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A Seventy-Year History of Change in the Himalayas' Raikot Glacier
Reference
Schmidt, S. and Nusser, M. 2009. Fluctuations of Raikot Glacier during the past 70 years: a case study from the Nanga Parbat massif, northern Pakistan. Journal of Glaciology 55: 949-959.

Background
The authors write that "despite the obvious importance of the Himalayan glaciers as water sources for downstream lowlands of south Asia, and despite the growing number of local and regional glacier studies, Himalayan glacier response to climate change is poorly known (Zemp and Haeberli, 2007), mainly because long-term and continuous records of glacier fluctuations are almost completely lacking for large tracts of this mountain system (Byers, 2007; Kumar et al., 2008)."

What was done
Working in the Nanga Parbat region of northern Pakistan, which constitutes the northwestern limit of the high Himalaya, Schmidt and Nusser used a multi-temporal/multi-scale approach based on historical data, repeat photography and satellite imagery to develop a 70-year history of the behavior of that region's Raikot Glacier.

What was learned
The two German scientists report that visual comparison of repeat photography indicates "relatively small rates of recession and surface changes over the last seven decades," and they say that "in the 1994 image, no significant retreat of the glacier margin can be detected in comparison with 1985." In addition, they state that "given that some well-defined large boulders remain in the same position in 2006 as in 1934, one can assume a high stability of the proglacial area and lateral moraines," which observation, in their words, "casts doubt on the catastrophic break-out flood from four new portals in 1993 or 1994 suggested by Shroder et al. (2000)," which they say their own field visits in 1993, 1994 and 1995 "did not verify."

With respect to glacier-front variations, the pair of researchers finds that "similarly to most debris-covered glaciers in the northwest Himalaya and in the nearby Karakoram, Hindu Kush and Kun Lun ranges, Raikot Glacier shows only minor retreating rates since the 1980s," and they report that "glacier fluctuations over the past 70 years are characterized by retreat between the 1930s and 1950s, a marked advance between the 1950s and 1980s, and a relatively stable situation after 1992," adding that "a general trend of reduced glacier thickness does not appear significant over the whole observation period."

What it means
Although not highlighted by Schmidt and Nusser, their results tell a much different story than the now-discredited one that was strongly promoted in the IPCC (2007) Fourth Assessment Report, further attesting to the many excursions from reality found within that pre-settled policy-driven document.

References
Byers, A.C. 2007. An assessment of contemporary glacier fluctuations in Nepal's Khumbu Himal using repeat photography. Himalayan Journal of Sciences 4: 21-26.

Kumar, K., Dumka, R.K., Miral, M.S., Satyal, G.S. and Pant, M. 2008. Estimation of retreat rate of Gangotri glacier using rapid static and kinematic GPS survey. Current Science 94: 258-262.

Shroder, J.F., Bishop, M.P., Copland, L. and Sloan, V.F. 2000. Debris-covered glaciers and rock glaciers in the Nanga Parbat Himalaya, Pakistan. Geografisca Annalar 82A: 17-31.

Zemp, M. and Haeberli, W. 2007. Glaciers and ice caps. In: Eamer, J. (Ed.). Global Outlook for Ice and Snow. United Nations Environment Programme, Nairobi, pp. 115-152.

Reviewed 8 June 2011