Initialization, Prediction and Diagnosis of the Rapid Intensification of Tropical Cyclones using the Australian Community Climate and Earth System Simulator, ACCESS

Abstract : The main long and short term objectives are: (a) To develop and apply ACCESS-based numerical systems to perform nested, high-resolution data assimilation, initialization and forecast experiments for rapid and slow intensification events. (b) To use the outcomes from (a) to investigate assimilation, prediction and dynamics of environmental influences and internal structure change during rapid intensification events. (c) To explore advanced hybrid ensemble-4DVAR data assimilation techniques to better initialize and validate TC structures (including the intense inner core and storm asymmetries) consistent with the large scale environment (LSE) of TCs. (d) To use sensitivity experiments and ensemble techniques to (i) understand the variability in simulations of RI, and (ii) estimate the highly anisotropic, flow dependent error covariances required for effective TC data assimilation. (e) To use idealised, synthetic TC structures in initial conditions, to investigate the sensitivity of RI prediction to vortex structure. (f) To investigate the use of additional data sources and new assimilation techniques for initialization of intense TC vortices without the use of a synthetic vortex.