Content area
Full Text
huGhes, l. & sTeffen, W. (2013) Climate change in Victoria: trends, predictions and impacts. Proceedings of the Royal Society of Victoria 125(1/2): 5-13. ISSN 0035-9211. Correspondence: [email protected]
Australia's climate is changing, consistent with global trends. Continental average temperatures have increased nearly 1°C since the early 20th century, with warming accelerating since the 1950s. The number of extreme hot days is increasing, whereas the number of cold days and frosts is decreasing. With an average temperature over 1.0°C above the long-term mean, 2005 was Australia's warmest year on record; 2009 was the second warmest year on record. The decade 2000-2009 was Australia's warmest. Rainfall has been decreasing in the south-west and south-east of Australia, but increasing in the north-west. The ocean is warming and sea levels are rising, consistent with global averages. Consistent with global and national trends, Victoria's climate is already changing and will continue to do so, posing significant risks to the State. Over the past few decades Victoria has become hotter and drier, and these trends are likely to continue, together with an increasing intensity and/or frequency of extreme events, such as heatwaves, droughts, bushfires and floods, posing significant risks to the State's infrastructure, coasts, ecosystems, agriculture and health.
Key words: climate change, rainfall, sea level, Victoria, warming.
OBSERVED AND PROJECTED TRENDS IN CLIMATE AND ExTREME EVENTS
Temperature
MAxIMUM and minimum temperatures in south- east Australia have increased 1.1°C and 0.9°C, respectively, since 1960 (Ashcroft et al. 2012). The average number of record hot days per year has also increased; in Melbourne, the long-term average number of days per year above 35°C was 10 (Bureau of Meterology (BoM) 2012a) but, during the decade 2000-2009, the average number of days >35°C increased to 13 (BoM 2010). The January-February 2009 Melbourne heatwave event was consistent with the shift to more record hot weather. The summer of 2012-2013 was remarkable in the number of high temperature records set and for the intensity and extent of extreme hot weather (for details, see Climate Commission 2013).
As average temperatures continue to rise across Victoria, the number of hot days (>35°C) is expected to increase. In Melbourne, the number of hot days is projected to increase from the long-term average of 10 (BoM 2012a) to 15-26 days...