Interactions of desertification and climate in Africa

Much of the scientific literature dealing with interactions of desertification and climate is based upon hundreds of studies dealing with the African continent. Three decades ago, the severe drought in sub-Saharan Africa generated an extensive discussion of whether overgrazing and land degradation in the region had produced atmosphere/land surface feedbacks that exacerbated drought throughout the Sahel. Related studies focusing on the possibility of desertification producing warming trends in historical temperature records were also based on African data sets. Furthermore, evidence from southern Africa suggests that land degradation in drylands can lead to warmer afternoon temperatures and an increase in the diurnal temperature range; this finding is opposite of the decline in diurnal temperature range reported throughout most of the world. Many articles have appeared in the literature showing how variations in the climate system can impact drought conditions in Africa, and the linkages between sea surface conditions, atmospheric circulation, and precipitation patterns in Africa are reasonably well known thanks to this research. In most recent years, a substantial literature has developed regarding how anthropogenic greenhouse-induced climate changes could impact the African continent. Generally speaking, climate models suggest that a build-up of greenhouse gases in the atmosphere could lead to a warming of Africa, increased potential evapotranspiration rates, a reduction of soil moisture, and an increase in the frequency, intensity and magnitude of droughts. The countries of the world recognize the importance and potential threat of the desertification/climate change issue for Africa, and in response, the United Nations has developed an international convention to combat desertification, especially in Africa.