No time to delay

Richard Chirgwin writes in The Register about a new study by IIASA in Austria about the significant cost increase if there are delays in mitigating GHG emissions.

Delay climate mitigation, escalate the costs: study

Costs would escalate five-fold in next seven years

Which would hurt less: a global carbon price of $US20 now, or a $US100 carbon price in 2020?

That’s the stark choice offered by a new study by the International Institute of Applied Systems Analysis in Austria, published in Nature (abstract here).

The paper, Probabilistic cost estimates for climate change mitigation, seeks to generate “distributions of the costs associated with limiting transient global temperature increase to below specific values,” the authors explain.

If agreement can’t be reached before 2030, the researchers say, a 2 degree C target will be out of reach, the authors told Reuters.

Even an immediate price of $US20 per tonne of CO₂ isn’t a guarantee of anything, the study’s authors explain: it only provides a 60 percent chance of keeping temperature rises to below 2°C.

The study, which also included researchers in Switzerland, New Zealand, Australia and Germany, found that the timing of greenhouse emission reduction is far more influential than any scientific uncertainty. And that means the politics is now far more important than anything that might pop up on denier blogs.

IIASA says if action is delayed, the outcome will include an urgent need to take coal-fired power generation offline.

If mitigation steps aren’t taken, the researchers say, global annual emissions by 2020 will reach 55 gigatons of CO₂ each year. At that point, IIASA’s Keywan Riahi says, “you would need to shut down a coal power plant each week for ten years if you still wanted to reach the two-degree Celsius target”.

“Fundamentally, it’s a question of how much society is willing to risk,” says IIASA energy researcher and a co-author of the study, David McCollum.