Dave Breashears has an article at Yale Environment 360 on the melting Himalayan icecap - Tracking the Himalaya’s Melting Glaciers.

For those who know the Himalaya well — I have climbed to the summit of Mount Everest five times in the past three decades — the warming of this great mountain chain is something that we have come to experience personally. The Sherpas who live atop “the roof of the world” and the climbers who often return are acutely aware of how much temperatures have risen at high altitudes in recent years, and how extensively the snow and ice on the massive Himalayan glaciers has thinned and retreated.

But it wasn’t until 2007, when I went back to Everest as part of a documentary for the Public Broadcasting Service series, Frontline, that I fully grasped the magnitude of the melting in this region, often called “The Third Pole” because of the massive volumes of ice in the Himalaya and the Tibetan Plateau. Trekking in Tibet, not far from the northern slope of Mount Everest, I carried with me a black-and-white photograph taken by the great English mountaineer, George L. Mallory, in 1921. It showed the ice-encrusted north face of Everest and, below it, the great river of ice known as the Main Rongbuk Glacier, flowing in a sweeping, S-shaped curve down a broad, stony valley.

Eighty-six years after Mallory took that photograph, I sat in the exact spot where he had snapped his iconic picture. Pulling out his photo, I was stunned by the changes that had swept over this region. The wide river of ice had retreated more than half a mile, leaving a field of separated ice pinnacles melting into the rocky ground. In the distance, the ice streams on Everest’s flank also had shrunk, exposing more of the mountain’s dark face.

It was at that moment I decided to proceed with the project whose results are visible in the accompanying photographs. The Glacier Research Imaging Project, which I helped found, has retraced the steps of some of the world’s greatest mountain photographers as they took pictures — many of them not previously published or displayed — over the past 110 years across the Himalaya and the Tibetan Plateau. I then returned to those same vantage points and took photographs that bear witness to the rapid warming of the Himalaya and the swift retreat of its glaciers. The result is an exhibition — “Rivers of Ice: Vanishing Glaciers of the Greater Himalaya” — a collaboration with the Asia Society Center on U.S.-China Relations and now on display at the Asia Society Museum in New York through Aug. 15.

These then-and-now pictures have a powerful effect on the viewer, one that I hope will bring home the reality — and serious consequences — of global warming. Gazing at Italian photographer Vittorio Sella’s 1899 picture of the Jannu Glacier in Nepal — a huge ice tongue filling a valley — and then comparing it to my 2009 photo, in which the glacier has disappeared, creates a profound sense of unease.

And we should be uneasy. The loss of these frozen reservoirs of water will have a huge impact, as the glaciers provide seasonal flows to nearly every major river system in Asia. From the Indus, Ganges, and Brahmaputra in South Asia, to the Yellow and Yangtze Rivers in China, hundreds of millions of people are partially dependent on this vast arc of high-altitude glaciers for water. As the glaciers recede and release stored water, flows will temporarily increase. But once these ice reservoirs are spent, the water supply for a sprawling, overpopulated continent will be threatened, and the impacts on water resources and food security could be dire.

TreeHugger has a post on some of the issues surrounding hydro power in the Himalayas - Scientist's Hunger Strike Halts Work on Himalayan Dam.

The near-death of one of India’s most distinguished scientists has halted work on a major hydroelectric dam in the Himalayas. Professor AD Agarwal, 77, former dean of the Indian Institute of Technology Delhi at Kanpur, has been on hunger strike for 38 days in protest against a project that would dam the waters of a Ganges tributary.

"The water ... is not ordinary water to a Hindu. It is a matter of the life and death of Hindu faith," Agarwal said, before beginning his fast in January.

This is his second fast in the past year, which he called off last week only after the Indian government agreed that it would look into electricity generation that would not impede the flow of the holy Ganges. The river must run free in order to maintain its sacred status.

However, this dam project is only one of the hundreds planned to for the Himalayan foothill regions of India, Nepal, Bhutan and Pakistan. The power needs of these nations are rising, but according to a recent report by the NGO International Rivers, many are being carried out with little environmental assessment.

"If all the planned capacity expansion materializes, the Himalayan region could have the highest concentration of dams in the world. The dams' reservoirs, tunnels, transmission lines and related works will destroy thousands of houses, rivers, forests, spiritual sites and even parts of the highest highway in the world, the Karakoram highway," says Shripad Dharmadhikary, one of South Asia's leading water and energy experts and authors of the report, titled "Mountains of Concrete".

"Damming and diversion of [Himalayan] rivers will severely disrupt downstream flows, impacting agriculture and fisheries and threatening livelihoods of entire populations," warned Dharmadhikary.

The report also cautions that climate change and the melting of the Himalayan ice cover would reduce the anticipated amount of electricity generated. As the glaciers melt, the initial increase of water flow will later decrease, as the rivers’ source disappears.

The report points out that "[t]he impact of global warming is already being felt much more in the Himalayas than in other parts of the world. This is resulting in the accelerated melting of glaciers and the depletion of the massive water store of the region. There are real fears the snow-covered mountains [will turn] into bare, rocky mountains. As glaciers melt, water in the rivers will rise, and dams will be subjected to much higher flows, raising concerns of dam safety.”

Renewable Energy Access has an interesting article on introducing electricity, on a small scale, into remote Himalayan villages (and if you've ever spent time trekking you'd know this would be a welcome advance out of the middle ages) - A mountain to climb? How pico-hydro helps rural development in the Himalayas.

Example after example of development projects worldwide have shown that local people have to grow into technological and subsequent behavioural changes slowly, for the simple, and perhaps obvious – but rarely admitted – fact that traditions and cultures change much more slowly than new technologies can be introduced. Project planners, in collaboration with local people, have to understand and openly discuss the local cultural milieu, attitudes toward change and the various factors that may predict the ability of each householder to accept and integrate new technologies into their daily lives.

The first time that an electrification system is introduced into a community, a step-by-step approach needs to be taken, starting with minimal, low-level energy services, initially providing indoor lighting only.

Such an approach cuts down on equipment size and weight, saves on infrastructure and transport costs, and increases the chance that local people’s participation will be effective and sustainable. Because the step-by-step approach begins small, it also means that misuse of the system has a relatively small and easily addressed set of consequences. It is much easier to teach people who are not familiar with the basic concepts behind the electrification technology how to use, maintain, and trouble-shoot simple, small systems than large, complex ones. Futhermore, through the participatory planning, building and installation of the rural electricification system with local people, villagers learn new skills and competencies, and develop a strong sense of ownership for the new technology. That allows a more seamless transfer of the project to the local community, which is considerably better prepared and able to run and maintain the system.

Starting small – pico-hydro

The basic village electrification system is a small, embedded power generation unit just sufficient for minimal lighting purposes, utilizing and converting the locally available, renewable energy resources. A typical project is a pico-hydro power plant installed in the village of Kholsi in December 2006. This machine generates 1.1 kW at a maximal water flow of 83 litres/s, with a negative head and a conical draft tube of 2.7 metres long. Working in the pico range means that the chosen lighting technology’s energy demand must be small. Therefore, the ISIS/RIDS-Nepal project, in collaboration with the local Nepali company Pico Power Nepal (PPN), developed white light emitting diode (WLED) lamps, each lamp holding 12 diodes (Nichia NSPW510CSE), with the unit consuming just over 1 W. These lamps are almost unbreakable, and last more than 50,000 hours, some 20 years if used for 7 hours a day.

The entire hydro power plant infrastructure, including the power house and the water canals, are built with locally available materials such as stones and wood, provided by villagers as part of their voluntary contribution to the project. In addition to providing these materials, individuals from every household in the village contributed labour and skilled assistance to the building and installation process.

Buy-in, participation and local sense of ownership were prioritized and openly acknowledged by project participants. While these issues are not a guarantee for long-term sustainability, they are important steps in the direction of a new paradigm of development.

At the completion of the project, villagers were proud of their achievement and described a strong sense of ownership in the entire endeavour. This stood in stark contrast to a hydro scheme several villages to the north, which was conceived of, designed by and implemented by foreign aid workers. Few, if any, local people were involved in a buy-in to the system that could have been achieved by contributing materials or labour of their own accord, nor, according to villagers in that region, were any local people trained on the maintenance of the system. It quickly fell into disrepair.

Kholsi village has 67 homes and one school, each house now has three WLED lamps, while schoolchildren in class read under an additional nine. A total of 210 WLED lamps are supplied.

The generator’s 225 V AC output is transformed to 615 V AC, travels via an armoured underground copper cable to the village, and is again transformed to 225V AC. Upon realizing that householders’ usage of the system for lights consumes a maximum of only 250 W at any time, the system was modified so that 850 W or more can be diverted full-time by a specially developed electronic load controller (ELC) to a water heater. This heats water in a 500 litre plastic tank that is insulated with pine needles and nestles within a larger, 1000 litre plastic tank.

The warm/hot water generated by this system is used for showering, improving hygienic conditions. It can also be used to prepare meals, reducing firewood consumption even more than already reduced by use of efficient smokeless metal stoves also installed in each family home as part of the ‘Family of four’ HCD approach.

From small acorns, mighty oaks

Experience in the field shows that in the context of remote and impoverished mountain villages in Nepal, small power generation systems are on a locally comprehensible, locally sustainable scale, and are therefore highly suitable for such communities, at least as a first step in a rural village electrification process. ...