The headline on the press release for this final capstone report in the Fifth Assessment Report (AR5) series signals the IPCC intent: “Climate change threatens irreversible and dangerous impacts, but options exist to limit its effects.”
It must be incredibly challenging to strike the balance on these reports, not just between over- and under-selling the climate science but between compelling action and sowing the seeds for despair and inaction. With this latest report released overnight, the IPCC hasn’t skimped on the scientific warnings – with 95% certainty that climate change is human induced and the highest greenhouse gas concentrations in 800,000 years – but it has settled on a decidedly optimistic note.
“We have the means to limit climate change,” said long-serving IPCC chair Rajendra Pachauri. “The solutions are many and allow for continued economic and human development. All we need is the will to change, which we trust will be motivated by knowledge and an understanding of the science of climate change.”
Mitigation cost estimates vary, but the report concludes global economic growth would not be strongly affected. In business-as-usual scenarios, consumption – a proxy for economic growth – grows by 1.6% to 3% per year over the 21st century. Ambitious mitigation would reduce this by about 0.06% points – and that does not account for the benefits of reduced climate change nor the numerous co-benefits associated with improved human health, livelihoods and development.
Said Working Group III co-chair Youba Sokona, “compared to the imminent risk of irreversible climate change impacts, the risks of mitigation are manageable”
We’re not missing the technologies to transition to a low-carbon economy, “but what is lacking are appropriate policies and institutions”
UN Environment Program (UNEP) executive director Achim Steiner in particular pointed to the lack of adequate, large-scale financial incentives. That is starting to shift . Up to US$365 billion was invested in energy efficiency in 2012 and US$254 billion in the renewable energy sector.
In fact the Secretary-General's Climate Summit last month was far more a story of private sector leadership than government leadership. One sample: leading investors working with UNEP's Finance Initiative pledged to reduce the carbon footprint of their investment portfolios for US$100 billion and to measure and disclose the carbon footprint of a total US$500 billion.
Working Group II co-chair Vicente Barros repeated a key theme from their report last year, the key role of adaptation in decreasing risks.
“Adaptation is so important because it can be integrated with the pursuit of development, and can help prepare for the risks to which we are already committed by past emissions and existing infrastructure,” he said.
If the necessary action is not taken, UNEP estimates adaptation costs for Africa alone could reach US$50 billion per year by 2050.
Divestment was another notable theme at the UN summit, and was the editorial frame The Australian chose for its coverage of the IPCC report, viewing it largely as an existential threat to coal. The newspaper also reported India and the US had strongly blocked any mention of a set global “carbon budget” in the report, though Pachauri was less coy.
“We have little time before the window of opportunity to stay within 2C of warming closes. To keep a good chance of staying below 2C, and at manageable costs, our emissions should drop by 40 to 70% globally between 2010 and 2050, falling to zero or below by 2100. We have that opportunity, and the choice is in our hands,” he said.
Building on AR5 scenarios, UNEP will soon be launching its 2014 Emissions Gap Report, which focuses on the global carbon emissions budget for staying within the 2C limit while updating the near-term emissions gap situation.
The next round of UN climate talks is next month in Lima, Peru, which will chart the course for the negotiations through next year to the crunch meeting in Paris in December 2015. As noted by Christiana Figueres, executive secretary of the UN Framework Convention on Climate Change, the science now demands action.
“In its first assessment in 1990, the IPCC commented that observed temperature increases were ‘broadly consistent with predictions of climate models, but it is also of the same magnitude as natural climate variability’. The second assessment, in 1995, said: ‘Results indicate that the observed trend in global mean temperature over the past 100 years is unlikely to be entirely natural in origin.’
“In 2001, its third assessment reported: ‘There is new and stronger evidence that most of the warming observed over the last 50 years is attributable to human activities.’ By 2007, the consensus had reached ‘very high confidence’ – at least a 90% chance of being correct – in scientists’ understanding of how human activities are causing the world to become warmer.
“Today the 5th assessment puts that certainty at 95% – a level at which to not act collaboratively and in a timely manner would fly in the face of both reason and responsibility.”
