HOLOCENE CLIMATE ANALYSES OF THE LAST 2500 YEARS AS DESCRIBED BY A MARINE SEDIMENT CORE RETRIEVED FROM JOKULFIRDIR FJORD, NW ICELAND

The Northwest continental shelf of Iceland is known to be a climatically critical area strongly influenced by global marine circulation patterns. Core B997-341 from Jokulfirdir Fjord was recovered at a water depth of 105 meters during the Bjarni Saemundsson B997 Cruise for purposes of obtaining high-resolution Holocene climate data from this area. The Jokulfirdir receives significant freshwater drainage and sediments from the Drangajokull Icecap via the Leirufjordur River System. The 220-cm long core was sampled every 2.5 centimeters and analyses illustrate sediment and water budgets for the region. Seven C-14 dates chronologically define the core as having an average sedimentation rate of about 0.09 cm/yr. Oxygen isotope analyses were performed by Kiel University on the benthic foraminifera species Nonion labradoricum. The percentage of carbonate in the sediments reflects overall marine productivity and the data from this core indicate a pronounced carbonate minima during the Little Ice Age (LIA). The carbonate record from B997-341 closely matches that from core B997-328 in another fjord on the north coast of Iceland. Results indicate that the LIA in near shore waters of Iceland was profoundly more severe than conditions during the Medieval Warm Period and also during the second millennium BP.