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A high-resolution deuterium profile is now available along the entire European Project for Ice Coring in Antarctica Dome C ice core, extending this climate record back to marine isotope stage 20.2, ∼800,000 years ago. Experiments performed with an atmospheric general circulation model including water isotopes support its temperature interpretation. We assessed the general correspondence between Dansgaard-Oeschger events and their smoothed Antarctic counterparts for this Dome C record, which reveals the presence of such features with similar amplitudes during previous glacial periods. We suggest that the interplay between obliquity and precession accounts for the variable intensity of interglacial periods in ice core records. [ABSTRACT FROM AUTHOR]

A 13-million-year continuous record of Oligocene climate from the equatorial Pacific reveals a pronounced "heartbeat" in the global carbon cycle and periodicity of glaciations. This heartbeat consists of 405,000-, 127,000-, and 96,000-year eccentricity cycles and 1.2 million-year obliquity cycles in periodically recurring glacial and carbon cycle events. That climate system response to intricate orbital variations suggests a fundamental interaction of the carbon cycle, solar forcing, and glacial events. Box modeling shows that the interaction of the carbon cycle and solar forcing modulates deep ocean acidity as well as the production and burial of global biomass. The pronounced 405,000-year eccentricity cycle is amplified by the long residence time of carbon in the oceans. [ABSTRACT FROM AUTHOR]

Presents a report on the variations in atmospheric nitrous oxide (N2O) concentration during abrupt climatic changes. Records covering the last glacial-interglacial transition and a fast climatic change during the last ice age showing that the N2O concentration changed in parallel with fast temperature variations in the Northern hemisphere; Information about the response of the environment to global climatic changes.

Reports on pollen records of deglacial sequences from northwest Nelson, New Zealand demonstrates that there was no significant temperature decline associated with the Younger Dryas in New Zealand. When the Younger Dryas (YD) occurred; Observations of vegetation change during the YD.

Reports on the findings indicating that meridonal atmospheric circulation intensity increased in the polar South Pacific and North Atlantic at the beginning of the Holocene rapid climate change event known as the Little Ice Age (LIA). How the date of 1400 A.D. was determined; How the LIA may still be effecting climate and weather patterns at the end of the 20th century; Possible causes of the LIA.