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The Medieval Warm Period and Little Ice Age on the Faroe Islands
Roncaglia, L.  2004.  Palynofacies analysis and organic-walled dinoflagellate cysts as indicators of palaeo-hydrographic changes: an example from Holocene sediments in Skalafjord, Faroe Islands.  Marine Micropaleontology 50: 21-42.

What was done
The author analyzed variations in organic matter deposition from approximately 6350 cal yr BC to AD 1430 in a sediment core extracted from the Skalafjord, southern Eysturoy, Faroe Islands in an attempt to assess climatic conditions in that part of the North Atlantic from the mid- to late-Holocene.

What was learned
Roncaglia reports that an increase in "structured brown phytoclasts, plant tissue and sporomorphs in the sediments dating to ca. AD 830-1090 indicate increased terrestrial influx and inland vegetation supporting the idea of improved climatic conditions" during that time period, while similarly noting in another place that "the increase in the amount of structured brown phytoclasts, leaf and membranous tissue and sporomorphs indicated increased inland vegetation probably related to improved climatic conditions and/or the presence of cultivated crops on the islands."  In addition, she reports that high "total dinoflagellate cyst concentration and increased absolute amount of loricae of tintinnid and planktonic crustacean eggs occurred at ca. AD 830-1090," concluding that these observations "may suggest increased primary productivity in the waters of the fjord (Lewis et al., 1990; Sangiorgi et al., 2002)."

The "amelioration of climate conditions" that promoted the enhanced productivity of both land and sea at this time, in the words of Roncaglia, "may encompass the Medieval Warm Period in the Faroe region," and indeed it does, for the data of Esper et al. (2002) show, in their words, that the warmest portion of the Medieval Warm Period "covers the interval 950-1045, with the peak occurring around 990."

Thereafter, Roncaglia reports an increased concentration of certain organisms at about AD 1090-1260 that she says "suggests a cooling, which may reflect the beginning of the Little Ice Age."  This finding, too, is in complete harmony with the findings of Esper et al., which show a dramatic drop in temperature over this period.

What it means
Evidences for both the Medieval Warm Period and Little Ice Age show up strong and clear in the sediments of a Faroe Island fjord, demonstrating that even at sea, these major recurring extremes of cyclical Holocene climate make their presence felt to such a degree that they significantly influence both aquatic and terrestrial primary production (the latter in places where small areas of land rise above the ocean surface).

We should also note, in this regard, that both the Medieval Warm Period and Little Ice Age, although clearly detected in studies conducted all around the world [see Medieval Warm Period and Little Ice Age in our Subject Index] are nowhere to be seen in the infamous "hockeystick" temperature history of Mann et al. (1998, 1999), which is the weapon of choice wielded by climate alarmists in their crusade to convince the world to forsake fossil fuels.  Clearly, the day of reckoning cannot be far off, when they will be forced to admit the error of their ways.

Esper, J., Cook, E.R. and Schweingruber, F.H.  2002.  Low-frequency signals in long tree-ring chronologies for reconstructing past temperature variability.  Science 295: 2250-2253.

Lewis, J., Dodge, J.D. and Powell, A.J.  1990.  Quaternary dinoflagellate cysts from the upwelling system offshore Peru, Hole 686B, ODP Leg 112.  In: Suess, E., von Huene, R., et al. (Eds.), Proceedings of the Ocean Drilling Program, Scientific Results 112.  Ocean Drilling Program, College Station, TX, pp. 323-328.

Mann, M.E., Bradley, R.S. and Hughes, M.K.  1998.  Global-scale temperature patterns and climate forcing over the past six centuries.  Nature 392: 779-787.

Mann, M.E., Bradley, R.S. and Hughes, M.K.  1999.  Northern Hemisphere temperatures during the past millennium: Inferences, uncertainties, and limitations.  Geophysical Research Letters 26: 759-762.

Sangiorgi, F., Capotondi, L. and Brinkhuis, H.  2002.  A centennial scale organic-walled dinoflagellate cyst record of the last deglaciation in the South Adriatic Sea (Central Mediterranean).  Palaeogeography, Palaeoclimatology, Palaeoecology 186: 199-216.

Reviewed 15 September 2004