Caractérisation isotopique des pluies en Tunisie. Essai de typologie dans la région de Sfax

Abstract

This paper determines the isotopic signature of monthly precipitation in Tunisia and highlights the main influence of air mass origin and temperature. On an event basis, this impact is confirmed and two groups can be distinguished at Sfax: (i) rain coming from Atlantic air masses that circulate in northern Africa (group I), (ii) precipitation due to atmospheric circulation on the Mediterranean Sea (group II). Mediterranean rains are enriched in oxygen-18 (−4.1 ‰), whereas the Atlantic ones show a more depleted value (−6.7 ‰). These specific signatures will be useful for groundwater tracing.