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Author(s): Richard Bintanja (corresponding author) [1]; Roderik S.W. van de Wal [1]; Johannes Oerlemans [1] Marine records of sediment oxygen isotope compositions show that the Earth's climate has gone through [...]

A model of the Laurentide ice sheet was employed to study the release of massive icebergs into the North Atlantic Ocean, termed Heinrich events, and revealed that the state of the ice sheet determines the cooling effects and release events. The mass-balance computation for an ice sheet of a specific geometry suggests that the melting rate is greatly reduced during additional cooling whenever warm conditions affect a large ice sheet.

A World Without Ice by Henry Pollack Avery: 2009. 304 pp. $26 A World Without Ice opens with a strong foreword from Al Gore: the science has been done--now we [...]

The Antarctic Vostok ice core provided compelling evidence of the nature of climate, and of climate feedbacks, over the past 420,000 years. Marine records suggest that the amplitude of climate variability was smaller before that time, but such records are often poorly resolved. Moreover, it is not possible to infer the abundance of greenhouse gases in the atmosphere from marine records. Here we report the recovery of a deep ice core from Dome C, Antarctica, that provides a climate record for the past 740,000 years. For the four most recent glacial cycles, the data agree well with the record from Vostok. The earlier period, between 740,000 and 430,000 years ago, was characterized by less pronounced warmth in interglacial periods in Antarctica, but a higher proportion of each cycle was spent in the warm mode. The transition from glacial to interglacial conditions about 430,000 years ago (Termination V) resembles the transition into the present interglacial period in terms of the magnitude of change in temperatures and greenhouse gases, but there are significant differences in the patterns of change. The interglacial stage following Termination V was exceptionally long--28,000 years compared to, for example, the 12,000 years recorded so far in the present interglacial period. Given the similarities between this earlier warm period and today, our results may imply that without human intervention, a climate similar to the present one would extend well into the future.