Description
Paired sediment cores were collected from four locations in glacially-dominated Lake Hvítárvatn in central Iceland (64°37'N, 19°51'W) and analyzed for "multiple physical and organic matter proxies directly related to ice cap activity and paleoenvironmental conditions," which proxies included sedimentation rate, bulk density, ice-rafted debris, sediment organic matter, biogenic silica, and diatom abundance. This work revealed, as the authors describe it, that "the past two millennia are characterized by the abrupt onset of sustained cold periods at ca 550 and 1250 AD, separated by an interval of relative warmth from ca 950 to 1150 AD," and they go on to say that these two significant cold periods of landscape instability and glacial activity beginning in the 6th and 13th centuries AD "correspond to the Dark Ages Cold Period and Little Ice Age," which they make a point of noting "are separated by a relatively stable interval in Medieval times." Thus, this information clearly indicates that the MWP held sway from approximately AD 950-1150 in this particular part of the world.