Weakened AMOC related to cooling and atmospheric circulation shifts in the last interglacial Eastern Mediterranean.
Elan J LevyHubert B VonhofMiryam Bar-MatthewsAlfredo Martínez-GarcíaAvner AyalonAlan MatthewsVered SilvermanShira Raveh-RubinTami ZilbermanGal YasurMareike SchmittGerald H HaugPublished in: Nature communications (2023)
There is limited understanding of temperature and atmospheric circulation changes that accompany an Atlantic Meridional Overturning Circulation (AMOC) slowdown beyond the North Atlantic realm. A Peqi'in Cave (Israel) speleothem dated to the last interglacial period (LIG), 129-116 thousand years ago (ka), together with a large modern rainfall monitoring dataset, serve as the base for investigating past AMOC slowdown effects on the Eastern Mediterranean. Here, we reconstruct LIG temperatures and rainfall source using organic proxies (TEX 86 ) and fluid inclusion water d-excess. The TEX 86 data show a stepwise cooling from 19.8 ± 0.2° (ca. 128-126 ka) to 16.5 ± 0.6 °C (ca. 124-123 ka), while d-excess values decrease abruptly (ca. 126 ka). The d-excess shift suggests that rainfall was derived from more zonal Mediterranean air flow during the weakened AMOC interval. Decreasing rainfall d-excess trends over the last 25 years raise the question whether similar atmospheric circulation changes are also occurring today.