Desert expansion predicted across Mediterranean region

Desert expansion predicted across Mediterranean region

Mediterranean ecosystems will change to a state unprecedented in the past 10 millennia unless temperature rises are held to within 1.5°C. In a new study, published in the journal Science, exploring different scenarios, under business as usual vast tracts of the region may turn into desert. Forests would invade the mountain areas, with wild vegetation replacing the better part of the transient forests in most of the Mediterranean basin. Even if emissions are held to the level of pledges put forward ahead of the Paris deal, the Mediterranean region would experience a “substantial” expansion of deserts. 

The most affected areas would include southern Spain, Portugal, the northern side of Morocco, Algeria and Tunisia, as well as a number of other regions such as Sicily, the southern part of Turkey and some parts of Syria. The authors of the study, Joel Guiot and Wolfgang Cramer, employed data models based on pollen cores from sediments as a baseline against which to compare predictions of future climate and vegetation under different scenarios. 

Only a 1.5°C warming scenario would allow Mediterranean ecosystems to remain within the variability of the Holocene, a period characterized by recurring precipitation deficits rather than temperature anomalies. Current vegetation and land-use systems would be likely to persist under a 1.5°C warming above preindustrial temperature levels. However, a 2°C warming, would produce ecosystems in the Mediterranean basin that have no analog in the past 10,000 years.