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Coastal lagoons are rarely used as paleoclimate archives because of their complex geomorphic histories, which can be affected by both climate and sea-level change. Combined foraminiferal and XRF element analysis of sediment cores from Punta de Cartas and Playa Bailen, Cuba, isolated the effects of climate change (wet vs dry) on the lagoon environments. Foraminiferal assemblages from both Punta de Cartas and Playa Bailen show increasing diversity over the past 4000 yr BP, with a prominent increase at similar to 1400-1100 yr BP. Assemblages were initially dominated by Ammonia spp. (e.g., Ammonia tepida) and Elphidium spp. (e.g., Elphidium excavatum), indicating brackish conditions, but increased miliolid species (e.g., Triloculina spp. Quinqueloculina spp.), indicate a shift to more marine conditions up-core. Correspondingly, terrigenous input to the lagoon (Fe, Ti, Ti/Ca and K) declined over the past 4000 yr BP with a flexion at similar to 1200-1100 yr BP that is likely a consequence of decreasing precipitation. Fe, Ti and K have been used as proxies for detrital erosion and transport rates in tropical and subtropical basins, with greater input during wet periods, but have rarely been applied to shallow lagoon systems. Coincident changes in the XRF and foraminiferal data indicate decreased freshwater input to the lagoon and support an inference for the onset of drier climate conditions. Similar temporal patterns in the foraminifera and XRF records from the two lagoons, which are similar to 10 km apart, suggest a regional climate influence, with increasingly arid conditions developing since the middle-Holocene (4 kyr BP). A pronounced drying over the last similar to 1200 years agrees with other climate records from the Caribbean. (C) 2015 Elsevier B.V. All rights reserved.