7000-year-old corals of Moreton Bay tell their story

Posted on August 4, 2009 by ovehblog

The 7000-year-old coral communities of Moreton Bay are telling a curious tale, expanding when sea-levels rise or water quality improves, then declining when current circulation becomes more restricted.

Intriguing new insights into the behaviour of corals and fish under changing climatic conditions will be presented by leading marine researchers at a public forum in Brisbane this coming Friday.

Professor John Pandolfi from the University of Queensland and ARC Centre of Excellence for Coral Reef Studies and his team have been dating the corals of Moreton Bay and finding they have undergone surges of growth, probably triggered by subtle changes in sea level and water conditions.

“We’ve found coral communities up to 7000 years old showing these curious growth episodes – the last one started about 400 years ago. When coral reef growth slows or stops in the Bay, it appears to correspond with a decline in the current circulation and an increase in turbidity.”

The team has also found clear evidence of changes in the types of corals in the Bay from the delicate staghorns to more massive forms, coinciding with European settlement and possibly resulting from declining water quality as nearby catchments were altered.

These and many other aspects of the future of Australia’s corals will be explored at a scientific symposium and public forum in Brisbane this week.

The scientific symposium “Securing Coral Reef Futures” will take place on August 6 and 7 at the Brisbane Customs House.

It will be followed by the Public Forum on the future of the coral reefs worldwide at 6.00pm, Friday 7 August at the Brisbane Convention and Exhibition Centre. Media are welcome to attend both.

This and more from the scientific symposium “Securing Coral Reef Futures” here in Brisbane on the 6th and 7th August, including seminars by Dr Morgan Pratchett (adaptability of fish to ocean acidification and coral loss),Professor Garry Ryss (GBR Marine parks and fisheries stocks), and Professor Ove Hoegh-Guldberg (coral reefs, mangrove forests and global food security). Anyone is welcome to join the Public Forum on the future of the coral reefs worldwide at 6.00pm, Friday 7 August at the Brisbane Convention and Exhibition Centre (click here for more details).

“What will global warming look like? Scientists point to Australia”

Posted on April 9, 2009 by ovehblog

http://video.latimes.com/global/video/flash/widgets/WNVideoCanvas.swf

Los Angeles Times Online (April 9th 2008): They call Australia the Lucky Country, with good reason. Generations of hardy castoffs tamed the world’s driest inhabited continent, created a robust economy and cultivated an image of irresistibly resilient people who can’t be held down. Australia exports itself as a place of captivating landscapes, brilliant sunshine, glittering beaches and an enviable lifestyle.

Look again. Climate scientists say Australia — beset by prolonged drought and deadly bush fires in the south, monsoon flooding and mosquito-borne fevers in the north, widespread wildlife decline, economic collapse in agriculture and killer heat waves — epitomizes the “accelerated climate crisis” that global warming models have forecast.

With few skeptics among them, Australians appear to be coming to an awakening: Adapt to a rapidly shifting climate, and soon. Scientists here warn that the experience of this island continent is an early cautionary tale for the rest of the world.” (Link to full article)

Demise of newly discovered Australian deep water reefs, 4000m below the oceans of Tasmania

Posted on January 18, 2009 by ovehblog

Using a submersible robot to penetrate depths of up to 4000m, a joint US-Australian team have reported some extraordinary organisms off the coast of Tasmania.

“Our sampling documented the deepest known Australian fauna, including a bizarre carnivorous sea squirt, sea spiders and giant sponges, and previously unknown marine communities dominated by gooseneck barnacles and millions of round, purple-spotted sea anemones”

However, a news report by the AFP suggests that even at 4km beneath the surface, there is cause for concern:

“Modern-day deep-water coral reefs were also found, however, there is strong evidence that this reef system is dying, with most reef-forming coral deeper than 1,300 metres newly dead,” he said.

Though close analysis of samples was still required, Thresher said modelling suggested ocean acidification could be responsible.

“If our analysis identifies this phenomenon as the cause of the reef system’s demise, then the impact we are seeing now below 1,300 metres might extend to the shallower portions of the deep-reefs over the next 50 years, threatening this entire community,” he said.

The lead researcher Dr Ron Thresher from CSIRO is blogging the voyage from the Research Vessel ‘Southern Surveyor’ in incredible detail, and is well worth a read.

The submersible vehicle "Jason" pictured on board the RV Southern Surveyor, exploring the deep reefs of the Tasman Fracture Zone, southern Australia.

Australian Climate Statement 2008

Posted on January 12, 2009 by ovehblog

The Australian Bureau of Meterology released the annual Australian climate statement for 2008 last week. Another warm year for Australia, 0.41°C above the standard 1961-90 average…

Overview

The mean annual temperature across Australia for 2008 was the 14th warmest on record (0.41°C above normal).
A warm year was recorded in most regions, apart from Queensland, northeast New South Wales and the Kimberley (Western Australia).
Above average annual rainfall was recorded across the Top End, eastern Queensland, northeast New South Wales and far west parts of Western Australia. Rainfall was average to below average in the remainder of the country.
Low rainfall over the southern Murray Darling Basin during 2008 further exacerbated the long dry spell in this region.

A warmer than average year
Data collected by the Bureau of Meteorology indicate that, overall, Australia’s annual mean temperature for 2008 was 0.41°C above the standard 1961-90 average, making it the nation’s 14th warmest year since comparable records began in 1910.

Most regions recorded a warm year overall, apart from Queensland, northeast New South Wales and the Kimberley. Particularly high temperatures were recorded across inland Western Australia and the Northern Territory in January, as well as western Victoria and southern South Australia in March, with a record-breaking heatwave during the first half of the month. Conversely, cool temperatures were recorded in southeast Australia during February and again in April, across most of the country in August, and across the southwest during November.

Australia’s mean temperature for 2008 was slightly lower than that recorded for the previous six years, partly due to a La Niña event that developed in late 2007 and continued into early 2008. Despite the cooling effect of La Niña, Australia has now recorded a warmer-than-average year for the past seven consecutive years. In line with the rest of the globe, Australia has experienced a background warming of about 0.9°C over the last Century.

On 16 December 2008, the World Meteorological Organization (WMO) indicated that the global mean temperature was also warmer than normal during 2008 (about 0.31°C above average), making 2008 the globe’s 10th warmest year on record. It is now 23 years since the globe has experienced a cooler than average year.

Will we leave the Great Barrier Reef for our children?

Posted on October 28, 2008 by ovehblog

Amidst the current policy debate in Australia on climate change is a surreal argument that policies that will destroy the Great Barrier Reef (GBR) are acceptable and economically rational. Ross Garnaut was alive to the damage to the GBR when saying Australia should initially aim for a global consensus to stabilise greenhouse gases in the atmosphere at 550 parts per million. Garnaut (2008a: 38) was brutally frank in his supplementary draft report:

“The 550 strategy would be expected to lead to the destruction of the Great Barrier Reef and other coral reefs.”

His final report does not shy away from this conclusion (Garnaut 2008b).

The Australian and Queensland governments have always silently avoided this point when explaining the costs and benefits of their climate policies. Neither has ever stated a stabilisation target for the rise in global temperatures or greenhouse gases. To do so would expose them to the criticism that their policies will not save the GBR or a host of other ecosystems.

Garnaut’s frank admission reflects the findings of research of the impacts of climate change to the GBR since mass coral bleaching occurred globally in 1998 and 2002. Rising sea temperatures and increasing acidity of the oceans due to our use of fossil fuels are now well-recognized as major threats to coral reefs and the marine ecosystem generally in coming decades.

Coral bleaching and partial recovery on Pelorus Island, GBR: (a) 1998; (b) 2002; and (c) 2004. Source: Schuttenberg H and Marshall P, A Reef Manager’s Guide to Coral Bleaching (GBRMPA, Townsville, 2006), p12.

In relation to coral bleaching the IPCC (2007b: 12) found that:

“Corals are vulnerable to thermal stress and have low adaptive capacity. Increases in sea surface temperature of about 1 to 3°C are projected to result in more frequent coral bleaching events and widespread mortality, unless there is thermal adaptation or acclimatisation by corals.”

The findings of the IPCC suggest that a rise of 1°C in mean global temperatures and, correspondingly, sea surface temperatures above pre-industrial levels is the maximum that should be aimed for if the global community wishes to protect coral reefs. The range of 1-3°C is the danger zone and 2°C is not safe. Supporting this conclusion Ove Hoegh-Guldberg and his colleagues concluded in a review of the likely impacts of climate change to the GBR edited by Johnson and Marshall (2007: 295):

“Successive studies of the potential impacts of thermal stress on coral reefs have supported the notion that coral dominated reefs are likely to largely disappear with a 2°C rise in sea temperature over the next 100 years. This, coupled with the additional vulnerability of coral reefs to high levels of acidification once the atmosphere reaches 500 parts per million [CO2], suggests that coral dominated reefs will be rare or non-existent in the near future.”

The IPCC’s (2007a: 826) best estimate of climate sensitivity found that stabilising greenhouse gases and aerosols at 350 parts per million carbon dioxide equivalents (ppm CO2-eq) would be expected to lead to a rise in mean global temperatures of 1°C, stabilising at 450 ppm CO2-eq will lead to a rise of 2°C, and stabilising at 550 ppm CO2-eq will lead to a rise of 3°C.

Continue reading →

Never Mind the Mohawk, Here’s the Mary River Turtle

Posted on September 27, 2008 by ovehblog

Sorry for the bad pun… These great images were captured by photographer Chris van Wyk in Queensland, Australia (the green ‘mohawk’ effect, remniscent of the British subculture of the early 1980’s is actually an ephiphytic turf algae growing on the shell and head of the turtle). The Mary River turtle (Elusor macrurus) is considered “endangered” under the Environment Protection and Biodiversity Conservation Act in Queensland, and is geographically limited to shallow slow moving waters in the Mary River and it’s tributaries. Not only is it one of Australia’s largest species of turtles (>50cm), it is the sole species in it’s genus, representing an incredibly old lineage of turtles that has since disappeared from Australia’s evolutionary history. As Queensland has been in one of the longest draughts in over a century, the Queensland government is intending on creating a dam in the Mary River, impacting upon the habitat of the Mary River turtle and a host of other rare and endangered native species such as the Queensland lungfish and the Murray River cod.

“Carr targets PM on logging”

Posted on September 23, 2008 by ovehblog

Sydney Morning Herald, 22nd September, 2008

THE fraught political battle over logging in native forests is set to be re-ignited with the former Labor premier Bob Carr writing to the Prime Minister and senior ministers arguing that protecting the forests is “fundamental” to fighting climate change.

In a letter to Mr Rudd, his Climate Change Minister, Penny Wong, the Environment Minister, Peter Garrett, and the Forestry Minister, Tony Burke, Mr Carr has joined leading conservationists who want to transform state and federal forest policies in NSW, Victoria and Tasmania to protect older forests and previously logged forests.

Citing research from the Australian National University that says Australia’s eucalypt forests could hold about three times more carbon than previously thought, Mr Carr argues that rethinking forest policy is vital if Australia is going to cut its greenhouse gas emissions. Keeping carbon dioxide locked up, or “sequestrated”, in the forests will not only slow Australia’s rising greenhouse gas emissions but prevent the extinction of native plants and animals, the letter argues.

“Protecting our existing native forests and other vegetation is therefore fundamental to meeting any emissions reduction target. In addition, previously logged natural forests, if allowed to continue growing, will realise their carbon sequestration potential,” Mr Carr writes in a letter also signed by Peggy Figgis, the vice- chairwoman of the International Union for the Conservation of Nature, and Rick Humphries, from Greening Australia.

Continue reading →

‘Disturbing’ drought report released

Posted on July 6, 2008 by ovehblog

ABC News, 6th July.

The Federal Government has released a report into the link between drought and climate change, which it says will trigger major review of drought policy.

The report is by the Bureau of Meteorology and the CSIRO and is the first of three commissioned by the Government.

The report warns that extreme conditions previously thought to occur once in every 20 to 25 years, could become as frequent as every one or two years.

Prime Minister Kevin Rudd has told ABC1’s Insiders the report paints a very disturbing picture about the future of droughts in Australia.

"When it comes to exceptional or extreme drought, exceptionally high temperatures, the historical assumption that this occurred once every 20 years has now been revised down to between every one and two years," he said. Continue reading →

Australian attitudes towards climate change: putting words into action.

Posted on April 16, 2008 by ovehblog

The Climate Institute’s Climate of the Nation has released a report that shows that the attitudes of Australians has shifted from 5 years ago and that climate change is a primary concern. What is curious is that the Rudd government hasn’t convinced us that real and effective action will be possible..

"Australian attitudes towards climate change have crystallised into solid support for action, new research shows. But, equally, there is widespread scepticism about the ability of major political parties to deliver the necessary action. The Climate Institute’s Climate of the Nation report details the attitudes of Australians since the November federal election.

"In the aftermath of the world’s first climate change election, public concern and hunger for action remains high," the institute’s chief executive John Connor said.

"The majority of Australians (52 per cent) are unable to discern between the two major parties on climate change, meaning political brand ownership of climate leadership remains up for grabs." (Read more)

Meanwhile, federal environment minister Peter Garrett has decided against a national levy on plastic bags, despite Victoria introducing a levy, and South Australia banning plastic bags from 2009

"What we’ve decided today is that there will not be a national mandated charge on plastic bags in checkouts but we do want to see increased action to reduce plastic bag use in the community," Mr Garrett said.

"We’ve identified the need for an urgent working group to be established between government and industry to look at making sure retailers are exploring all the options that they have in front of them to increase the use of the green recycle bags and to lessen the use of plastic bags."

South Australian Environment Minister Gail Gago said she was "deeply disappointed" there had not been national agreement to phase out plastic bags or introduce a charge, but her state would push ahead with a ban regardless.

"After six years of the council, we’re still unable to come to a nationally consistent approach," Ms Gago said. (Read more)

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