past and future evolution of ocean temperature and salinity is derived from a climate model by estimating anomalies with respect to the modern day, which are added to a present-day climatology constructed from existing observational datasets. Temperature and salinity are extrapolated to any position potentially occupied by a simulated ice shelf. A simple formulation is proposed for a basal melt parameterization in ISMIP6, constrained by the observed temperature climatology, with a quadratic dependency on either the nonlocal or local thermal forcing. Two calibration methods are proposed: (1) based on the mean Antarctic melt rate (MeanAnt) and (2) based on melt rates near Pine Island's deep grounding line (PIGL). Future Antarctic mean melt rates are an order of magnitude greater in PIGL than in MeanAnt. The PIGL calibration and the local parameterization result in more realistic melt rates near grounding lines. PIGL is also more consistent with observations of interannual melt rate variability underneath Pine Island and Dotson ice shelves. This work stresses the need for more physics and less calibration in the parameterizations and for more observations of hydrographic properties and melt rates at interannual and decadal timescales. © 2020 Copernicus GmbH. All rights reserved.
英文关键词	annual variation; calibration; climate modeling; climatology; CMIP; grounding line; ice sheet; ice shelf; parameterization; timescale; Florida [United States]; Pine Island; United States
语种	英语
来源期刊	Cryosphere
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/202119
作者单位	Univ. Grenoble Alpes/CNRS/IRD/G-INP, Ige, Grenoble, France; Los Alamos National Laboratory, Los Alamos, NM, United States; Helmholtz Centre for Polar and Marine Research, Alfred Wegener Institute, Bremerhaven, Germany; Research Department, Section for Oceans and Sea Ice, Norwegian Polar Institute, Tromsø, Norway; Scripps Institution of Oceanography, University of California San Diego, San diego, CA, United States; Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, United States; Atmospheric and Environmental Research Inc., Lexington, MA, United States; Cryospheric Sciences Branch, Nasa Gsfc, Greenbelt, MD, United States; Department of Geology, University at Buffalo, Buffalo, NY, United States; Research and Education in ENergy, Environment and Water (RENEW) Institute, University at Buffalo, Buffalo, NY, United States
推荐引用方式 GB/T 7714	Jourdain N.C.,Asay-Davis X.,Hattermann T.,et al. A protocol for calculating basal melt rates in the ISMIP6 Antarctic ice sheet projections[J],2020,14(9).
APA	Jourdain N.C..,Asay-Davis X..,Hattermann T..,Straneo F..,Seroussi H..,...&Nowicki S..(2020).A protocol for calculating basal melt rates in the ISMIP6 Antarctic ice sheet projections.Cryosphere,14(9).
MLA	Jourdain N.C.,et al."A protocol for calculating basal melt rates in the ISMIP6 Antarctic ice sheet projections".Cryosphere 14.9(2020).