Variability of sea surface temperature regulated millennial-scale transition of hydroclimate in mid- and low-latitude Asia
Journal
Palaeogeography, Palaeoclimatology, Palaeoecology
Journal Volume
689
Start Page
113682
ISSN
0031-0182
Date Issued
2026-05
Author(s)
Abstract
The climatic transition during Marine Isotope Stage (MIS) 5b/5a represents an ‘unfinished ice age termination’. However, it remains unclear whether mid- to low-latitude Asian hydroclimate responded synchronously to high-latitude forcing during this period, as observed during Terminations I and II. Here we present new absolutely-dated stalagmites records from Baluk Cave in mid-latitude westerlies Asia and compare them with speleothem records across a broad latitudinal gradient in Asia. The replicated δ18O and δ13C records from Baluk Cave, covering 101.9 to 78.3 thousand years ago (ka BP, relative to 1950 CE), exhibit depletions of approximately 2.4‰ and 3.0‰, respectively, across the MIS 5b/5a transition. This event occurred between 87.2 ± 0.5 ka BP and 84.1 ± 0.4 ka BP, lasting about 3.1 ka is consistent within dating uncertainties with the duration inferred from Greenland ice core δ18O (∼2.9 ka) and global sea level/high-latitude ice volume change (∼3.0 ka). In contrast, the transition is recorded as longer in stalagmite records from eastern China (∼4.2–4.4 ka) and northern Borneo (∼5.2 ka), indicating a progressively lengthened duration across the transition. We attribute this spatial pattern to differential hydroclimate influences associated with sea surface temperature (SST) variability and corresponding shifts in moisture transporting from the North Atlantic, the Bay of Bengal, and the Eastern Tropical Pacific. This aligns with SST-driven wetland development in mid- to low-latitudes and global methane release, as evidenced by similar amplitudes of hydroclimate and methane changes during the MIS 5b/5a transition. Our findings highlight the varied terrestrial hydroclimatic responses to oceanic changes under rapid warming conditions.
Subjects
Asian climate sub-systems
Millennial-scale transition
Sea surface temperature modulation
Spatial hydroclimate response
Speleothem records comparison
Publisher
Elsevier BV
Type
journal article