Marine Isotope Stage 11

MIS 11 is characterized by overall warm sea-surface temperatures in high latitudes, strong thermohaline circulation, unusual blooms of calcareous plankton in high latitudes, higher sea level than the present, coral reef expansion resulting in enlarged accumulation of neritic carbonates, and overall poor pelagic carbonate preservation and strong dissolution in certain areas.

In fact, during periods of both eccentricity and precession minima, even small variations in total insolation might lead the control of climate to greenhouse gasses, in particular CO2.

Another explanation for the presence of barrier-reef tracts at low latitudes during MIS 11 is that tropical continental shelves were (at least partly) flooded in response to a major marine transgression (see below).

Beach deposits in Alaska, Bermuda and the Bahamas, as well as uplifted reef terraces in Indonesia, suggest that global sea level reached as much as twenty metres above the present.

[5][6][7] δ18O records show isotopic depletions that are consistent with a sea-level highstand, but temperature effect cannot be confidently disentangled from glacioeustasy.

[8] In contrast to most other interglacials of the late Quaternary, MIS 11 cannot be straightforwardly explained and modelled solely within the context of Milankovitch forcing mechanisms.

The sustained interglacial warmth may have lasted as long as it did, because orbital eccentricity was low and the amplitude of the precessional cycle diminished, resulting in several fewer cold substages during this period and perhaps also induced abrupt climate change at MIS 12–11 transition, the most intense of the past 500 kyrs.