Seasonal climate summary southern hemisphere (autumn 2014): tropical Pacific experiences strong push towards El Niño

Abstract

Southern hemisphere circulation patterns and associated anomalies for the austral autumn 2014 are reviewed, with emphasis given to the Pacific Basic climate indicators and Australian rainfall and temperature patterns. The tropical Pacific saw a number of indicators make a strong push toward El Niño during the autumn months. In the eastern tropical Pacific, warm sea surface temperature anomalies emerged during autumn, while in March the Southern Oscillation Index (SOI) saw its most negative monthly value since February 2010 (the end of the last El Niño), with –13.3. Outside the tropics, the Southern Annular Mode (SAM) was slightly positive, but within the neutral range during autumn. For the Australian region, sea surface temperatures ranked as fourth warmest on record. The Australian area-averaged land surface maximum temperature anomaly was +1.16 °C for autumn, sixth-warmest on record. Similarly, minimum temperatures were also above average (+1.14 °C) and third-warmest on record. Spatially, both maximum and minimum temperatures showed a virtual absence of below average temperatures for autumn across Australia. Rainfall was nine per cent below average for Australia, with a wetter than average autumn for much of the south to southeast, and a drier than average autumn for southwest Queensland and parts of northwest Western Australia.