Clim-Djeffara-40y Escalating Aridity in a Vulnerable Region: A Four-Decade Climate Assessment of Djeffara, Southeastern Tunisia (1984–2024): Quantifying Change, Diagnosing Causes, and Framing Adaptive Strategies

Imen Lajher Adouani; Naceur Mahdhi

doi:10.56027/JOASD.062026

Auteurs

Imen Lajher Adouani Laboratoire d'Economie et Sociétés Rurales, Institut des Régions Arides de Médenine, Tunisie
Naceur Mahdhi Laboratoire d'Economie et Sociétés Rurales, Institut des Régions Arides de Médenine, Tunisie

DOI :

https://doi.org/10.56027/JOASD.062026

Mots-clés :

climat, aridity, climatic trends, adaptation strategies, djeffara

Résumé

This research examines the progression of major climate parameters in the Djeffara region, located in southeastern Tunisia (33.21°N ; 10.29°E), over a forty-year period from 1984 to 2024. Monthly and annual climate data were obtained from the NASA POWER database. The factors analyzed include precipitation, relative humidity, average and extreme temperatures, wind speed, and potential evapotranspiration (ETP). The assessment of climate trends is based on the use of parametric and non-parametric statistical tests, such as the Mann-Kendall test, Pettitt test, and linear regression. Furthermore, the calculation of climatic aridity is performed using the De Martonne index. The results highlight a significant increase in annual average temperatures (+1.5 °C over 40 years), a decrease in annual precipitation (-15% between the periods 1984-1999 and 2000-2024), and an exacerbation of drought, with the De Martonne index changing from 5,14 to 4,75. These changes attest to an intensification of global warming in this semi-arid region and underscore the urgent need to develop comprehensive adaptation strategies to mitigate the environmental and socio-economic impacts.

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