 Another set of normative issues arises from the fact that climate projections are characterised by risk and uncertainty. A comprehensive analysis of climate justice needs, then, to consider the just way to respond to risk and uncertainty. To underscore why this matters it is salutary to consider the IPCC’s Fifth Assessment Report. Suppose that we take the appropriate target to be avoiding an increase in global mean temperatures of more than 1.5°C when compared with pre-industrial times. The quantity of greenhouse gases that can be permissibly emitted varies enormously depending on how risk-averse we think that our approach should be. According to the IPCC a 33% probability of meeting the 1.5°C target results in a greenhouse gas budget of 840 GtCO2 whereas a 66% probability of meeting the same target results in a greenhouse budget of 420 GtCO2 (Rogelj, Shindell, &amp; Jiang 2019: 108). If we opt for the more risk averse approach, then, the volume of greenhouse gases than can be permissibly emitted is half the size that the budget would be if we opt for the less risk averse approach. One question that arises then is: How risk-averse should we be? How should policy-makers treat risk and uncertainty?