tibetpolicy.net-Tenzin Youdon
Introduction
With the acceleration of urbanization and the Chinese government policy in reducing the cost of mineral transportation and other factors, the construction of the Tso-ngon -Lhasa Railway in the Tibet plateau has started at the beginning of 2007. This railroad provides a major access route into Tibet from Siling to Lhasa which extends to 1118 km. The construction began in 2001 and was completed in 2006 despite the challenges faced by the engineers in building the railroad across an unstable landscape. The Tso-ngon-Lhasa Railway is said to be the highest elevated and the longest railway across a permafrost region in the world.
In the early 1950s, due to unstable roads and poor transportation, traveling within and out of Tibet would take nearly from six months to a year. According to Evelyne Yohe and Laurie J. Schmidt, sometimes China was forced to use camels to transport cargo to Tibet. It is said that 12 camels on average, died for every kilometer the caravan traveled across the Tibetan Plateau and over high mountain passes.
According to Tingjun Zhang, a scientist at the National Snow and Ice Data Center in Boulder, Colorado, “The Tso-ngon Lhasa railroad is the most ambitious construction project in a permafrost region since the Trans-Alaska Pipeline.” He studies the effects of climate change on permafrost areas all around the world.
However, building a railroad across the highest plateau in the world is hugely risky. Due to the thin air on the high plateau, non-acclimatized workers risk of nosebleeds, blackouts, and even death. Due to this, they need to carry oxygen bags, undergo daily medical monitoring, and work no more than six hours a day. To avoid prolonged exposure to the extreme climate conditions, workers rotate off the plateau every few weeks. In addition to the risks associated with construction at high altitudes, the biggest challenge of building a railroad faced by the engineers across an unstable landscape was the permafrost. The total length of the railway in permafrost regions is approximately 550km and approximately 82km passes through discontinuous permafrost. Permafrost along the railroad lies in the eastern regions of the plateau.
Permafrost is defined as the ground with a mixture of soil, gravel, and sediment bound together by ice that remains at or below 0°C for at least two or more consecutive years. As one of the main components of the cryosphere, permafrost secures highly compressed carbon and methane gases created from decomposed organic remains which are the leftover materials from dead plants that couldn’t be decomposed due to the extreme cold weather. Permafrost in the Tibet plateau covers 1.06 x106 km2 or approximately 40% of the area of the plateau. This permafrost is highly sensitive to climate change and surface disturbances, especially to air temperature changes and is also considered the indicator region for climate and environmental changes. Outside of the Arctic and Boreal biomes, the Tibet plateau contains the largest permafrost region and is the source of the most major Asian rivers such as the Yangtze, Yellow, Indus, and Mekong. The Tibet plateau serves as the Water Tower for nearly 1.4 billion people (Yao et al., 2019). The Tibet plateau also plays a vital role in the stability of Asia’s climate system, water supply, biodiversity, and regional carbon balance making it crucial for the global biosphere integrity and sustainability of the surrounding areas. Click here to read more.