Declining trees spell gloom for planet

Ben Cubby, ENVIRONMENT EDITOR

The Age, August 25, 2010

LESS rainfall and rising global temperatures are damaging one of the world's best guardians against climate change: trees.

A global study, published in the journal Science, shows that the amount of carbon dioxide being soaked up by the world's forests in the past decade has declined, reversing a 20-year trend.

It diminishes hopes that global warming can be seriously slowed down by the mass planting of trees in carbon sinks. Although plants generally grow bigger as a result of absorbing carbon-enriched air, they need more water and nutrients to do so, and they have been getting less.

A fierce drought that dried out vast areas of the Amazon Basin in 2005 is seen as a key to the global decline in carbon sinks in the past decade, but Australia is not immune.

''Australia is a significant contributor to the global pattern, and the findings are consistent to what we have seen here,'' said a senior CSIRO researcher and director of the Global Carbon Project, Dr Josep Canadell.

''There has been a measurable decline in the leaf area of plants this decade, though we don't have all the data for Australia yet. What we have seen is strongly consistent with projected patterns of climate change.''

The Science study, Drought-induced Reduction in Global Terrestrial Net Primary Production from 2000 through 2009, used data from a NASA satellite that orbits Earth every 15 days to build up a global map of changing leaf density and forest cover. It estimated net primary production, a measurement of how much CO2 is taken in by plants and stored as part of their biomass.

The study found that in some areas of the world, higher temperatures had driven more plant growth. But these gains have been cancelled out by drier conditions in rainforests, leading to the overall decline in total amount of CO2 the forests are soaking up.

The findings reinforce work being done at the Australian Bureau of Rural Sciences, which is researching how much carbon can be stored on a long-term basis in the landscape.

Scientists say that a sustained decline in the amount of carbon being stored in forests risks locking in a vicious cycle, in which trees absorb less carbon because the world is warmer and drier, while the rising carbon levels in the atmosphere continue to trap heat.

''There is no single silver bullet answer to this, but one of the partial solutions is the protection of old-growth forests, which store a lot of CO2, and the replanting of those that have been removed,'' said Professor Andy Pitman, the co-director of the Climate Change Research Centre at the University of NSW.

''This doesn't actually get to the heart of the problem though, which is rising CO2 emissions from human activity.''

Rainfall patterns in Australia are expected to alter significantly over the next few decades as average temperatures increase, with more rain likely to fall in the north and north-west and less precipitation likely in southern Australia. This means that many of Australia's existing old-growth forests, which are located in NSW, Victoria and Tasmania, can be expected to become less efficient carbon sinks.

Australian scientists take a stand on climate

Monday, 16 August 201

by Becky Crew

Cosmos Online, 16 August 2010

The Science of Climate Change, Questions and Answers, August 2010 can be viewed and downloaded here.

SYDNEY: Trying to set the record straight on climate change in the middle of a hotly contested national election, the Australian Academy of Science has taken a stance and produced a report that tackles the critics of the science.

"Climate change is not science fiction," said Suzanne Cory, president of the academy at a press conference in Canberra announcing the launch of their publication The Science of Climate Change: Questions and Answers.

It was written and reviewed by 16 of the country's foremost scientists across a range of disciplines, including oceanography, climatology, geology and physics.

Knowns and unknowns

In the booklet, the scientists highlight what is known with certainty, while "including a frank discussion on the uncertainty," added Cory.

The document, one of the clearest statements on climate change yet produced, is designed to be scientifically rigorous but aimed at general audience.

According to a statement by the academy, the document aims to "address confusion created by contradictory information in the public domain."

Politicians don't know what's safe

During the current election campaign, both the Labor government and the Liberal-National conservative coalition have sparred over climate change, with some politicians expressing doubts about the science.

A University of Queensland survey of more than 300 federal, state and local government politicians in Australia released in early August 2010 found that almost 70% of politicians believe human-induced climate change was occurring.

But it also found more than 40% thought a increase of 4˚C was 'safe' - despite scientific warnings that a global temperature increase of just 2˚C or more could be dangerous.

Widespread confusion

It also found widespread confusion about what climate change really meant: 75% believed the Great Barrier Reef is threatened by global warming, but only 55% agreed that ocean ecosystems were also threatened – even though the Great Barrier Reef is part of the ocean's ecosystems.

Written and produced over seven months, it was scheduled to be launched today as part of Australia's National Science Week – which now just happens to coincide with the last week of a federal election where climate has become a hot-button political issue.

It is based on extensive research into the records of the Earth's distant and recent past, climate models and the known physical principles of greenhouse gas, the document intends to explain the current situation, and outline where the questions and certainties lie in the scientific community.

2010: the year of the heat wave

With the global average temperature of the Earth's surface increasing over the last century, and greenhouse gases the proven cause, it is expected that global temperatures will continue to rise.

"2010 is becoming known as the year of the heat wave," said Neville Nicholls, president of the Australian Meteorological and Oceanographic Society. "With 17 countries having set new record hot temperatures."

"While 'one swallow does not a summer make, nor one fine day' a ratio of 17 new hot records to only a single new cold record is pretty convincing evidence that the world is warming. So this accessible summary of climate science, prepared by Australia's peak scientific body, is timely and welcome."

Two committees establish questions and answers

In an effort to contribute to the public understanding of the current state of climate change science, the Academy set up two committees of internationally recognised scientists to address the most important and commonly asked questions.

This involved the establishment of a working group of a number of the world's most eminent climate scientists to identify and answer the seven 'big' questions in most urgent need of answers.

An oversight committee consisting of highly regarded fellows of the academy and other climate experts then comprehensively reviewed the answers to ensure that they were consistent with the current and extensive research in the field.

Seven big questions

From the definition of climate change to its evolution and future consequences, the document aims to summarise and clarify the current understanding of the science of climate change for non-specialist, non-expert readers.

While acknowledging that there are still significant uncertainties in our current understanding of climate change, particularly in regards to future consequences, in answering the seven big questions it provides some fundamental, absolutely certain conclusions.

"The document acknowledges the significant uncertainties that surround our knowledge about how climate change will continue to unfold this century and beyond," said Will Steffen, executive director of the Climate Institute at the Australian National University in Canberra.

"But it makes absolutely clear that we know two critical aspects of climate change with a very high degree of certainty: climate change is indeed real and is already happening, and human emissions of greenhouse gases are the primary cause."

Climate change pushing fish south

By environment reporter Sarah Clarke

ABC News Online, 13 August 2010

A new CSIRO study has found that climate change is driving a widespread number of fish south as the oceans warm.

The study found around 30 per cent of Australia's inshore coastal fish families have been found outside their usual area.

CSIRO has identified south-eastern Australia as a climate change hotspot, with well documented changes already occurring over the last 70 years.

CSIRO spokesman Dr Peter Last says a snapshot of the distribution of coastal fish has located 43 types of fish outside their normal range.

Those species on the move include rock flathead, tiger sharks and Queensland gropers.

"We had a coral trout, for example, which is a common commercial fish from Queensland, as far south as Port Arthur," Dr Last said.

CSIRO National Fish Collection spokesman Alistair Hobday says the consequences are not always positive.

"These animals are going to move further south and they'll have nowhere else to go once they get to the tip of Tasmania," he said.

The study also found up to 19 species of Tasmanian coastal fish have undergone serious declines, and some are possibly extinct locally.

Mr Hobday says a number of warm temperate species have now colonised cooler areas, and some species may struggle to survive.

"What has been surprising to us is how widespread this movement has been and this paper for the first time shows how widespread that is," he said.

How to be fully renewable in 10 years

BEN CUBBY 

The Age, August 13, 2010

AUSTRALIA could switch completely to renewable energy within a decade by building a dozen vast, new solar power stations and about 6500 wind turbines, according to a major new study.

The Zero Carbon Australia Stationary Energy Plan - a collaboration between Melbourne University's Energy Research Institute, the environment group Beyond Zero Emissions and engineers Sinclair Knight Merz, puts the cost at $37 billion in private funding and public investment every year for the next decade.

The price tag may make it sound like a pipedream but the scheme earned the endorsement of the federal Liberal MP Malcolm Turnbull who added his support at a forum at Sydney Town Hall last night.

''The work they have done is important,'' Mr Turnbull said. ''It provides the most comprehensive technical blueprint yet for what our engineers, our scientists, can begin to do tomorrow.''

Mr Turnbull contrasted the Coalition's ''direct action'' plan with Labor's policy, which he claimed would lead to longer delays in cutting greenhouse gas emissions.

''I believe our long-term global goal is to very substantially reduce our emissions, a goal that will require almost all of our stationary energy to be produced from zero or near-zero emission sources,'' Mr Turnbull said.

''This report demonstrates we could already be technologically ready to do that.''

The plan has also been endorsed by Australia's former chief scientist Robin Batterham, and a senior official at the International Energy Agency's renewable energy division, Cedric Philibert.

However, the National Generators Forum, which represents power station owners, and the office of the federal Energy Minister, Martin Ferguson, were decidedly lukewarm about the plan when asked about the findings last month. Under the plan, 60 per cent of the nation's electricity would be sourced from 12 huge solar thermal power plants, which use Australian-developed technology to store heat in molten salt, allowing them to operate for long periods when there is no sunshine.

The remaining 40 per cent of the power grid would be filled by about 6500 wind turbines at 23 large-scale wind farms dotted mainly around the coast.

The plan would generate 325 terawatt hours of electricity a year, meeting the nation's entire power demands in the year 2020, if a comprehensive energy efficiency plan is also factored in. Any shortfalls could be made up by biomass energy generation, using a portion of the stubble from the nation's wheatfields.

To properly harness all the renewable energy, the report calls for the unification of Australia's three separate electricity grids and some new transmission lines to link the new power stations to capital cities, at a total cost of $92 billion.

If the cost of completely transforming the energy sector was passed directly on to households, it would add 30 per cent to the average utility bill.

Matthew Wright, the chief executive of the Beyond Zero Emissions group, claimed the report was more realistic than Australia's continued dependence on foreign oil supplies and fluctuating fuel prices.

''The fact is, from an energy perspective, we are in big trouble,'' said Mr Wright when he briefed staff from the NSW Department of Climate Change, Environment and Water on the plan yesterday.

''If you're going to secure Australia's energy future, then you're going to do that with risk-free renewable energy that has no fuel costs.''

Huge rise in sea levels forecast if global warming ignored

BEN CUBBY 

The Age, August 12, 2010

See also The Guardian 

Sea levels could rise by up to seven metres if greenhouse gas emissions were not scaled back, a panel of leading geoscientists has told the US Congress.

The warning came as a vast ice shelf, about 260 square kilometres in size, continued to fall away from Greenland's Petermann glacier, the largest iceberg shed by the island in half a century.

The geoscientists told Congress Greenland might cease to exist, with the island rapidly approaching a tipping point that would see much larger masses of ice melting, pushing up the average level of oceans around the world. Temperature rises of between two and seven degrees Celsius - which are considered likely by the end of the century due to human-induced carbon emissions - would force the change, they said.

A leading Australian sea level rise researcher, Dr John Church, broadly agreed with the US assessment. ''We are seeing something significant, and it's something our coastal cities have not experienced before,'' said Dr Church, a lead author of the most recent global assessment by the Intergovernmental Panel on Climate Change. ''We're beginning to move outside the range of what we have become used to seeing as normal variability, and see an acceleration of both greenhouse gas levels and sea level rise.''

But there was still a great deal of uncertainty about the timing and extent of the disintegration of Greenland's ice sheets, Dr Church said.

''We are looking at a process that will be going on for centuries,'' he said. ''It may be that we do cross that threshold relatively soon, but there is a lot of uncertainty around it, in my view.''

Professor Richard Alley, a geoscientist at Pennsylvania State University, told the US House of Representatives committee on energy independence and global warming a sea level rise of seven metres was a realistic possibility.

''Some time in the next decade we may pass that tipping point, which would put us warmer than temperatures that Greenland can survive,'' Professor Alley said.

The current threshold at which Greenland would melt is a temperature rise of between two and four degrees, according to the UN's current estimate.

The Australian government is currently planning for a sea level rise of 90 centimetres by the end of the century.

Dr Ryan McAllister, a scientist from the CSIRO's climate adaptation division, said planning for sea level rises needed to become more flexible to take uncertainty into account.

''We also need to broaden our perspective on planning so we can adapt to different stages of climate change as they emerge,'' Dr McAllister said.