Based on current rates of carbon dioxide emissions and fossil fuel use, the Earth's temperature is set to increase in the long term by more than 6 degrees Celsius, the IEA warned in its World Energy Outlook 2011.
The maximum "safe" increase, according to most scientists, is 2 degrees Celsius. Above this point, climate change becomes "catastrophic and irreversible," according to the Guardian.
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If the world is to limit global warming to 2 degrees, it would have to begin permanently decreasing its consumption of fossil fuels from 2016 onwards, the IEA said. Meanwhile energy from alternative sources such as wind, wave, solar and nuclear would have to increase dramatically, as would energy efficiency.
IEA chief economist Fatih Birol told the Wall Street Journal:
"The door to reach two degrees is about to close. In 2017 it will be closed forever."
Even if countries deliver on all the pledges so far made to reduce emissions, the report said, the global temperature will still rise by 3.5 degrees Celsius, an increase that would trigger sea level rises, drought, floods and heat waves.
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Nothing in the IEA's analysis indicates that the kind of fundamental changes it is calling for will be delivered.
According to its figures, CO2 emissions rose by an "almost unprecedented" 5.3% in 2010. The biggest source of emissions growth was the use of coal, particularly in China and India.
Halting emissions increases would mean investing an extra $15.2 trillion in clean energy by 2035, the IEA estimates. Given the current financial situation, that committment would come as "a very big surprise," said Birol.
The IEA's warning comes shortly before the United Nations is due to start its next climate change conference in Durban, South Africa, at the end of November.
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