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Challenges and opportunities for improved understanding of regional climate dynamics

Abstract

Dynamical processes in the atmosphere and ocean are central to determining the large-scale drivers of regional climate change, yet their predictive understanding is poor. Here, we identify three frontline challenges in climate dynamics where significant progress can be made to inform adaptation: response of storms, blocks and jet streams to external forcing; basin-to-basin and tropical–extratropical teleconnections; and the development of non-linear predictive theory. We highlight opportunities and techniques for making immediate progress in these areas, which critically involve the development of high-resolution coupled model simulations, partial coupling or pacemaker experiments, as well as the development and use of dynamical metrics and exploitation of hierarchies of models.

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Fig. 1: Sea surface temperature trends from observations for the period 1979–2012 indicating the concept of inter-ocean-basin teleconnections.
Fig. 2: The influence of sharp SST gradients in the Gulf Stream on the hydrological cycle of individual storms and their rectification on the mean climate state.
Fig. 3: Schematic indicating the concept of the ‘hierarchies of models’.

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Acknowledgements

We acknowledge the support of CLIVAR in setting up the Climate Dynamics Panel and their travel support for hosting panel meetings. M.C. and S.M. conceived the paper and also co-chair the CLIVAR Climate Dynamics Panel. All other authors contributed to the writing. C.O.R. produced Fig. 2 and M.C. acknowledges support from NERC NE/N018486/1. N.K. acknowledges support from the ERC (grant 648982).

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Collins, M., Minobe, S., Barreiro, M. et al. Challenges and opportunities for improved understanding of regional climate dynamics. Nature Clim Change 8, 101–108 (2018). https://doi.org/10.1038/s41558-017-0059-8

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