The past 800 ka viewed through Antarctic ice cores
The later parts of the Quaternary are of particular importance for assessing out ability to understand the future operation of the Earth because the main boundary conditions are similar to those of today, and because we have a density of data that allows hypotheses to be tested rigorously. An. important source of such data is Antarctic ice cores, now extending back 800 ka, and containing signals both of climate, and of climate forcing factors. The Antarctic ice core deuterium record, representing Antarctic temperature, is one of the iconic Quaternary records. It shows, in common with other palaeoclimate records such as the marine benthic isotope stack, a dominant 100 ka periodicity of short warm interglacials and long, cold, glacial periods. There appear to be two different styles of interglacial. Within the glacials a millennial scale variability is dominant, manifested as the rapid Dansgaard-Oeschger events it? the north, and as subdued out-of-phase counterparts in the south. The trace gases, carbon dioxide and methane, also show a remarkably similar pattern to that of the climate records. They certainly played a role in amplifying small changes in insolation into large climate swings, and their signals are diagnostic of the operation of different processes in the ocean and the terrestrial biosphere.