Automated parameter tuning applied to sea ice in a global climate model

Lettie A. Roach, Simon F. B. Tett, Michael J. Mineter, Kuniko Yamazaki, Cameron D. Rae

Research output: Contribution to journalArticlepeer-review

Abstract

This study investigates the hypothesis that a significant portion of spread in climate model projections of sea ice is due to poorly-constrained model parameters. New automated methods for optimization are applied to historical sea ice in a global coupled climate model (HadCM3) in order to calculate the combination of parameters required to reduce the difference between simulation and observations to within the range of model noise. The optimized parameters result in a simulated sea-ice time series which is more consistent with Arctic observations throughout the satellite record (1980-present), particularly in the September minimum, than the standard configuration of HadCM3. Divergence from observed Antarctic trends and mean regional sea ice distribution reflects broader structural uncertainty in the climate model. We also find that the optimized parameters do not cause adverse effects on the model climatology. This simple approach provides evidence for the contribution of parameter uncertainty to spread in sea ice extent trends and could be customized to investigate uncertainties in other climate variables.
Original languageEnglish
Pages (from-to)51-65
Number of pages15
JournalClimate Dynamics
Volume50
Issue number1-2
Early online date14 Mar 2017
DOIs
Publication statusPublished - Jan 2018

Keywords

  • Optimization
  • Sea ice
  • Parameters
  • Climate model
  • CMIP5 MODELS
  • COUPLED CLIMATE
  • OCEAN-MODEL
  • EXTENT
  • SIMULATIONS
  • UNCERTAINTY
  • CIRCULATION
  • PREDICTIONS
  • SENSITIVITY
  • PERFORMANCE

Fingerprint Dive into the research topics of 'Automated parameter tuning applied to sea ice in a global climate model'. Together they form a unique fingerprint.

Cite this