BBC report: Melting glaciers and changes to the River Ganges (1st November 2009)

I found this clip of a BBC report explaining how the melting Gangotri glacier (the source of the headwaters of the River Ganges) is affecting the the flow of the River Ganges and the communities that rely on the river (Figure 1). Although rather basic, it provides a brief review of the points made in my post last week about the link between melting glaciers and changes in the dynamics of rivers in the Himalayas. However, there are some overlooked generalities made in the report that are worth highlighting:

1) States that all glaciers in the Himalayas are retreating, but at different rates.

Work by Hewitt (2005) has demonstrated this statement cannot be applied to all glaciers in the Himalayas. Hewitt (2005) shows that glaciers in the Karakoram region are largely remaining static and some are advancing. This highlights the spatial complexity of glaciers within the Himalaya, and emphasises the importance of local research, as general patterns cannot be generalised across the entire region.

2) The retreat of the Gangotri glacier by 15m in 6 months.

The period of retreat described in the clip occurred during the summer months between May to October when the rates of glacier melt are at that greatest in most parts of the Himalayas. Although it visually provides a persuasive argument for the retreat of glaciers, in order to assess the significance of this rate of retreat can only be evaluated by comparison of long-term changes in the extent of the Gangotri snout.

Figure 1: Video of a BBC report on the melting Gangotri glacier and potential impacts on the River Ganges. First aired on the 1st of November in 2009 this report occurred in the weeks before the 2009 Copenhagen Summit and the release of the ClimateGate scandal where the IPCC were forced to retract their statement that all Himalayan glaciers potentially all vanishing by 2035.


Reference:
Hewitt, K. (2005) 'The Karakoram anomaly? Glacier expansion and the 'elevation effect', Karakoram Himalayas', Mountain Research and Development, 24, 4: 332-340.