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Alpine Glaciers (Especially Those of Scandinavia)
Reference
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.

References
Bergthorsson, P. 1969. An estimate of drift ice and temperature in 1000 years. Jökull 19: 94-101.

Bernabo, J.C. 1981. Quantitative estimates of temperature changes over the last 2700 years in Michigan based on pollen data. Quaternary Research 15: 143-159.

Blyth, J.R. 1982. Storofsen i Ottadalen. Unpublished Dissertation, Department of Geography, University of Cambridge, Cambridge, UK.

Campbell, I.D. and McAndrews, J.H. 1991. Cluster analysis of late Holocene pollen trends in Ontario. Canadian Journal of Botany 69: 1719-1730.

Campbell, I.D. and McAndrews, J.H. 1993. Forest disequilibrium caused by rapid Little Ice Age cooling. Nature 366: 336-338.

Crowley, T. J. and North, G.R. 1991. Paleoclimatology, Oxford University Press, New York, NY.

Dansgaard, W., Johnsen, S.J., Reeh, N., Gundestrup, N., Clausen, H.B. and Hammer, C.U. 1975. Climate changes, Norsemen, and modern man. Nature 255: 24-28.

Grimm, E.C. 1983. Chronology and dynamics of vegetation change in the prairie-woodland region of southern Minnesota, USA. New Phytologist 93: 311-350.

Grove, J.M. 1988. The Little Ice Age. Cambridge University Press, Cambridge, UK.

Henderson, E. 1819. Iceland: or the Journal of a Residence in that Island, During the Years 1814 and 1815, Wayward Innes, Edinburgh, UK.

Innes, J.L. 1985. Lichenometric dating of debris flow deposits on alpine colluvial fans in southwest Norway. Earth, Surface Processes and Landforms 10: 519-524.

Karlen, W. 1988. Scandinavian glacial and climatic fluctuations during the Holocene. Quaternary Science Reviews 7: 199-209.

Luckman, B.H. 1994. Evidence for climatic conditions between ca. 900-1300 A.D. in the southern Canadian Rockies. Climatic Change 26: 171-182.

Naftz, D.L., Klusman, R.W., Michel, R.L., Schuster, P.F., Reddy, M.M., Taylor, H.E., Yanosky, E.A. and McConnaughey, E.A. 1996. Little Ice Age evidence from a south-central North American ice core, U.S.A. Arctic and Alpine Research 28 (1): 35-41.

Payette, S., Filion, L., Gautier, L. and Boutin, Y. 1985. Secular climate change in old-growth treeline vegetation of northern Quebec. Nature 315: 135-138.

Petersen, K.L. 1994. A warm and wet little climatic optimum and a cold and dry little ice age in the southern Rocky Mountains, U.S.A. Climatic Change 26: 243-269.

Porter, S.C. and Orombelli, G. 1980. Catastrophic rockfall of September 12, 1717 on the Italian flank of the Mont Blanc massif. Zeitschrift für Geomorphologie N.F. 24: 200-218.

Porter, S.C. and Orombelli, G. 1981. Alpine rockfall hazards. American Scientist 67: 69-75.

Pringle, H. 1997. Death in Norse Greenland. Science 275: 924-926.

Smith, D.J. and Laroque, C.P. 1995. Dendroglaciological dating of a Little Ice Age glacier advance at Moving Glacier, Vancouver Island, British Columbia. Géographie physique et Quaternaire 50 (1): 47-55.

Smith, D.J., McCarthy, D.P. and Colenutt, M.E. 1995. Little Ice Age glacial activity in Peter Lougheed and Elk Lakes provincial parks, Canadian Rocky Mountains. Canadian Journal of Earth Science 32: 579-589.

Solomina, O., Haeberli, W., Kull, C. and Wiles, G. 2008. Historical and Holocene glacier-climate variations: general concepts and overview. Global and Planetary Change 60: 1-9.

Stahle, D.W. and Cleaveland, M. K. 1994. Tree-ring reconstructed rainfall over the southeastern U.S.A. during the Medieval Warm Period and the Little Ice Age. Climatic Change 26: 199-212.

Thoroddsen, T. 1905-1906. Island. Grundriss der Geographie und Geologie, Petermanns Geographische Mitteilungen, Ergänzungsband 32, Heft 152/3.

Thórarinsson, S. 1959. Um möguleika á thví ad segja fyrir næsta Kötlugos. Jökull 9: 6-18.

Thórarinsson, S. 1957. The jökulhlaup from the Katla area in 1955 compared with other jökulhlaups in Iceland. Jökull 7: 21-25.

Villalba, R. 1994. Tree-ring and glacial evidence for the medieval warm epoch and the little ice age in southern South America. Climatic Change 26: 183-197.

Reviewed 13 January 2010