Sea level projections for the Australian region in the 21st century

Sea level rise exhibits significant regional differences. Based on Coupled Model Intercomparison Project Phase 5 (CMIP5) models, sea level projections have been produced for the Australian region by taking account of regional dynamic changes, ocean thermal expansion, mass loss of glaciers, changes in Greenland and Antarctic ice sheets and land water storage, and glacial isostatic adjustment. However, these regional projections have a coarse resolution (similar to 100km), while coastal adaptation planners demand finer scale information at the coast. To address this need, a 1/10 degrees near-global ocean model driven by ensemble average forcings from 17 CMIP5 models is used to downscale future climate. We produce high-resolution sea level projections by combining downscaled dynamic sea level with other contributions. Off the southeast coast, dynamic downscaling provides better representation of high sea level projections associated with gyre circulation and boundary current changes. The high-resolution sea level projection should be a valuable product for detailed coastal adaptation planning.