11D.5
Analysis of High-resolution Climate Change Simulations of Tropical Cyclones
Kevin J. E. Walsh, CSIRO, Aspendale, Vic., Australia; and K. C. Nguyen
A number of recent simulations have addressed the issue of the effect of climate change on tropical cyclones. Current understanding of this issue is briefly reviewed. Climate change simulations of relatively high horizontal resolution (30 km) for the Australian region are then analysed. These are DARLAM (Division of Atmospheric Research Limited Area Model) simulations which are multiply-nested within a CSIRO Mark 2 coupled model GCM run and a subsequent 125 km DARLAM run. Unlike previous simulations at 30 km resolution using DARLAM, these are "unbogussed" in that the climate model generates tropical cyclone-like vortices without the imposition of an artificial vortex. This modelling system gives a good simulation of observed tropical cyclone formation, although peak simulated wind speeds tend to be less than observed. The impact of climate change is then determined, including an analysis of changes in numbers and intensities of cyclones, as well as their regions of typical occurrence. These results are placed in the context of the remaining scientific uncertainties in these issues, which could affect their relevance for planning purposes.
Session 11D, Tropical Cyclone Simulation: Large-scale Effects and Climate Change (Parallel with Sessions 11A, 11B, and 11C)
Wednesday, 1 May 2002, 4:00 PM-5:30 PM
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