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Is Climate Change Turning Africa's Deserts Green Again?

How Corporate Greed is Inadvertently Saving The Sahel!




Desert greening is substantially a function of water availability. If sufficient water for irrigation is at hand, any hot, cold, sandy or rocky desert can be greened. Because of changing weather patterns including a pronounced African typhoon season the vast expanse of deserts is turning green. It's one example of something that climate science says is necessary: Tackling climate change involves not only moving away from fossil fuels and eliminating CO2 emissions. Carbon removal through technology and natural solutions like planting trees the way East African countries have been doing for years is essential and will have to massively grow for the world to limit global warming now Saudi Arabia has joined the effort to replant deserts.


Although most of Saudi Arabia’s terrain is desert, the kingdom is “greening” its landscape by introducing various new technologies, changing its farming practices, and increasing the amount of vegetation under the Saudi Green Initiative (SGI). “Saudi Green Initiative aims to rehabilitate 40 million hectares of land and restore the natural greenery, with the target of planting 10 billion trees,” says Saule Mussurova, an academic researcher in Plant Science at King Abdullah University of Science and Technology (KAUST).“The project addresses this target by unifying factors such as water availability, climate, topography, soil moisture, and plant habitats,” adds Mussurova.


A comprehensive list of vegetation and tried-and-true planting methods is compiled to ensure optimum and sustainable ecological succession. The approach is to create a landscape strategy considering global, regional, local, rural, and urban contexts. This makes sense considering that if Saudi Arabia is unable to reverse its direction most of the cities will be too hot for human life before the end of the century without air conditioning and daylight curfews!


At present, we are in a dry period, but it is expected that the Sahara will become green again in in this century since Climate Change is on course if we don't stop using fossil fuels to advance the earths climate change clock by at least15,000 years. The greening of the Sahara, associated with the African Humid Period (AHP) between ca. 14,500 and 5,000 y ago, is arguably the largest climate-induced environmental change in the Holocene; it is usually explained by the strengthening and northward expansion of the African monsoon in response to orbital forcing. Now that is occurring because of the destruction of the ozone layer. China and the West are ushering in the greening of Africa again!


By adding more green cover, the estimate is that more carbon will be sequestered by plants. This should help mitigate the amount of carbon dioxide in the Earth's atmosphere, thereby decreasing global warming effects. Plants also help modulate climatic conditions in the region where they grow. Africa is also a land mass with higher elevation than other continents so flooding will not be as impactful as it will and is currently in Europe, North America, Australia, Asia, South Pacific and the Caribbean.


Between 1982 and 2020, leaf cover on plants rose by 21 percent in arid areas, excluding the southwestern United States, and Australia's Outback which has only seen 11 percent growth, yet many parts of Africa, the study found have seen massive greening due to the increase in water availability from increased storm seasons . The results were published in the journal Geophysical Research Letters.


The research confirms a long-held suspicion that one of the side effects of global warming will be lusher plant life. Plants pull carbon dioxide from the air — the gas is part of a chemical process called photosynthesis that plants use to make food. More carbon dioxide should lead to an average increase in vegetation across the globe, which studies have found in recent decades. But increased rainfall or changing temperatures could also be responsible for the new growth. But increasing carbon dioxide levels may do more than add more leaves to plants, lead study author Randall Donohue of the Commonwealth Scientific and Industrial Research Organization in Canberra said in a statement.


The carbon dioxide fertilization effect could shift the types of vegetation that dominate arid regions, he said. "Trees are reinvading grasslands, and this could quite possibly be related to the carbon dioxide effect," Donohue said. "Long lived woody plants are deep rooted and are likely to benefit more than grasses from an increase in carbon dioxide." Even though a bump in carbon dioxide can boost plant growth, the climate changes that come with growing concentrations of the greenhouse gas have caused concern. For example, plants also need the right amount of moisture, and changing rainfall patterns sparked by global warming could counteract the positive effects of additional carbon dioxide. Meaning places that are green now could become deserts and places that are deserts are seeing an increase inn greening!


The people living in the Sahel, a semiarid area just south of the Sahara desert, spanning the entire African continent from the Atlantic Ocean to the Red Sea, were suffering from several devastating droughts and famines between the late 1960s and the early 1990s. The draughts were triggered by decreases in rainfall from the early 1950s to the mid-1980s. Global warming was supposed to increase the frequency and severity of the droughts, which would make crop-growing unviable and cause even worse famines. According to the United Nations, the outlook for the people in the Sahel was bleak. But ironically the greed of multinational corporations has saved the Sahel and things are improving every year!


However in sharp contrast to this gloomy outlook, it seems that global warming has exactly the opposite effect on the Sahara and the Sahel. The Sahara is actually shrinking, with vegetation arising on land where there was nothing but sand and rocks before. The southern border of the Sahara has been retreating since the early 1980s, making farming viable again in what were some of the most arid parts of Africa. There has been a spectacular regeneration of vegetation in northern Burkina Faso, which was devastated by drought and advancing deserts 20 years ago.


It is now growing so much greener that families who fled to wetter coastal regions are starting to come back. There are now more trees, more grassland for livestock and a 70% increase in yields of local cereals such sorghum and millet in recent years. Vegetation has also increased significantly in the past 15 years in southern Mauritania, north-western Niger, central Chad, much of Sudan and parts of Eritrea. In Burkina Faso and Mali, production of millet rose by 55 percent and 35 percent, respectively, since 1980. Satellite photos, taken between 1982 and 2002, revealed the extensive re-greening throughout the Sahel.

Aerial photographs and interviews with local people have confirmed the increase in vegetation.

The main reason for the greening of the Sahara and the Sahel has been an increase in rainfall since the mid-1980s. Of the 40 rainfall stations across the ahel, most of them have been observing an increase in rainfall. If sustained, the increasing rainfalls could revitalize drought-ravaged regions,

reclaiming them for farming. The United Nations’ Africa Report of 2008 confirmed that the greening of the Sahel is now well established and that increases in rainfall are the main driver of the change in the vegetation cover.


The report noted that there was a 50% increase in vegetation in parts of Mali, Mauritania and

Chad during 1982-2003.12 Vegetation changes play a significant role in the rainfall variability.13 The increase in rainfall has allowed more plants to grow, which in turn increases precipitation even more. Plants transfer moisture from the soil into the air by evaporation from their leaves and hold water in the soil close to the surface, where it can also evaporate. The darker surface of plants compared with sand also absorb more solar radiation, which can create

convection and turbulence in the atmosphere which might create rainfall.


Vegetation effects account for around 30 percent of annual rainfall variation in the Sahel.14 The increased vegetation will fix the soil, enhance its anti-wind erosion ability, reduce the possibility of released dust and consequently cause a decline in the numbers of sand-dust storms. However, the greening cannot be explained solely by the increase in rainfall.


There were vegetation increases in areas where rainfall was decreasing, suggesting another factor was responsible for the greening in these areas. This other factor might have been the rise of atmospheric CO2 levels. The aerial fertilization effect of the ongoing rise in the air’s CO2 concentration increases greatly the productivity of plants. The more CO2 there is in the air,

the better plants grow. Rising atmospheric CO2 levels also have an anti=transpiration effect, which enhances the water-use efficiency of plants and enables them to grow in areas that were once too dry for them.


A study by Reindert Haarsma and his colleagues of the Royal Netherlands Meteorological Institute, which is based on a climate model, suggests that the increase in rainfall was triggered by an increase in surface temperatures in the Sahara. Haarsma et al argue that the Sahara heats up faster than the Atlantic Ocean, which creates lower atmospheric pressure above the desert. This leads to air with more moisture moving in from the Atlantic and more rainfall over the Sahel. According to Haarsma’s climate model, higher temperatures over the Sahara would cause 1-2 inches of extra daily rainfall in the Sahel during the months of July to September by 2080, which would be 45 to 80 percent more rainfall that fell in the drought ridden region in 1980.


There are other possible explanations. Recent climate modelling suggests a strong link between sea surface temperature anomalies and rainfall in the Sahel. Using a global circulation model and a number of sea surface temperature scenarios, Giannini et al were able to reproduce much of the observed rainfall variation in the Sahel between 1930 and 2000. Their study might explain 25-30 percent of inter-annual rainfall variations. James Hurrell of the U.S. National Centre for Atmospheric Research and Martin Hoerling of the U.S. National Oceanic and Atmospheric Administration claim that the increase in rainfall is linked to temperature changes in the Atlantic Ocean and is partially caused by greenhouse gas emissions. They drew this conclusion after analyzing 60 computer models that imitate the climate.

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