Chinese researchers see climate change link to glacial collapse, warn of rising disaster risks
A study by researchers in China has linked climate change to glacial collapse on the Tibetan Plateau, warning of rising associated disaster risks.
The Tibetan Plateau's total glacier area has fallen to about 39,000 sq km, down from earlier estimates of roughly 44,000-51,000 sq km, indicating continued long-term glacier retreat.
More than 14,000 glacial lakes were observed across the plateau, together covering over 1,100 sq km, with lakes near China's southern borders expanding in area by about 1% annually.
Glaciers in the Gangdise, Nyenchen Tanglha, and Himalayan ranges were found to have shrunk by roughly 40% over the past six decades, raising concerns about flood risk for downstream countries including India and Nepal.
The Tibetan Plateau as the "Third Pole" and Asia's Water Tower
The Tibetan Plateau, sometimes called the "Third Pole" for holding the largest ice mass outside the polar regions, is the source region for several of Asia's major transboundary rivers, making its glacial health directly relevant to water security in South and Southeast Asia.
Key Details
- Rivers originating on or fed by the Tibetan Plateau/Himalayan glacier system include the Indus, Sutlej, Brahmaputra (Yarlung Tsangpo in Tibet), Ganga tributaries, Mekong, and Yangtze — collectively supporting well over a billion people downstream.
- The plateau spans roughly 2.5 million sq km at an average elevation above 4,500 m, straddling the China-India-Nepal-Bhutan-Pakistan periphery known as the Hindu Kush Himalaya (HKH) region.
- Glacier retreat here affects both immediate flood hazards (glacial lake outburst floods) and long-term dry-season river flows, since glacial melt buffers river discharge between monsoons.
Because the Tibetan Plateau feeds rivers flowing into India (Brahmaputra, Indus, Sutlej), a Chinese-side finding of accelerated glacier loss and glacial lake expansion has direct downstream implications for India's water availability and flood exposure.
India-China Transboundary River Data-Sharing Mechanisms
Since the Tibetan Plateau's rivers cross into India, India and China have historically maintained bilateral Memoranda of Understanding for hydrological data sharing during flood season, given the absence of a comprehensive water-sharing treaty between the two countries.
Key Details
- A 2002 MoU provided for China to share flood-season hydrological data on the Brahmaputra (Yarlung Tsangpo); renewed periodically (2008, 2013, 2018), it lapsed in June 2023 and remains under renewal discussion.
- A separate 2005 MoU covered the Sutlej (Langqen Zangbo in Tibet) for flood control and disaster mitigation data; it lapsed in 2020.
- Under these arrangements, China has supplied hydrological data twice daily during the flood season (1 June-15 October) for a nominal annual payment from India.
- No comprehensive water-sharing treaty exists between India and China, unlike India's treaties with Pakistan (Indus Waters Treaty, 1960) or Bangladesh (Ganga Waters Treaty, 1996).
Findings of accelerating Tibetan Plateau glacier and glacial lake changes strengthen the case for renewing and expanding these lapsed data-sharing MoUs, since India's flood early-warning capability on the Brahmaputra and Sutlej depends heavily on upstream Chinese data.
National Mission for Sustaining the Himalayan Ecosystem (NMSHE)
NMSHE is one of the eight missions under India's National Action Plan on Climate Change (NAPCC, 2008), dedicated specifically to monitoring and building resilience in the Indian Himalayan region against climate-driven glacial and ecosystem change.
The Chinese study's findings on rapidly multiplying glacial lakes parallel exactly the kind of hazard NMSHE is meant to track on the Indian side of the Himalaya, reinforcing calls for cross-border glacial lake monitoring given that lake formation and expansion do not respect national boundaries.
- Tibetan Plateau glacier area: fallen to about 39,000 sq km, from earlier estimates of ~44,000-51,000 sq km.
- Glacial lakes observed across the plateau: more than 14,000, covering over 1,100 sq km combined.
- Glacial lake area near China's southern border: expanding by about 1% annually.
- Glacier shrinkage in Gangdise, Nyenchen Tanglha, and Himalayan ranges: roughly 40% over six decades.
- India-China Brahmaputra hydrological data MoU: signed 2002, lapsed June 2023; Sutlej MoU: signed 2005, lapsed 2020.
- NMSHE: one of 8 missions under NAPCC (2008), covers 12 Himalayan states/UTs of India.
- 2023 South Lhonak GLOF (Sikkim): ~50 million cubic metres of water released, 1,200 MW Teesta III dam destroyed.