- The impact of temperature rises
ALMOST nine out of 10 climate scientists do not believe political efforts to restrict global warming to 2 degrees will succeed, according to a British poll. An average rise of 4-5 degrees by the end of this century is more likely, they say, given soaring carbon emissions and political constraints.
Such a change would disrupt food and water supplies, exterminate thousands of species of plants and animals and trigger massive sea level rises that would swamp the homes of hundreds of millions of people.
The poll exposes a widening gulf between political rhetoric and scientific opinions on climate change. While policymakers and campaigners focus on the 2 degree target, 86 per cent of the experts told the survey they did not think it would be achieved.
A continued focus on an unrealistic 2-degree rise could even undermine essential efforts to adapt to inevitable higher temperature rises in the coming decades, they warned.
The survey follows a conference last month in Copenhagen, where studies were presented that suggested global warming could strike harder and faster than realised.
All 1756 people who registered to attend the conference were contacted and asked for their opinions on the likely course of global warming.
Of 261 experts who responded, 200 were researchers in climate science and related fields. The rest were drawn from industry or worked in areas such as economics and social and political science. They included dozens of senior figures, including laboratory directors, heads of university departments and authors of the 2007 report from the Intergovernmental Panel on Climate Change.
The poll asked whether the 2-degree target could still be achieved, and whether they thought that it would be met: 60 per cent of respondents argued that, in theory, it was still technically and economically possible to meet the target, which represents an average global warming of 2 degrees since the industrial revolution (the world has already warmed by about 0.8 degrees since then). But 39 per cent said the 2-degree target was impossible.
The poll comes as UN negotiations gather pace in advance of a key meeting in Copenhagen in December, where officials will try to agree to a successor to the Kyoto protocol. The 2-degree target is unlikely to feature in a new treaty, but most of the carbon cuts proposed for rich countries are based on it.
Asked what temperature rise was most likely, 84 of the 182 specialists who answered the question said it would reach 3-4 degrees by the end of the century; 47 suggested a rise of 2-3 degrees, while a handful said 6 degrees or more. While 24 experts predicted a catastrophic rise of 4-5 degrees, just 18 thought it would stay at 2 degrees or under.
Some of those surveyed who said the 2-degree target would be met confessed they did so more out of hope than belief. "As a mother of young children I choose to believe this, and work hard towards it," one said.
Many of the experts stressed that an inability to hit the 2-degree target did not mean that efforts to tackle global warming should be abandoned, but that the emphasis was now on damage limitation.