"Watch out!" came the scream from behind me. As I turned around, people were scrambling for cover when a rock, the size of a microwave, plummeted towards us. Pressing ourselves quickly against the cold wall next to us, the rock landed at our feet, smashing noisily into the icy floor. "That was close," laughed my guide next to me. The sounds of rushing water, ice cracking and falling rocks quickly reminded me of the dynamic nature of the place where I currently found myself.
I was standing inside a crevasse in the lower reaches of the Hailuogou glacier, a tongue of ice 15 km long, that plunges off the east side of the looming Mount Gongga (7,556m). Located in the Tibetan area of Garze on the southeast edge of the Tibetan Plateau, the glacier is one of China's 35,000 which cover nearly 50,000 square kilometers in the west of the country. The area has been dubbed the world's “third pole,” as a result of the significant volume of ice it contains.
This region has increasingly garnered scientists’ attention as changes in glacial cover have gradually become more and more apparent. During this time, all but a few of the glaciers on the plateau have shrunk, with the greatest retreat occurring since the 1980s, seeing shrinkage of more than 6,500 sq. km.
Flanked on either side by lush forests, the Hailuogou glacier is one of China's 8,500 monsoonal temperate glaciers which make up nearly 20 percent of the country's total glaciers. They are characterized as being found at lower altitudes of between 3,000 to 5,000 meters and are more sensitive to climate change than polar or continental glaciers.
Since the Little Ice Age, studies have revealed that the total monsoonal glacier coverage in the southeast of the Tibetan Plateau has decreased by as much as 30 percent, causing alarm in scientific circles. The Hailuogou glacier has retreated over 2 km during the 20th century alone.
"Climate warming has resulted in sustained mass loss from the Hailuogou basin glaciers through the past 45 years," according to Zongxing Li and his colleagues from the State Key Laboratory of Cryosphere Science of the Chinese Academy of Sciences. "In response to warming, glaciers in western China have been retreating since the early 20th century, and the retreat has been accelerating since the 1980s."
Over the past 150 years, temperatures have risen just 0.4 to 0.5 degrees centigrade on average in China, but this small difference has seen a remarkable change in the glaciers of the Tibetan Plateau, as knock-on effects have been seen in the region.
"The fact that the temperature is rising [on the Tibetan Plateau] almost a degree every decade is pretty worrying. It’s rising much faster than the rest of China or the rest of the world," said John MacKinnon of the EU-China Biodiversity program, who has been observing the changes on the Tibetan Plateau for the majority of his 30-year career in China. "The glaciers melting and the permafrost, the frozen water in the land, are changing the nature of the lakes on the plateau [and] the river flow on the plateau. You would think it should be getting wetter, and it is slightly getting wetter, but it is so much hotter that evaporation is terribly high, so the ground is actually getting drier. So, you have this ironic fact that although it is wetter, it’s drier."
The rain beat down on me as I climbed the valley walls above the Hailuogou glacier, trying to get a better vantage point to view the valley below me. The rain seemed to have discouraged other visitors, so I had the valley to myself for the time being. The only sound I could hear was a lone voice singing.
The singer turned out to be Alukea, a local man of the Yi minority, traditionally a nomadic people of hunters, farmers and herders found in the southwest of the country. As he approached, he handed me a handful of picked flowers. A simple but warm gesture of greeting on a cold afternoon above the glacier.
"The glacier is not the same as before," he said as we chatted, perched on the edge of the valley looking across at the river of ice beneath us. "The weather seems to get warmer every year."
As I looked at the freshly picked flowers Alukea had given me, I wondered about the effects from rising temperatures on biodiversity in these alpine regions and how quickly species would be able to adapt to this change.
Returning to the glacier the following day, I proceeded to move slowly up the valley. Cascading off the side of the mountain and flowing into the glacier below, a river originated from an area higher in the mountains, shrouded in clouds and out of view. Climbing up the side of the river, I caught sight of a figure scrambling around in the bushes next to the water. As I approached, the figure emerged clutching a plastic bag full of what appeared to be mosses. Surprised to see me, the person approached and introduced herself as a student from the nearby Chengdu South-West University of Minorities. She and her partner were biology students collecting samples of mosses for study from the upper reaches of the glacier. Monitoring alpine species like this has been key in understanding the effects on biodiversity of warming temperatures and climate change.
"The last time the world warmed rapidly--at the end of the last ice age--the retreat of species to higher, cooler regions was swift and inexorable"' explains zoologist and author Tim Flannery in his book “The Weather Makers.” "Over the course of the 20th century, mountain-dwelling species have withdrawn on average 6.1 meters up the slopes of their mountain homes per decade. This may seem a small amount of movement, but we must remember that our planet has not been warmer than it is now for millions of years, a situation that has left many ancient species clinging to the last few hundred meters of mountain peak around the world."
Change seems inevitable in many ways for these fragile alpine regions in the west of China. Holding the world's largest store of fresh water outside of the poles, the glaciers of the Tibetan Plateau feed Asia's mightiest rivers and subsequently supply water to over a billion people. Rising temperatures in this region and the management of the changing water resources will have crucial implications for all of those living downstream relying on the water from this important region