Aaron Putnam, a postdoctoral research scientist at the Lamont-Doherty Earth Observatory of Columbia University, is a leader of an expedition to Bhutan to examine links among climate, glaciers and water resources in the Himalaya.
Wednesday, Oct. 3
A slow morning followed our long slog to the Darlay Marpo campsite, at 4,700 meters (about 15,400 feet) above sea level. David Putnam and Paul Krusic, among others, suffered from nausea and headaches that were probably a result of a combination of dehydration and altitude. Still not all horses, and hence not all equipment, had arrived at our camp.
It turns out that confusion among horsemen led to our gear's being deposited at a camp downstream. The marginal health of our group, as well as the lack of essential equipment, prohibited us from making the final push to high camp for yet another day. However, conditions were clearer and brighter, adding a much-needed psychological boost, particularly for those who were in recovery.
In the morning, some of us worked to diagnose and repair problems that had arisen with the generator. I then took the opportunity in the afternoon to venture a few kilometers (about two miles) up valley to the edge of our field area at 5,100 meters (about 16,700 feet) above sea level.
I could still feel myself adjusting to the effects of altitude while climbing the steep morainal slope that brought me to the edge of our field area. However, as I crested the final ridge, all of my physical woes were forgotten as I witnessed, for the first time, the majestic, glacier-covered landscape of the Rinchen Zoe region.
Until that point, all of my knowledge of the area came from inspecting aerial photographs and reading painfully brief online accounts of treks through the region. And finally, after a year of planning and six days of walking uphill, I saw with my own eyes the landscape that holds the clues to unraveling the climate mysteries of Shangri La.
Directly before me lay moraine ridges peppered with massive granite boulders, signifying colder times with more extensive glacier ice. I could see the modern remnants of that former glacier in the distance; its melting terminus has since receded onto steep granite cliffs, and the resulting icefalls resemble the teeth of a dragon.
It was from this first impression that I devised later, with help from Tshewan Rigzin (of the Hydro-Meteorological Services Division), the informal name Drukso Gangri (Dragon Tooth Ice Mountain/Glacier).
After investigating the ridges of old glacial debris for roughly half an hour, I was satisfied that the integrity of the landforms and boulders would be suitable for developing a detailed map and robust chronology of past glaciation.
I then bounded back to Darlay Marpo camp. With each step downward I felt more energetic, perhaps due to a combination of increased oxygen supply and the sheer excitement of having finally seen this area that I had, until just then, only dreamed of studying. I returned to our site to report on both the scientific qualities of the field area and the sheer beauty of the region.
That evening we designed plans for the next day. Because the members of the glaciology team are faced with a very short time frame in which to complete their work, we decided that we would split into two groups the next day.
Ed Cook and Karma Tenzin would stay at Darlay Marpo to examine the high, frost-beaten juniper shrubs, while the rest of us would make our way to high camp at the mouth of Tachanggay Tso, the glacier-fed lake at the heart of our field site.
Once at high camp, Summer Rupper and Josh Maurer would work with Tshewan and Pashu Pati Ssarma, both of the Hydro-Meteorological Services Division, to erect the automatic weather station.
Meanwhile, Mike Roberts and I would venture high onto the glacier itself to scout a safe access route and outline a longitudinal transect along which Summer and Josh could implant stakes to monitor glacier melt and accumulation rates.
The next morning we executed the plan early. One shipment of gear had already been sent to our high campsite at Tachanggay Tso. Mike, Summer, Josh and I clambered up to our high campsite to assess the surroundings. It was gorgeous weather, and Drukso Gangri was illuminated from top to bottom, providing an ideal opportunity for Mike and me to scout a safe access route.
From the southern end of the lake we peered northward to the glacier. The best approach appeared to be onto the lower, melting portion of the glacier at its western end. We thought that we could access the ice by traveling along the western lateral moraine ridge that towered above the lake. The only catch was that we could not see what might lie between the uppermost portion of the lateral moraine and the glacier itself. It could be a nice bedrock bench, or it could be a deep, impassable chasm. We had no idea. The only way to find out was to see it with our own eyes.
With that, Mike and I set out for the glacier by climbing the long lateral moraine ridge that led toward the western edge of Drukso Gangri. After about an hour of boulder-hopping and scrambling, we reached an overlook that allowed us to assess the landscape between the moraine ridge and the glacier margin. To our delight, it indeed was a broad, gentle valley of glacially transported boulders draped over bedrock. There was a river gorge, but it was easily avoidable.
We meandered our way across the boulder field, and finally, at long last, reached the edge of the ice.
The lower, western edge of Drukso Gangri is a gentle glacier slope that is in complete ablation. Swirls of contorted, fine-grained debris bands are being exposed at the glacier surface.
Upon reaching the ice edge, Mike and I stepped into our harnesses, snapped on our crampons and walked onto the ice. We headed toward the lowest possible elevation that we could reach safely on the glacier, and wedged a bamboo stake into a crevasse that would mark the lower end of Summer and Josh's transect.
The ice was bare and most crevasses were visible, making navigation on the ice straightforward. We climbed upward along the glacier, marking more points, until we reached the base of what appeared to be a navigable icefall.
We ended the transect at about 5,340 meters (17,520 feet) above sea level, which accounted for nearly 100 meters of vertical relief along which Summer and Josh will measure glacier melt.
After registering GPS waypoints, Mike and I descended from the glacier and headed back to camp as darkness descended. We finally arrived at camp in a tired but euphoric mood, and we reported our success to the others. Finally, having reached our field area after six hard days of travel, we have confirmed that all aspects of the landscape will be suitable for our moraine and glacier work. Time to get to work!
Editor's Note:
Correction: An earlier version of this post had the incorrect height for the level at which Aaron Putnam and Mike Roberts marked the transect. It was 5,340 meters, not 15,340.
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