Teleconnectivity of climate indices and their spatial temporal influence on south Australian rainfall processes

The spatial and temporal influences of climate indices on South Australian (SA) rainfall processes and their teleconnectivity were investigated in this study. Recent records of monthly rainfall and climate index values from 1981 to 2010 were analysed for 53 rainfall stations, located across eight SA natural resources management regions. The Pearson, Kendall and Spearman correlation tests were applied between rainfall and climate indices and between the climate indices themselves. Both the principal component analysis and factor analysis confirmed that SOI, Niño3.4 and DMI are the most influential climate indices in the region. SA summer (December to February) rainfall was found influenced by the SOI index in the south east SA region, particularly in December and January. Some influences of Niño3.4 in the Arid Lands region were also evident. In autumn (March to May), the influences of both SOI and DMI were evident in the Arid Lands region in May. DMI influence in autumn was found confined to the south east part of SA. Winter rainfall in the south and east parts of SA was identified heavily influenced by both SOI and DMI index. Both SOI and DMI were found significantly correlated in winter. Spring rainfall is influenced by DMI in the south and east parts of SA, particularly in September and October. In terms of ENSO phenomena, whilst both SOI and Niño3.4 were identified correlated, SOI was found more to be influential than Niño3.4 for SA rainfall. The exploration of teleconnectivity of potential climate indices and their spatial temporal influences on SA rainfall processes help developing regional climate models and climate downscaling techniques in the region.