|Title||Does climate policy need probabilities?|
|Publication Type||Tyndall Working Paper|
|Series||Tyndall Centre Working Papers|
|Tyndall Consortium Institution|| |
|Secondary Title||Tyndall Centre Working Paper 34|
|Authors||Dessai, S., and M. Hulme|
|Year of Publication||2003|
Estimating the likelihood of future climate change has become a topical matter within the research community. This is the case because of the advancement of science, user demand and the central role played by prediction in guiding policy. But are probabilities what climate policy really needs? This paper reviews three key questions: (1) why might we need probabilities of climate change? (2) what are the problems in estimating probabilities? (3) how are researchers estimating probabilities? The first question is primarily analysed within the context of adaptation to climate change, but mitigation and integrated assessment are also briefly discussed. The second question explores the types and sources of uncertainties involved in estimating probabilities of climate change and how their characterisation can be controversial. For the third question, an extensive review of the literature is conducted on research that is creating the building blocks towards estimating the likelihood of climate change. Overall, we conclude that the jury is still out on whether probabilities are useful for climate policy. The answer is highly context dependent and thus is a function of the goals and motivation of the policy analysis, the unit of analysis, timescale and the training of the analyst. There are various problems in estimating the probability of future climate change, but human reflexive uncertainty is largely intractable in the context of prediction. Nonetheless, there is considerable scope to develop novel methodologies that combine conditional probabilities with scenarios and which are relevant for climate decision-making.