Copenhagen Accord puts world on pathway to 3ºC

German scientists have added up the emissions reductions pledged in the Copenhagen Accord and calculate that they put the planet on a pathway that misses the Accord’s stated 2ºC target, and only delivers a 50/50 chance of coming in under 3ºC by the end of the century. In an opinion article in this week’s Nature, Copenhagen Accord pledges are paltry, Joeri Roelgj et al show how the current emissions commitments amount to little better than “business as usual”, and effectively mean that global emissions will have increased by 20% by 2020. The key points in the article are:

• Nations will probably meet only the lower ends of their emissions pledges in the absence of a binding international agreement
• Nations can bank an estimated 12 gigatonnes of CO₂ equivalents surplus allowances for use after 2012
• Land-use rules are likely to result in further allowance increases of 0.5 GtCO₂-eq per year
• Global emissions in 2020 could thus be up to 20% higher than today
• Current pledges mean a greater than 50% chance that warming will exceed 3°C by 2100
• If nations agree to halve emissions by 2050, there is still a 50% chance that warming will exceed 2°C and will almost certainly exceed 1.5°C

A lack of ambition now means that countries will face steep emissions cuts in future. Co-author Malte Meinshausen told the BBC:

In an ideal world, if you pull off every possible emission reduction from the year 2021 onwards, you can still get to get to 2C if you’re lucky. But it is like racing towards the cliff and hoping you stop just before it.

Commenting on the article, Andy Reisinger of VUW’s Climate Change Research Institute told the SMC:

“This analysis shows that it is imperative to substantially strengthen the emissions targets for 2020 as part of a strong international agreement if the world is to have a realistic chance of limiting warming to 2°C. We are no longer gambling the future of the planet — if we stick with current emissions targets we are folding our cards entirely and leaving it to our (and other people’s) kids to pay our accumulated debts.”

VUW’s Martin Manning points out that politicians need to be given the mandate to act decisively:

It is becoming increasingly obvious that dealing with climate change is something that needs to become driven by society more broadly. People need to consider how much of a problem we want to pass on to our grandchildren and tell politics and industry to act accordingly.

The BBC coverage is excellent, dramatically illustrating the lack of ambition in European targets. Reports also at the Herald & Stuff