This paper aimed to study the record of the climatic variability during the last two millennia within the sebkha of Dkhila. Six climatic stages were recognized along the 104？cm core: the Warming Present (WP), the Late Little Ice Age (Late LIA), the Early Little Ice Age (ELIA), the Medieval Climatic Anomaly (MCA), the Dark Age (DA), and the Roman Warm Period (RWP). The WP stretches along the uppermost 1？cm with a high grey scale as sign of a dry climate. The Late LIA is located between 1？cm and 6？cm. The ELIA is located between 6？cm and 40？cm. The MCA spanning from 40？cm to 72？cm is marked by a sharp increase of the GS revealing a wet period. The DA appears along the part between 72？cm and 84？cm; a shift from light to dark sediments is recorded. The RWP appears between 84？cm and 104？cm. Based on the grain size distribution, two low frequency cycles were identified indicating radical global changes of climatic conditions, the differential tectonics, and the groundwater fluctuations. On the other hand, high frequency cycles indicate local modifications of the climatic conditions. 1. Introduction It was previously proven [1–4] that the sebkha Dkhila (as part of the sebkha Sidi El Hani) is dominated by a hydrogeological basin feeding this depression by salty water. Consequently, the hydrogeological context remains stable regardless of the climatic change. In such a case, the playa would not record the climatic variability because the high salinity imposed by coming up of saline water does not radically change with respect to climatic changes. At the level of the watershed surrounding the depression, previous investigations [5] showed the outcrop of wet aeolian sediments mainly dominated by groundwater involvement rather than the climatic variability. Subsequently, it is not evident to find an obvious record of climate changes within the watershed. The aim in this paper is to overcome these handicaps and to infer the climatic variability during the last two millennia based on the visual description of cores, the magnetic properties, and the grain-size distribution. 2. Study Area The sebkha of Dkhila is part of the sebkha of Sidi El Hani, which is in turn part of the system Mechertate-Chrita-Sidi El Hani. Though it has always been treated as a single unit, the sebkha of Sidi El Hani as such is actually made up of three communicated playas; from north to the south, one finds the playas of Sidi El Hani (sensu stricto), of Souassi Sou, and of Dkhila (Figure 1). The sebkha of Mhabeul is located in the southeast of Tunisia (Figure 1). It is an inland saline
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