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Climatic Oscillations Recorded in a Coastal Setting on the French Side of the English Channel
Reference
Billeaud, I., Tessier, B. and Lesueur, P. 2009. Impacts of late Holocene rapid climate changes as recorded in a macrotidal coastal setting (Mont-Saint-Michel Bay, France). Geology 37: 1031-1034.

What was done
On the southern coast of the English Channel, the authors studied offshore-derived sediments in the macrotidal setting of Mont-Saint-Michel Bay, France, where they conducted a high-resolution sequence stratigraphy analysis of the intertidal to subtidal wedge, utilizing juvenile shells, peat and organic-rich bulk sediment derived from 50 vibracores for accelerator mass spectrometry 14C dating, and where high-resolution seismic reflection data were acquired in the subtidal to lower intertidal domains.

What was learned
The work of Billeaud et al. revealed that "rapid climate changes, with ~1500-year periodicity, are recorded in the sedimentary successions that constitute the late Holocene infill of the bay," and that "the various changes reflect an increase in wave dynamics in association with Bond cold events, possibly in conjunction with long-term (1800-year periodicity) tidal cycles," as well as "storm impacts, which occur with a millennial time-scale periodicity."

What it means
The work of the three French scientists adds to the overwhelming evidence provided by other paleoclimate records that have shown, in their words, that "Holocene climate was punctuated by widespread cooling events, recurring every ~1500 500 years (Bond et al., 1997; Bianchi and McCave, 1999; Broecker, 2000; Mayewski et al., 2004; Debret et al., 2007; Allen et al., 2007)." And since this periodicity suggests that the world was fully ripe for a recovery from the last of these coolings (i.e., the Little Ice Age), 20th-century global warming is seen to be neither unusual, unnatural nor unprecedented, which latter three adjectives are routinely - but very wrongly - used by climate alarmists to suggest that the most recent upward swing of this recurrent temperature cycle was caused by anthropogenic CO2 emissions. It was not. It was merely time for the earth to naturally recover from the coldest interval of the current interglacial period, which further suggests that a good deal of warming was only to be expected.

References
Allen, J.R.M., Long, A.J., Ottley, C.J., Pearson, D.G. and Huntley, B. 2007. Holocene climate variability in northernmost Europe. Quaternary Science Reviews 26: 1432-1453.

Bianchi, G.G. and McCave, N. 1999. Holocene periodicity in North Atlantic climate and deep-ocean flow south of Iceland. Nature 397: 515-517.

Bond, G., Showers, W., Cheseby, M., Lotti, R., Almasi, P., de Menocal, P., Priore, P., Cullen, H., Hajdas, I. and Bonani, G. 1997. A pervasive millennial-scale cycle in North Atlantic Holocene and glacial climates. Science 278: 1257-1266.

Broecker, W.S. 2000. Abrupt climate change: Causal constraints provided by the paleoclimate record. Earth-Science Reviews 51: 137-154.

Debret, M., Bout-Roumazeilles, V., Grousset, F., Desmet, M., McManus, J.F., Massei, N., Sebag, D., Petit, J.R., Copard, Y. and Trentesaux, A. 2007. The origin of the 1500-year climate cycles in Holocene North-Atlantic records. Climate of the Past 3: 569-575.

Mayewski, P.A., Rohling, E.E., Stager, J.C., Karlen, W., Maasch, K.A., Meeker, L.D., Meyerson, E.A., Gasse, F., van Kreveld, S., Holmgren, K., Lee-Thorp, J., Rosqvist, G. Rack, F., Staubwasser, M., Schneider, R.R. and Steig, E.J. 2004. Holocene climate variability. Quaternary Research 62: 243-255.

Reviewed 17 February 2010