The scientific community is currently in the position that we know that the climate is changing, and that it is anthropogenic (IPCC WG I). We also know how to reduce emissions to limit global warming. Since it will be much more expensive to limit global warming to 2°C than 3°C or more (IPCC WG III), there have to be good reasons to justify the additional mitigation efforts.
However, despite progress with regard to impact model developments, our picture of the world at different levels of global warming is still vague. Human societies urgently need to understand how the climate will change in the future, what the related impacts for natural and social systems are, and what suitable strategies for adaptation and potential transitions towards a sustainable future could look like.
A major challenge for climate impact research is a lack of methods for aggregation, uncertainty analysis, and synthesis of climate impacts across regions, sectors, and scales. Moreover, changing frequencies in extreme events have to be taken into account. While there is a wide spectrum of region-specific and sector-specific case studies on climate impacts, vulnerabilities, and adaptation strategies, no clear global picture has yet emerged. Systematic long-term socio-economic impact modelling approaches still need to be developed, contributing to the PIK strategy of whole-system approaches towards climate impact research.
Figure: Regions worldwide where RD2 carries out impact studies