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The Little Ice Age in East Antarctica
Li, Y., Cole-Dai, J. and Zhou, L. 2009. Glaciochemical evidence in an East Antarctica ice core of a recent (AD 1450-1850) neoglacial episode. Journal of Geophysical Research 114: 10.1029/2008JD011091.

What was done
The authors conducted chemical analyses of a shallow (82.5-m) ice core they obtained from "a location [7632.5'S, 7701.5'E] in the essentially unexplored area of Princess Elizabeth Land, East Antarctica," which they used to construct "a continuous, high-resolution 780-year (AD 1207-1996) glaciochemical record."

What was learned
Li et al. report that "the period of AD 1450-1850 in this record is characterized by sharply reduced snow accumulation rates and decreased concentrations of several chemical species that suffer post-depositional losses linked to very low accumulation rates." In fact, they found that "the average accumulation rate between 1450 and 1810 is nearly 80% lower than the twentieth century average," noting that "such sharply reduced accumulation suggests that the climate conditions in this region during this period of 400 years were colder than the earlier and later periods." And they correctly state that "this period of unusually cold climate conditions in the eastern Indian Ocean sector in East Antarctica coincides with the time frame of the Little Ice Age, which has been found to be a common neoglacial episode in many Northern Hemisphere locations and in a few places in the Southern Hemisphere."

What it means
If there was a Little Ice Age in Antarctica that separated the Current Warm Period from something else, that "something else" must have been the Medieval Warm Period, which is thus demonstrated by the study of Li et al. to have occurred in Princess Elizabeth Land, where Roberts et al. (2001) also found evidence for it. In addition, Li et al. report that the Little Ice Age has been demonstrated to have made its presence felt at Antarctica's Law Dome (Morgan and Van Ommen, 1997), Dronning Maud Land (Karlof et al., 2000), Northern Victoria Land (Stenni et al., 2002), and the Antarctic Peninsula (Fabres et al., 2000; Domack et al., 2001; Shevenell and Kennett, 2002). Hence, the Medieval Warm Period must have preceded the Little Ice Age at these locations as well, reconfirming the global presence of that earlier low-CO2 high-temperature period that climate alarmists are reticent to recognize, because of the implications it holds for the non-CO2-induced global warming of the 20th century.

Domack, E., Leventer, A., Dunbar, R., Taylor, F., Brachfeld, S., Sjunneskog, C. and ODP Leg 178 Scientific Party. 2001. Chronology of the Palmer Deep site, Antarctic Peninsula: A Holocene palaeoenvironmental reference for the circum-Antarctic. The Holocene 11: 1-9.

Fabres, J., Calafat, A., Canals, M., Barcena, M.A. and Flores, J.A. 2000. Bransfield Basin fine-grained sediments: Late-Holocene sedimentary processes and Antarctic oceanographic conditions. The Holocene 10: 703-718.

Karlof, L., Winther, J.-G., Isaksson, E., Kohler, J., Pinglot, J. F., Wilhelms, F., Hansson, M., Holmlund, P., Nyman, M., Pettersson, R., Stenberg, M., Thomassen, M.P.A., van der Veen, C. and van de Wal, R.S.W. 2000. A 1500-year record of accumulation at Amundsenisen Western Dronning Maud Land, Antarctica, derived from electrical and radioactive measurements on a 120-m ice core. Journal of Geophysical Research 105: 12,471-12,483.

Morgan, V. and Van Ommen, T.D. 1997. Seasonality in late-Holocene climate from ice-core records. The Holocene 7: 351-354.

Roberts, D., Van Ommen, T.D., McMinn, A., Morgan, V. and Roberts, J.L. 2001. Late-Holocene East Antarctic climate trends from ice-core and lake-sediment proxies. The Holocene 11: 117-120.

Shevenell, A. and Kennett, J.P. 2002. Antarctic Holocene climate change: A benthic foraminiferal stable isotope record from Palmer Deep. Paleoceanography 17: 10.1029/2000PA000596.

Stenni, B., Proposito, M., Gragnani, R., Flora, O., Jouzel, J., Falourd, S. and Frezzotti, M. 2002. Eight centuries of volcanic signal and climate change at Talos Dome (East Antarctica). Journal of Geophysical Research 107: 10.1029/2000JD000317.

Reviewed 15 July 2009