Climate change, which is strongly perceived in the summer in the Northern Hemisphere, does not spare Africa, where natural disasters are on the rise. Ten climate-related phenomena hit the continent more and more acutely and repeatedly.
• Heat waves and forest fires in North Africa In Morocco, heat waves have followed each other since mid-June 2022 with temperatures of 45°C, which is close to the absolute record of 50°C. in July 2021 in Sidi Slimane, in the northwest. According to the weather directorate, 2020 was the hottest year ever for the kingdom, with a national average annual temperature of +1.4°C compared to the period 1981-2010 – a very concrete measure of climate warming. Forest fires are raging as in Tunisia and Algeria, where short heat waves have been repeated since 2018 in June and July, and where forest fires are feared. And for good reason: they burned 44,000 hectares in 2020 and caused 90 deaths in 2021.
• Drought in the Sahel, the Horn and southern Africa
Arid regions are hard hit by drought, which caused severe famine in Somalia in 2010 and threatens again in 2022 – with the worst water shortage since 1981, according to United Nations. In the Sahel, this phenomenon is becoming more and more intense, a CNRS study of 2018, even confirming that in “1,600 years of climate history, the current drought in the Sahel is unprecedented”.
Southern Africa is also suffering. Namibia declared a national emergency in 2013, 2016 and 2019 when the last drought, unprecedented in 90 years, killed 100,000 cattle and devastated agriculture. With a period of strict water rationing in Cape Town in 2018-2019, South Africa, for its part, has experienced a taste of the drastic measures that will be imposed in the medium term. To anticipate future water stress, seawater desalination is spreading from Morocco to southern Africa.
• Drying up of lakes As a direct consequence of the drought, the lakes are evaporating. Lake Chad, a great oasis in the Sahel, which has already disappeared and reappeared throughout its history, has lost 90% of its surface area in 60 years, displacing more than 2 million people. Concern also hangs over Africa’s largest lake, Victoria, which is threatened with extinction with 500 to 1,200 years, according to two American scientific studies. In Mali, Lake Fabiguine has been dry since 2021, near Timbuktu, while in Djibouti, Lake Assal – the saltiest in the world – has partially dried up.
• Rise in Lake Tanganyika Conversely, the fresh water in Lake Tanganyika, the longest in the world (670 km) and one of the deepest, has been steadily increasing since 2018 – by almost two meters over the last four years. They cause floods which have 15 deaths in 2019 and affected 52,000 people in Burundi in 2021 due to torrential rains attributed to climate change. Cyclically, the phenomenon occurred every 50 to 60 years, according to the Geographical Institute of Burundi. It now breeds every year.
• Recurring cyclones in Mozambique and Madagascar The same applies to tropical cyclones, which no longer hit Madagascar and Mozambique once every two or three years, but… every year, or even twice a year. After Cyclone Idaiwhich drowned the city of Beira and left 1,000 dead in three countries in March 2019, it is Kenneth, even more intense, which devastated Mozambique a month later with winds of more than 185 km/h. Followed by Tropical Storm Chalane in December 2020, Cyclone Eloise in January 2021, Storm Ana in January 2022 and Cyclone Gombe in March 2022. At issue: the 2,700 km coastline along the Mozambique Channel, which separates the country from Madagascar. In this warm sea, the water temperature sometimes exceeds 29°C between December and April, during the austral summer, a favorable period for cyclones.
• Expansion of the floods The suburbs of Dakar scrub, every rainy season, i floods recurring since 2005. Flood records also follow each other since 2010 on the Niger River in Niamey, with 57 dead and 300,000 displaced in August 2020. The same disasters, signs of a climate becoming more extreme, prevail throughout West Africa, where 760,000 people were exposed floods in 2020, as well as in Sudan and East Africa. The “positive dipole”, a difference in sea surface temperature between the eastern and western regions of the Indian Ocean, causes recurring floods in Kenya and in Mozambique. These have spread this year to South Africa (443 died in April). When the water is warmer near the coasts, evaporation increases and so does the rain.
•Coastal erosion in West Africacoastal erosion is gaining an average of 1.8 meters per year on 56% of the coastline in Benin, Côte d’Ivoire, Senegal and Togo, according to a study byWorld Bank published in 2019. In some places, the sea has gained 2 km over land in two decades – although without certainty that it is the result of human activitysuch as the construction of deep-water ports or dams on rivers that limit the supply of sand to the sea.
• Sea level riseHowever, melting ice caps threaten coastal cities everywhere. A study by the independent research group Climate Central in 2021, ink flowed in South Africa over the risk of siphoning off Cape Town and Durban, with spectacular images to back it up. Alexandria, backed by a lake, and whose land is sinking, worries Egypt: according to a study published in 2018, 6.5 million people could emigrate from this industrial basin located in the Nile Delta by 2100 due to flooding. The Mediterranean Sea rose by 1.8mm per year from 1940 to 1993, a rate that has almost doubled according to the government, to reach 3.2mm since 2012 (i.e. an increase of 3cm in ten years against 4cm in the previous 20 years).
• Extinction of animal species
Species that depend on a particular environment, such as lemurs in Madagascar or forest elephants in Africa, are at risk of disappearing with rising temperatures. As will two-thirds of animal species in the tropics if humanity does not reduce its greenhouse gas emissions, according to a major study published in 2021 by Biological conservation. Bird species are already on the brink of extinction in East Africa, while elephant populations in Africa have declined by 70% since 1980 due to poaching and habitat destruction. It may be extinct by 2040, according to the World Wildlife Fund (WWF).
• Loss of biodiversityA third of Africa’s tropical plants, or 22,000 species, are on the brink of extinction due to deforestation, population growth and climate change, according to a ground-breaking study by The progress of science, released in 2019. Another third are listed as “rare” and potentially endangered. The hardest hit countries are in West Africa, in addition to Ethiopia, the Democratic Republic of Congo and Tanzania. The International Union for Conservation of Nature (IUCN), whose data served as the basis for the Science Advances study, maintains a red list of threatened species which will be longer – with no regional focus other than Europe and the Mediterranean, unfortunately.