Planning Future Research through SCAR

The 1980s also saw work on Antarctic glacial history further facilitated by SCAR, initially through a Workshop convened by Peter Webb at the SCAR meeting in San Diego (CA) in 1986 on Cenozoic Palaeoenvironments in Southern High Latitudes. From that meeting emerged a plan for a Group of Specialists to coordinate and promote research on this broad topic. This was approved by SCAR and the Group began work with a workshop on polar drilling in Columbus, OH, in 1988. This meeting reviewed a range of drilling technologies from shelf ice, sea ice and ships, as well as shallow ship-based coring. Extensive ship-based coring programmes from the 1960s using the USNS Eltanin, USCGC Glacier and more recently the R/V N.B. Palmer provided some hard won data, but typically could not penetrate beyond the hard diamictites of the Last Glacial Maximum (with rare notable exceptions, such as the Cretaceous strata cored in Ross Sea by Domack et al., 1980). Webb (1990) provides a useful review of the state of knowledge of Antarctic glacial history at this time.

At the same 1986 San Diego meeting, there was also interest in the growing body of seismic data being collected around the Antarctic margin, because of both its scientific value for Antarctic glacial history and also the political sensitivity to possible misuse. This led to the formation of the ancillary Antarctic Offshore Stratigraphy (ANTOSTRAT) Project, led by Alan Cooper (see Chapter 5). By 1990, the project had five regional working groups to organize seismic data from the five regions of the Antarctic margin, and make it available through a Seismic Data Library System (Cooper and Brancolini, 1997). However, the main goal was to use these data as the basis for coring proposals in key areas in each region in the next decade under the aegis of the ODP.

3.5.7. Insights from Deep lee Cores

While the Antarctic drilling community was now focussed on a record of icesheet history going back to the Eocene times, the ice coring community was providing a remarkable climate record of the last glacial cycle with measurements of the atmospheric gas composition and proxy temperature history from the Vostok core (Barnola et al., 1987). The saw-tooth pattern of the glacial cycle, developing slowly (tens of thousands of years) with irregularities from varied orbital forcing, and deglaciation taking place relatively quickly (thousands of years), showed a close association with eustatic sea level change for the same period (Fairbanks, 1989). This gave new impetus to the importance of understanding Antarctic Cenozoic glacial history in order to appreciate its likely response to rising CO2 emissions, which by then was coming to be seen by senior climate scientists as an imminent danger (e.g. Hansen et al., 1988; Schneider, 1989).

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