On Thursday 22 October the British Ambassador to Finland, Dr Valerie Caton, met with the Finnish Minister of Environment, Paula Lehtomäaki to hand over a copy of the Hadley Centre 4 degree climate change map. British Ambassadors in over 40 key countries were asked give copies of the map to their host governments the same day to coincide with the lauch of the map by the Foreign Secretary, David Miliband, the Secretary of State for Energy and Climate Change, Ed Miliband and Professor John Beddington, the UK Government’s Chief Scientist at the Science Museum. The Map was designed to understand more about what the human impact of high-end climate change might be, and therefore what would happen if a successful agreement can not be reached, the map outlines some of the impacts that may occur if the global average temperature rises by 4 °C (7 °F) above the pre-industrial climate average. The map was produced by the Met Office Hadley Centre, but contains contributions from climate scientists from other institutions conducting the latest research on climate impacts.


The map illustrates how agricultural yields are expected to decrease for all major cereal crops in all major regions of production. The availability of water will be affected by melting of glaciers, particularly in areas such as the Indus basin and western China, where much of the river flow comes from melt water.  Population increases, combined with changes in river run off as a result of changes in rainfall patterns and increased temperatures, could mean that by 2080 significantly less water is available to approximately 1 billion people already living under water stress. For many areas of the world sea level rise, combined with the effect of storms, will threaten low lying coastal communities. There are often very dense populations living along coasts, as well as important infrastructure and high value agricultural land, which makes the impact of coastal flooding particularly severe. The intrusion of salt water on farming land, and the risk to lives of flooding events could affect millions of people world wide every year.

The impacts on the poster are frightening, and the list is not exhaustive.  However, the map represents a world where climate change has gone unmitigated, where we have continued to emit greenhouse gases at the rates we are today. If we continue to do this, then the likelihood of the planet warming by 4 °C (7 °F) increases, and as it does so the risk of these impacts being realised also increases. By taking strong and effective action to curb greenhouse gases emissions, it may be possible to limit this temperature rise to 2 °C (4 °F). Although this would still bring some adverse impacts, the risk of the very severest impacts, as shown in the Met Office Hadley Centre map, is significantly reduced.

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