Oxygen Isotope Analyses and Pleistocene Temperatures Re-assessed

Oxygen isotope analyses of foraminiferal tests in deep-sea cores have been interpreted as showing that the temperature of seawater in the Caribbean and equatorial Atlantic varied by as much as 6° C during glacial cycles. This evidence has now been reinterpreted, and changes in oxygen isotope composition are now said to correspond with the extraction of large amounts of water from the oceans during glacial periods and the recirculation of this water during periods when glaciers were at their present levels.