Reference
Moros, M., Jansen, E., Oppo, D.W., Giraudeau, J. and Kuijpers, A. 2012. Reconstruction of the late-Holocene changes in the Sub-Arctic Front position at the Reykjanes Ridge, north Atlantic. The Holocene 22: 877-886.
What was done
On the basis of "new oxygen isotope data of the three planktonic foraminiferal species Neogloboquadrina pachyderma dextral coiling (d.), Globigerina bulloides and deep-dweller Globorotalia inflata, Mg/Ca-derived sea-surface temperature data on N. pachyderma d. compared with alkenone biomarker paleothermometry, coccolith abundance and species counts and diatom census data," which they derived from a sediment core extracted from Reykjanes Ridge at 58°56.327'N, 30°24.590'W in the North Atlantic, as the authors describe it, they inferred "late-Holocene trends and variability of the East Greenland Current influence on the Sub-Arctic Front in the study area."
What was learned
The five researchers - representing Denmark, France, Germany, Norway and the United States - report finding "increasingly colder millennial-scale cooling events," which were centered on 5.6, 3.8, 2.7, 1.3 and 0.3 ka, the latter and coldest of which was the Little Ice Age, while in between the third and fourth of these cold events was the Roman Warm Period, which they describe as the warmest period of the late Holocene.
What it means
Climate change is real, just like Al Gore, James Hansen and the world's other climate alarmists vehemently contend. In fact, it's the norm. And in the most recent manifestation of this change, earth's climate has shifted over the past century or so from the coldest period of the current interglacial to a significantly warmer state, but one that may still not have achieved the level of warmth characteristic of the prior Medieval Warm Period or the earlier Roman Warm Period, as suggested by the study of Moros et al., as well as the many hundreds of other such studies we have reviewed on our website. And as none of these warm-ups, as well as still earlier ones, were driven by increases in the air's CO2 content, there is no compelling data-based reason to believe that the most recent such warming of the globe has been driven by anthropogenic CO2 emissions.