Talks must begin now on the world’s ‘carbon budget’, leading economist and expert on climate change Lord Stern has warned.
On Friday, the Intergovernmental Panel on Climate Change (IPCC) released its latest review on the science of climate change. For the first time, scientists estimated how much more carbon dioxide can be released into the environment by manmade processes before irreversible damage is done.
The report found that a 2C increase in global temperatures could be catastrophic, causing rising sea levels and extreme weather conditions.The IPCC said that in order to have a chance of keeping to less than 2C of warming, the total carbon emitted could not exceed 1,000 gigatons.
More than half of that amount has already been emitted. However, the report added that if other greenhouse gases were taken into account, the budget would be reduced to 820-880 gigatons.
This means humanity may have already used up two-thirds of the carbon “budget.” It is estimated that as much as 2,500 gigatons worth of carbon in fossil fuel reserves is still unused.
Summarising the IPCC’s findings, Lord Stern, the chair of the Grantham Research Institute on Climate Change and the Environment at the London School of Economics, said we must emit no more than 820-1,445 billion tonnes of carbon dioxide and other greenhouse gases before 2100.
“Given that the world is currently emitting about 50 billion tonnes of greenhouse gases in terms of carbon-dioxide-equivalent each year, this report implies that, even if we were to stay at current levels, we would exhaust the emissions budget within 15 to 25 years”, he said.
“If we continue to increase annual emissions, the budget will be depleted even sooner. That is why I think nations, cities, communities and companies will recognise the importance of these findings and will increase the urgency and scale of the emissions reductions that they are planning to undertake.
“Delay is dangerous because greenhouse gases are accumulating in the atmosphere and because we are locking in high-carbon infrastructure and capital.”
However, climate change deniers have argued that such efforts are unnecessary. Writing in the Telegraph, former chancellor Lord Lawson, the founder and chairman of anti-climate change lobby group the Global Warming Policy Foundation (GWPF), argued that decarbonising the global economy would be “an economic nonsense, which would condemn us to a wholly unnecessary fall in living standards.”
On Saturday, George Osborne said that he did not want the UK to be at the forefront of efforts to prevent climate change, as the it may mean pricing the country out of international energy markets.
However, Lord Stern said that efforts to cut carbon could be an opportunity, rather than a burden: “The transition to a low-carbon economy, led by private sector investment, in the context of sound public policy, will be full of opportunity, discovery, innovation and growth.”