North Atlantic Subtropical High forcing of Atlantic Warm Pool hydroclimate variability on millennial to orbital timescales.

ABSTRACT: Orbital-scale variations in insolation are widely considered to drive tropical and monsoonal rainfall, with higher summer insolation linked to stronger precipitation. Here, we present a precisely dated speleothem record from Cuba that reconstructs Atlantic Warm Pool (AWP) hydroclimate over the past 129,000 years and challenges this paradigm. Instead, we identify a previously unrecognized link between AWP hydroclimate and the North Atlantic Subtropical High (NASH) operating on millennial to orbital timescales. During intervals of high summer insolation coupled with cooler tropical North Atlantic sea surface temperatures (SSTs), NASH strengthens and expands westward, reducing rainfall across the AWP. This SST-NASH coupling amplified precessional-scale hydroclimate variability between 130 and

SUBMITTER: Li H 

PROVIDER: S-EPMC12662202 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature