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Abstract. Close coupling of Iberian hydroclimate and North Atlantic seasurface temperature (SST) during recent glacial periods has been identifiedthrough the analysis of marine sediment and pollen grains co-deposited on thePortuguese continental margin. While offering precisely correlatable records,these time series have lacked a directly dated, site-specific record ofcontinental Iberian climate spanning multiple glacial cycles as a point ofcomparison. Here we present a high-resolution, multi-proxy (growth dynamicsandδ¹³C, δ¹⁸O, and δ²³⁴Uvalues) composite stalagmite record of hydroclimate from two caves in westernPortugal across the majority of the last two glacial cycles (∼220ka).At orbital and millennial scales, stalagmite-based proxies for hydroclimateproxies covaried with SST, with elevated δ¹³C,δ¹⁸O, and δ²³⁴U values and/or growth hiatusesindicating reduced effective moisture coincident with periods of lowered SSTduring major ice-rafted debris events, in agreement with changes inpalynological reconstructions of continental climate. While in many cases thePortuguese stalagmite record can be scaled to SST, in some intervals themagnitudes of stalagmite isotopic shifts, and possibly hydroclimate, appearto have been somewhat decoupled from SST.

The cave site of Lapa do Picareiro, Portugal contains a deep (~10 m) sedimentary sequence representing much of the Middle and Upper Paleolithic, with abundant animal bones, lithic/bone/shell artifacts, and charcoal/ash in hearths. A deposition model based on 49 radiocarbon ages demonstrates average sedimentation rates of 0.1–0.3 mm a⁻¹between 9 and 45 ka. Extrapolation suggests an age at the base of the excavation of 65–78 ka. The cave sediments are primarily limestone éboulis derived from roof spalling, and muddy fine sediment derived from weathered soil infiltrating through bedrock joints and crevices. Bone preservation in the cave is good and disturbance by bioturbation, dissolution, or erosional processes appears to be limited. Most sedimentological parameters vary conservatively with depth, indicating stable sediment sources over time. Several parameters show good agreement with paleoclimate records over the radiocarbon‐dated section. The cold‐arid Heinrich stadials are represented by coarse‐clast beds with little fine sediment and magnetic susceptibility minima, and mild Greenland interstadials correspond with muddy beds and sharp peaks in magnetic susceptibility. This study complements ongoing archaeological excavation at the site and confirms that the sequence has the proper age, resolution, and preservation to inform on Late Pleistocene cultural and climatic transitions.