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Characteristics of Future Warmer Base States in CESM2

Journal Article · · Earth and Space Science
DOI:https://doi.org/10.1029/2020EA001296· OSTI ID:1664587
 [1];  [2];  [1];  [1];  [3];  [1];  [1];  [1];  [4];  [1];  [1];  [1];  [1];  [1];  [1]
  1. National Center for Atmospheric Research Boulder CO USA
  2. National Center for Atmospheric Research Boulder CO USA, School of Earth, Atmosphere and Environment Monash University Melbourne Victoria Australia
  3. Pacific Northwest National Laboratory Washington DC USA
  4. Department of Atmospheric and Oceanic Sciences and Institute of Arctic and Alpine Research University of Colorado Boulder Boulder CO USA

Abstract

Simulations of 21st century climate with Community Earth System Model version 2 (CESM2) using the standard atmosphere (CAM6), denoted CESM2(CAM6), and the latest generation of the Whole Atmosphere Community Climate Model (WACCM6), denoted CESM2(WACCM6), are presented, and a survey of general results is described. The equilibrium climate sensitivity (ECS) of CESM2(CAM6) is 5.3°C, and CESM2(WACCM6) is 4.8°C, while the transient climate response (TCR) is 2.1°C in CESM2(CAM6) and 2.0°C in CESM2(WACCM6). Thus, these two CESM2 model versions have higher values of ECS than the previous generation of model, the CESM (CAM5) (hereafter CESM1), that had an ECS of 4.1°C, though the CESM2 versions have lower values of TCR compared to the CESM1 with a somewhat higher value of 2.3°C. All model versions produce credible simulations of the time evolution of historical global surface temperature. The higher ECS values for the CESM2 versions are reflected in higher values of global surface temperature increase by 2,100 in CESM2(CAM6) and CESM2(WACCM6) compared to CESM1 between comparable emission scenarios for the high forcing scenario. Future warming among CESM2 model versions and scenarios diverges around 2050. The larger values of TCR and ECS in CESM2(CAM6) compared to CESM1 are manifested by greater warming in the tropics. Associated with a higher climate sensitivity, for CESM2(CAM6) the first instance of an ice‐free Arctic in September occurs for all scenarios and ensemble members in the 2030–2050 time frame, but about a decade later in CESM2(WACCM6), occurring around 2040–2060.

Sponsoring Organization:
USDOE
Grant/Contract Number:
AC02-05CH11231
OSTI ID:
1664587
Alternate ID(s):
OSTI ID: 1785985
OSTI ID: 1786786
Journal Information:
Earth and Space Science, Journal Name: Earth and Space Science Journal Issue: 9 Vol. 7; ISSN 2333-5084
Publisher:
American Geophysical Union (AGU)Copyright Statement
Country of Publication:
United States
Language:
English

References (22)

A new method for diagnosing radiative forcing and climate sensitivity journal January 2004
High Climate Sensitivity in the Community Earth System Model Version 2 (CESM2) journal July 2019
Effects of Model Resolution, Physics, and Coupling on Southern Hemisphere Storm Tracks in CESM1.3 journal November 2019
The Whole Atmosphere Community Climate Model Version 6 (WACCM6) journal December 2019
The Impact of Prescribed Ozone in Climate Projections Run With HadGEM3‐GC3.1 journal November 2019
Arctic Sea Ice in Two Configurations of the CESM2 During the 20th and 21st Centuries journal September 2020
Latest climate models confirm need for urgent mitigation journal December 2019
Sensitivity of climate simulations to the parameterization of cumulus convection in the Canadian climate centre general circulation model journal September 1995
Context for interpreting equilibrium climate sensitivity and transient climate response from the CMIP6 Earth system models journal June 2020
Combinations of Natural and Anthropogenic Forcings in Twentieth-Century Climate journal October 2004
A PDF-Based Model for Boundary Layer Clouds. Part I: Method and Model Description journal December 2002
The Impact of Convection on ENSO: From a Delayed Oscillator to a Series of Events journal November 2008
The Community Earth System Model: A Framework for Collaborative Research journal September 2013
The Community Earth System Model (CESM) Large Ensemble Project: A Community Resource for Studying Climate Change in the Presence of Internal Climate Variability journal August 2015
Influence of Continental Ice Retreat on Future Global Climate journal May 2013
Climate Change Projections in CESM1(CAM5) Compared to CCSM4 journal September 2013
Uncertainty in Climate Change Projections of the Hadley Circulation: The Role of Internal Variability journal September 2013
Advanced Two-Moment Bulk Microphysics for Global Models. Part I: Off-Line Tests and Comparison with Other Schemes journal February 2015
A new parametrization of turbulent orographic form drag
  • Beljaars, Anton C. M.; Brown, Andrew R.; Wood, Nigel
  • Quarterly Journal of the Royal Meteorological Society, Vol. 130, Issue 599 https://doi.org/10.1256/qj.03.73
journal April 2004
The Scenario Model Intercomparison Project (ScenarioMIP) for CMIP6 journal January 2016
The Detection and Attribution Model Intercomparison Project (DAMIP v1.0) contribution to CMIP6 journal January 2016
Description and evaluation of a new four-mode version of the Modal Aerosol Module (MAM4) within version 5.3 of the Community Atmosphere Model journal January 2016

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