Decision making under uncertainty – Climate sensitivity and 2 degree target

Posted by Mitsutsune Yamaguchi July 28, 2015 Special advisor to Research Institute of Innovative Technology for the Earth

Huge uncertainty in Equilibrium Climate Sensitivity

There remain huge uncertainties related to almost all aspects of climate change, including science, technology and economy.

  • We are not sure of the future impacts of climate change whether there exists a particular temperature increase level (threshold) above which our society cannot tolerate.
  • We are not sure whether and when unknown innovative technologies will emerge.
  • We are not sure of the cost of mitigation and adaptation.
  • We are not sure of the extent the global surface temperature will increase when the CO2 concentration will double.

The last one is the uncertainty of the equilibrium climate sensitivity (ECS), one of the most crucial uncertainties surrounding climate change...