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No sign of emissions letting up as climate talks begin

Temperatures and sea level are rising faster than predicted, but it's our ever increasing greenhouse gas emissions that are the real worry
A deal limiting warming to 2 掳C seems like a tall task
A deal limiting warming to 2 掳C seems like a tall task
(Image: Osama Faisal/AP/PA)

FORGET the fire, it鈥檚 the smoke that matters. In the lead-up to the climate change summit in Doha, Qatar 鈥 which wraps up at the end of this week 鈥 study after study painted a grim picture of our future, from permafrost melting more quickly than predicted to sea level rising faster. The worst news, however, is that far from cutting our emissions, we are pumping more greenhouse gases into the atmosphere than ever.

The latest figures from the , released this week, show that global emissions have been growing at an average of 3 per cent each year since 2000. We are on course to emit 35.6 billion tonnes of carbon dioxide this year just from burning fossil fuels and producing cement 鈥 a 58 per cent increase on 1990 levels, and this doesn鈥檛 include another 3 billion tonnes or so of emissions from deforestation and other changes in land use ().

China, now the biggest emitter, is responsible for most of this growth. 鈥淚t鈥檚 a slow tsunami,鈥 says the head of the project, Pep Canadell of Australia鈥檚 national science institute CSIRO in Canberra. China鈥檚 emissions are expected to grow until at least 2030. Even if they do peak by then, the emissions of other developing nations, particularly India with its 1.2 billion people, may continue to climb. The World Resources Institute reported last month that , most in India and China.

So there is little prospect of global emissions peaking around 2020 鈥 which is what is needed to stop the world warming more than 2聽掳C. Limiting warming to 2聽掳C is still possible, but after decades of inaction, it would now take an unprecedented global effort to achieve it. 鈥淚f this is not forthcoming, 2聽掳C is beyond our grasp and even 4聽掳C begins to look challenging,鈥 says Kevin Anderson of the Tyndall Centre for Climate Change Research in Manchester, UK. Each year you don鈥檛 do anything, the challenge grows greater, he adds.

Some countries have pledged to cut their emissions, but even if all existing pledges were kept 鈥 which seems unlikely 鈥 , a report commissioned by the World Bank warned last month. If we carry on as we are, temperatures could rise more than 4聽掳C well before 2100, and more than 8聽掳C before 2150.

This is not even the worse-case scenario. Some studies suggest that the rise in temperature will be 4聽掳C by the 2070s. The simulations on which these projections are based do not include the possibility of vast amounts of carbon being released from melting permafrost and undersea hydrates. Last week, reports from NASA and the UN warned that permafrost is already melting fast and that there could be extensive losses by 2100.

At the moment, however, we are pumping such amounts of carbon into the atmosphere that even massive releases of carbon from natural sources will not make much of a difference. Estimates suggest they will only lead to a small amount of extra warming. Instead, the real threat is more subtle 鈥 it鈥檚 that the longer we delay cuts, the less difference they will make, because by the time our emissions start to fall, the land and oceans won鈥檛 be able to take in any more carbon and will begin releasing it.

Meanwhile, the consequences of the 0.8聽掳C warming that has already happened since pre-industrial times are becoming ever more apparent. Studies out last week confirmed that ice in Greenland and Antarctica is melting much faster than predicted, for instance. Global sea level has already risen about 20 centimetres, largely because of the , and this has undoubtedly increased the damage caused by storm surges such as that of superstorm Sandy.

Topics: Climate change / Energy and fuels / Environment