evidence: The Medieval Warm Period and Little Ice Age are replaced by a largely benign and slightly cooling linear trend in climate until 1900. But as is clear from a close analysis of Mann's methods, the hockey stick is formed by crudely grafting the surface temperature record of the 20th century onto a pre-1900 tree ring record. [...] Based on this proxy data drawn from 240 peer-reviewed studies, the authors offer highly convincing evidence to support the Little Ice Age and the Medieval Warm Period. As co-author Dr. Sallie Baliunas explained, "For a long time, researchers have possessed anecdotal evidence supporting the existence of these climate extremes." Baliunas notes that, during the Medieval Warm Period, "the Vikings established colonies in Greenland at the beginning of the second millennium that died out several hundred years later when the climate turned colder." And in England, she found that, "vineyards had flourished during the medieval warmth." In their study, the authors accumulated reams of objective data to back up these cultural indicators.