*3.2.2.2 Ombrothermal diagram of Bagnouls and Gaussen*

The analysis of the various ombrothermal curves (**Figure 5**) of the stations compared between the two periods (1913–1938) and (1990–2014), allows us to observe a period of drought varies from 5 to 7 months or more (from the month from June to September) in the resorts of the northern part of the region (steppe plains: Mécheria and Naâma). On the other hand, in the central part of the region (Saharan Atlas: Aïn Sefra), it has a fairly prolonged period of drought that varies

**Figure 5.** *Ombrothermal diagrams of the study stations.*

from 10 to 11 months (from March until the end of November). Thus, a fairly short wet period; varies from 4 to 6 months for stations in the steppe space, from one month for stations in the Atlas mountainous space and zero for stations in the Saharan domain.
