Australia: The Land Where Time Began

A biography of the Australian continent 

Sea Surface Temperature in the Long-term and Climate Change in the Australian and New Zealand region

In this paper Barrows et al. have compiled and compared data from 4 deep-sea cores that cover the last 150,000 years from the midlatitude zone of the Southern Hemisphere. The surface temperature estimates that were derived from foraminifera were recalculated and compared their results with estimates that were derived from alkenones and magnesium/calcium ratios in the carbonate from the shells of the foraminifera and with the accompanying records from sedimentology and pollen on a common absolute time scale.  They used a stack of the highest resolution records to find that first-order climate change occurs in concert with changes in insolation in the Northern Hemisphere. The extent of glaciers and inferred changes in vegetation in Australia and New Zealand vary in tandem with sea surface temperatures, indicating close links between the oceanic and terrestrial temperature. Rapid changes in temperature of the order of 6^oC in the Southern Ocean were shown to occur within a few centuries and appear to have had an important role in climate change in midlatitudes. Sea surface changes that occurred over long periods match closely proxy temperature records from Antarctic ice cores. Warm events were found to correlate with Antarctic events A1-A4, and apparently occur just prior to Dansgaard-Oeschger events 8, 12, 14, and 17 in Greenland.

Sources & Further reading

1. Barrows, T. T., S. Juggins, P. De Deckker, E. Calvo and C. Pelejero (2007). "Long-term sea surface temperature and climate change in the Australian-New Zealand region." Paleoceanography 22: PA22215.