Spatiotemporal Analysis of African Drought Trends (1960–2018): Insights for Climate Adaptation and Water Resource Management

A recent study by Ogunrinde et al. (2025) titled “Spatiotemporal analysis of drought patterns and trends across Africa: a multi-scale SPEI approach (1960–2018)” published in the International Journal of Digital Earth reveals significant spatial variations in drought trends, with increasing dryness particularly evident in the Mediterranean and Sahara regions.

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There is increasing drought intensity, duration, and regional variability across Africa, emphasizing worsening dryness, particularly post-1990 in Mediterranean and Sahara regions.– Ogunrinde et al. 2025

The article examines drought trends across Africa from 1960 to 2018 using the Standardized Precipitation-Evapotranspiration Index (SPEI). Leveraging methodologies like the Modified Mann-Kendall test, Sen’s Slope estimator, and copula functions, the study analyzes drought characteristics across eight African subregions using the CRU TS4.05 dataset. The findings reveal significant spatial variations in drought trends, with increasing dryness particularly evident in the Mediterranean and Sahara regions. A marked shift towards drier conditions began after 1990, with mean drought duration increasing from 1.5 months (SPEI-3) to over 6 months (SPEI-24). Additionally, drought intensity has risen by 0.2 units annually, while frequency has declined by 20%. The Sahara region exhibits the steepest increase in drought trends across all timescales. Return period analyses indicate that most subregions experience short-term droughts with lower severity, though extreme events are less frequent. The study highlights the complex and region-specific nature of drought patterns across Africa, stressing the need for adaptive climate strategies tailored to each subregion. Furthermore, it emphasizes the importance of integrated drought monitoring and management systems to mitigate the adverse impacts of climate change on water resources, agriculture, and socio-economic stability across the continent.

How the Study was Conducted

The study covered the entire African continent, which is divided into eight distinct regions based on climatic and ecological characteristics: Mediterranean (MED), Western Africa (WAF), North Eastern Africa (NEAF), Sahara Africa (SAH), West Southern Africa (WSAF), East Southern Africa (ESAF), Central Africa (CAF), and South Eastern Africa (SEAF). The authors employed monthly precipitation and potential evaporation data from the Climatic Research Unit Version 4.05 (CRU TS4.05) dataset, covering the period from 1960 to 2018. This dataset provides long-term climate data essential for characterizing drought events. The Standardized Precipitation-Evapotranspiration Index (SPEI) was used to analyze drought intensity, duration, and spatial extent. It operates on a climatic water balance principle, highlighting the disparity between precipitation and potential evapotranspiration (PET). The Penman-Monteith method was employed to calculate PET. The run theory was used to identify drought events and derive various drought parameters, including drought duration (DD), drought frequency (DF), drought severity (DS), drought intensity (DI), and drought peak (DP). The modified Mann-Kendall (MMK) test was also employed to detect trends in the time series data, accounting for serial correlation. It calculates the S statistic and its variance, considering the autocorrelation structure of the data. Sen’s Slope Estimator, a non-parametric method, was used to quantify the rate of change in time-series data. It calculates the median value of all possible slope calculations between data point pairs in a time series. In addition, copula functions were used for advanced joint modeling of correlated drought characteristics, such as duration and severity. The Gamma distribution and Gumbel copula were employed to establish the joint distribution of drought duration and severity.

What the Authors Found

The study found a significant increase in dryness, particularly in the Mediterranean and Sahara regions, with trends intensifying after 1990. Mean drought duration grew from 1.5 to over 6 months, while intensity rose by 0.2 units annually, and frequency dropped by 20%. The Sahara showed the highest drought trend, with most subregions experiencing short, low-severity droughts and infrequent extreme events.

Why is this important?

Water Resource Management: Understanding drought patterns helps in managing water resources more effectively. This is vital for regions that rely heavily on rain-fed agriculture and have limited water infrastructure.

Agricultural Planning: With 95% of Africa’s agriculture being rain-fed, knowing the trends and patterns of drought can help in planning agricultural activities, ensuring food security, and mitigating the impacts of drought on crop yields.

Climate Change Adaptation: The study highlights the increasing frequency and intensity of droughts, which are likely exacerbated by climate change. This information is essential for developing adaptive strategies to cope with the changing climate.

Socio-Economic Stability: Droughts have significant socio-economic impacts, including displacement of populations, loss of livelihoods, and increased poverty. Understanding drought trends can help in creating policies to support affected communities and enhance their resilience.

Ecological Balance: Droughts affect ecosystems and biodiversity. By understanding drought patterns, conservation efforts can be better directed to protect vulnerable species and habitats.

Policy Development: The findings provide a scientific basis for policymakers to develop region-specific strategies to address drought-related challenges, ensuring sustainable development and environmental protection.

What the Authors Recommended

• The study emphasizes the need for tailored climate strategies that address the unique ecological challenges of different African subregions. This includes developing localized drought monitoring and management systems.
• The authors highlight the importance of integrated systems that combine various drought indices and metrics to provide a comprehensive understanding of drought dynamics. This can help in early warning and better preparedness.
• The study calls for sustainable management practices that ensure the efficient use of water resources. This includes investing in infrastructure that can store and distribute water more effectively during drought periods.
• Given the reliance on rain-fed agriculture in Africa, the authors recommend adopting agricultural practices that are resilient to drought. This includes using drought-resistant crop varieties and improving irrigation techniques.
• The findings provide a scientific basis for policymakers to develop strategies that mitigate the impacts of drought. This includes creating policies that support affected communities and enhance their resilience to drought conditions.
• The authors suggest that future research should focus on understanding the socio-economic impacts of drought and exploring the effectiveness of different adaptation strategies. This can help in developing more effective solutions to address the challenges posed by drought.

In conclusion, the study by Ogunrinde et al. underscores the critical need for region-specific climate adaptation strategies to address the growing challenges of drought across Africa. By providing a comprehensive analysis of drought trends, intensities, and patterns, the research highlights the urgency of integrated monitoring systems, sustainable water management practices, and resilient agricultural solutions. These findings offer a valuable foundation for policymakers, researchers, and stakeholders to develop adaptive strategies that not only mitigate the impacts of drought but also promote sustainable development, enhance socio-economic stability, and protect Africa’s vulnerable ecosystems in the face of climate change.