After a nine-month period of silence, a new discussion has started on Climate Dialogue, an international blog on the science of climate change. Goal of the platform is to explore the full range of views currently held by scientists, by inviting experts with differing views on the topic to participate. This new discussion is about one of the most crucial subjects in climate science: climate sensitivity
The objective of Climate Dialogue is not to reach a consensus, but rather to stimulate the discussion and to make clear what the discussants agree or disagree on and why. The project is financed by the Dutch Ministry of Infrastructure and the Environment (IenM). This new discussion is about one of the most crucial subjects in climate science: climate sensitivity (i.e. the level of temperature increase following a doubling of the amount of carbon dioxide in the atmosphere).
In its last assessment report (AR5), the Intergovernmental Panel on Climate Change (IPCC) concluded that climate sensitivity is likely to occur between 1.5 °C and 4.5 °C; a range that has not changed since the first assessment report in 1990. In AR5, a ‘best estimate’ was not given because of 'a lack of agreement on values across assessed lines of evidence'. The value of climate sensitivity is very policy relevant, because a sensitive climate implies the necessity for (many) more climate policy measures than a stable climate would require.
We are very pleased that the following three well-known contributors to the general debate on climate sensitivity have agreed to participate in this Climate Dialogue: from the United Kingdom Dr James Annan and Dr Nic Lewis and from the United States Dr John Fasullo. Together they cover a wide range of views, which promises a very interesting discussion!