Climate velocity

This technical term suddenly started to appear in non-specialist publications as a direct result of a paper by a group of US scientists that appeared in Nature on 24 December.

As the world warms, plants and animals unable to cope with rises in average temperature will have to migrate towards the poles if they are to remain in a climate belt to which they are adapted. This happened after the last Ice Age, when the northern edge of forests in Europe is thought to have moved north by about a kilometre a year. This rate of movement is the climate velocity, also called the temperature velocity. The research group calculates that a rate of about 0.4 kilometres a year will be needed to keep pace with the predicted change in our current climate.

One big worry is that there may be no suitable habitat for species to move into, as a result of human activity. Another is that many plants will not be able to migrate that fast. The research group suggested that human intervention may be needed if vulnerable species are not to die out.

Nevertheless, while the climate-velocity concept is still crude, it’s promising enough that Ackerly is collaborating with an organization called the Bay Area Open Space Council on habitat conservation strategies in central California.

Time, 24 Dec. 2009.

The scientists say that global warming will cause temperatures to change so rapidly that almost a third of the globe could see climate velocities higher than even the most optimistic estimates of plant migration speeds.

Guardian, 24 Dec. 2009.