Why in the news?

  • A new study by IIT Indore, ICIMOD (Nepal), and U.S. researchers has found that the Gangotri Glacier system has lost about 10% of its snowmelt flow in the last four decades (1980–2020).

Gangotri Glacier

  • Location:
    • Situated in Uttarakhand, within Gangotri National Park.
    • Lies in the Greater Himalayan ranges (Central Himalaya).
  • Features:
    • Fed by snowmelt, glacier melt, rainfall, and base flow.
    • Contributes ~25% of Ganga’s water in non-monsoon months.
  • Fact:
    • Largest glacier in the Garhwal Himalayas; source of the Bhagirathi River, the headstream of the Ganga.
    • Considered sacred in Hinduism, with its snout at Gaumukh cave revered as the origin of the Ganga.
  • Climate Change:
    • Decline in snowmelt contribution: from 73% (1980–90) → 63% (2010–20).
    • Temperature rise: +0.5°C (2001–20 vs. 1980–2000).
    • Peak flow shift: from August → July due to earlier melting.
    • Snout retreat: steady shrinkage; aligns with Himalayan trend of ~46 cm annual ice thickness loss.
  • Strategic Importance:
    • Water Security: Lifeline for millions in the Ganga basin.
    • Hydropower: Seasonal discharge changes affect generation capacity.
    • Agriculture: Altered flow timing may cause irrigation stress.
    • Cultural Significance: Sacred origin of Ganga, central to Hindu faith & pilgrimages (Char Dham Yatra).