Africa’s forests could actually be a game-changer in terms of tackling climate change. Approximately 2.6 billion tons of carbon dioxide, one third of the CO2 released from burning fossil fuels, is absorbed by forests each year. *****Agricultural yields in Africa are low by comparative regional standards, but that production can be improved considerably by increasing the amount of land under irrigation, using more fertilisers and genetically modified seeds, and improving farming practices.However, climate change poses a major threat and will constrain such improvements, particularly in North and West Africa, as the impact of higher temperatures and shifting rainfall takes its toll. In 2006, three major flood events (normally occurring every 10-20 years) occurred within the space of two months in East Africa, displacing almost 200 000 people in Ethiopia, Somalia and Kenya and destroying thousands of hectares of cropland. Maize and wheat production have already been affected in many countries, including fisheries in the Great Lakes region and fruit trees in the Sahel. Droughts and floods are likely to become more frequent and more difficult to predict and could exacerbate food security issues and migratory push factors. In 2017 in Sierra Leone, weeks of heavy rain led to catastrophic mudslides that killed more than 600 people outside Freetown. In 2018, extreme flooding in Niger killed more than 80 people, displaced 50 000 more, and wiped out 400 hectares of farmland and 26 000 head of livestock. Meanwhile, these countries have some of the fastest-growing populations in the world. Africa has already experienced some of the most severe effects of climate change to date. The Intergovernmental Panel on Climate Change (IPCC) has identified the Sahel and West Africa as climate change "hot spots" that are projected to experience unprecedented effects of climate change, owing to their existing hot and dry climate, high rates of poverty and profound dependence on rain-fed agriculture, before anywhere else in the world. In responding to this environmental challenge, we can either adapt our way of life or resort to mitigating actions. Such efforts focus on reducing emissions and stabilising the levels of greenhouse gases in the atmosphere. In this way, mitigation is a long-term climate change response as its benefits will only emerge during the second half of the century. The Paris Agreement represents a global effort to mitigate the future impacts of climate change by trying to reduce greenhouse gas emissions now. And under the Kigali Amendment to the Montreal Protocol (the 1987 agreement to protect the stratospheric ozone layer), which came into force in January 2019, all countries will gradually phase down the production and consumption of hydrofluorocarbons and replace these with more environmentally friendly alternatives. A second possible reaction is to adapt to life in a changing climate, that is, to the change that is already locked into the climate system. For example, in June 2018 Tanzania completed 2.4 kilometres of seawalls at a cost of US$8.34 million in an effort to protect Dar es Salaam and surrounding areas from rising sea levels. According to USAID, the country is estimated to suffer about US$200 million per year in lost land and infrastructure damage due to sea level rise. On the other side of the continent, Lagos is one of the largest and fastest-growing cities in the world, but much of the city is less than one metre above sea level. Lagos is, and has always been, a city oriented towards the sea. In fact, it is expanding into the Atlantic through expensive developments on newly reclaimed land on the one hand and overpopulation in slum settlements on the other. With many of its slum communities literally built in the sea, vulnerable communities in Lagos are already highly exposed to rising sea levels and more severe storm activity caused by climate change. Seventy per cent of the population of Lagos live in slums, with a population density ten times that of New York City, so a powerful storm would affect millions. Furthermore, average sea level rise is projected at 30 centimetres by 2050 and between 30 centimetres and 1.8 metres by 2100 (rising an additional 30 centimetres or more after each decade). Against this backdrop, the "Great Wall of Lagos" promises to offer protection from climate change, but only for those Nigerians who can afford to live in Eko Atlantic – a massive Dubai-style city under construction. The 8.5-kilometre seawall will protect the shoreline of Victoria Island and early phases of Lekki (a city on a peninsula to the east of Lagos) from coastal erosion. What will happen to the people of Makoko and other slum areas is, of course, an entirely different matter. And then there is the Great Green Wall. For more than a decade, affected countries in the Sahel and elsewhere have advanced and promoted the Great Green Wall of the Sahara and the Sahel Initiative (Grande Muraille Verte pour le Sahara et le Sahel), which aims to halt the southward spread of the Sahara and to constrain the impact of climate change. The original concept, which dates from colonial times, is for a belt of trees 50 kilometres wide (now reduced to 15 kilometres) to be planted to help contain the desert. The project has subsequently evolved into an integrated rural development effort to respond to the detrimental social, economic and environ-mental impacts of land degradation and desertification straddling 8 000 kilometres from Senegal in the west to Djibouti in the east.44 In 2017, it was adopted as a flagship project by the UN Conference on Sustainable Development and now involves more than 20 countries. But, apart from a minimum effort in Burkina Faso and Senegal, little progress has been made. In July 2019, Ethiopia claimed to have planted more than 353 million trees in just 12 hours as part of a wider reforestation campaign, "Green Legacy", as an example of what could be possible. This is the kind of effort that will be required to realise the Great Green Wall, possibly including moving away from the idea of a narrow band of trees along the southern edge of the Sahara, indeed across much of sub-Saharan Africa. Africa’s forests could actually be a game-changer in terms of tackling climate change. Approximately 2.6 billion tons of carbon dioxide, one third of the CO2 released from burning fossil fuels, is absorbed by forests each year. "Halting the loss and degradation of forest ecosystems and promoting their restoration,’ according to the International Union for Conservation of Nature (IUCN), have the potential to contribute over one third of the total climate change required by 2030 to meet the objectives of the Paris Agreement."According to the Global Forest Watch, treecover loss peaked in 2016 but the overall trend is still upward. The DRC is now the country with the second-largest losses by area, and Madagascar lost two per cent of its entire primary forest in 2018. Ghana and Côte d’Ivoire showed the highest rise in percentage losses of primary forest. Most of this increase, particularly in Ghana, is likely due to smallscale gold mining. There has also been an expansion of cocoa farming, which has led to forest loss. Africa does have some ability to mitigate climate change - massive tree planting is just one example - but needs to direct significant effort at adaptation. The African Union acknowledges as much in Agenda 2063, which states: "Africa shall address the global challenge of climate change by prioritizing adaptation in all our actions ... for the survival of the most vulnerable populations ... and for sustainable development and shared prosperity." - This is an edited extract of Africa First! from Jakkie Cilliers which is published by Jonathan Ball Publishers.