Summertimemaximum andminimum temperature coupling asymmetry over Australia determined usingWRF

Using the Weather and Research Forecasting model we derive the first estimates for intraseasonal soil moisture-atmosphere coupling strength for the Australian summer climate using methodology adapted from the Global Land-Atmosphere Coupling Experiment. We examine the variations in coupling strength by perturbing the background climate (dry versus wet year) and the model physics (planetary boundary layer or cumulus scheme). For all choices of model physics, results identify Australia as a “hot spot” of soil moisture-atmosphere coupling for both mean and maximum temperatures. For the wet case, results are consistent for maximum temperature for all physics choices. Results diverge more for maximum temperature in the chosen dry year. The coupling of soil moisture with minimum temperature is weaker but consistent for all choices of model physics or whether a wet or dry year is used. Coupling strength for precipitation is weak and not statistically significant irrespective of the choice of model physics.