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The Jazmurian Playa in southeast Iran is a sediment archive that has preserved a record of climate and environmental changes since the late Pleistocene. The late Pleistocene was dominated by sub-arid to arid climate interspersed with short periods of warm and humid conditions that impacted the vegetation cover and landscape. This study used sedimentological variations in a sediment core, supported by geochemical and mineralogical characteristics, to reconstruct climate change impacts and water-level fluctuations in the playa. These changes were inferred using grain-size data, magnetic susceptibility, total organic matter content, carbonate content, elemental concentrations, and mineralogical composition in a 14C-dated sediment core. Based on the inferred water level fluctuations in the playa, the core was divided into two major units. Unit 2 belonged to the late Pleistocene, characterized by a cold and dry climate. In contrast, Unit 1 was deposited during the Holocene, a time marked by prevailing warm and humid conditions, with short periods of intense dust storms. Since the late Holocene, the IOSM (Indian Ocean Summer Monsoon) has played a dominant role in regional climate. Water-level fluctuations related to humidity significantly influenced the sedimentological variables, including grain-size distribution, sorting, skewness, and roundness. During cold and arid conditions, the water level was low, and coarse sediments were deposited in the playa, with low organic matter content, low concentrations of Cu, Mn, P, and V, and evaporite minerals. In contrast, high organic matter content, presence of illite, and high concentrations of Cu, Mn, P, and V and low values of ICV (Index of Compositional Variability) imply a warm and humid climate during the Holocene. The paleoclimate reconstruction in the playa provides evidence about ongoing changes that are closely related to the paleohydrological conditions in this region. [ABSTRACT FROM AUTHOR]