'Unrecognisable planet' by 2100
Global temperatures could increase by up to six degrees by the end of the century as worldwide carbon emissions continue to grow.PT1M39S http://www.canberratimes.com.au/action/externalEmbeddedPlayer?id=d-2aq9b 620 349 December 3, 2012
THE world is on track to see "an unrecognisable planet" that is between 4 and 6 degrees hotter by the end of this century, according to new data on greenhouse gas emissions.
As United Nations climate negotiations enter their second week in Doha, Qatar, an Australian-based international research effort that tracks greenhouse gas output will release its annual findings on Monday, showing emissions climbing too quickly to stave off the effects of dangerous climate change.
The new forecast does not include recent revelations about the effects of thawing permafrost, which is starting to release large amounts of methane from the Arctic. This process makes cutting human emissions of fossil fuels even more urgent, scientists say.
"Unrecognisable" ... the planet may get up to 6 degrees warmer by the end of the century. Photo: Paul Jones
The new data from the Global Carbon Project found greenhouse gas emissions are expected to have risen 2.6 per cent by the end of this year, on top of a 3 per cent rise in 2011. Since 1990, the reference year for the Kyoto Protocol, emissions have increased 54 per cent.
It means that the goal of the Doha talks – to hold global temperature rise to 2 degrees – is almost out of reach. That goal requires that emissions peak now and start falling significantly within eight years.
"Unless we change current emissions trends, this year is set to reach 36 billion tonnes of carbon dioxide from the combustion of fossil fuels, we are on the way to an unrecognisable planet of 4 to 6 degrees warmer by the end of this century," said the executive director of the Global Carbon Project, Dr Pep Canadell.
The big thaw ... Melting Arctic permafrost. Photo: Supplied
"Unless the negotiators in Doha wake up tomorrow and embrace a new green industrial revolution to rapidly change our energy systems, chances to stay below global warming of 2 degrees Celsius are vanishing very fast, if they are not already gone."
Emissions are growing in line with the most extreme climate models used by the Intergovernmental Panel on Climate Change, according to a paper in the journal Nature Climate Change that explains the Global Carbon Project's findings.
The trajectory means a temperature range of between 3.5 and 6.2 degrees by the year 2100, with a "most likely" range of between 4.2 and 5 degrees.
Although the climate has changed due to natural influences in the past, human emissions superimposed on top of natural variation is now driving change 20 times faster, according to NASA estimates. Civilisation evolved in a more moderate environment.
The new data is beginning to confirm what scientists had been warning people about for decades, said Andy Pitman, director of the Centre of Excellence for Climate System Science at the University of NSW.
"There are papers that should come with a warning: 'do not read this if you are depressed', or 'please have a stiff drink handy as you read this'. [This] paper is one such example," Professor Pitman said.
The greenhouse gas emissions path the world is taking "is not a tenable future for the planet – we cannot be that stupid as a species," he said.
Matthew England, a colleague of Professor Pitman and fellow author of Intergovernmental Panel on Climate Change reports, said: "While the science is clear that emissions reductions are required urgently, each year we are emitting more and more greenhouse gases into the atmosphere. This is like a smoker ramping up the number of cigarettes smoked each day despite grave warnings to stop smoking altogether – sooner or later this catches up with you."