“All of society must be on board” to limit warming to less than 2 degrees, IPCC chief warns
Governments and businesses must work together to take rapid steps to slash rising greenhouse gas emissions in order to prevent dangerous climate change, by investing billions of dollar in low carbon sources of energy, transport, and energy efficiency.
That was the call from scientists on the UN-backed Intergovernmental Panel on Climate Change (IPCC) yesterday, as they warned that delaying action to cut emissions until after 2030 will make it much more difficult and expensive to limit temperature rises to below two degrees Celcius by 2100.
Under a business-as-usual scenario, the world can expect to see temperature rises of three to five degrees by the end of the century, resulting in dangerous levels of climate change, the report warned. It said that effective mitigation measures would only be achieved if governments worked together on a global solution, rather than following narrow national interests.
"The high-speed mitigation train would need to leave the station soon and all of global society will have to get on board," Rajendra Pachauri, chairman of the IPCC told reporters at the report launch in Berlin. "So if we really want to bring about the limitation of temperature increases to no more than two degrees, then this is the message that comes out very clearly."
The summary for policymakers predicts that ambitious mitigation efforts would reduce economic growth by around 0.06 percentage points per year compared to a business-as-usual scenario of 1.6 per cent to three per cent annual growth.
Pete Smith, co-ordinating lead author for the Agriculture, Forestry and Other Land Use chapter of the report, said the cost of decarbonisation would be equivalent to delaying expected growth rates by one or two years in the middle of the century.
For the UK, this could mean 97 per cent of the projected economic growth being delivered by the middle of the decade.
However, the IPCC's calculations did not take account of the widespread associated economic benefits associated with cutting emissions and avoiding catastrophic climate change, including better air quality, higher energy security, improved human health, and fewer environmental costs. As a result, many economists are confident that decarbonisation would deliver net economic benefits, while others have warned that any attempt to model the economic costs and benefits associated with climate change and decarbonisation is likely to be fraught with difficulties.
Ottmar Edenhofer, co-chair of the IPCC's working group III which wrote the report, said the study showed "it does not cost the world to save the planet".
"Climate policy is not a free lunch but it could be a lunch worth buying," he added.
The report argued that in order to have a good chance of limiting global temperature rises to below 2 degrees, greenhouse gas emissions need to be cut by 40 to 70 per cent compared to 2010 levels by 2050 and then virtually eliminated by 2100.
This would require a tripling or even quadrupling of investment in low carbon energy sources, such as wind, nuclear, solar, carbon capture and storage, and the interim use of gas as a "bridging technology" to replace coal over the next few decades before being phased out or married with effective carbon capture technology.
The report also argued that this massive increase in clean energy needs to be accompanied by a 20 per cent reduction in investment in conventional fossil fuel plants by 2030 - a scenario that would have major implications for the valuations of fossil fuel assets.
The IPCC said annual investment in fossil fuels would need to decline to $30bn compared to 2010, while investment in renewables, nuclear and carbon capture and storage would near to soar by about $147bn. Annual investments in energy efficient transport, buildings, and industry would also need to increase by about $336bn over the same period.
The report comes just months before world leaders are due to meet at the UN-Secretary General's climate summit in September, where they will be expected to put forward climate mitigation and finance pledges in anticipation of a global deal on climate change being achieved in 2015 that would then come into effect in 2020.
The IPCC warned that the current pledges made in 2010 at the UN's Cancun climate summit would not be enough to put the world on a two degree pathway, but would instead likely result in at least three degrees of warming by the end of the century.
"So while we have not done enough to hit the two degree target that has been set, we have an opportunity to do a lot more," said Pachauri.
Commenting on the findings, Celine Herweijer, partner of sustainability and climate change at global consultancy giant PricewaterhouseCooper, said the report demonstrated that the costs of mitigation will become more expensive the longer governments and businesses delay action.
"Complacency in responding will see us head to a world of 4C or more of warming by the end of this century a world where business, economic and ecosystems survival cannot be assumed," she said. "Fundamentally, the latest IPCC reports show that not only are the costs to act affordable if we do so early, but that we all lose if we fail to respond adequately. Uncertainties due to a handful of nascent economic models are not excuses for inaction. Policy-makers and business leaders have a mandate to act under the weight of the evidence at hand. This evidence suggests urgent and bold action is a must at the national and international level."
However, Lord Stern, author of the influential Stern Review on the economics of climate change and head of the Grantham Institute on Climate Change at the LSE, said that by failing to fully address the costs associated with unmitigated climate change the report risked underplaying the urgent need to decarbonise the global economy. Reports suggested there had been tense negotiations about the final wording of the IPCC document, with industrialised economies blocking references for the need to subsidise clean energy investment in developing countries and petro-states said to be opposed to criticism of fossil fuel subsidies.
Stern predicted one to three per cent of global GDP would need to be invested annually during the next four to five decades to deliver a 50-50 chance of avoiding global warming of more than two degrees.
"This report should have provided a much stronger warning about the dangers of delay and much clearer about the immense risks from unmanaged climate change," he said. "To achieve the transition to low-carbon growth, we need sound policies, such as a strong price on carbon, and much more investments in technologies to reduce emissions, including electricity storage, renewables, nuclear power, and carbon capture and storage. The transition to sustainable low-carbon economic development and growth is an opportunity not just to avoid potentially catastrophic climate risks, but also to reap other benefits from cleaner and more efficient technologies, such as reductions in local air pollution."
However, if the report risks under-emphasising the scale and the urgency with which low carbon investment needs to be mobilised, it does make clear that investment needs to happen now and will only benefit the global economy if it is delivered. The message to investors, entrepreneurs, business leaders, and policy makers is clear: a low carbon economy powered by clean technology is affordable, desirable, and feasible. Thousands of businesses and millions of people around the world are already committed to delivering it, now is the time for the rest of the global economy to join them.