Glaciers take the heat

Declared a 'revenue village' by the Uttar Pradesh government in 1960, Gangotri, located 3240 m above sea level, has since scaled up dramatically in order to accommodate those seeking Ganga's blessing. The idol of the deity arrives in May, residing in a temple built by the long-ago Gorkhali general with imperial ambitions, Amar Singh Thapa. After the Diwali festival, the idol is carried down to its winter abode in Mukhba, near Harsil. In recent years, Gangotri has also been encountering new kinds of seekers: the scientist, environmentalist and journalist, making the climb to observe and understand the apparently faster-paced melt of glacial systems, the most obvious sign of a warming of the globe.

As a pilgrim of the latter variety, taking advantage of the easy vehicular access, I arrive in Gangotri in search of a certain swami, well known for his voluminous documentation of glacial melt. I find an ashram by the name of Ishavasyam, in the inner sanctum of which hang framed photographs of ice, snow and rock. This must be it. Over tea, the young Swami Raghavendrananda expounds on global warming, from the unprecedented high temperatures in recent years in Calcutta to the drained deep water aquifers of Punjab. After a fervent monologue on the human sullying of air and water, he bids farewell, with a visiting card and a smile that passes over to his next awaiting guests.

Later, I find another swami with another collection of photographs hanging in his cove. Whether due to his age, his modest hermitage or his temperamental decision not to meet with us for the next five hours, I come to realise that he is actually the original 'Sadhu who clicks', reference to the photographically inclined Sundarananda. He seems to be a crestfallen man after years of internalising the neglect of nature, despite personal success as a photographer and lecturer, with a museum soon to open to showcase his work. He starts right in, warning, "During the late 1800s, the glacier lip was more than nine kilometres downstream in Chirbasa. The ice flow has since receded in length, width and height. In the next 15 to 20 years, the Gangotri glacier won't exist anymore!"

The dramatic impact goes well beyond Gangotri. Swami Sundarananda shows photographs of other glaciers, taken during his own mountaineering expeditions beginning in 1956 that provide status updates of some of the glaciers in the Garhwal region: Yamunotri, gone; Vasuki, gone; Chaturangi, almost gone. Changes have also been observed in the amount of snowfall in the area. During the mid-1960s, at least four feet of snow would fall in one winter day; now the average annual snowfall in Gangotri is little more than six inches. Indeed, the reality of receding glaciers and reduced snowfall is a matter of concern whether you speak to the swami or the glaciologist.

Deformed Gaumukh
Talk about climate change has become a virtual sport since the first Assessment Report was published in 1990 by the UN's Intergovernmental Panel on Climate Change. Since then, a dizzying array of local, national and international interests have focused fierce attention on this endlessly complex issue, buttressed by a significant media engine spreading hard rumour and soft fact. Insofar as continental glaciers are visible indicators of climate change, they have become a catchall symbol and indicator for a warming climate.

On the one hand, media-generated political interest has been critical for an issue that needs immediate attention. At the same time, though, there is also the associated dearth of hard data, which has provoked a perception of sensationalism for many, coupled with a sometimes less-than-scientific tendering of proof. In a region where the impact of climate change may affect hundreds of millions of lives in the Himalaya, the Tibetan plateau to the north and the Subcontinent to the south, the response has gravitated towards adapting to the emerging emergencies, rather than a staged approach that investigates human action and thinks of ways to mitigate climate transformation. It is with an eye to further exploring these potential responses that this writer travelled to the two most-discussed retreating glaciers of Southasia: Gangotri in Uttarakhand of India, and Imja in Nepal's Khumbu region, in the shadow of Mount Everest. Besides alarm over glacial melt and its implied signs of global warming, these two areas share a history of environmental activism, primarily in the form of eco-tourism initiatives sparked by unsustainable human degradation of the surrounding ecosystem (see box).

Worldwide, despite the awe that glaciers invite, their surface area is actually not that significant. As such, their mass reacts to changes in temperature and precipitation within a matter of decades and even seasons. The linear retreat of the glacier is like a visual barometer, making their surge and retreat recognisable on a human scale. In geological terms this is especially short, particularly when one considers that the heat wave that began 15,000 years ago has yet to reach into some of the deepest layers of the Antarctic ice sheet.

As of this writing, the Gangotri glacier is a 30-km-long ice flow, part of the second-largest glacial catchment in the Himalaya, after the Siachen in the eastern Karakoram. The World Wild Fund for Nature (WWF) considers the Gangotri a 'benchmark' glacier proving that global warming is a reality. The glacier has thus found its way into PowerPoint presentations of glaciologists around the world. Images disseminated by NASA, contouring the retreat that has taken place from 1780 to 2001, likewise seem to prove the point of retreat beyond a doubt. Four thousand years ago, the source of the Bhagirathi, which evolves into the Ganga, is believed to have been near the Gangotri temple, a full 18 km downstream of the present source. During the late 1960s, the glacier was retreating at an average rate of 30 metres per year, slowing down to between 22 and 27 metres per year in more recent decades, according to a 2004 analysis by Renoj Thayyen of the National Institute of Hydrology in Uttarakhand.

Carving out the contours of the adjacent hills, the route to Gangotri glacier's snout, Gaumukh, is an easy upward incline used by many for contemplation. Moraines in the four kilometres towards Gaumukh from Bhojbhasa have been marked by the Department of Science and Technology (DST) to measure the glacier's former reach. One such marking shows that in 1966, the glacial tongue licked more than a kilometre down from its current position; in 1935, it was some two kilometres away. Finally, up ahead, the Gangotri glacier emerges behind piles of moraine residue – an almost living mass of ice, nearly 50 feet tall. At the base, water rushes out of a thundering opening. Walking atop the rock-laden ice mass, you can hear and see melting in the continuous slide of debris and trickling of water. There is clearly a powerful natural force at work here on the Gangotri; and if this power is out of balance, as is increasingly becoming clear, then the population to be hit will be one of the largest in the world.

Cryosphere up close
Glaciers are a focus of concern not only due to their sensitivity to temperature, but also because many are located relatively near to, or with direct access to, human settlement. The proximity of the Gangotri and Imja glaciers to human settlement is crucial for the interest their retreat has generated. This includes both the scattering of small permanent and semi-permanent villages in the respective areas, as well as the lucrative masses of pilgrims and tourists. The large influx of pilgrims began in Gangotri during the mid-1980s, after road and bridge construction made it easier to get there, and in 2008 there were 326,000 visitors. While the Khumbu region in Nepal, with its numerous glaciers, does not attract the pilgrims, it is the focus of overseas trekkers, of whom more than 25,000 arrived last year. Thus, the swelling lake of Imja Tso, just to the side of the main trekking route to the Mt Everest Base Camp, has not gone unnoticed.

When there is excessive snow and ice melt, water tends to collect at the base among the moraines, creating an unstable lake that could burst its dam of debris and cause devastation downhill. Such phenomena are known as Glacial Lake Outburst Floods. Of course, GLOFs, as they are commonly known, have been around as long as the glaciers themselves, and the devastation they would cause has long been one of the main motivating factors to study glacial lakes. In one of the earliest known references to GLOFs, a painting from 1601 depicts a lake on the Vernagtferner Glacier of the Austrian Otztal Alps. The glacier's surges had long blocked meltwater from glaciers further upstream, forming an ice-dammed lake known as the Rofener Eissee, sometimes reaching up to 1.5 km in length. Occasionally, the lake would burst through its ice breach, flinging a high-velocity rush of water and debris downstream, the last of which was recorded in 1848.

The Himalaya glacial lakes and their recent increase in number and size are said to be proof of the accelerating global warming. Over the past decade, glaciologists have been following the growing size of Imja Tso and other lakes. The repository of information on Himalayan glacial melt and GLOFs is the International Centre for Integrated Mountain Development (ICIMOD) in Kathmandu. According to ICIMOD scientists, Imja is the fastest-retreating glacier in Nepal, with an average melt rate of 59 metres per year between 1994 and 1998. The retreat rate was 74 metres per year from 2001 to 2006 and helped create a lake at its base. When Edmund Hillary and Tenzing Norgay were making their way up Everest during the early 1950s, the lake was nonexistent; today it has a circumference that takes at least an hour to traverse. It is not only the retreat of the glaciers that is the barometer of snowmelt, but the lakes that these receding glaciers leave behind.

The implications of increased glacial melt also go far beyond the high-altitude communities. Glacial melt is essentially 'visible proof' of global warming, whose implications are global in a complex web of inter-relationships. In addition, as glacial melt accelerates, we will see heightened river levels in the short term and decreased runoff in the longer term as the ice mass decreases, making rivers less perennial. The Himalayan ramparts are considered by some scientists as the 'water towers' of Asia. The rate of depletion of these 'water towers' will also partially depend on precipitation patterns. Apart from glaciers in the western regions of the Hindukush and on the Tibetan plateau, Himalayan glaciers generally accumulate more snow and ice in the summer than in the winter, as the southwest monsoon brings intense precipitation along the southern flanks. For glaciers where accumulation and ablation (the loss of ice and snow) primarily take place during the summer, warm temperatures intensify melting because precipitation more often occurs in liquid rather than solid form.

Locals of Khumbu have certainly been witness to the gradual changes in precipitation. Jyokraj Kulung, a porter from Cheskam, south of Khumbu, remembers marvelling over his grandfather's stories about waist-high snowfall in Dingboche, a village at an altitude of 4530 metres. Today he can only imagine what that must have been like: to see that much snow in his lifetime seems unimaginable, with most snow in recent years melting almost immediately after it fell.

Information 'white spot'
Unlike glaciers in the United States, Europe, the Arctic and the Antarctic, for which decades of data exist, accurate and consistent data go back only a few decades in the Himalaya. Glacial fluctuations have been studied since the 1950s in Asia, beginning with field investigations and aerial photography. Some long-term monitoring stations were established during the 1960s, while remote sensing (using high-resolution satellite imagery) and other more-detailed methods were only introduced during the 1990s. China remains the only country to have used ice-core extraction to research the glaciers in detail. Studies in India and Nepal, meanwhile, began later still, with the first baseline study for Nepal gathered in 2001 by a team from ICIMOD. The latter also coordinated an inventory of glaciers and glacial lakes in the Hindukush-Himalaya region in 2000-03, based on remote-sensing methods, and is currently in the process of producing an updated aggregation by 2010, which should include previously neglected ranges in Afghanistan, Assam and Arunachal Pradesh. Still, when it comes to comprehensive field studies involving long-term measurements of individual glaciers, records remain inadequate, making predictions even more problematic.

This lack of corroborated information is partially due to the difficulty of physically getting to the glaciated basins of the Himalaya, especially those higher than 4000 metres. Postulations regarding quantity of ice loss thus often involve limited selection of glaciers, rather than the region's ice masses as a whole. Out-dated national-security concerns also prevent the sharing of available information even within one country and the publicising of comprehensive analysis where it has been conducted. One long-term study by the Chinese Academy of Science, which covered China's nearly 47,000 glaciers, reported in 2004 that over the previous 24 years these ice flows had shrunk by 5.5 percent. Significant retreats have likewise been observed in individual Indian, Bhutanese and Nepali glaciers, ranging from two to almost 75 metres per year. But generally, the vast majority of research has been desk-based, using satellite imagery and computer simulations to understand broad trends.

As always, funding is a defining culprit for the scarcity of information. The Department of Hydrology and Meteorology in Nepal received a budget of USD 84,000 in 2007 for its entire operation, barely enough to pay for salaries, building maintenance and management of weather stations. The department is responsible for monitoring the climate, river and snow hydrology, as well as conducting glaciological studies. While the Planning Commission and the DST in India have allocated INR 360 million (a bit more than USD 7 million) to set up a National Centre for Field Operations and Research on Himalayan Glaciology, these plans have been slow to take off. Currently, research on glaciers is coordinated by the Himalayan Glaciology Programme of the DST.

Even with something as obvious as receding glaciers, ambiguities and exaggerations arise as to the extent of retreat. In the midst of this still-muddy science, many are urging policymakers not to overreact. D P Dobhal, of the Wadia Institute of Himalayan Geology in Dehradun, tries to put the many details of this complex subject into perspective. His response to Swami Sundarananda's cataclysmic claims about Gangotri is: "Glacial retreat is not today's phenomenon. Glaciers gain and lose: more snowfall, low melt, glacial advance; less snowfall, high melt, glacial retreat. We must consider these things before saying that glaciers will disappear."

The geologist-turned-glaciologist, Dobhal lays out the math: "Suppose a glacier is 10 kilometres long, this means 10,000 metres. If the recent rate of melting is 20 metres per year, one could even add one metre after five years due to warming, then the aggregate will come to 500 years for the glacier to fully disappear. That is if there is not much accumulation due to precipitation." Triple this number for the 30-km-long Gangotri, and the possibility of a purely rock-capped vista up from Gangotri remains far in the future, even when one accounts for more intense melting in the years ahead. And with international journals such as the New Scientist a decade ago making claims to the effect that "glaciers in the [Southasian] region will vanish within 40 years as a result of global warming," there seems good reason for Dobhal's urging to do the math first.

Of course, even the hard figures are disputed. A WWF report in 2005 maintained that Himalayan glaciers would "shrink from the present 500,000 square kilometres to 100,000 square kilometres by 2035", whereas a 2005 report by two researchers from the University of Colorado found that the total glaciated area in the Himalaya itself was no more than 100,000 sq km. As yet, no observations that account for all glaciated basins in the region exist. While there is general acceptance of glacial melt, the absence of long-term field studies and comprehensive research inevitably put off inferences on the magnitude of the melting that is taking place.

Beyond this, the sorely understudied field also continues to raise questions about the severity of the implications of glacial melt. Even the dangerous growth of Imja Tso has been disputed. When the WWF conducted a risk assessment of the lake in August 2008, the level of concern was downgraded for multiple reasons: the researchers found no seepage to weaken the moraine dam, the lake was growing in the direction of the glacier rather than towards the dam, and there was no overhanging ice mass to drop on the lake to force its dam to breach. According to a project funded by the World Bank and NASA in 2009, glacial melt in nine river basins in Nepal contributed to four percent of the total average annual water-flow, seemingly signifying that the disappearance of these glaciers could have a far lesser impact than previously assumed. Other sources of water include snowmelt, precipitation and groundwater. A full spectrum of research will clearly be required before the scientists and policymakers can claim a complete understanding of just what is taking place in the Southasian highlands, and how it will impact the populated plains of Asia.

There are those who see benefit to the sensationalising of climate change, as the only way to generate response of policy-makers who are politically pressured by a mass belief in the oncoming climate Armageddon. But there is no shirking from the fact that the study of glacial recession in the Himalaya is as yet a vague science. The gap in data-gathering led the 2007 Fourth Assessment Report of the IPCC to refer to the Himalaya as a "white spot". Indeed, while the media hype has undoubtedly led to a more aware citizenry, it has not necessarily led to a well-informed one; the whole process has perhaps even been detrimental at times. For instance, when word of potential Imja flooding first leaked through in Khumbu, some villagers living in areas designated as at risk of being hit began selling their land, often being duped to sell on the cheap. In the end, while the glaciers of the Himalaya remain the most visible and persuasive sign of global warming, ambiguities still exist as to the rate of melt and its ramifications.

Remember the local

Exaggerating climate scenarios can often incite fear and lead to a dismissal of active engagement in changing the causes of global warming. When it comes to glacial melt within the broader framework of climate change in Southasia, where climate-related natural disasters are and will increasingly be strongly felt, the tendency is logically to emphasise measures for adaptation, to deal with oncoming and upcoming crises. As a consequence, efforts to minimise GLOF risk – from early-warning systems to intrusive 'surgeries' on glacial lakes – have been implemented as and when resources permit. Adaptation efforts dominate the policy arena, as well. In the broad schema, this is not unwarranted, since the region will have to suffer many of the negative consequences of global warming. The United Nations Framework Convention on Climate Change, which sets the global overview as to how governments are to tackle climate change, includes provisions for so-called least-developed countries, which includes Bhutan, Nepal and Afghanistan, to produce a National Adaptation Programme of Action (NAPA). Yet so far, only Bhutan has submitted a NAPA of the three, in 2006, within which four of the top nine ranked projects attend to the risk posed by GLOFs.

Unfortunately, the emphasis in the climate-change discourse on managing imminent disasters has sidelined thinking on mitigation. To prevent a tap of running water from overflowing its basin, one could either lug endless buckets of water away from the source or turn the faucet off. In the same manner, while adaptation is imperative, we will be forever adapting if no investment is made to mitigate the situation. The relatively low contribution of greenhouse gases by most countries in the region makes this a hot political issue. An argument often heard is that adaptation is being pushed by the West as a palliative whereas the crux lies in reducing present carbon emissions while accepting active accountability for historical carbon emissions. According to recent estimates, India contributes five percent of the global CO2 emissions, China 16 percent, and the rest of Southasia together a minimal one percent. Therefore, insofar as atmospheric carbon dioxide remains the principal gas contributing to global warming, efforts to reduce carbon emissions by the major contributors are the primary concern.

Nonetheless, standing on this Himalayan divide between the two largest carbon emitters in the region, one must not lose sight of the need to curb carbon consumption closer to home, especially by the affluent few. Meanwhile, other regional and local considerations to minimise the human impact on climate imbalances can also be investigated – one being the regional impact of carbon soot on exacerbating glacial melt. On the local level, Gangotri and Khumbu are ideal case studies for a more organic approach, with a legacy of investing in eco-tourism and sustainable development projects that retroactively fit in the mitigation framework in that the initiatives, however modestly, balance out the carbon credits sheet. The people of Southasia and especially its scientific community, will need to force their policymakers to reframe local and national policies to include mitigation measures that not only advocate for the West, but increasingly the rich of China and India, to fulfil their global obligations of reducing carbon emissions.