Extreme Weather in Sub-Saharan Africa and its associated risks

Waka Africa Org Climate Change Journal by John Ouma, Director Department of Climate Change and Research, A Waka Editorial Publication

It is hard to point out that the extreme weather conditions in Sub-Saharan Africa could be due to the temperature rise, given that the temperature rises in the region started long before the industrial age. However, although Africa contributes 2-3% of the global GHG emissions, climate change has hit the region hard (Climate Change Is an Increasing Threat to Africa | UNFCCC, 2020). There have been reports of three consecutive rain seasons that have failed to occur in East Africa, a condition that has exacerbated the food crisis in the region. The study by UNFCCC (2020) links the trend to the rising regional temperature at +0.3 °C/decade in 1991-2021, faster than the 1961-1990's +0.2°C/decade. The temperature of hot days will increase by 1.5-2°C in the Western part of Africa, with the Southern part experiencing a higher rate of temperature rise than 2°C.

On the other hand, the African coastline has been experiencing rising sea levels at a higher rate than the global mean rate, more so along the Red Sea and southwest Indian Ocean, where the rate is 4mm/year. These differences in the sea level trends across the African coastline, with some oceanic regions reporting an increase of up to 5 mm/year, whereas the South Western Indian Ocean from the east of Madagascar towards and beyond Mauritius has recorded a sea level increase of more than 5 mm/year (Kappelle, 2020). With projections that the rising sea level will keep increasing, there will be more severe coastal flooding in low-lying cities with high volumes of saline water due to seawater (saltwater) intrusion on the land as is the case of China (China’s Transition to a Low-Carbon Economy and Climate Resilience Needs Shifts in Resources and Technologies, n.d.). For example, 56% of the coastlines in Benin, Côte d'Ivoire, Senegal, and Togo are eroding, which is expected to worsen (Climate Change Is an Increasing Threat to Africa | UNFCCC, 2020). About 108-116 million people in Africa will be exposed to sea level rise by 2030. 

Flooding

Frequent uneven flooding across the continent has been recorded in countries such as South Sudan, Nigeria, DRC, the Republic of Congo, and Burundi. The flooding has been due to a high amount of rainfall in 2020 and 2021 that has led to elevated levels of rivers and lakes. In Kenya, for example, Lake Naivasha has been reported to expand, affecting several people, whereas Lakes Baringo and Bogoria threaten to merge, possibly creating anticipation of an ecological disaster. The Budalangi residents in Kenya have almost been forced out of their homes every rainy season due to the flooding from River Nzioa. The high precipitation could be due to the retreating of glaciers on Mt. Kenya, Mt. Kilimanjaro, and the Ruwenzori Mountains at a higher rate the global mean to less than 20% of what they were in the late 19Th century (State of the Climate in Africa, 2021). Similarly, the total surface area of Lake Chad has shrunk from 25,000 km2 in the 1960s to about 1350 km2 as of 2000, representing a 90% decrease, and has remained stable since then. The shrinking has reduced the volume of freshwater for Chad, Cameroon, Nigeria, and Niger.

Extreme Weather and the Economic Cost

The International Monetary Fund (IMF) estimates that the severe consequences of climate change will be borne by the regions with relatively hot climates, where many low-income countries are located. In the past 50 years, drought-related hazards have led to over 500,000 fatalities, with an estimated economic loss of over US$ 70 billion(Climate Change is an Increasing Threat to Africa | UNFCCC, 2020). The effects come against the backdrop of over 1,000 flood-related disasters that have caused more than 20,000 deaths in the continent over the same period. The harsh climate will collectively cost African countries US$ 50 billion annually by 2050. For example, the African Climate Policy Centre projects that the Gross Domestic Product (GDP) of five African sub-regions would decrease significantly due to the rise in the global temperature. For an increase of 1-4°C in the earth's temperature about the pre-industrial levels, the continent's overall GPD is forecasted to drop by 2.25-12.12%, with West, Central, and East Africa bearing the effects more than the North and South of Africa (Climate Change is an Increasing Threat to Africa | UNFCCC, 2020).

Extreme Weather and Food Security

High temperatures caused a 34% dip in agricultural production since 1961, more than any other region globally. The United Nations Food and Agriculture Organization (FAO) has estimated that the number of malnourished people in Sub-Saharan Africa has increased by 45.6% since 2012 (Climate Change is an Increasing Threat to Africa | UNFCCC, 2020). The observation is due to the Sahel region's dependence on rain-fed agriculture, which is often hit hard by draughts and famines (Global Warming, 2018). Given that the situation is expected to increase, food insecurity and malnutrition will increase. As projected, a 1.5% rise in temperature will come with a 9% reduction in the production of maize in West Africa and a 20-60% decline in wheat yield in Southern and Northern Africa due to drought, heat stress, diseases, floods, and pest damage. A 13% decrease in the mean yield is expected in West and Central Africa, 11% in the North, and 8% in East and Southern Africa by 2025. Millet and sorghum are the most promising crops to withstand heat-stress conditions, with 5% and 8% yield losses over the same period (Climate Change is an Increasing Threat to Africa | UNFCCC, 2020).

Displacement

Climate-related disasters have continued to be a significant driver of many African displacements. Crises like chronic floods, droughts, sea level rise, and extreme weather directly impact displacement patterns. For example, in 2021 alone, about 2.5 million people were displaced in Sub-Saharan Africa due to climate-related disasters.

Health Impacts

High temperatures and fluctuations in rainfall patterns increase the habitat suitability for biting insects and the transmission of vector-borne diseases like dengue fever, malaria, and yellow fever. Moreover, there is an emergence of novel infections. In 2017, about 93% of global malaria deaths occurred in Africa. Malaria epidemics commonly occur after periods of heavy rainfall (Climate Change Is an Increasing Threat to Africa | UNFCCC, n.d.). In the case of high altitudes in East Africa, the increasing temperatures favor the survival of the malaria-transmitting mosquitoes.


References

4-sea-level-rise-flooding-chennai-india-who-shanth-kumar-(1).tmb-1920v.jpg (JPEG Image, 1920 × 1357 pixels)—Scaled (35%). (n.d.). Retrieved 27 May 2023, from https://www.who.int/images/default-source/health-and-climate-change/4-sea-level-rise-flooding-chennai-india-who-shanth-kumar-(1).tmb-1920v.jpg?Culture=en&sfvrsn=99d2f39e_1

Bringing dry land in the Sahel back to life | UN News. (2022, 23 January). https://news.un.org/en/story/2022/01/1110322

China’s Transition to a Low-Carbon Economy and Climate Resilience Needs Shifts in Resources and Technologies. (n.d.). World Bank. Retrieved 28 May 2023, from https://www.worldbank.org/en/news/press-release/2022/10/12/china-s-transition-to-a-low-carbon-economy-and-climate-resilience-needs-shifts-in-resources-and-technologies

Climate Change Is an Increasing Threat to Africa | UNFCCC. (n.d.). Retrieved 26 May 2023, from https://unfccc.int/news/climate-change-is-an-increasing-threat-to-africa

Climate Effects on Health | CDC. (2022, 3 May). https://www.cdc.gov/climateandhealth/effects/default.htm

Global warming: Severe consequences for Africa. (2018, 7 December). Africa Renewal. https://www.un.org/africarenewal/magazine/december-2018-march-2019/global-warming-severe-consequences-africa

Kappelle, M. (2020). State of the Climate in Africa 2019. https://doi.org/10.13140/RG.2.2.27938.25280

Photos: Heavy rains in Budalangi, Kenya; floods hamper social distancing. (2020, 6 May). Hindustan Times. https://www.hindustantimes.com/photos/world-news/photos-heavy-rains-in-budalangi-kenya-floods-hamper-social-distancing/photo-uDC8MdDvCBUlx2pYAZXJBM.html

State of the Climate in Africa. (2021, 19 August). https://public.wmo.int/en/our-mandate/climate/wmo-statement-state-of-global-climate/Africa