Contraction of Wetlands and Drying Up of Lakes

Wetlands, often referred to as earth’s kidney, has played a vital role in sustaining ecosystems that serves millions of lives. They act as an enormous sponge slowly releasing water into rivers all round year.


The fresh water wetlands on the Tibetan Plateau are distributed in an area of around 1,33,000 sq.km. With their wealth of stored carbon, these wetlands provide a potential sink for theatmospheric carbon. It was also observed that the role of wetland as a carbon sink was closely related with the water table and the amount of precipitation.

Grassland Degradation and Removal of Tibetan Pastoralists (Drogpas)

Tibet’s rangeland with an average altitude of 4500 meters, covers approximately 70% of Tibet’s total area. The Alpine grassland at high altitude occupies over 60% of the total rangeland in Tibet. Pastoralism on the Tibetan Plateau is an adaptation to a cold environment at elevations above the limit of cultivation. Consequently, pastoral nomads of Tibet have maintained a unique pastoral culture for more than 8000 years. Tibet’s grasslands represent one of the last remaining agropastoral regions in the world. The pasturelands are made habitable through the co-existence of the Tibetan people and their yaks. According to recent archaeological fieldwork, the Tibetan Plateau has been used extensively by pastoral nomads, who developed deep understanding of grassland dynamics and veterinary knowledge for close to 9,000 years.

Degradation of Frozen Earth Layers and Release of Green House Gases on the Tibetan Plateau

The presence or absence of the permafrost layer necessitates major variations in the soil’s physical structure mainly its moisture and nutrient content. The permafrost covers approximately 1.3 to 1.6 million sq. km. These covers have thickness ranging from 1 to 130 m, depending on such local characteristics as slope and exposure, altitude, geological structure, soils, and soil water content.

The permafrost and ground ice in Tibet. Image copyright EDD (CTA)

The alpine permafrost on the Tibetan Plateau stores about 12,300 million tons of Carbon. Significant amount of methane gas are also trapped in the permafrost, preventing its release into the atmosphere. The alpine permafrost on the Plateau are characterized by warm permafrost and rich ground ice, as a result they are sensitive to climate change and are particularly vulnerable to rising temperature.

Impact on River Hydrology in Tibet and Sustenance of Lower Riparian Countries

Snow peaks and glaciers enable Tibet to be the source of major rivers that flow into Asia and meet its water demand. Rivers such as Machu (Yellow), Drichu (Yangtze), Zachu (Mekong), Gyalmo Nyulchu (Salween), Yarlung Tsangpo (Brahmaputra), Macha Khabab (Karnali), Langchen Khabab (Sutlej), Sengey Khabab (Indus), Bhumchu (Arun) and Lhodrak Sharchu (Manas) have their sources in the Tibetan Plateau.

Drainage Basin of major rivers originating from the Tibetan Plateau (Image copyright: Environment and Development Desk, CTA)

Glacial Meltdown and Glacial Lake Outburst Floods

The scale of glacial melting on the west Rongbuk Glacier between 1921 and 2008. (Courtesy: RGS & David Breashears/GlacialWorks)

     

The Tibetan Plateau holds the Hindu-Kush Himalayan Ice Sheet, considered the largest ice mass outside the two poles. Hence scientists and geologists are increasingly using the name ‘Third Pole’ to pronounce the global significance of Tibet’s environment.

Tibetan Plateau and Climate Change: An Overview

            Source: EDD

Today, climate change and its impact is a grave concern to the entire world and one that can no longer be ignored. Such a change is not an inexorable force of nature but in fact, has known human causes and available solutions to restore climatic stability.

After Arctic and Antarctic, the Tibetan Plateau is Earth’s largest store of ice and a hotspot of climate change. Due to its unique geographical location and high altitude, Tibetan Plateau faces rapid changes in its weather patterns and ecosystems in more extreme ways than other parts of the world. The Plateau has been warming three times as fast as the global average and its glaciers are shrinking more rapidly than anywhere else.

Despite its cold environment, for thousands of years the Tibetan people inhabited this plateau and created cultural landscapes based on the principles of simplicity and non-violence, in harmonywith the environment.

Tibet and Climate Change: What’s the underlying story?

Why Tibet matters? Several scientists have realized the importance and Tibet’s role in the planetary climate. However, the six million Tibetans are silenced and forbidden to form their own organizations, people think Tibet is small and unimportant on a global scale. Actually, it is an immense upland, with an area of ~2.5 million sq. km and averaging over 4500 meters in elevation. It is not just the largest and highest area in the world today (also referred to as ‘the roof of the world’); it may be the largest and highest in all geologic history. It is also close to 2% of the land surface of the planet.