David J. Lorenz

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The change in the extratropical circulation under global warming is studied using the climate models participating in the Intergovernmental Panel on Climate Change (IPCC) fourth assessment report. The IPCC models predict a strengthening and a poleward shift of the tropospheric zonal jets in response to global warming. The change in zonal jets is also(More)
The present study focuses on diagnosing the intermodel variability of nonzonally averaged NH winter jet stream portrayal in 17 global climate models (GCMs) from phase three of the Coupled Model In-tercomparison Project (CMIP3). Relative to the reanalysis, the ensemble-mean 300-hPa Atlantic jet is too zonally extended and located too far equatorward in GCMs.(More)
Twenty-eight years of NCEP–NCAR reanalysis data are employed in a composite analysis of the structure and evolution of the large-scale circulation associated with rapid, subseasonal, westward retractions of the Northern Hemisphere Pacific jet. Nineteen Pacific jet retractions are identified in the dataset. The salient characteristics of these transitions(More)
The anthropogenic climate change impacts on the eddy–jet system include an intensified midlatitude jet stream and an elevated tropopause, as well as a poleward-shifted jet. While both responses are evident in phase 3 of the Coupled Model Intercomparison Project (CMIP3) ensemble mean twenty-first-century projections , uncertainty in the poleward shift(More)
Increasingly, ecological modellers are integrating paleodata with future projections to understand climate-driven biodiversity dynamics from the past through the current century. Climate simulations from earth system models are necessary to this effort, but must be debiased and downscaled before they can be used by ecological models. Downscaling methods and(More)
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