Abstract/Summary

Climate drivers are more predictable than the rainfall patterns themselves and as such it is important to identify and understand the influence of climate drivers on inter-annual and decadal variations in Queensland rainfall. Identifying these climate drivers in historical records would provide a baseline against which to evaluate the climate model simulations of these drivers and Queensland rainfall. In addition understanding of the climate driver/rainfall relationship would greatly improve seasonal rainfall prediction. Empirical orthogonal teleconnection (EOT) analysis is applied to the 1900-2008 gridded SILO rainfall dataset to determine the climate drivers of seasonal rainfall in Queensland. EOT analysis identifies coherent spatial patterns of rainfall variability in the historical dataset, allowing the identification of climate drivers of specific regional rainfall variations. Most of the published work to date has not been able to identify the influence of each individual driver on Queensland rainfall as most rainfall seasons were significantly correlated with more than one driver. It is therefore necessary to decompose spatially coherent variations in Queensland rainfall and link these variations to individual driving atmospheric phenomena. To achieve this a combination of ERA-40, the new ECMWF Interim Reanalyses and other observational datasets, particularly those developed in Queensland and by the Met Office Hadley Centre, to investigate the processes and phenomena associated with the behaviour of Queensland rainfall over the last few decades were used.