Increasing frequency of landslides in the Sedongpu Gully of the Tibetan Plateau

Source: The post increasing frequency of landslides in the Sedongpu Gully of the Tibetan Plateau has been created, based on the article “Frequent mass wasting in Tibet a cause for worry in India” published in “The Hindu” on 26th August 2024

UPSC Syllabus Topic: GS Paper 1- geography- changes in critical geographical features (including water-bodies and ice-caps)

Context: The article discusses the increasing frequency of landslides in the Sedongpu Gully of the Tibetan Plateau, linked to warming temperatures and earthquakes. These events could cause severe flooding and sediment issues in India’s northeast, particularly affecting the Brahmaputra River.

For detailed information on Making sense of Assam floods read Article 1, Article 2

What is Happening in the Sedongpu Gully?

1. The Sedongpu Gully is in the Tibetan Plateau, near the border with Arunachal Pradesh, India. It is 11 km long and drains into the Tsangpo River, which becomes the Siang River in India. The Tsangpo creates one of the world’s deepest gorges, called the Great Bend.
2. Since 2017, more than 700 million cubic meters of debris have been mobilized in the Sedongpu Gully. This area has seen a rapid increase in mass-wasting events, including landslides.
3. The main causes are warming temperatures and earthquakes, with 13 major events happening after 2017.
4. Before 2012, temperatures in the area rarely exceeded 0º C. From 1981 to 2018, annual temperatures increased by 0.34º to 0.36º C, higher than the global average. This warming is contributing to more landslides and instability in the region.

What are the potential impacts on India and Bangladesh?

1. The sediment from these landslides could cause significant problems downstream in India and Bangladesh.
2. The Brahmaputra River, one of the world’s most sediment-laden rivers, could carry even more sediment, leading to more severe flooding, riverbank erosion, and navigation issues.
3. The 2000 flash floods in Arunachal Pradesh and Assam, caused by a similar landslide in Tibet, are a worrying example.

Why is there concern over dams in the region?

1. China plans to build a massive 60-gigawatt hydropower project on the Tsangpo River.
2. This project could increase the risk of river choking and flash floods, especially in a geologically unstable area.
3. India’s planned dams on the Siang could also face similar risks, potentially affecting millions of people downstream.

What Should be Done?

1. Monitor Geophysical Events: Regularly observe landslides, rockfalls, and other erosional activities in the Sedongpu Gully and surrounding areas to anticipate future risks.
2. Focus on Sediment Management: Address the increasing sediment load in the Brahmaputra River, which carries more than 800 tonnes at Guwahati, to prevent severe flooding and erosion.
3. Evaluate Impact of Dams: Reassess plans for large dams like China’s 60-gigawatt project on the Tsangpo and India’s Siang projects, considering the region’s geophysical instability and past events like the 2000 Arunachal floods.

Question for practice:

Examine how the warming temperatures and earthquakes in the Sedongpu Gully region contribute to increased landslides and their potential impacts on downstream areas in India and Bangladesh.