Back to an ice-free future: Early Cretaceous seasonal cycles of sea surface temperature and glacier ice.

ABSTRACT: Global ice losses will likely continue with ongoing climate warming, culminating in an almost ice-free planet analogous to that which persisted throughout much of the Cretaceous. Despite extensive research, Early Cretaceous cryosphere responses to temperature and atmospheric P_CO2 fluctuations over short, human, timescales remain uncertain. Here, we show rapid late Valanginian (~133 million years ago) seasonal fluctuations in sea surface temperature (SST) and δ¹⁸O mainly driven by atmospheric P_CO2. Two distinctive features emerge: large seasonal variability of up to 15.9° ± 4.9°C in Southern Hemisphere mid-latitudes, comparable to that found today, a positive sea surface δ¹⁸O value related to evaporation (expres

SUBMITTER: He S 

PROVIDER: S-EPMC12047435 | biostudies-literature | 2025 May

REPOSITORIES: biostudies-literature