Identification

Title

Datasets used in Bacmeister et al, JAMES (2020). " CO2 increase experiments ..."

Alternative title(s)

d583117

Abstract

Datasets used in the creation of original figures of Bacmeister et al. JAMES (2020). CO2 increase experiments using the Community Earth System Model (CESM): Relationship to climate sensitivity and comparison of CESM1 to CESM2. We examine the response of the Community Earth System Model versions 1 and 2 (CESM1 and CESM2) to abrupt quadrupling of atmospheric CO2 concentrations (4xCO2) and to 1% annually increasing CO2 concentrations (1% CO2). Different estimates of equilibrium climate sensitivity (ECS) for CESM1 and CESM2 are presented. All estimates show that the sensitivity of CESM2 has increased by 1.5K or more over that of CESM1. At the same time the transient climate response (TCR) of CESM1 and CESM2 derived from 1% CO2 experiments has not changed significantly - 2.1K in CESM1 and 2.0K in CESM2. Increased initial forcing as well as stronger shortwave radiation feedbacks are responsible for the increase in ECS seen in CESM2. A decomposition of regional radiation feedbacks and their contribution to global feedbacks shows that the Southern Ocean plays a key role in the overall behavior of 4xCO2 experiments, accounting for about 50% of the total shortwave feedback in both CESM1 and CESM2. The Southern Ocean is also responsible for around half of the increase in shortwave feedback between CESM1 and CESM2, with a comparable contribution arising over tropical ocean. Experiments using a thermodynamic slab-ocean model (SOM) yield estimates of ECS that are in remarkable agreement with those from fully-coupled earth system model (ESM) experiments for the same level of CO2 increase. Finally, we show that the similarity of TCR in CESM1 and CESM2 masks significant regional differences in warming that occur in the 1% CO2 experiments for each model.

Resource type

dataset

Resource locator

https://rda.ucar.edu/datasets/d583117/

protocol: https

applicationProfile: browser

name: Dataset Description

description: Related Link

function: information

https://rda.ucar.edu/datasets/d583117/dataaccess/

protocol: https

applicationProfile: browser

name: Data Access

description: Related Link

function: download

Unique resource identifier

code

codeSpace

Dataset language

Spatial reference system

code identifying the spatial reference system

Classification of spatial data and services

Topic category

climatologyMeteorologyAtmosphere

Keywords

Keyword set

keyword value

dataset

originating controlled vocabulary

title

reference date

date type

revision

effective date

2014-10-16

Keyword set

keyword value

CESM > NCAR Community Earth System Model

originating controlled vocabulary

title

reference date

date type

revision

effective date

2025-06-17

Keyword set

keyword value

EARTH SCIENCE > ATMOSPHERE > ATMOSPHERIC CHEMISTRY > CARBON AND HYDROCARBON COMPOUNDS > ATMOSPHERIC CARBON DIOXIDE

originating controlled vocabulary

title

reference date

date type

revision

effective date

2025-06-09

Geographic location

West bounding longitude

East bounding longitude

North bounding latitude

South bounding latitude

Temporal reference

Temporal extent

Begin position

End position

Dataset reference date

date type

publication

effective date

2025-06-23

Frequency of update

notPlanned

Quality and validity

Lineage

Conformity

Data format

name of format

version of format

Constraints related to access and use

Constraint set

Use constraints

Creative Commons Attribution 4.0 International License

Limitations on public access

None

Responsible organisations

Responsible party

organisation name

UCAR/NCAR - Research Data Archive

full postal address

National Center for Atmospheric Research

CISL/DECS

P.O. Box 3000

Boulder

80307

U.S.A.

telephone number

(303)-497-1833

facsimile number

303-497-1291

email address

chifan@ucar.edu

responsible party role

pointOfContact

Metadata on metadata

Metadata point of contact

organisation name

NCAR Research Data Archive

full postal address

National Center for Atmospheric Research

CISL/DECS

P.O. Box 3000

Boulder

80307

U.S.A.

facsimile number

303-497-1291

email address

rdahelp@ucar.edu

web address

https://rda.ucar.edu/

name: NCAR Research Data Archive

description: The Research Data Archive (RDA), managed by the Data Engineering and Curation Section (DECS) of the Computational and Information Systems Laboratory (CISL) at NCAR, contains a large and diverse collection of meteorological and oceanographic observations, operational and reanalysis model outputs, and remote sensing datasets to support atmospheric and geosciences research, along with ancillary datasets, such as topography/bathymetry, vegetation, and land use.

function: downlaod

responsible party role

pointOfContact

Metadata date

2025-06-23T14:05:01Z

Metadata language