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The Medieval Warm Period and Little Ice Age off North Iceland
Reference
Knudsen, K.L., Eiriksson, J., Jansen, E., Jiang, H., Rytter, F. and Gudmundsdottir, E.R.  2004.  Palaeoceanographic changes off North Iceland through the last 1200 years: foraminifera, stable isotopes, diatoms and ice rafted debris.  Quaternary Science Reviews 23: 2231-2246.

What was done
Climatic changes over the last 1200 years were documented by high-resolution multi-proxy studies of benthic and planktonic foraminiferal assemblages, stable isotopes, and ice-rafted debris found in three sediment cores retrieved from the North Icelandic shelf.

What was learned
The authors report that "the time period between 1200 and around 7-800 cal. (years) BP, including the Medieval Warm Period, was characterized by relatively high bottom and surface water temperatures," after which "a general temperature decrease in the area marks the transition to ... the Little Ice Age."  They also note that "minimum sea-surface temperatures were reached at around 350 cal. BP, when very cold conditions were indicated by several proxies."  Thereafter, they say that "a modern warming of surface waters ... is not [our italics] registered in the proxy data," and that "there is no clear indication of warming of water masses in the area during the last decades," even in sea surface temperatures measured over the period 1948-2002.

What it means
Both the Medieval Warm Period and Little Ice Age were very real phenomena off North Iceland.  The absence of evidence for the Modern Warm Period, however, suggests that this part of the planet may still be experiencing the last vestiges of the Little Ice Age.  Clearly, not all of the Arctic has undergone the "unprecedented" recent warming that climate alarmists claim it has.  In fact, some of the Arctic has not warmed at all, either in recent years, decades or centuries.

Reviewed 2 February 2005