The UN’s Intergovernmental Panel on Climate Change (IPCC) has released a major new report, pulling together evidence from a wide range of current and ancient climate observations, that reflects the most up-to-date understanding of climate change yet. It is crucial that we have a good understanding of the findings as they give an indication of what our future could look like.
According to the report, global warming is evident, with each of the past four decades being successively warmer than any decade that preceded it since reliable record-keeping began in 1850. Average precipitation on land has also increased since the mid-20th century. In addition, there is high confidence that the mean sea level rose 15cm-25cm from 1901 to 2018.
The major concern is that as warming continues, more extreme climate events, such as droughts, are projected to increase in frequency and intensity. This warming is mainly driven by greenhouse gas emissions from human activities such as burning fossil fuels.
The report projects an increase in average temperatures and hot extremes across Africa. The continent will likely 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 events are projected to increase almost everywhere in Africa.
Looking into the future, global warming could lead to an increase in hot extremes, including heatwaves. It could also lead to a decrease in cold extremes.
The projected dry and hot conditions will have a devastating impact on a continent where most economies and the livelihoods of most people depend on rain-fed agriculture. In fact, changes to the climate will affect almost all aspects of our lives.
Regional impacts
If global warming reaches at least 2°C by mid-century (as predicted by the report), Southern Africa is highly likely to experience a reduction in mean precipitation (rain, drizzle, hail and snow). This will adversely affect agriculture. Specifically, the region is likely to witness an increase in aridity and droughts. We are already seeing this in Madagascar and SA.
This has serious implications for all sectors including agriculture, water and health. Drought would also likely reduce hydroelectric generation potential, adversely affecting energy-dependent sectors. We are already seeing this at the Kariba Dam on the Zambezi River.
In addition, there will be more tropical storms. In Southern Africa there’s been a southward shift in the occurrence of tropical cyclones as sea temperatures rise. The concern is that these events will be particularly destructive, as seen in Madagascar and over Mozambique.
For East Africa, the report projects an increase in mean precipitation that favours agriculture. However, increases in the frequency and intensity of heavy precipitation and flooding may cause a counter-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 the general circulation models, used in compiling IPCC reports, do not properly simulate the observed rainfall over the region.
A concerted effort is needed to strengthen response mechanisms to climate change
Most models project an increase in rainfall while observations report the opposite. This has been termed “the paradox of East Africa climate”. This observed shortening of rainfall season that is not captured by the models explains the paradox.
Higher temperatures will reduce snowfall and shrink glaciers in the region. They will result in a rise in malaria cases, especially in highland areas within the region.
North Africa is a climate change hotspot. The report, with “high confidence”, says the region can expect extreme heatwaves and worsening water shortages. This will increase the risk of forest fires, a threat to ecosystems. In Algeria, more than 100 such fires have broken out across 17 provinces so far this year, killing more than 40 people.
On a positive note, the report suggests the region will suffer fewer lung-harming dust storms due to reduced wind speeds.
Similarly, mean precipitation is projected to drop in West and Central Africa, leading to more agricultural and ecological droughts.
Along African coastlines, rising sea levels are likely to contribute to an increase in the frequency and severity of flooding in low-lying areas, like the recent cases in Lagos, Nigeria. This causes massive destruction to coastal ecosystems and will displace communities. The sea-level rise equally causes saltwater intrusion, limiting the availability of fresh water.
How will Africa cope?
Despite the projection of a decrease in mean precipitation over nearly all the regions of Africa, heavy precipitation and pluvial flooding are likely. The increase in wet extremes has far-reaching effects on nearly all socioeconomic sectors, from agriculture, water and the environment to infrastructure.
This, compounded by growing populations, gives a worrying picture of the challenges that lie ahead; a concerted effort is needed to strengthen response mechanisms to climate change.
• Ongoma is an assistant professor in climate change adaptation at the Université Mohammed VI Polytechnique in Morocco.
• This article was first published by The Conversation
Would you like to comment on this article?
Sign up (it's quick and free) or sign in now.
Please read our Comment Policy before commenting.