Map 1: GCM 6 month mean summer precipitation.
Climate Futures for Tasmania, breaks new ground in making climate modelling science accessible to the community. This project, now in its final year, has confidently demonstrated the value of dynamically downscaling global climate models to generate locally relevant and usable information.
By using Tasmania’s climate history, global climate models, future climate scenarios and a huge amount of computer processing, ACE is able to make quantitative projections of Tasmania’s future climate. New information on climate change projections for Tasmania to the end of the 21st century have been generated by ’dynamically downscaling’ six global climate models, each using two of the emission scenarios used by the Intergovernmental Panel on Climate Change.
The attached maps show how Tasmanian summer rainfall is projected to change during this century (A2 emissions scenario). Map 1 (refer image above) shows the projected change using input from global climate models. Map 2 (see link at bottom of page) shows the change from the intermediate resolution (60 km) model output. Map 3 (see link at bottom of page) shows the projected change from the fine-scale (14 km) model output. All three figures show the west coast getting drier during summer. In the GCM, the east coast is drying, with the boundary between the drying and wetting region lying just off the coast of Tasmania. As we increase the resolution of the models (From Map 1, to Map 2, then Map 3), we see a projected increase in rainfall along the east coast. This result illustrates the value of dynamical downscaling: as we increase the resolution we can better resolve the interplay between large-scale climate patterns, topography and rainfall and allows a better definition of the boundary between the regions of increasing and decreasing rainfall.
The emerging results suggest that climate change will affect different parts of Tasmania differently, and, because of its geographical position and close proximity to the Southern Ocean, Tasmania will have smaller increases in average temperature than mainland Australia. The skill of the dynamical downscaling is also providing a new picture of how the spatial pattern of the changes may be differ across Tasmania.
Map 2: 60Km 6-month mean summer precipitation
Map 3: 14km six-month mean summer precipitation