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The Intergovernmental Panel on Climate Change (IPCC) – a UN body tasked with providing scientific information on climate change – has released a major new report, bringing together evidence from a wide range of current and past climatic observations. This is the most recent understanding of climate change, bringing together the latest advances in climate science.
It is crucial that we have a good understanding of the results as they give an indication of what our future might look like.
Global warming is evident, according to the report, with each of the past four decades successively warmer than all the decades before it since 1850. Average precipitation on earth has also increased since the mid-20th century. In addition, there is a high degree of confidence that the mean sea level increased by 0.15 to 0.25 m between 1901 and 2018.
The main concern is that as warming continues, more extreme weather events, such as droughts, are expected to increase in both frequency and intensity. This warming is mainly due to greenhouse gas emissions from human activities such as the combustion of fossil fuels (coal, natural gas and oil) and the production of coal.
As for African countries, the report predicts an increase in average temperatures and temperature extremes across the continent. The continent is likely to experience drier conditions with the exception of the Sahara and East Africa.
Alarmingly, the rate of temperature increase across the continent exceeds the global average. In addition, as warming continues, the frequency and intensity of heavy rainfall is expected to increase almost everywhere in Africa. Maritime heat waves and sea level rise are also expected to increase along mainland coasts.
In the future, global warming could lead to an increase in temperature extremes, including heat waves. It could also lead to a decrease in extreme cold.
The predicted hot and dry conditions will have a devastating impact on a continent where the economies of most countries and the livelihoods of most people depend on rain-fed agriculture. In fact, climate change will affect almost every aspect of our lives.
Regional impacts
In a scenario where global warming reaches at least 2 ° C by the middle of the 21st century (as predicted by the report), southern Africa will most likely experience a reduction in average precipitation (falling water vapor, as rain or drizzle or greet). This will negatively affect agriculture. Specifically, the region is likely to experience increased aridity and droughts. We can already see it in Madagascar and South Africa.
This has serious implications for all sectors, including agriculture, water and health. Drought would also likely reduce the potential for hydropower generation, negatively affecting energy-dependent sectors. We are already seeing this at the Kariba dam, located between Zimbabwe and Zambia.
In addition, there will be more tropical storms in the region. In southern Africa, the frequency of tropical cyclones has shifted south. This is due to the increase in sea temperatures due to global warming. The concern is that these events will be particularly destructive as we have seen in Madagascar and Mozambique.
Read more: Rising sea temperatures are shaping tropical storms in southern Africa
For East Africa, the report predicts an increase in average rainfall which favors agriculture. However, increased frequency and intensity of heavy rainfall and flooding may have the opposite effect in some areas, such as arid and semi-arid lands.
There has been conflicting information regarding rainfall in East Africa. This follows observations that general circulation models, used in the preparation of the IPCC reports, do not simulate the precipitation observed in the region well. Most models predict an increase in precipitation while observations report the opposite. This has been called the “East African Climate Paradox”. This observed shortening of the rainy season, which is not captured by the models, explains the paradox.
In addition to precipitation, the recorded and projected temperature which is expected to increase will lead to a decrease in snow and glaciers in the region. An increase in temperatures will lead to an increase in malaria cases, especially in the mountainous areas of the region.
North Africa is a hotspot for climate change. The report confidently predicts an increase in temperatures in the region, causing extreme heat waves. The projected drying will increase the aridity that has already started to appear in the region and exacerbate the water scarcity.
Read more: A worsening water crisis in North Africa and the Middle East
In addition, the situation will increase the risk of forest fires, a threat to ecosystems. As currently seen in Algeria where, so far this year, more than 100 fires have been reported in 17 provinces, killing over 40 people.
The report also predicted that there would be a reduction in the average wind speed over North Africa. Wind speed depends on temperature and therefore changes in atmospheric pressure. This will limit the region’s wind potential, but – on a positive note – it will also reduce dust storms that have health effects, such as causing and worsening asthma and bronchitis.
Similarly, West and Central Africa are expected to experience a reduction in average rainfall and experience more agricultural and ecological droughts. All of these cast a dark cloud over agriculture and water in the region.
Read more: Lagos receives less rain, but more severe thunderstorms. What he can do to prepare
Along Africa’s coasts, relative sea level rise is likely to contribute to an increase in the frequency and severity of coastal flooding in low lying areas, such as recent cases in Lagos, Nigeria. This is causing massive destruction of delicate coastal ecosystems and will displace communities that live in coastal cities. Rising sea levels also cause saltwater intrusion, limiting the availability of fresh water.
Read more: Climate change is affecting the livelihoods of agrarian migrants in Ghana. This is how
Which way for Africa?
Despite the projected decrease in average rainfall over almost all parts of Africa, heavy rainfall and rainfall flooding are likely. The increase in wet extremes has dramatic effects on almost all socio-economic sectors, from agriculture to water, the environment and infrastructure. These are some of the key sectors of socio-economic development.
This – compounded by population growth – paints a worrying picture of the challenges ahead. This is likely to widen the existing development gap, calling for concerted efforts to strengthen mechanisms to respond to future challenges posed by climate change.
Victor Ongoma does not work, consult, own stock or receive funding from any company or organization that would benefit from this article, and has not disclosed any relevant affiliation beyond his academic appointment.
By Victor Ongoma, Senior Lecturer, Mohammed VI Polytechnic University
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