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Climatic Fluctuations Recorded in a Southeastern France Coastal Lagoon
Reference
Robert, C., Degiovanni, C., Jaubert, R., Leroy, V., Reyss, J.L., Saliège, J.F., Thouveny, N. and de Vernal, A. 2006. Variability of sedimentation and environment in the Berre coastal lagoon (SE France) since the first millennium: Natural and anthropogenic forcings. Journal of Geochemical Exploration 88: 440-444.

What was done
The authors analyzed assemblages of minerals and microfossils from a sediment core taken from the Berre coastal lagoon in southeast France (~ 43.44°N, 5.10°E) in an effort to reconstruct environmental changes in that region over the past 1500 years.

What was learned
Results of the analysis revealed three distinct climatic intervals: (1) a cold period that extended from about AD 400 to 900, (2) a warm interval between about AD 980 and 1370, and (3) a cold interval that peaked during the 16th and 17th centuries.

What it means
The climatic intervals noted above correspond, respectively, to the well-known Dark Ages Cold Period, Medieval Warm Period (MWP) and Little Ice Age, which we have discussed in numerous prior reviews on our website. So why did we choose to highlight this particular study? We did so because of two things that suggest that the MWP was likely warmer than the Current Warm Period, which directly contradicts the climate-alarmist claim that the late 20th-century was the warmest period of the past millennium due to CO2-induced global warming.

First, the team of eight researchers found evidence of a higher kaolinite content in the sediment core during the MWP, which suggests, in their words, the occurrence of "increased chemical weathering in relation to higher temperatures and/or precipitation." Second, the concentration of microfossils of the thermophilic taxon Spiniferites bentorii also peaked during the same time interval; and this finding provides additional evidence that the temperatures of that period were higher than those of the recent past.

Reviewed 14 June 2006