4 March 2014 — Science experts say adaptation measures are now imperative to reduce infrastructure and property damage, after the CSIRO and Bureau of Meteorology’s third State of the Climate report, said Australia’s temperature was on the rise and there would be more heatwaves and extreme fire risk to come.
Temperatures had risen almost 1°C in the last century, the report said.
Bureau of Meteorology chief executive Dr Rob Vertessy said most of the warming had occurred since 1950
“Seven of the 10 warmest years on record in Australia have occurred since 1998,” Dr Vertessy said. “When we compare the past 15 years to the period 1951 to1980, we find that the frequency of very warm months has increased five-fold and the frequency of very cool months has decreased by around a third.”
He said extreme fire risk had increased over large swathes of Australia, and the fire season had also lengthened.
Professor Neville Nicholls from the School of Geography and Environmental Science at Monash University said that climate drivers of bushfire activity were increasing, causing “deaths and illness, infrastructure damage and property destruction”.
He said that Australia had begun to adapt to these risks, though more effort was needed.
“Heatwave alerts and other adaptations are offsetting some of the climate-driven risk increases,” Professor Nicholls said. “Nevertheless, we need to intensify our adaptation efforts because heatwaves and the risks of bushfires will likely continue to increase in frequency and severity.
“This adaptation would be simpler if politicians could slow the growth in emissions of the greenhouse gases that is the underlying cause of the increased risks of heat waves and bush fires.”
Dr Sarah Perkins, a research associate at the ARC Centre of Excellence for Climate System Science at the University of New South Wales, said the report findings were not surprising.
“The Australian 2014 State of the Climate report is consistent with the overwhelming amount of climate science literature,” Dr Perkins said.
“Conditions of heat and fire over the past two summers pretty much sum up what we have seen over the longer term. Future projections only continue these trends, towards hotter and longer heatwaves, more often, and longer fires seasons.
“Although we are not necessarily locked in to projections for the end of the century, we are in the shorter term, and so adaptation and mitigation procedures are imperative.”
Key findings were:
- Australia’s mean surface air temperature has warmed by 0.9°C since 1910
- seven of the ten warmest years on record have occurred since 1998
- over the past 15 years, the frequency of very warm months has increased five-fold and the frequency of very cool months has declined by around a third, compared to 1951-1980
- sea-surface temperatures in the Australian region have warmed by 0.9°C since 1900
- rainfall averaged across Australia has slightly increased since 1900, with a large increase in northwest Australia since 1970
- a declining trend in winter rainfall persists in southwest Australia
- autumn and early winter rainfall has mostly been below average in the southeast since 1990
Heatwaves and fire weather
- the duration, frequency and intensity of heatwaves have increased across large parts of Australia since 1950
- there has been an increase in extreme fire weather, and a longer fire season, across large parts of Australia since the 1970s
Future climate scenarios for Australia
- Australian temperatures are projected to continue to increase, with more hot days and fewer?cool days
- a further increase in the number of extreme fire-weather days is expected in southern and eastern Australia, with a longer fire season in these regions
- average rainfall in southern Australia is projected to decrease, with a likely increase in drought frequency and severity
- the frequency and intensity of extreme daily rainfall is projected to increase
- tropical cyclones are projected to decrease in number but increase in intensity