Abstract. Here, we establish a spatiotemporal evolution of the sea-surface
temperatures in the North Atlantic over Dansgaard–Oeschger (DO) events 5–8
(approximately 30–40 kyr) using the proxy surrogate reconstruction method. Proxy data
suggest a large variability in North Atlantic sea-surface temperatures during
the DO events of the last glacial period. However, proxy data availability is
limited and cannot provide a full spatial picture of the oceanic changes.
Therefore, we combine fully coupled, general circulation model simulations
with planktic foraminifera based sea-surface temperature reconstructions to
obtain a broader spatial picture of the ocean state during DO events 5–8. The
resulting spatial sea-surface temperature patterns agree over a number of
different general circulation models and simulations. We find that
sea-surface temperature variability over the DO events is characterized by
colder conditions in the subpolar North Atlantic during stadials than during
interstadials, and the variability is linked to changes in the Atlantic
Meridional Overturning circulation and in the sea-ice cover. Forced
simulations are needed to capture the strength of the temperature variability
and to reconstruct the variability in other climatic records not directly
linked to the sea-surface temperature reconstructions. This is the first time
the proxy surrogate reconstruction method has been applied to oceanic
variability during MIS3. Our results remain robust, even when age
uncertainties of proxy data, the number of available temperature
reconstructions, and different climate models are considered. However, we
also highlight shortcomings of the methodology that should be addressed in
future implementations.
Sub sea surface temperatures in the Polar North Atlantic during the Holocene: Planktic foraminiferal Mg/Ca temperature reconstructions
