The greening of the Sahara and the Sahel is returning to how it was in Ancient Numidia as nations plant beneficial trees to speed the transition!
The ancient black country of Numidia in North Africa, corresponding roughly to present-day Algeria: flourished until its invasion by Vandals in 429 changing the population to the highly mixed one of Amizagh who because of their European lineage were never taught to read and write the ancient language of the true indigenous Numidians who retain their culture in its entirety today; The ancient Carthaginians intermixed with the native population of the Numidians and Mauritanians. Mauri (from which derives the English term "Moors" meaning "Blacks") was the Latin designation for the Berber population of Mauretania, located in Western North Africa on the shores of the Mediterranean Sea, Mauretania Tingitana and Mauretania Caesariensis, in present-day Morocco and northwestern Algeria.
(. chief towns were Cirta and Hippo Regius. During the Holocene Climate Optimum (9000-4000 BC), whose early and middle parts were possibly 2-5 degrees Celsius warmer than now exactly what is forecast because of international lack of concern by politicians over the effects of climate change, ironically the northern half of Africa and the Sahel received and are receiving more abundant and more stable rainfall. What is now the Sahara desert was a green savannah then.
Rock paintings from what was once Numidia the ancient African kingdom of the Numidians famous for their cavalry located in northwest Africa, comprising the territory of Algeria, Tunisia, Libya, and some parts of Morocco. The art from this period show brown skinned Numidians and savannah animals such as elephants and zebus (cattle). Bones of crocodiles and hippos were found in the Sahara together with sediments showing that big lakes and rivers existed there until 6,000 years ago.
Experts in paleoclimate think that the Sahara’s climate is twisted between two extremes: it is either wet enough to create and sustain a green savannah or it does not support vegetation. They claim that there is threshold to be crossed to get from one extreme to the other. Scientists have shown that, when the greening first starts due to some more rainfall, vegetation itself influences the climate, producing even more rainfall. In the Holocene, says Professor Peter de Menocal of Columbia University, first the greening and then the desertification of the Sahara might have been a matter of a century!
The Sahel is greening may have taken only decades. This indicates that the increasing precipitation could quickly green the Sahel. There were earlier examples of a “green Sahara”. North African climate reconstructions have revealed three periods during which the Sahara was almost completely covered with extensive grasslands, lakes and rivers over the course of the last 120,000 years. Dr. Rik Tjallingii, Professor Martin Claussen and their colleagues from the Center for Marine Environmental Research and the Alfred-Wegener-Institute in Germany studied a marine sediment core off the coast of Northwest Africa to find out how the vegetation and the hydrological cycle of the Sahara and Sahel changed over this period.
They tried to reconstruct the vegetation cover of the last 120,000 years by studying changes in the ratio of wind-transported and river-transported particles found in the core. They claim that the three “green” periods were caused by an increase in precipitation that resulted in a much larger vegetation cover, which in turn caused less wind dust, even more rainfall and stronger river
activity. According to the scientists, the “green Sahara” periods corresponded with changes in the direction of the earth’s rotational axis which determine the level of solar energy that reaches the tropical Atlantic Ocean.
The higher solar energy is believed to have increased evaporation over the ocean and
to have pushed the African monsoon further north, increasing rainfall over the Sahara.
Climate scientists do not agree how the future climate of the Sahara and the Sahel will look like. Most climate models simulate and predict an increase in rainfall as has been happening for the last 30 years. According to Professor Claussen, North Africa is the area of greatest disagreement among climate scientists. Claussen explains that forecasting how global warming will affect the Sahel is complicated by the region’s vast size and the unpredictable influence of high-altitude winds that disperse monsoon rains. In fact the increase of monsoons during the monsoon season is one of the greatest factors in the greening of the desert by planting trees the collection of ground water and growth of underbrush can only speed up the changes.
Claussen has considered the likelihood of a greening of the Sahara due to global warming and concluded that an expansion of vegetation into today’s Sahara is occurring as a consequence of CO2 emissions. His climate models suggest that the natural rate of greening could be fast,10 percent or more of the Sahara per decade with nations creating tree planting programs (especially those that bear edible fruits) this could double that speed. Fruit trees play an important nutritional role for livelihoods of rural people in the West African Sahel through provision of energy and nutrients such as vitamins, minerals, and proteins.
Research on the domestication of local fruit trees has started recently through projects concentrating on some of the most important indigenous species of dry West Africa, i.e. Adansonia digitata (the Baobob Tree)Traditionally, baobab leaves, bark, and seeds have been used to treat “almost any disease,” including malaria, tuberculosis, fever, microbial infections, diarrhea, anemia, toothache, and dysentery. The leaves and fruit pulp have been used to reduce fever and stimulate the immune system. Parkia biglobosa,Parkia plants are likely to contain constituents with broad and diverse biological activities, such as antidiabetic, antimicrobial, antihypertensive, and anti-inflammatory.
Tamarind trees (Tamarindus indica) is a leguminous tree bearing edible fruit that is indigenous to tropical Africa and naturalized in Asia. Vitellaria paradoxa commonly known as the Shea tree is one of the most important sources of vegetable oil in rural areas of the Sahel of West Africa. The bulk of the seed produced is for home consumption and local trading. Ziziphus jujuba has been used to treat various diseases such as respiratory system diseases (asthma, cough, and laryngitis), gastrointestinal problems (constipation, colitis and liver diseases), as well as cardiovascular and genitourinary system diseases. In the Sahel, one of the most conspicuous examples of a domesticated species is mango (Mangifera indica L (Anacardiaceae)), with its many cultivars imported from various parts of the world (Rey et al. 2004).
There is uncertainty regarding the future climate of the Sahel and the Sahara and it is obvious that nobody really knows if the future climate will be wetter or drier. The only certainties are the observed increases in vegetation and rainfall during the last three decades.
Conclusion: In spite of the gloomy predictions of even more frequent and severe droughts and famines caused by global warming, vegetation in the Sahel has significantly increased in the last three decades. This has been a very welcome and very beneficial development for the people living in the Sahel. The increase in rainfall, which was probably caused by rising temperatures,
and rising CO2 concentrations might even - if sustained for a few more decades - A Green Sahel and Sahara. This would be a truly tremendous prospect.
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