Jan 27, 2015

Climate Change in Australia - Technical Report

Penny Whetton, Marie Ekström, Chris Gerbing, Michael Grose, Jonas Bhend, Leanne Webb and James Risbey
CSIRO and the Australian Bureau of Meteorology
  • Provides an assessment of observed climate change in Australia and its causes, and details projected future changes over the 21st century
  • Finds Australian average surface air temperature has increased by 0.9 °C since 1910, and increasing greenhouse gases have contributed to this rise
  • Finds that since 2001, the number of extreme heat records in Australia has outnumbered extreme cool records by almost 3 to 1 for daytime maximum temperatures and almost 5 to 1 for night-time minimum temperatures 
  • Observes an intensification of the subtropical ridge (the high pressure belt over Australia), an expansion of the Hadley Cell (a circulation in the northsouth direction connecting tropical and mid-latitude areas), and a trend to a more positive Southern Annular Mode (a hemispheric mode of variability associated with weaker than normal westerly winds and higher pressures over southern Australia)
  • Finds heavy daily rainfall has accounted for an increased proportion of total annual rainfall over an increasing fraction of the Australian continent since the 1970s
  • Finds Australian average rainfall has been increasing since the 1970s, mainly due to an increase in wet season rain in northern Australia
  • Observes that for 1966 to 2009, the average rate of relative sea level rise from observations along the Australian coast was 1.4 ± 0.2 mm/year, and 1.6 ± 0.2 mm/year when the sea level variations directly correlated with the Southern Oscillation Index (SOI) are removed