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The Sahel region of Sub-Saharan Africa stands at the frontline of one of the world’s most pressing environmental crises. Across Africa’s semiarid Sahel region, temperatures have risen faster than the global average, resulting in severe threats to water access, food security, and human health. This vast semi-arid zone, stretching approximately 6,000 kilometers from the Atlantic coast of Senegal through Mali, Burkina Faso, Niger, Chad, and Sudan, serves as a critical transition zone between the Sahara Desert to the north and the more humid savannas to the south. The Sahara Desert has expanded south into the Sahel, a 6,000-kilometre belt of semi-arid savannah stretching from Senegal, Niger, Mali, Chad, to Sudan, which is home to some 400 million people. The environmental changes unfolding in this region threaten the livelihoods of hundreds of millions of people and pose fundamental challenges for sustainable development across the African continent.
Understanding the Sahel Region and Its Climate
The Sahel region of West Africa is a semi-arid zone between the Sahara Desert and the humid Gulf of Guinea coast, roughly between 10-20°N. The region’s climate is characterized by extreme variability, with an intense dry season from November to March and an irregular rainy season between May and October. This climatic pattern makes the Sahel particularly vulnerable to environmental changes, as this region is irrigated by summer monsoon rains and rain-fed agriculture is the primary sustenance for Sahel populations.
The Sahel’s climate system is intricately connected to both global and regional atmospheric circulation patterns. Sahel rainfall is dynamically linked to the global Hadley cell and to the regional monsoon circulation. It is therefore susceptible to forcings from remote oceans and regional land alike. This complex interplay of factors makes the region’s climate highly sensitive to both natural variability and human-induced climate change.
Historical Context: The Great Droughts of the 20th Century
The Sahel has experienced dramatic climate fluctuations throughout the 20th century. The climate of the Sahel, the semi-arid southern edge of the Sahara Desert, has been the focus of attention since the sudden onset of drought in the late 1960s. In the 1970s and 1980s, the semi-arid Sahel, the southern edge of the Sahara Desert, experienced spatially uniform drought, from the Atlantic Ocean to the Red Sea.
Significant droughts occurred in the 1960s, 1970s, and 1980s, leading to widespread famine and the loss of over one million lives due to crop failures. Between 1968 and 1974, grazing became nearly impossible, triggering a widespread famine that prompted the first major mobilization of international humanitarian aid. These devastating droughts fundamentally changed how the international community understood the relationship between climate variability and human vulnerability in semi-arid regions.
During the second half of the 20th century, the Sahel experienced a major shift in climate – from a relatively wetter period in the 1950s and 1960s to a dryer climate in the 1970s and 1980s leading to severe droughts, which caused humanitarian crises. Higher rainfall rates returned to the Sahel in the 1990s, which is still below the levels of the pre-drought period of the 1940s. However, rainy season characteristics have changed: rainfall is more intense and intermittent and wetting is concentrated in the late rainy season and away from the west coast.
Primary Causes of Droughts and Desertification in the Sahel
Rising Global Temperatures and Altered Weather Patterns
Observed surface temperatures have generally increased over Africa since the late 19th century to the early 21st century by about 1 °C, but locally as much as 3 °C for minimum temperature in the Sahel at the end of the dry season. Average temperatures increased by between 0.6°C and 0.8°C from 1970 to 2010, and long-term projections indicate further temperature increases of between 3°C and 6°C.
These rising temperatures have profound effects on the region’s water balance. A higher temperature would lead to higher rates of water evaporation and a greater demand for water. The warming also affects atmospheric circulation patterns that govern rainfall distribution. Warming of the oceans enhances the stability of the tropical atmosphere and weakens deep ascent in the Hadley circulation. Warming of the Sahara and of the nearby oceans changes the structure and position of the regional shallow circulation and allows more of the intense convective systems that determine seasonal rain accumulation.
Ocean-Atmosphere Interactions
Scientific research has revealed that ocean temperatures play a crucial role in determining Sahel rainfall patterns. Sea surface temperature anomalies were the dominant forcing of the drought of the 1970s and 1980s. Research indicates that these droughts correlate more closely with changes in ocean temperatures affecting regional precipitation patterns.
On multi-year timescales, a warmer north Atlantic and Mediterranean enhance Sahel rainfall through increased meridional convergence of low-level, externally sourced moisture. The complex interactions between different ocean basins create variability in rainfall patterns that can persist for years or even decades.
Human-Induced Land Degradation
While climate factors are significant, human activities have substantially exacerbated land degradation in the Sahel. The climate crisis, coupled with population growth, extensive farming, and overgrazing, has eroded the soil and degraded ecosystems in Africa. Desertification—a process where marginal lands lose vegetation—has been exacerbated by overgrazing and deforestation, contributing to climate challenges in the area.
Overgrazing occurs in the region, especially during drought. Overgrazing leads to the decimation of vegetation, and this leads to decrease of the land surface albedo—that is, the surface absorbs more incident radiation from the Sun, increasing the temperature at the land surface. This creates a feedback loop where land degradation contributes to further warming and drying.
The high rate of population growth in the Sahel puts pressure on natural resources and makes the environment vulnerable to land degradation, in particular vegetation cover. Throughout the 2010s and 2020s, human populations and livestock grazing in the region steadily increased the progress of desertification.
Deforestation and Agricultural Practices
Countries in North Africa, such as Morocco, are losing between 0.5% and 0.8% of their forests annually, according to the Global Forest Watch 2024 Report. This deforestation diminishes the soil’s ability to retain moisture and nutrients. Unsustainable agricultural practices also play a critical role in worsening the crisis. Techniques such as deep ploughing and excessive water use contribute significantly to the issue, with estimates indicating that such practices are responsible for around 20% of desertification in the region.
Environmental Impacts of Desertification
Soil Degradation and Erosion
Lack of vegetation would result in severe soil erosion from flash floods and wind erosion, as observed around Lake Chad. The loss of vegetation cover removes the protective layer that shields soil from the erosive forces of wind and water. The change in land use and land cover affects the climate of the region, including the production of dust, and contributes to a positive feedback loop leading to greater desertification and climate change.
According to the United Nations Convention to Combat Desertification (UNCCD), Africa finds itself at the front lines of this silent crisis and undergoes a rate of desertification nearly twice the global average. Every year, with the almost 100 million hectares of fertile land that disappear worldwide, we lose a promise of harvests, stability and life.
Agricultural Productivity Decline
Rainfed farming is unsuitable for 28.83% of the region in dry years. This dramatic reduction in cultivable land has severe implications for food production. In 2023, Morocco saw a 40% drop in cereal production compared to its typical annual averages, according to reports by the Food and Agriculture Organization.
Without immediate measures, the continent’s agricultural production could fall by 17 to 22% by 2050, exacerbating food insecurity, rural poverty, and conflicts over access to land and water. Agriculture is one of the most vulnerable sectors, as most African farmers rely on rainfed crops. Reduced and unpredictable rainfall, combined with higher temperatures, drives soil moisture loss, desertification (especially in the Sahara) and shifts suitable growing areas. These changes lower yields of staple crops, undermining food security and worsening hunger.
Biodiversity Loss and Ecosystem Degradation
Desertification is widespread in the Sahel, and it appears to be moving southward. This southward expansion threatens diverse ecosystems and the wildlife they support. Multidecadel- to centennial-scale droughts have occurred in the Sahel, and the region’s climate has changed over several millennia as it has experienced desertification.
However, there have been some positive developments. As soon as a sufficiently long time series of satellite observations became available, it highlighted an upward trend in vegetation cover since the driest early 1980s, known as the regreening of the Sahel, which defied all notions of irreversible desertification. Recent earth observations show a positive trend in rainfall and vegetation index over the last decades, known as the re-greening of the Sahel.
Socioeconomic Impacts on Communities
Food Insecurity and Malnutrition
In countries like Morocco, Algeria, and Tunisia, prolonged drought periods have caused severe declines in agricultural productivity and the mass death of livestock, leaving thousands without sufficient food supplies. Large segments of the African population depend on climate-sensitive livelihoods such as agriculture (55 – 62% of the workforce in sub-Saharan Africa) and already live in poverty, heightening their exposure to shocks. Health outcomes worsen as heat stress, vector-borne diseases (such as malaria and dengue), and malnutrition become more prevalent.
Water Scarcity
In general, water resources in the Sahel are distributed unequally both over space and time. Some countries, such as Nigeria, have abundant water resources, while others, such as Burkina Faso, have to deal with water scarcity. Few surface waters exist in the Sahel; the Niger River and Lake Chad are the two dominant surface-water bodies in the region.
Forced Migration and Displacement
Mounting climate pressures act as threat multipliers for both violent conflict and internal displacement across countries spanning Senegal to Sudan. With 8 million internally displaced persons in the region now, urban areas face overburdened infrastructure while attempting to host influxes of traumatized, impoverished migrants facing further risks.
These dynamics are a source of impoverishment for households, mainly farmers, leading to population displacements, the exodus of many young people and fights over the exploitation of land and natural resources. The displacement of populations creates additional pressures on host communities and can exacerbate existing tensions over scarce resources.
Conflict and Social Instability
Key climate factors such as desertification interact with ethnic and economic tensions, exacerbating violence between pastoral and farming groups competing over degraded productive land and water resources. As resources become scarcer, competition intensifies between different groups, particularly between pastoralists who need grazing land for their livestock and farmers who need land for cultivation.
These climatic phenomena are combined with other challenges: accelerating demographic growth, low economic productivity, lack of diversification of production, political conflicts and crises, inter-community tensions and the rise of violent extremism. The convergence of environmental stress and social vulnerabilities creates conditions conducive to instability and conflict.
Economic Consequences
According to a WMO report, published in 2024, Africa “loses on average 2% to 5% of its GDP each year” due to climate hazards. Increasing aridification would have led to a 12% decline in African GDP between 1990 and 2015. The economic repercussions could be significant for the countries of the Sahel: loss of GDP, lower agricultural yields, reduced labour productivity, damaged infrastructure weakened by more frequent flooding.
On average African countries face climate-related losses amounting to 2-5% of GDP annually, while adaptation costs in sub-Sahran Africa are projected at USD 30-50 billion per year over the next decade.
Future Climate Projections for the Sahel
Temperature and Precipitation Trends
The Sahel is highly exposed to climate change, yet impacts vary across different regions. The Sahel will gradually become hotter, with some areas experiencing increased, but erratic rainfall. Extreme weather events, including droughts and floods, are expected to intensify in this context.
Current climate models (as summarised in the IPCC Sixth Assessment Report) predict increases in frequency and intensity of drought and heavy rainfall events. They also predict decreases in mean precipitation almost everywhere in Africa, with medium to high confidence. However, the picture is complex and varies across the region.
Regional Variations in Climate Change
The recovery that ensued is projected to continue in the center and east, leaving the west out. Precipitation decreases over the western Sahel (i.e., Senegal and western Mali) and increases over the central Sahel (i.e., eastern Mali, Burkina Faso and Niger).
A zonal contrast in precipitation will develop at the end of the century, with an increase in precipitation over the central Sahel and a decrease in precipitation over the western Sahel. Under a high emission scenario, Sahel rainfall variability increases, featuring a higher frequency of both extreme wet and dry seasons. The increase of rainfall interannual variability is stronger in the central-eastern Sahel than in the western Sahel.
Extreme Weather Events
Extreme weather events, such as droughts and heavy rains, could become more frequent and worsen in the Sahel region. According to scientists, increasing carbon emissions from fossil fuels are leading to longer and more intense rainy seasons, which can cause flooding. Frequency of extreme Sahelian storms tripled since 1982 in satellite observations.
Comprehensive Strategies to Mitigate and Adapt
Sustainable Land Management Practices
Implementing sustainable land management is crucial for reversing land degradation and building resilience. Sahel farming systems should opt for highly flexible agricultural practices based on the above-identified cultivable areas. This includes practices such as contour farming, terracing, and the use of organic matter to improve soil structure and water retention.
Agroforestry systems, which integrate trees with crops and livestock, offer multiple benefits including improved soil fertility, enhanced water retention, and diversified income sources for farmers. Local communities are also experimenting with sustainable practices like agroforestry and water harvesting, drawing on their Indigenous knowledge to support the natural restoration of the land. This helps communities adapt to the climate crisis by boosting agricultural production even in drought years, leading to economic empowerment and strengthening community cohesion.
Reforestation and Afforestation Initiatives
The Great Green Wall initiative represents one of the most ambitious reforestation projects in the world. The Great Green Wall, an African-led initiative aiming to restore 100 million hectares of currently degraded land in the Sahel. This project aims to create a mosaic of green and productive landscapes across the width of Africa, from Senegal to Djibouti.
In Niger, for example, local communities’ efforts led to the restoration of over 6 million hectares, about 50% of the country’s cultivated area. These successes demonstrate that with proper support and community engagement, large-scale restoration is possible.
However, challenges remain. The Great Green Wall has found obstacles, as many trees have died due to a lack of water or poor adaptation to local conditions. This highlights the importance of selecting appropriate species and ensuring adequate water management systems are in place.
Developing Drought-Resistant Crops
Agricultural research and development must focus on breeding and promoting crop varieties that can withstand the increasingly harsh conditions of the Sahel. This includes developing varieties with shorter growing seasons to match the unpredictable rainfall patterns, as well as crops with deeper root systems that can access water during dry periods.
Traditional crop varieties that have evolved in the region over centuries often possess valuable traits for drought resistance and should be preserved and integrated into modern breeding programs. Combining traditional knowledge with modern agricultural science can yield crops better suited to the challenging Sahel environment.
Water Conservation and Management Techniques
Efficient water management is critical in the water-scarce Sahel. Techniques such as rainwater harvesting, construction of small-scale water retention structures, and improved irrigation systems can significantly enhance water availability for agriculture and domestic use.
Traditional water management practices, such as the construction of half-moons (small semicircular earthen structures that capture rainwater) and stone lines (barriers that slow water runoff and promote infiltration), have proven effective in many Sahel communities. Scaling up these practices while incorporating modern water management technologies can improve water security across the region.
Climate-Smart Agriculture
Climate-smart agriculture integrates multiple approaches to increase productivity, enhance resilience, and reduce greenhouse gas emissions. This includes practices such as conservation agriculture (minimal soil disturbance, permanent soil cover, and crop rotation), integrated pest management, and precision agriculture techniques that optimize input use.
Diversification of farming systems, including the integration of livestock with crop production and the cultivation of multiple crop species, can reduce vulnerability to climate shocks and provide more stable income sources for farming families.
Early Warning Systems and Climate Information Services
Developing and strengthening early warning systems for droughts, floods, and other climate-related hazards is essential for reducing vulnerability. These systems should integrate climate forecasts, satellite observations, and ground-based monitoring to provide timely and actionable information to farmers, pastoralists, and decision-makers.
Climate information services that provide seasonal forecasts and long-term climate projections can help communities and governments make informed decisions about crop selection, planting times, and resource allocation. Ensuring that this information reaches rural communities in accessible formats is crucial for its effective use.
Strengthening Community Resilience
Building resilient communities requires addressing not only environmental challenges but also social and economic vulnerabilities. This includes improving access to education, healthcare, and financial services, as well as strengthening social safety nets that can help communities cope with climate shocks.
Supporting women’s empowerment is particularly important, as women play crucial roles in agriculture, water management, and household food security in the Sahel. Ensuring women have equal access to land, credit, training, and decision-making processes can significantly enhance community resilience.
Conflict Prevention and Resolution Mechanisms
Addressing the links between climate change, resource scarcity, and conflict requires strengthening mechanisms for peaceful resource management and dispute resolution. This includes supporting traditional conflict resolution systems, establishing clear and equitable rules for resource access, and promoting dialogue between different user groups.
Land tenure security is also crucial, as secure rights to land and resources provide incentives for sustainable management and reduce conflicts. Governments should work to clarify and formalize land rights while respecting customary tenure systems.
International Support and Financing
Climate Finance and Investment
Nearly 30% of the Sahel Alliance’s projects are aligned with the Rio climate markers, covering climate change mitigation, adaptation, biodiversity and combating desertification. Funding mainly involves adaptation initiatives, primarily in the agricultural sector, as well as mitigation projects in the energy sector.
The agricultural sector accounts for 23% of the Sahel Alliance’s total portfolio, i.e. more than €6 billion out of a total of €26.4 billion. These funds are largely allocated to regional programmes, mainly in Niger, Burkina Faso and Mali.
However, funding gaps remain significant. According to the United Nations, the Great Green Wall initiative still requires at least 33 billion US dollars in funding to achieve its 2030 target, as such, global support is fundamental. The scale of the crisis is far too big to finance back strategies by the continent alone, considering also that many more projects are stalling due to lack of funding, coordination, or political instability.
Global Implications and Responsibilities
Climate change in Africa is a serious threat as Africa is one of the most vulnerable regions to the effects of climate change, despite contributing the least to causing it. This fundamental injustice underscores the moral imperative for international support.
The spread of the Sahara Desert is not just a regional problem, is a global one. As land becomes uninhabitable, migration to Europe increases. If Africa can successfully restore its degraded lands, it could remove up to 250 million tons of carbon from the atmosphere annually. This demonstrates that supporting Sahel restoration efforts benefits the entire planet.
The Role of Technology and Innovation
Remote Sensing and Monitoring
In 2024 a map of land degradation in Africa (SDG indicator 15.3.1) was produced, widely analyzed and commented on in the documentary book: African Land: The degradation and the Absolute Requirement of Sustainable Management. In addition, several platforms and geo-servers integrating data and satellite imagery have been developed to support decision-making of member countries in their fight against land degradation.
Satellite technology and remote sensing provide invaluable tools for monitoring vegetation cover, soil moisture, land use changes, and the effectiveness of restoration efforts. These technologies enable large-scale monitoring that would be impossible through ground-based observations alone.
Mobile Technology and Information Dissemination
The widespread adoption of mobile phones across the Sahel offers opportunities for delivering climate information, agricultural advice, and early warnings directly to farmers and pastoralists. Mobile-based platforms can also facilitate access to financial services, market information, and extension services.
Renewable Energy Solutions
Expanding access to renewable energy, particularly solar power, can reduce dependence on biomass fuels (which contributes to deforestation) and support productive activities such as irrigation, food processing, and small-scale manufacturing. Solar-powered irrigation systems, for example, can enable year-round cultivation in areas with adequate groundwater resources.
Policy and Governance Frameworks
National and Regional Coordination
National multisectoral platforms bring together stakeholders from the three Rio Conventions (climate, land, biodiversity): technical ministries, specialized agencies, research centers, local authorities, and civil society Organizations. Such coordination mechanisms are essential for ensuring coherent and effective responses to the interconnected challenges of climate change, land degradation, and biodiversity loss.
Integrating Climate Considerations into Development Planning
Climate change adaptation and mitigation must be mainstreamed into all aspects of development planning, from infrastructure development to education policy. This requires building capacity within government institutions to understand and address climate risks, as well as ensuring that climate considerations are integrated into budgeting and investment decisions.
International Cooperation and Agreements
The Sahel’s challenges require coordinated international action. The United Nations Convention to Combat Desertification (UNCCD), along with the other Rio Conventions on climate change and biodiversity, provides frameworks for international cooperation. However, international efforts to halt desertification remain fragmented, underfunded, and even overshadowed.
Success Stories and Lessons Learned
Community-Led Restoration
Many of the most successful restoration efforts in the Sahel have been community-led initiatives that combine traditional knowledge with modern techniques. These projects demonstrate that when communities have secure rights to land and resources, and receive appropriate technical and financial support, they can achieve remarkable results in restoring degraded landscapes.
Farmer-Managed Natural Regeneration
Farmer-managed natural regeneration (FMNR), a technique that involves protecting and managing the regrowth of trees from existing root systems, has proven highly effective and cost-efficient in several Sahel countries. This approach requires minimal external inputs and can be implemented by farmers themselves, making it highly scalable.
Integrated Landscape Approaches
Successful interventions increasingly recognize that addressing desertification requires integrated approaches that consider entire landscapes rather than isolated plots. This means coordinating actions across different land uses (agriculture, grazing, forestry) and involving all stakeholders in planning and implementation.
Challenges and Barriers to Implementation
Political Instability and Insecurity
Many parts of the Sahel face significant security challenges, including armed conflict and violent extremism. These conditions make it difficult to implement long-term development and restoration projects, disrupt livelihoods, and force people to abandon their lands.
Institutional and Capacity Constraints
Many Sahel countries face constraints in terms of institutional capacity, technical expertise, and financial resources needed to implement effective climate adaptation and land restoration programs. Strengthening these capacities requires sustained investment in education, training, and institutional development.
Coordination Challenges
The involvement of multiple actors—governments, international organizations, NGOs, private sector, and local communities—while beneficial, can also create coordination challenges. Ensuring effective communication, avoiding duplication of efforts, and aligning different initiatives toward common goals requires strong coordination mechanisms.
The Path Forward: A Call to Action
The challenges facing the Sahel are immense, but they are not insurmountable. Africa also remains a continent of hope, driven by traditional knowledge, a strong local dynamic for land restoration, and the growing commitment of its youth to building a sustainable and resilient future. Africa reminds the world that it is not only a continent of crises, it is also a continent of proposals, rich in initiatives, resilience, and solutions. Restoring its land means reconciling social justice, economic prosperity, and ecological sustainability.
Addressing the drought and desertification crisis in the Sahel requires action at multiple levels. Local communities must be empowered and supported to implement sustainable land management practices. National governments must prioritize climate adaptation and land restoration in their development plans and policies. Regional organizations must facilitate cooperation and coordination across borders. And the international community must provide the financial and technical support needed to implement solutions at scale.
If current practices continue unchecked, more than half of the African continent’s arable land is expected to become unusable by 2050. This stark warning underscores the urgency of action. However, with concerted effort, adequate resources, and sustained commitment, it is possible to reverse land degradation, build resilience to climate change, and secure sustainable livelihoods for the hundreds of millions of people who call the Sahel home.
The future of the Sahel—and indeed, the future of millions of people whose lives depend on this fragile ecosystem—hangs in the balance. The time for action is now. By combining traditional knowledge with modern science, mobilizing adequate financial resources, strengthening governance and institutions, and ensuring that local communities are at the center of decision-making, we can turn the tide against desertification and build a more sustainable and prosperous future for the Sahel region.
Additional Resources and Further Reading
For those interested in learning more about climate change impacts in the Sahel and ongoing efforts to address them, several organizations provide valuable information and resources:
- The United Nations Convention to Combat Desertification (UNCCD) provides comprehensive information on global efforts to combat desertification and land degradation, with specific focus on vulnerable regions including the Sahel.
- The Sahara and Sahel Observatory offers scientific data, monitoring tools, and analysis related to environmental changes in the region.
- The Great Green Wall Initiative website provides updates on this ambitious pan-African restoration project and opportunities for engagement and support.
- The Intergovernmental Panel on Climate Change (IPCC) publishes detailed assessment reports on climate change impacts in Africa, including specific chapters on the Sahel region.
- Organizations such as the World Resources Institute and International Union for Conservation of Nature (IUCN) provide research, tools, and case studies on land restoration and climate adaptation in drylands.
Understanding the complex challenges facing the Sahel is the first step toward meaningful action. By staying informed, supporting effective interventions, and advocating for adequate resources and political attention to this critical region, we can all contribute to building a more sustainable future for the Sahel and its people.