Beborah Smith, Sydney Morning Herald 28 Nov 09;
MORE than 70 Australian marine scientists have called for immediate action to reduce greenhouse gas emissions after the release of the first report card on the impact of climate change on the marine environment.
Oceans around the continent have warmed and become more acidic and the East Australian Current has strengthened, bringing hotter, saltier water 350 kilometres further south than 60 years ago.
This has caused coral bleaching and is the likely cause of a 10 per cent reduction in growth rates of corals on the Great Barrier Reef, according to the report, Marine Climate Change in Australia, 2009 Report Card.
Other effects include a spread of destructive sea urchins in Tasmania, the death of sea turtles in Queensland and the spread of mangroves into freshwater wetlands in northern Australia.
The report, by scientists from universities, state and territory environmental agencies, the Australian Institute of Marine Science, the Bureau of Meteorology and CSIRO, warns that two degrees of further warming is already unavoidable. "A delay in reducing human-related emissions will result in even greater levels of climate change and subsequent impacts on marine species and habitats," it concludes.
Elvira Poloczanska, of the CSIRO Climate Change Adaptation Flagship, said ocean warming also meant some subtropical plants and animals were moving south into temperate waters. This had already severely affected giant kelp forests in Tasmania.
The report card, which is to be updated every two years, identifies where impacts have occurred, the predicted effects of climate change by 2030 and 2100, and scientific confidence levels in those predictions. It also outlines strategies for adapting to climate change, such as removing sea walls, increased surveillance for harmful algal blooms and managing the breeding habitats for sea birds better. A University of Wollongong researcher, Helen McGregor, said it was a "call to arms" for scientists, policymakers and the public to do everything possible to reduce greenhouse gas emissions.
Stingers likely to ravage southeast Queensland
Melanie Christiansen and Kate Higgins, The Courier-Mail 27 Nov 09;
THE dangerous stingers that close northern Queensland beaches every summer could migrate as far south as the Gold Coast, a leading climate scientist has warned.
Dr Anthony Richardson said warming oceans could drive irukandji and box jellyfish south in search of cooler waters.
"A lot of marine life, as the environment warms, it gets too warm for them in that particular place and they start to move towards the poles where it's cooler," he said.
"So a lot of venomous jellyfish in tropical north Queensland – which close beaches every year – could potentially move down as waters get warmer and the East Australian Current gets stronger into southeast Queensland and northern NSW.
"It could have repercussions. The tourist industry in southeast Queensland is worth billions of dollars every year."
Dr Richardson delivered his warning at the launch of a report card on marine climate change impacts – the work of more than 70 scientists from 35 Australian institutions led by the CSIRO.
National Climate Change Adaptation Research Facility director Dr Jean Palutikof said jellyfish migrating south was a " pretty distressing" prospect. But she said the threat to Australia's iconic Great Barrier Reef was a more certain outcome of climate change.
"It's got a high degree of certainty associated with the threat," Dr Palutikof said.
Dr Alistair Hobday, of the CSIRO climate adaptation project, also warned of a looming risk to mangroves, especially in northern Queensland.
"Mangroves are very important in buffering and protecting us from storms," he said. "If we lose those from some areas, we'll have many more storm surges and flooding of coastal properties.
"It will impact on people and their houses on the coast."
Dr Hobday said rising acidity could also have big ramifications for the ocean food chain.
But he emphasised there could also be some welcome changes as oceans warm.
"For recreational fishermen in southern Australia, though, more tropical fish species will be found further south, like yellowfin tuna or yellow tail kingfish – very popular recreational species," he said. "And that will mean quite a good opportunity for people."
The marine climate change report card, detailing known and predicted changes, is available online at www.oceanclimatechange.org.au
Australian marine scientists issue call to arms after devastating report
posted by Ria Tan at 11/28/2009 01:36:00 PM
labels climate-change, global, marine, reefs