Navigation Links
Understanding autumn rain decline in SE Australia
Date:5/23/2008

According to a report from a CSIRO Wealth From Oceans Flagship study published this week in the science journal Geophysical Research Letters since 1950 Victoria has suffered a 40 per cent decline in autumn rainfall (March to May) compared to the average recorded between 196190.

The reports authors, CSIROs Dr Wenju Cai and Tim Cowan, say that the decline has been most prominent in May, which accounts for about half of the total seasonal reduction.

The identified causes show imprints of climate change influences, in part through a reduction in the number of La Nia events, and in part through changing weather systems originating from the subtropical Indian Ocean that are conducive to late autumn rainfall across Victoria.

The researchers found that since 1950 the spatially alternating high and low pressure systems (called pressure wave-trains) conducive to rainfall over southern Victoria in May have been weakening, leading to rising sea level atmospheric pressure over south-east Australia.

This weakening is reinforced by a warming of the Indian Ocean, which is at least in part due to global warming, Dr Cai says. This suggests that a component of climate change is active in southern Victoria receiving less rainfall.

Influences from the Indian Ocean sector occur in conjunction with those from the Indonesian Throughflow region, to the north of Australia. Dr Cai says higher sea surface temperatures in the Throughflow region are conducive to rainfall in central and northern south-east Australia, through the familiar tropical northwest cloud bands, which deliver rainfall to the region.

Through April and May, large increases in sea surface temperatures in the region are usually associated with a transition from an El Nio to a La Nia event, as part of cycle of the El Nio-Southern Oscillation, he says.

Mr Cowan says that in recent decades, there have been more El Nio events than La Nias. As the system spends more time in an El Nio phase, and less time transitioning to a La Nia, south-east Australia receives less rainfall. This El Nio-like behaviour pattern of the Pacific system is also consistent with what is expected from climate change, as recent studies have shown, he says. Victoria is not alone among states experiencing rainfall declines. During the past 50 years there has been a decreasing trend in rainfall over much of Australia. In south-west Western Australia the trend is strongest in winter; and in southern Queensland strongest in summer.


'/>"/>

Contact: Craig Macaulay
Craig.Macaulay@csiro.au
61-362-325-219
CSIRO Australia
Source:Eurekalert

Related biology news :

1. A study by the MUHC and McGill University opens a new door to understanding cancer
2. Understanding hypertension in African Americans proves elusive
3. Systems Biology poised to revolutionize the understanding of cell function and disease
4. Gregory Hannon wins 2007 Paul Marks Prize for contributions to understanding and treating cancer
5. Understanding, combating foodborne pathogens E. coli 0157 and salmonella
6. Researchers discover important tool in understanding differentiation in human embryonic stem cells
7. Atmospheric measuring device for understanding smog formation
8. Researchers move 2 steps closer to understanding genetic underpinnings of autism
9. Scientists expand understanding of how river carbon impacts the Arctic Ocean
10. From delicious to death: Understanding taste
11. USP Convention and Chinese Pharmacopoeia Commission sign Memorandum of Understanding
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/15/2016)... 2016 Transparency Market Research ... Market by Application Market - Global Industry Analysis Size Share ... the report, the  global gesture recognition market  was ... is estimated to grow at a CAGR of ... Increasing application of gesture recognition technology ...
(Date:6/7/2016)... 7, 2016  Syngrafii Inc. and San Antonio ... that includes integrating Syngrafii,s patented LongPen™ eSignature "Wet" ... collaboration will result in greater convenience for SACU ... while maintaining existing document workflow and compliance requirements. ... Highlights: ...
(Date:6/2/2016)... June 2, 2016   The Weather Company , an ... Ads, an industry-first capability in which consumers will be able ... to ask questions via voice or text and receive relevant ... Marketers have long sought an advertising solution ... can be personal, relevant and valuable; and can scale across ...
Breaking Biology News(10 mins):
(Date:6/24/2016)... ... June 24, 2016 , ... Researchers at the Universita Politecnica ... in people with peritoneal or pleural mesothelioma. Their findings are the subject of a ... , Diagnostic biomarkers are signposts in the blood, lung fluid or tissue of ...
(Date:6/23/2016)... , ... June 23, 2016 , ... ... pleased to announce the launch of their brand, UP4™ Probiotics, into Target stores ... 35 years, is proud to add Target to its list of well-respected retailers. ...
(Date:6/23/2016)... 2016 /PRNewswire/ - FACIT has announced the creation ... biotechnology company, Propellon Therapeutics Inc. ("Propellon" or "the ... a portfolio of first-in-class WDR5 inhibitors for the ... WDR5 represent an exciting class of therapies, possessing ... for cancer patients. Substantial advances have been achieved ...
(Date:6/23/2016)... , June 23, 2016 Houston ... with the Cy-Fair Sports Association to serve as ... the agreement, Houston Methodist Willowbrook will provide sponsorship ... and connectivity with association coaches, volunteers, athletes and ... with the Cy-Fair Sports Association and to bring ...
Breaking Biology Technology: