Search from over 60,000 research works

Advanced Search

UKESM1.1: development and evaluation of an updated configuration of the UK Earth System Model

[thumbnail of Open Access]
Preview
Mulcahy gmd-16-1569-2023 UKESM1-1.pdf - Published Version (16MB) | Preview
Available under license: Creative Commons Attribution
Add to AnyAdd to TwitterAdd to FacebookAdd to LinkedinAdd to PinterestAdd to Email

Mulcahy, J. P. orcid id iconORCID: https://orcid.org/0000-0002-0870-7380, Jones, C. G. orcid id iconORCID: https://orcid.org/0000-0002-7221-8127, Rumbold, S. orcid id iconORCID: https://orcid.org/0000-0001-8138-4541, Kuhlbrodt, T. orcid id iconORCID: https://orcid.org/0000-0003-2328-6729, Dittus, A. orcid id iconORCID: https://orcid.org/0000-0001-9598-6869, Blockley, E. W. orcid id iconORCID: https://orcid.org/0000-0002-0489-4238, Yool, A. orcid id iconORCID: https://orcid.org/0000-0002-9879-2776, Walton, J. orcid id iconORCID: https://orcid.org/0000-0001-7372-178X, Hardacre, C., Andrews, T., Bodas-Salcedo, A., Stringer, M. orcid id iconORCID: https://orcid.org/0000-0003-4061-5299, de Mora, L. orcid id iconORCID: https://orcid.org/0000-0002-5080-3149, Harris, P. orcid id iconORCID: https://orcid.org/0000-0002-4834-7746, Hill, R., Kelley, D. orcid id iconORCID: https://orcid.org/0000-0003-1413-4969, Robertson, E. and Tang, Y. (2023) UKESM1.1: development and evaluation of an updated configuration of the UK Earth System Model. Geoscientific Model Development, 16 (6). pp. 1569-1600. ISSN 1991-9603 doi: 10.5194/gmd-16-1569-2023

Abstract/Summary

Many Coupled Model Intercomparison Project phase 6 (CMIP6) models have exhibited a substantial cold bias in the global mean surface temperature (GMST) in the latter part of the 20th century. An overly strong negative aerosol forcing has been suggested as a leading contributor to this bias. An updated configuration of UK Earth System Model (UKESM) version 1, UKESM1.1, has been developed with the aim of reducing the historical cold bias in this model. Changes implemented include an improved representation of SO2 dry deposition, along with several other smaller modifications to the aerosol scheme and a retuning of some uncertain parameters of the fully coupled Earth system model. The Diagnostic, Evaluation and Characterization of Klima (DECK) experiments, a six-member historical ensemble and a subset of future scenario simulations are completed. In addition, the total anthropogenic effective radiative forcing (ERF), its components and the effective and transient climate sensitivities are also computed. The UKESM1.1 preindustrial climate is warmer than UKESM1 by up to 0.75 K, and a significant improvement in the historical GMST record is simulated, with the magnitude of the cold bias reduced by over 50 %. The warmer climate increases ocean heat uptake in the Northern Hemisphere oceans and reduces Arctic sea ice, which is in better agreement with observations. Changes to the aerosol and related cloud properties are a driver of the improved GMST simulation despite only a modest reduction in the magnitude of the negative aerosol ERF (which increases by +0.08 W m−2). The total anthropogenic ERF increases from 1.76 W m−2 in UKESM1 to 1.84 W m−2 in UKESM1.1. The effective climate sensitivity (5.27 K) and transient climate response (2.64 K) remain largely unchanged from UKESM1 (5.36 and 2.76 K respectively).

Altmetric Badge

Item Type Article
URI https://reading-clone.eprints-hosting.org/id/eprint/111436
Item Type Article
Refereed Yes
Divisions Science > School of Mathematical, Physical and Computational Sciences > NCAS
Science > School of Mathematical, Physical and Computational Sciences > Department of Meteorology
Publisher European Geosciences Union
Download/View statistics View download statistics for this item

Downloads

Downloads per month over past year

University Staff: Request a correction | Centaur Editors: Update this record

Search Google Scholar