Centennial-scale surface hydrology off Portugal during marine isotope stage 3: Insights from planktonic foraminiferal fauna variability

Planktonic foraminiferal oxygen isotope analysis by ion microprobe technique suggests warm tropical sea surface temperatures during the Early Paleogene

[1] Cool tropical sea surface temperatures (SSTs) are reported for warm Paleogene greenhouse climates based on the dO of planktonic foraminiferal tests. These results are difficult to reconcile with models of greenhouse gas–forced climate. It has been suggested that this “cool tropics paradox” arises from postdepositional alteration of foraminiferal calcite, yielding erroneously high dO values....

Tropical North Atlantic Subsurface Warming Events as a Fingerprint for AMOC Variability During Marine Isotope Stage 3

The role of Atlantic Meridional Overturning Circulation (AMOC) as the driver of Dansgaard-Oeschger (DO) variability that characterizedMarine Isotope Stage 3 (MIS 3) has long been hypothesized. Although there is ample proxy evidence suggesting that DO events were robust features of glacial climate, there is little data supporting a link with AMOC. Recently, modeling studies and subsurface temper...

Millennial-Scale Interaction between Ice Sheets and Ocean Circulation during Marine Isotope Stage 100

Waxing/waning of the ice sheets and the associated change in thermohaline circulation have played an important role in global climate change since major continental ice sheets appeared in the northern hemisphere about 2.75 million years ago. In the earliest glacial stages, however, establishment of the linkage between ice sheet development and ocean circulation remains largely unclear. Here, we...

Ice-free conditions in Fennoscandia during Marine Oxygen Isotope Stage 3?

This report concerns a study which was conducted for SKB. The conclusions and viewpoints presented in the report are those of the author and do not necessarily coincide with those of the client. Preface This document contains information on the Weichselian glacial history, specifically of conditions during Marine Isotope Stage (MIS) 3, the period preceding the Last Glacial Maximum. The informat...

Quantifying the periodicity of Heinrich and Dansgaard–Oeschger events during Marine Oxygen Isotope Stage 3