Abstract

The coupled quasi-100,000 year variations in ice volume, temperature, and atmospheric CO2 during the late-Pleistocene are generally attributed to a combination of orbital forcing, ice dynamics, and ocean circulation. It has also been suggested that changes in glaciation influence CO2 emissions from arc volcanoes. In this talk the implications of changes in sea level for melt production and CO2 emissions at mid-ocean ridges are additionally explored. Although rising sea level is expected to reduce melt production and CO2 emissions at mid-ocean ridges—-suggesting a negative feedback upon deglaciation——the expression of this signal at the ocean floor may be delayed by many thousands of years. A simple model is used to illustrate that the presence of a delayed, negative feedback in CO2 emissions generally gives rise to oscillations that resemble observed glacial/interglacial variations in Pleistocene CO2 , temperature, and ice volume.

Huybers and Langmuir, Feedback between deglaciation, volcanism, and atmospheric CO2 , Earth and Planetary Science Letters, 2009 (http://www.people.fas.harvard.edu/~phuybers/Doc/volc_ice.pdf).

Other material can be found at http://www.people.fas.harvard.edu/~phuybers/