Large ensembles as a tool to understand changes in climate extremes: variability, trends and emergence of forced changes
Abstract
The computational cost of running climate model simulations has steadily declined in recent years, providing a new opportunity for modelling centres to generate large ensembles of climate model simulations. Several such large ensembles have been produced in recent years, which has enabled researchers to better study the importance of internal variability in estimations of historical and future forced climatic changes.
Climate extremes constitute a huge societal challenge, however, disentangling forced changes in historical and projected changes in the presence of large unforced variability has often proven difficult. Large ensembles provide a larger number of extreme events to analyse, and provide more robust estimates of changes in e.g. return times. The greater number of independent realisations also enables assessments of the sensitivity of detected changes to ensemble size. Here, we present recent published research on emergence of climate extremes and discuss how large ensembles of climate model simulations can be utilised to inform assessments of present-day and future risk associated with climate extremes. Examples from a new HadGEM3-GC3.1 large ensemble will be presented. In this ensemble, four sub-ensembles with different magnitudes of anthropogenic aerosol forcing provide an opportunity to consider sensitivity of changes in extremes to differences in aerosol forcing and assess the magnitude of internally generated variability more broadly.- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2018
- Bibcode:
- 2018AGUFMGC32B..01D
- Keywords:
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- 1616 Climate variability;
- GLOBAL CHANGEDE: 1626 Global climate models;
- GLOBAL CHANGEDE: 1637 Regional climate change;
- GLOBAL CHANGE