April 15, 2014

IPCC WGIII Fifth Assessment Report: Investments and Cross Cutting Issues

The Fifth Assessment Report of the IPCC was approved on Sunday April 13th.

The Summary for Policy Makers is available here.

Not major findings in my opinion. Maybe, the most important part is on the 2°C temperature limit.

In a nutshell: we can keep global mean temperature below 2°C if 1) ALL countries start 2) NOW using 3) ALL technologies available (including CCS and nuclear) and accept to loose 1.7% (1.0% – 3.7%) of consumption in 2030, 3.4% (2.1% – 6.2%) nel 2050 and 4.8% (2.9% – 11.4%) in 2100. If we start late, costs increase quickly and many models show that the 2°C is not feasible. If we do not use CCS, costs increase by 138%. Not really new findings, but good to see the IPCC endorsing results in the serious literature.

In practice (this is my opinion, not the IPCC opinion), the 2°C is not attainable with present technologies, if we do not (quickly) collectively embrace the life of Saint Francis of Assisi. A few years ago Carlo Carraro and I wrote a column for Vox-EU titled "The improbable 2°C target" on why we should prepare for 2.5 or 3°C.

The Chapter for which I was Lead Author is on Investments and Cross Cutting Issues (Ch 16). For the first time the report provides estimates of investments in key mitigation technologies (See the Figure below for change of investments in 2010-2029).

There are not many studies in the literature with investment estimates. Carlo CarraroAlice Favero and I co-authored one of the few studies in the literature that estimates investments in mitigation technologies. You find a copy here. Hopefully the authors of the next report will have more observations to build more robust estimates.