Is it too late to stop dangerous climate change?

Mike Childs

20 September 2011

It's almost 20 years since world leaders at the Rio Earth Summit agreed to take action to prevent dangerous climate change. Since then global greenhouse gas emissions have continued to climb. At the same time, scientists have suggested that temperatures need to be pegged at a lower level than previously thought if dangerous tipping points - such as the irreversible melting of the Greenland ice sheet or the release of vast quantities of methane from Siberian permafrost - are to be avoided. Even though I'm an incurable optimist it does make me ask myself the unavoidable question - is it now too late to stop dangerous climate change?

This is the question that has inspired Friends of the Earth to undertake a year-long research project that concludes today with the publication of the final two out of three research reports.

The first report considered the latest science findings, concluded that global temperature increases must be kept below 1.5 degrees to avoid the most devastating effects of climate change, and identified what this means for future emissions. It found that the EU would need to reduce its emissions by 60% by 2020 from 1990 levels, the United States would need to make even deeper cuts and China would need to peak its emissions by 2013 and then reduce them by 5% per year. These are clearly eye-watering reduction targets.

The second report used an adapted DECC 2050 pathways model to see if it's possible for the UK to live within its share of remaining emissions space - what we call a carbon budget. It also considered whether it was possible to do so in a socially just way. It concluded that even with Herculean efforts across all sectors the UK cannot meet its reduction goals without deploying technologies that take carbon out of the air, so-called negative emissions technologies. It did however conclude that reductions could be made without disproportionate impact on poorer households - although it would require a very determined effort to do so.

The final report is a technical analysis of the different potential negative emissions technologies currently being researched. It found that many of the technologies are at a very early stage of development, some bring significant risks, and that the most promising technologies are likely to be extremely expensive - certainly far more costly than action to reduce carbon emissions in the first place. It also found practical limits to the contribution that negative emissions technologies can make - at best, they can only provide a supporting role to emissions reductions. It concluded that dangerous climate change can only be averted if much-accelerated carbon emissions reductions are made across the globe in addition to negative emissions.

So the good news is that it's not yet too late to stop dangerous climate change. Phew.

The bad news is that it can only be done with much greater efforts by world leaders to speedily cut emissions. They promised action almost 20 years ago at the first Rio Earth Summit. They need to decisive action soon otherwise it will be too late. We and others will be keeping up the pressure on them to do so ahead of the Rio+20 Conference next June.

We are grateful to the Anthony Rae Foundation, the Joseph Rowntree Foundation and Zennstrom Philanthropies for their financial support for this research programme.