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Alpine Glaciers (Especially Those of Scandinavia)
Nesje, A. 2009. Latest Pleistocene and Holocene alpine glacier fluctuations in Scandinavia. Quaternary Science Reviews 28: 2119-2136.

What was done
The author compiled, assessed and evaluated "evidence of Lateglacial and Holocene glacier fluctuations in Scandinavia as deduced from ice-marginal features, marginal moraines, proglacial terrestrial and lacustrine sites, especially new information that has become available since the review paper published by Karlen (1988)."

What was learned
Nesje reports that his data compilation indicates "significant Lateglacial ice-sheet fluctuations, glacial contraction and disappearance during the early and mid-Holocene and subsequent Neoglacial expansion, peaking during the 'Little Ice Age' [italics added]," which observations, in his words, are "in good agreement with other presently glaciated regions in the world," as he says has been described by Solomina et al. (2008) and "references therein."

What it means
The Little Ice Age in Scandinavia, as in most parts of the world where glaciers were wont to form and grow during that period, was not a time of either pleasantness or plenty. In fact, it was downright depressing and dangerous, as alpine glaciers advanced in virtually all mountainous regions of the globe during that period (Luckman, 1994; Villalba, 1994; Smith et al., 1995; Naftz et al., 1996), eroding large areas of land and producing masses of debris. Like an army of tractors and bulldozers, streams of ice flowed down mountain slopes, carving paths through the landscape, moving rocks, and destroying all vegetation in their paths (Smith and Laroque, 1995).

Continental glaciers and sea ice expanded their ranges as well (Grove, 1988; Crowley and North, 1991). Near Iceland and Greenland, in fact, the expansion of sea ice during the Little Ice Age was so great that it isolated the Viking colony established in Greenland during the Medieval Warm Period, leading to its eventual abandonment (Bergthorsson, 1969; Dansgaard et al., 1975; Pringle, 1997).

Two closely associated phenomena that often occurred during the Little Ice Age were glacial landslides and avalanches (Porter and Orombelli, 1981; Innes, 1985). In Norway, an unprecedented number of petitions for tax and land rent relief were granted in the 17th and 18th centuries on account of the considerable damage that was caused by landslides, rockfalls, avalanches, floods and ice movement (Grove, 1988). In one example of catastrophic force and destruction, the Italian settlements of Ameiron and Triolet were destroyed by a rockfall of boulders, water, and ice in 1717. The evidence suggests that the rockfall had a volume of 16-20 million cubic meters and descended 1860 meters over a distance of 7 kilometers in but a few minutes, destroying homes, livestock, and vegetation (Porter and Orombelli, 1980). Other data suggest rockslides and avalanches were also frequent hazards in mountainous regions during this period (Porter and Orombelli, 1981; Innes, 1985).

Flooding was another catastrophic hazard of the Little Ice Age, with meltwater streams from glaciers eroding farmland throughout Norway (Blyth, 1982; Grove, 1988). In Iceland, flooding also wreaked havoc on the landscape when, on occasion, subglacial volcanic activity melted large portions of continental glaciers (Thoroddsen, 1905-06; Thorarinsson, 1959). Peak discharge rates during these episodes have been estimated to have been as high as 100,000 cubic meters per second - a value comparable in magnitude to the mean discharge rate of the Amazon River (Thorarinsson, 1957). During one such eruption-flood in 1660, glacial meltwater streams carried enough rock and debris from the land to the sea to create a dry beach where fishing boats had previously operated in 120 feet (36.6 m) of water (Grove, 1988); while flooding from a later eruption carried enough sediment seaward to fill waters 240 feet (73.2 m) deep (Henderson, 1819).

There is also evidence to suggest that some regions of the globe experienced severe drought during the Little Ice Age as a result of large-scale changes in atmospheric circulation patterns (Crowley and North, 1991; Stahle and Cleaveland, 1994). In Chile, for example, dendrochronology studies have revealed that the most intense droughts of the past 1,000 years occurred during this period of time (Villalba, 1994). Similar findings have been obtained from tree-ring analyses in the southeastern United States, where the most prolonged dry episode of spring drought in the last 1,000 years occurred during the mid-18th century (Stahle and Cleaveland, 1994). Elsewhere in the southwest U.S., dendrochronology data indicate that the warm and moist conditions experienced during the Medieval Warm Period gave way to progressively cooler and drier conditions during the Little Ice Age; and it is suspected that this transformation of the climate led to the demise of the Anasazi Indian civilization by reducing the area of land on the Colorado Plateau that was suitable for agriculture (Petersen, 1994). Indeed, cold temperatures and glacial advances resulted in problematic farming in many areas of the world during the Little Ice Age; and failed crops and disrupted ecosystems produced much human misery (Bernabo, 1981; Grimm, 1983; Payette et al., 1985; Campbell and McAndrews, 1991; Cambpell and McAndrews, 1993).

Consequently, and in light of all of the debilitating phenomena associated with depressed global temperatures, if there was even the slimmest of chances that the historical increase in the air's CO2 content may have contributed somewhat to the 20th-century warming that brought the planet out of this awful environmental state, it should be applauded.

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Reviewed 13 January 2010