Abstrakt
There is disagreement in the Quaternary research community in how much of the marine δ(18)O signal is driven by change in ice volume. Here, we examine this topic by bringing together empirical and modelling work for Marine Isotope Stage 3 (MIS 3; 57 ka to 29 ka), a time when the marine δ(18)O record indicates moderate continental glaciation and a global mean sea level between -60 m and -90 m.
We compile and interpret geological data dating to MIS 3 to constrain the extent of major Northern Hemisphere ice sheets (Eurasian, Laurentide, Cordilleranand we find no concrete evidence of large-scale glaciation during MIS 3 that could account for the missing ~30 m of sea-level equivalent during that time. This indicates that changes in the marine δ(18)O record are driven by other variables, including water temperature.