Weather change predictions for the South Coast

A recent climate science workshop hosted by South Coast NRM in cooperation with the Commonwealth Scientific and Industrial Research Organisation (CSIRO) and the Bureau of Meteorology (BOM) highlighted a variety of information about climate change and variability in our region.

Climate science experts stated there is likely to be a temperature increase during all seasons with more warm and fewer very cold days. Winter rainfall is likely to decrease and while change in summer rainfall is uncertain, extreme rainfall intensity will increase.

It is expected natural rainfall variability will continue in the future and may mask any trend in average rainfall for some decades to come, particularly during the summer.

South Coast NRM climate change project leader Kaylene Parker said the workshop provided a unique opportunity to hear from climate science experts and review some of the apparent changes in climate which people have noticed in the region.

“The workshop was an invaluable source of information exchange between climate scientists and locals whose records and observations will aid the Bureau of Meteorology fine tune its modelling”, Ms Parker said.

“Some of the anomalies on the South Coast include increasing rainfall in areas around the Kalgan River and near Jerramungup”.

“Another key climate feature in our region is the Southern Annular Mode also known as the Antarctic Oscillation. This is the north–south movement of the westerly wind belt circling Antarctica and dominating the middle to higher latitudes of the southern hemisphere.It appears this will have a greater influence over the rainfall in our region and can override the effect of El Nina and El Niño in some years”, Ms Parker said.

CSIRO’s Dr Pandora Hope suggested the higher rainfall around the Kalgan River was possibly due to more intense high pressure systems over the south-west which can bring more easterly rain from the ocean.

“We have shown these high pressure systems have increased in intensity and are pushing the low pressure systems further south,” Dr Hope said.

CSIRO has observed the temperature trend increase from 1910 was between 0.05 and 0.15 C per decade, while in the last 43 years the warming has risen to 0.20 C per decade in some South Coast locations.

South Coast NRM will continue to work with CSIRO, BOM and UWA’s Centre for Excellence in Natural Resource Management as part of a national project to review the impact of the new climate modelling data on biodiversity, agriculture and water resources and the region’s capacity to adapt to these changes.

The latest State of the Climate report can be found at http://www.bom.gov.au/state-of-the-climate/