The velocity of climate change

A race against climate change In the event of climate change, species have to move if they are to remain in an area with the same average temperature: their chances of survival therefore depend on the ability to keep pace with a moving climate as well as on the extent of change in temperature and other climate factors. To put this pressure on species into context, a novel index designed to quantify climate change in the coming century has been developed. Its value gives the local velocity along the Earth's surface needed to maintain constant temperatures, and is derived from temperature gradients scaled by distance (°C per km) and time (°C per year). The index provides a quantitative view of the role of topography in buffering climate change as it would affect plants and animals: on the IPCC's A1B emission scenario the index has a global mean of 0.42 km per year, compared to extremes of 0.08 and 1.26 km per year for mountains forest biomes and flooded grasslands, respectively. Climate change velocity, it turns out, is large relative to species migration speeds and the sizes of protected habitats. The data suggest that, in some ecosystems, helping species to relocate more rapidly via habitat corridors or new reserves could be an important contribution to conservation.