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  • Antarctic surface climate and surface mass balance in the Community Earth System Model version 2 during the satellite era and into the future (1979–2100)
Title: Antarctic surface climate and surface mass balance in the Community Earth System Model version 2 during the satellite era and into the future (1979–2100)
Abstract. Earth system models (ESMs) allow us to explore minimally observed components of the Antarctic Ice Sheet (AIS) climate system, both historically andunder future climate change scenarios. Here, we present and analyze surface climate output from the most recent version of the National Center forAtmospheric Research's ESM: the Community Earth System Model version 2 (CESM2). We compare AIS surface climate and surface mass balance (SMB) trendsas simulated by CESM2 with reanalysis and regional climate models and observations. We find that CESM2 substantially better represents the mean-state AIS near-surface temperature, wind speed, and surface melt compared with its predecessor, CESM1. This improvement likely results from theinclusion of new cloud microphysical parameterizations and changes made to the snow model component. However, we also find that grounded CESM2 SMB(2269 ± 100 Gt yr−1) is significantly higher than all other products used in this study and that both temperature andprecipitation are increasing across the AIS during the historical period, a trend that cannot be reconciled with observations. This study provides acomprehensive analysis of the strengths and weaknesses of the representation of AIS surface climate in CESM2, work that will be especially useful inpreparation for CESM3 which plans to incorporate a coupled ice sheet model that interacts with the ocean and atmosphere.  more » « less
Award ID(s):
1952199
PAR ID:
10542323
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
The Cryosphere/ EGU
Date Published:
Journal Name:
The Cryosphere
Volume:
16
Issue:
10
ISSN:
1994-0424
Page Range / eLocation ID:
4163 to 4184
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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