BOX 2.1 Cultural Importance of the Himalayas
People have traditionally revered mountains as places of sacred power and spiritual attainment, and the Hindu Kush-Himalayan (HKH) mountains play a central role in the spiritual, as well as practical, lives of millions of people (Bernbaum, 1998). It is from the Himalayas that the Ganges River, considered by Hindus to be the holiest of all rivers in India, rises and cuts its path through the valleys and gorges before it enters the plains. The Ganges River draining the southern area of the Himalaya is considered by Hindus to be both a goddess and a river, Ganga Mata (Mother Ganges; Eck, 1998, 2012), and is seen as sacred along its entire length. Many believe that bathing in the Ganges frees one from past sins and liberates the soul from the cycle of birth and death.
The glaciers have particular cultural importance as the perceived source of water for the Ganges and other rivers in the HKH. This is demonstrated by anecdotal evidence from pilgrims who bathe in rivers and lakes near the outlet of glaciers. For example, the Gangotri glacier is a traditional Hindu pilgrimage site. Devout Hindus consider bathing in the waters near Gangotri town a holy ritual.
The HKH region is also home to Mt. Kailash, in western Tibet (6,600 m in elevation), considered by many religions to be the holiest mountain in the world. This mountain is venerated by Hindus, Buddhists, Jains, Sikhs, and believers of Bonri, the ancient Tibetan religion (Peatty, 2011). For Hindus, Mt. Kailash is the heavenly abode of Lord Shiva and his consort Parvati. Tibetan Buddhists view Mt. Kailash as the pagoda palace of Demchog, the One of Supreme Bliss (Bernbaum, 2006). Mt. Kailash is considered sacred in these religions in part because it is the headwaters of four major rivers aligned in the cardinal directions: the Indus, the Brahmaputra, the Karnali (a major tributary of the Ganges), and the Sutlej (a major tributary of the Indus).
One of Nepal’s most famous places of religious pilgrimage is Gosainkunda Lake (4,400 m in elevation). Every year during the Janai Purnima festival in August, thousands of Hindu and Buddhist pilgrims travel there by foot to bathe in the holy lake. Glacial meltwater is strongly associated with the major lakes and rivers in the HKH region. Rivers, glaciers, and mountains in the HKH are intertwined with the daily activities, spiritual lives, and the cultures of the local populations. Uncertainty surrounding the health of the glaciers and the rivers and lakes resonates deeply throughout these cultures.
The major concentrations of glaciers in the high mountain area of Asia cross more than 12 mountain ranges (Dyurgerov and Meier, 2005). There are currently no complete glacier inventories, but there is general agreement on the area of the glaciers in the region (Armstrong, 2010; Bolch et al., 2012). The total glacier coverage of the HKH and the Tibetan Plateau north to the Tien Shan4 is thought to exceed 110,000 km2, with about 50,000 identifiable glaciers (Dyurgerov and Meier, 2005). Table 2.1 summarizes glacial area estimates from different sources. However, comparisons of glacial area among different studies are difficult because spatial extents are often different or not well categorized.
Recent work by Jacob et al. (2012) shows that although previous estimates of mass loss in the region ranged from 47 to 55 Gt yr-1, the rate may be closer to 4 ± 20 Gt yr-1. The gaps and discrepancies in these various reports emphasize the need for a comprehensive glacial inventory of the region. In addition, more information about how glacier area is distributed with elevation would lead to a better understanding of how much glacial area is in vulnerable low-elevation areas (i.e., below the ELA). Glacial hypsometry plots the distribution of glacial area with elevation. Bajracharya et al. (2011) have developed a glacial hypsometry for Nepal (Figure 2.3). The hypsometry shows that glacial ice ranged in elevation from about 3,200 m to 8,500 m. The highest amount of glaciated area was in the 100-m-elevation band centered around 5,400 m. Glacial area decreases with both increasing and decreasing elevation.
Detailed glacier area measurements are not available for the full study area. However, the Committee calculated the proportion of glacier area in different elevation bands for the Indus and Ganges/Brahmaputra. In both basins, the majority of glacier area is in the 5,000- to 6,000-m band (Figure 2.4), with a significant amount in the 4,000- to 5,000-m band. The Indus Basin has a slightly greater proportion of its glacier area below 4,000 m than the Ganges/Brahmaputra Basin, whereas the Ganges/Brahmaputra has a slightly greater proportion of its glacier area above 6,000 m. Although these values should be considered qualitative, they are consistent with the more rigorous hypsometry data from Nepal (Figure 2.3). The differences are small, but they suggest that glacial retreat would be more sensitive to changes in climate in the Indus Basin than in the Ganges/Brahmaputra Basin; however, this qualifies
4 A large mountain system located in Central Asia and to the north of this report’s study area.