Please select your home edition
Edition
Bakewell-White Yacht Design

Aerosols – their part in our rainfall

by CSIRO on 17 Feb 2009
CSIRO atmosphere expert, Dr Leon Rotstayn. Photo: Bruce Miller © Copyright CSIRO Australia http://www.csiro.au
Aerosols may have a greater impact on patterns of Australian rainfall and future climate change than previously thought, according to leading atmospheric scientist, CSIRO’s Dr Leon Rotstayn.

'We have identified that the extensive pollution haze emanating from Asia may be re-shaping rainfall patterns in northern Australia but we wonder what impact natural and human-generated aerosols are having across the rest of the country,' Dr Rotstayn said.

Aerosols are fine particles suspended in the atmosphere. Sources of human-generated aerosols include industry, motor vehicles and vegetation burning. Natural sources include volcanoes, dust storms and ocean plankton. Human-generated aerosols have long been known to exert a cooling effect on climate. This has partly masked the warming effect of increasing greenhouse gases. As aerosol pollution is predicted to decrease over the next few decades, unmasking of the greenhouse effect may lead to accelerated global warming.

However, in an address to the International Conference on Southern Hemisphere Meteorology and Oceanography in Melbourne, Dr Rotstayn said aerosols are much more than a 'negative greenhouse gas' because they can actively force changes in winds and ocean currents by altering the distribution of solar heating at the earth’s surface.

'We have identified that the extensive pollution haze emanating from Asia may be re-shaping rainfall patterns in northern Australia but we wonder what impact natural and human-generated aerosols are having across the rest of the country,'

Dr Rotstayn said 'Recent climate modelling at CSIRO shows that there may be important effects on Australian climate due to aerosol pollution from the Northern Hemisphere. These include an increase of rainfall in north-western Australia, and an increase of air pressure over southern Australia, which may have contributed to less rainfall there.

'New simulations with the CSIRO climate model also show big improvements in the simulation of El Niño and the associated natural rainfall variability over eastern Australia, when natural and human-generated aerosols are included in the model. Natural aerosol includes Australian dust, which may be the key factor that improved our simulation. A realistic simulation of natural rainfall variability is essential if a climate model is to be used to improve our understanding of Australian rainfall changes.'

Dr Rotstayn said that further research into how aerosols are influencing climate and rainfall patterns across Australia is critical to scientists’ ability to more accurately predict the longer-term effects of climate change.

'It is crucial to quantify the relative roles of different drivers of recent Australian rainfall changes. A rainfall decline attributed to natural variability will be a passing phenomenon, and changes forced by human-generated aerosols are likely to be more short-term than changes forced by increasing greenhouse gases. The implications for decision makers will be very different, depending on whether the drivers are long-term or short-term,' Dr Rotstayn said.

The Centre for Australian Weather and Climate Research (CAWCR) - http://www.cawcr.gov.au/research/spcv/research_areas.php

http://www.csiro.com.au
Colligo Marine 660x82Newport Boat Show 2016 660x82InSunSport - NZ

Related Articles

Clipper Round the World Yacht Race - Crew catch up - Meet Dhruv Boruah
After crew members have completed their global ocean adventure, some go back to their previous lives and occupations After crew members have completed their global ocean adventure, some go back to their previous lives and occupations, some decide on a future in the marine industry, some take time out to assess their next move in life and others seek their next challenge.
Posted today at 5:49 am
SoftBank Team Japan achieve first foiling tack
SoftBank Team Japan announced today that they cracked foiling tack earlier this year while training with their AC45 boat SoftBank Team Japan announced today that they cracked the foiling tack earlier this year while training with their AC45 Sport test boat in Bermuda.
Posted on 26 Aug
The Clipper Race turns 20!
Throughout the race, tales of crew celebrating birthdays on board filter back and they are always a special occasion Throughout the race, tales of Clipper Race crew celebrating their birthdays on board filter back and they are always a special occasion, likely to remain a completely unique event in their lifetime.
Posted on 23 Aug
America's Cup - Architect of NZ Qualifier withdrawal steps down
The Commissioner for the America's Cup General Dr. Harvey Schiller has stepped down from the role The Commissioner for the America's Cup General Dr. Harvey Schiller has stepped down from the role and will finish at the end of the month. The move was confirmed today by America's Cup correspondent Bernie Wilson of the Associated Press.
Posted on 23 Aug
An Q&A with Steve and Heidi Benjamin about the NYYC’s 2016 Queen’s Cup
Sail-World caught up with Steve and Heidi Benjamin to learn more about Heidi’s historic win in the NYYC’s Queen’s Cup. When it comes to U.S. Grand Prix sailing, it’s hard not to encounter the names of Steve and Heidi Benjamin. The two highly polished sailors have been successfully campaigning their series of yachts, named SPOOKIE, for years, starting first with a Carkeek 40 and progressing to their TP52. I caught up with Steve and Heidi to learn more about Heidi’s historic win in the NYYC’s Queen’s Cup
Posted on 19 Aug
PredictWind - One stop shop
PredictWind have taken the bold step of adding government provided forecasts to their award winning forecasting software PredictWind the world leader in forecasting believe that more is better, and have taken the bold step of adding government provided forecasts to their award winning forecasting software.
Posted on 15 Aug
Rio 2016 - Fresher breezes expected inside and outside on Day 3
Stronger winds are expected for the third day of racing in the 2016 Olympic Sailing Regatta in Rio de Janeiro. Stronger winds are expected for the third day of racing in the 2016 Olympic Sailing Regatta in Rio de Janeiro. Two of the fleet scheduled to race outside on the Atlantic Ocean course off Copacabana Beach, while the 470 Men and Women will race inside on Guananara Bay.
Posted on 10 Aug
35 Copa del Rey Mapfre - Armin Strom Sailing Team in action
Armin Strom Sailing Team remain in contention for the top of the podium throughout the 35 Copa del Rey Mapfre this week. Heading the leaderboard from the start and quickly finding a ‘turbo’ foiling mode saw Armin Strom Sailing Team remain in contention for the top of the podium throughout the 35 Copa del Rey Mapfre this week.
Posted on 8 Aug
American Windsurfing Tour – Final day
Ferdinando Loffreda slashed his foot open in the campo last night so retires from the Pro bracket. Ferdinando Loffreda slashed his foot open in the campo last night so retires from the Pro bracket.
Posted on 7 Aug
35 Copa del Rey Mapfre - Final day images by Carlo Borlenghi
Carlo Borlenghi provided this gallery of images from the final day. Carlo Borlenghi provided this gallery of images from the final day.
Posted on 7 Aug