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Third Pole Challenges

2016-01-27ByYuLintao

Beijing Review 2015年49期

By+Yu+Lintao

As the globes Third Pole, changes in the Tibetan Plateaus environment are closely linked to the evolution of the environment and ecosystem of the world, and Eurasia in particular.

The Hindu Kush-Himalayan region spans an area of more than 4.3 million square km in China, Afghanistan, Bangladesh, Bhutan, India, Myanmar, Nepal and Pakistan. The region stores more ice and snow than anywhere else in the world outside the polar regions, hence its name: The Third Pole. According to the International Center for Integrated Mountain Development(ICIMOD), the area contains the worlds tallest mountains, including all 14 peaks above 8,000 meters, is the source of 10 major rivers, and forms a “formidable global ecological buffer.”

However, a recent report on environmental change of the worlds highest plateau published by the Institute of Tibetan Plateau Research(ITPR) under the Chinese Academy of Sciences(CAS) showed that as a result of global warming and human activity, the Tibetan Plateau is becoming both warmer and moister, and that natural disasters are on the rise.

Fortunately, the report also showed that despite dark projections for the long-term effects of climate change, the Tibetan Plateau remains one of the worlds cleanest expanses.

A warming plateau

The environmental assessment report reviewed the changes on the Tibetan Plateau over the past 2,000 years and previewed its environments evolution in the upcoming century. This was achieved through the efforts of more than 70 specialists from China, the United States, Sweden, Canada and several other contributors.

Data gathered by the report showed that the Tibetan Plateau has become more hot and humid, particularly over the past 50 years. The average annual temperature in the region rose by 0.3-0.4 degree Celsius every 10 years from 1960 to 2012, about twice the average of the rest of the world. The temperatures rose more sharply during the winter compared to historical averages, as well as in the northern part of the plateau.

Ice core records showed that temperatures in the region rose the most during the 20th century. According to climate change models, the next 100 years may see the plateau warming by up to 4 degrees Celsius.

Xu Baiqing, a researcher with the ITPR and an author of the report, said that high-altitude areas are more vulnerable to global warming, so it is worrying but not surprising that temperatures on the Tibetan Plateau rose faster than the global average. Worse yet, the rising temperatures across the plateau are accompanied by retreating glaciers, disappearing permafrost and increasing natural disasters.

According to the report, glaciers on the plateau have been decreasing in size since the 20th century due to rising temperatures, and at a faster rate since the 1990s. Glacier shrinkage in the plateau is the most prominent in the Himalayan Mountains and Southeast Tibet, whereas glaciers stay relatively stable, or are even growing, in the Karakoram and Western Kunlun region.

Due to glacial melting, both the number and area of the lakes on the Tibetan Plateau have increased notably. The number of lakes exceeding 1 square km climbed from 1,081 in the 1970s to 1,236 in 2010, and 80 percent of lakes in the region have been expanding.

ICIMODs website states that “mountain systems are particularly sensitive to climate change and that the Third Pole region is home to some of the people most vulnerable to these changes in the world. Changes in the river systems and their basins have directly impacted on the wellbeing of millions of people.”

Xu noted that against the backdrop of global warming, glacier loss is not unique to the Tibetan Plateau, but a common crisis that all plateaus are facing. Still, as ICIMOD has noted, as the rate of warming in the Third Pole region is significantly higher than the global average, and the rate is higher at higher altitudes, it suggests “a greater vulnerability of the cryosphere environment to climate change.”

Natural disasters

Just as alarming are the increasing number and occurrences of natural disasters on the Tibetan Plateau as a result of global warming and increased human activity. The report said that disasters including landslides, torrential floods and avalanches are all expected to increase in the coming years, while fires will be more difficult to prevent and extinguish.

Data provided by the report showed that about 1,500 mountain torrents were reported on the plateau from 1950 to 2010, when strong and fast-moving water rushed down the slopes. The worst was in 1998 when more than 50 counties in Tibet Autonomous Region were affected.

Meanwhile, the report warned that frozen lakes and barrier lakes on the plateau are also posing a threat as more than 20 have overflowed during the course of the 20th century, leading to severe flooding in the region.

The report also recorded the fact that as one of the major forests in the nation, the risk of fire in this region is also high due to strong winds and a decrease in the total amount of rain and snow. From 1988 to 2014, a total of 373 forest fires were reported, according to the study. In addition, the scale of snow storms and avalanches has markedly expanded over the past 40 years under the influence of climate change and human activities.

A pure land

According to the ITPR report, airborne pollutants on the plateau have increased by 200 percent since the 1950s. However, both black carbon—a climate changing agent that heats the atmosphere and warms Earth—and persistent organic pollutants remain at a relatively low level, which is close to or lower than in the Arctic or the Alps, it notes. Though the level of heavy metal recorded in ice and lake cores of the plateau is higher than or similar to the South and North Pole regions, it is much lower than that in most areas.

Zhang Xianzhou, a researcher with the Institute of Geographic Sciences and Natural Resources Research under CAS, told reporters that the report shows the ecological environment of the Tibetan Plateau has been well preserved despite the onset of global warming and an increase of human activities in the region.

Xie Pengyun, Deputy Director of the ITPR, claimed that the sound ecological status quo of the Tibetan Plateau is inextricably linked to the efforts of the central and regional governments.

Based on data from reports of Xinhua News Agency, in order to protect the fragile environment on the Tibetan Plateau, the regional government of Tibet banned the mining of gold dust in 2006 and the exploitation of iron sand in 2008 as mineral resource exploration in Tibet had caused severe environmental damage. Fifty-six renovation projects had been carried out by 2010, in areas with a total size of 77.11 square km. Forty mining companies in Tibet that failed to meet environmental standards have been closed since 2010. Moreover, by 2010, areas with registered mining rights covered only 749.62 square km, less than 0.1 percent of the autonomous regions total area thanks to tightened controls.

Xu of the ITPR also noted that Tibets energy consumption mainly relies on clean energy and it has a service-dominant industrial mix, which also means less pollution compared to densely populated areas.

Some experts said that despite a retreat of the permafrost and the partial desertification of the Tibetan Plateau, the ecosystem is improving overall with the vegetation coverage of the plateau increasing remarkably, the boundaries of frigid and sub-frigid zones moving westward and northward, and the temperate zone expanding.

On one hand, as the Tibetan Plateau becomes warmer and moister, it will also become more suitable for vegetation growth and human habitation and production, said Xu. The report also noted that the scope of arable land has been expanding since the mid-1970s on the plateau, which helps increase the income of farmers and herdsmen.

Nevertheless, the report called for more government efforts protecting the ecology of the plateau. It suggested that a model green zone be established in Changtang, a high altitude plateau in western and northern Tibet and also Chinas highest vulnerable environment, which will be a safe and clean habitat for wild animals such as Tibetan antelopes and yaks.