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A Little More on the History of Climate Change in the Arctic
Reference
Miller, G.H., Brigham-Grette, J., Alley, R.B., Anderson, L., Bauch, H.A., Douglas, M.S.V., Edwards, M.E., Elias, S.A., Finney, B.P., Fitzpatrick, J.J., Funder, S.V., Herbert, T.D., Hinzman, L.D., Kaufman, D.S., MacDonald, G.M., Polyak, L., Robock, A., Serreze, M.C., Smol. J.P., Spielhagen, R., White, J.W.C., Wolfe, A.P. and Wolff, E.W. 2010. Temperature and precipitation history of the Arctic. Quaternary Science Reviews 29: 1679-1715.

What was done
In the words of the 23 researchers who produced the massive review paper, they provided "an overview of the evolution of climate from the hot-house of the early Cenozoic through its transition to the ice-house of the Quaternary, with special emphasis on the anomalous warmth of the middle Pliocene, early Quaternary warm times, the Mid Pleistocene transition, warm interglaciations of marine isotope stages 11, 5e, and 1, the stage 3 interstadial, and the peak cold of the last glacial maximum."

What was learned
What is especially interesting about the great thermal transition of the earth from "the hot-house of the early Cenozoic" to "the ice-house of the Quaternary," is the fact that Miller et al. find that "Late Holocene cooling reached its nadir during the Little Ice Age (about 1250-1850 AD), when sun-blocking volcanic eruptions and perhaps other causes added to the orbital cooling, allowing most Arctic glaciers to reach their maximum Holocene extent."

What it means
The only point we wish to make about Miller et al.'s findings is that the post-Little Ice Age warming of the earth -- within which the planet is still embedded -- started from the very coldest portion of the current interglacial, which has itself been the coldest of the last five interglacials, with the four interglacials that preceded the Holocene being, on average, more than 2°C warmer (Petit et al., 1999). Hence, one would think it quite plausible that starting from such a cold point in planetary history, a truly phenomenal natural warming would not be totally unexpected. Yet in another paper published in the very same issue of Quaternary Science Reviews, White et al. (2010) report that "thus far, human influence [which is claimed by climate-alarmists to be the primary cause of what they refer to as the recent "unprecedented" warming of the globe] does not stand out relative to other, natural causes of climate change." And this, in turn, suggests that post-Little Ice Age warming could have been even more dramatic than what has occurred to date and still not be evidence of anything unusual or unnatural, as in anthropogenic-induced, because it is only to be expected that the earth would warm considerably from such an unusually cold starting point as the Little Ice Age was.

References
Petit, J.R., Jouzel, J., Raynaud, D., Barkov, N.I., Barnola, J.-M., Basile, I., Bender, M., Chappellaz, J., Davis, M.., Delaygue, G., Delmotte, M., Kotlyakov, V.M., Legrand, M., Lipenkov, V.Y., Lorius, C., Pepin, L., Ritz, C., Saltzman, E. and Stievenard, M. 1999. Climate and atmospheric history of the past 420,000 years from the Vostok ice core, Antarctica. Nature 399: 429-436.

White, J.W.C., Alley,R.B., Brigham-Grette, J., Fitzpatrick, J.J., Jennings, A.E., Johnsen, S.J., Miller, G.H., Nerem, R.S. and Polyak, L. 2010. Past rates of climate change in the Arctic. Quaternary Science Reviews 29: 1716-1727.

Reviewed 1 December 2010