What are the findings of the 2024 Hindu Kush Himalayas snow update?

Sub: Economy

Sec: Monetary Policy

Record Low Snow Persistence in the Ganga River Basin:

The Ganga River basin recorded its lowest snow persistence, with similar declines in the Brahmaputra and Indus basins, threatening the water supply to millions. This as a symptom of accelerating climate change.
Importance of Snow Persistence:

Snow persistence measures how long snow remains on the ground, crucial for the water supply in the Hindu Kush Himalaya (HKH) region.
Snowmelt contributes 23% of annual runoff to the region’s 12 major river basins, providing water to a quarter of the world’s population.
Impact on Water Supply:
- Ganga Basin: Snowmelt accounts for 10.3% of its water.
- In the Brahmaputra and the Indus basins as well, snowmelt brings 13.2% and around 40% of the water, respectively, versus 1.8% and 5% from glaciers.

2024 Report Findings:

Ganga Basin: Snow persistence was 17% below the long-term average, the lowest in 22 years.
Brahmaputra Basin: Snow persistence was 14.6% below normal.
Indus Basin: Snow persistence fell 23.3% below normal, though lower altitude areas had excesses.
Other Basins: Amu Darya (28.2% below normal) and Helmand (32% below normal) also saw record lows.

Causes of Lower Snow Persistence

Reduced and delayed winter precipitation due to high sea-surface temperatures and disrupted weather patterns.
Global warming and intensified La Niña–El Niño conditions destabilize snow accumulation.
Higher Snow Persistence in Other Regions:
Yellow River Basin: Snow persistence exceeded normal by 20.2%, due to the East Asian winter monsoon bringing cold, dry air from Siberia and Mongolia.

Long-term Solutions:

Reforestation: Planting native trees to help retain snow.
Weather Forecasting: Improved forecasting and early warning systems.
Water Infrastructure: Enhancing infrastructure and protecting snow-receiving areas.
Emission Reduction: Reducing greenhouse gas emissions to mitigate rising temperatures.

Hindukush-Himalaya Region:

Stretching over 3500 kilometres and across eight countries – Afghanistan, Bangladesh, Bhutan, China, India, Nepal, Myanmar and Pakistan – the Hindu Kush Himalaya is arguably the world’s most important ‘water tower’, being the source of ten of Asia’s largest rivers as well as the largest volume of ice and snow outside of the Arctic and Antarctica.
Together these rivers support the drinking water, irrigation, energy, industry and sanitation needs of 1.3 billion people living in the mountains and downstream.

Biodiversity of HKH region:

The mountain ecosystems of the Hindu Kush Himalaya (HKH) are diverse with one of the highest diversity of flora and fauna providing varied ecosystem services to one fourth of humanity. With four out of 36 global biodiversity hotspots the HKH is a cradle for 35,000+ species of plants and 200+ species of animals.
At least 353 new species—242 plants, 16 amphibians, 16 reptiles, 14 fish, two birds, and two mammals, and at least 61 invertebrates—have been discovered in the Eastern Himalayas between 1998 and 2008, equating to an average of 35 new species finds every year.
The Hindu Kush Himalaya (HKH) region is of global importance due to its unique biodiversity and is home to 4 of 34 global biodiversity hotspots, 6 UNESCO natural World Heritage sites, 30 Ramsar sites, 330 Important Bird Areas (IBAs) and 53 Important Plant Areas (IPAs).
In total, there are 60 ecoregion types (6 per cent of the world total), of which 30 are critical ecoregions.
HKH countries have established roughly 488 protected areas in the region with varying degrees of protection and status, covering 39 per cent of HKH terrestrial land.

Source: TH