Deserts And Climate Change

Deserts are one of the most affected ecosystems by climate change. Most desert are likely to become more extreme due to the foreseen climate change, and any solutions will depend largely on the human management (Noble & Gitay, 1996). Deserts and semi-deserts are predicted to be one of the most responsive of the world’s ecosystem types under the current increase of carbon dioxide (CO2) in the atmosphere and related global climatic changes (Lioubimtseva, Elena, & Adams, 2004). According to many environmental models used for climate change forecasting, the climate change has a wide range of direct and indirect impacts on humans, animals, vegetation, and even sometimes on the future behavior of the climate change itself. However, in the spite of

According to Lioubimtseva, et al. (2004), deserts are formed where climatic factors exclude moisture-bearing weather systems. Desert and semi-desert ecosystems represent about one third of the land surface of the world with generally less than 120mm annual rainfall. Most deserts are located in the range of 20˚ and 40˚ latitude, where dry air is transported to the Earth’s surface through tenacious high-pressure cells. However, it is the balance between this air mass and other factors such as topography, continentality and sea currents that determine the climate (Noble & Gitay, 1996). No estimation available for the human population in extreme deserts, but, there are over 800 million people estimated in drylands, many of whom will be affected by climate change (Noble &

However, surprisingly, there are cases that show positive impact of climate change on desert regions. One good example is the recent greening of the Sahel, the ecoclimatic and biogeographic zone of transition in Africa between the Sahara desert to the north and the Sudanian savanna to the south. The Sahara is actually shrinking, with vegetation arising on land where there was nothing but sand and rocks before (Mueller, 2011). It suffered long periods of destructive droughts and starvations between the late 1960s and early 1990s. Satellite photos, taken between 1982 and 2002, exposed the extensive re-greening all over the Sahel (Mueller). Rainfall has largely increased in the Sahel region over the 1980s and 1990s (Olsson, Lennart, Eklundh & Ardö, 2005). While many studies explained the increase in vegetation as a result of ‘over-cultivation’, ‘overgrazing’, and excessive exploitation of wood fuel, other recent results from global models used to study climate change suggested a strong relation between sea surface temperature (SST) anomalies and rainfall in the Sahel (Olsson, et