NOAA/WDS Paleoclimatology - Northern Caribbean Stalagmite Stable Isotope Data during the Last Deglaciation

Marking the transition between the last glacial and Holocene, the last deglaciation featured rapid climate shifts including Heinrich event 1 and the Bølling–Allerød. This study presents the highest-resolution, continuous hydroclimate proxy records of this interval from the tropical Americas based on a precisely dated Cuban stalagmite. The records span 17.6–14.3 thousand years before present, revealing persistent interannual to multidecadal rainfall variability, attributed to El Niño-Southern Oscillation and Atlantic Multidecadal Variability. Broader centennial to millennial-scale trends are linked to major climate events. We observe peak aridity in western Cuba during Heinrich event 1.1 and 1.2 (~16.2 and ~15.1 thousand years before present), with preceding dry periods within chronological uncertainty, suggesting synchronicity. Wetter conditions and increased growth rates follow during the Bølling–Allerød. Model-based rainfall estimates support these results. Our proxy data highlight the dynamic nature of tropical hydroclimate, demonstrating wet and dry conditions fluctuate across timescales, despite climate state.