Since the 2015 Paris agreement, climate change at the targets of 1.5 and 2 °C of global warming since pre-industrial times are of increased interest and political relevance. However, projected changes in Australia specifically for these targets are not yet included in national or state climate projections for use in impact, adaptation and vulnerability assessments. As we prepare to report on changes in Australia under Paris targets for state and national climate projections, this talk will outline various issues involved in reporting on Paris, and aim to stimulate further discussion.

Some of the main issues to tackle regard the difference between the ambitious mitigation scenario of RCP2.6 that are already reported on, and the Paris targets specifically. Changes under RCP2.6 are not specific to a global warming target (more than 80% of models break 1.5 °C and more than 30% of climate models break the 2 °C target by 2100). Also, there are some specific features of meeting Paris targets that mean that a simple, low RCP is not analogous – such as a possible ‘overshoot’ then return to the target. Importantly for impact assessments, there are a range of policy settings that get us to the targets in terms of emissions, greenhouse gas removal and climate engineering. The difference between these settings may be just as important, than physical climate change at each target. There are also fewer and less coordinated climate model ensembles created for looking at Paris targets specifically, raising issues of comparability with other projections. These and various other issues will be discussed.