Climate change, water balance and edaphic drought in the southern shore of the Mediterranean: case of the eastern region of Algeria

Abstract This study addresses the climatic context of the Batna region over a 30 year period, from 1990 to 2019. The methodology relies on several analyses, first the analysis of variations in annual precipitations and temperatures relative to the average. Then, the estimation of the monthly fluctuations in precipitation and temperatures by the method of comparative graphs. The statistical analysis is conducted with Mann-Kendall trend test. Finally, the estimate of the soil drought using the formulas of Thornthwaite. The follow-up of the water balance revealed that the temperature increase, combined with the precipitation deficit, led to soil drought in the Batna region, where the available water capacity fell to 20% for 30 months. In addition, precipitation has considerably decreased in winter.