The mandate of the IPCC is to be neutral with respect to policy, so its assessment reports do not recommend any policies. This is different from scientific advisory bodies to governments, which are often asked to provide specific policy recommendations. Although this is sometimes misreported in the media, the IPCC does not recommend limiting global warming to a specific target (such as 2 °C) or stabilizing greenhouse gas concentrations at a certain level (such as 450 ppm). Likewise the IPCC does not recommend any mitigation options, such as renewable energy or nuclear power – the report merely lays out a range of available options and tries to evaluate how much they could reduce emissions and at what cost. The IPCC reports provide the scientific background information needed by policy makers and society at large to make well-informed decisions as to which policy they would like to follow. The IPCC mantra is to provide scientific information that is policy relevant, but not policy prescriptive.

But climate scientists are also citizens who care about the world, about their own future and that of their children and grandchildren, or about the fate of people living in other parts of the world affected by climate change. Many of us therefore follow the climate policy debate very closely, simply because climate change and its effects on human society are something we think about almost every day.