Gangotri Glacier System's hydrological changes linked to warming, increased rainfall-runoff
The study on the Gangotri Glacier System (GGS) further details that while mean annual temperature increased, snowmelt declined due to reduced snow cover, and rainfall-runoff and base flow increased over 1980–2020. The GGS comprises several glaciers, including the largest, Gangotri (140 km²), covering 549 square km. It receives precipitation from western disturbances in winter and the Indian summer monsoon. The findings imply warming-induced hydrological changes, with increased rainfall-runoff and base flow trends. This year's intense summer monsoon in North India, with significantly more rain, has led to frequent floods, often mislabeled as 'cloudbursts,' which are defined as over 10 cm of rainfall in an hour over an area less than 30 square km.
Key Points
- Despite warming, GGS experienced declining snowmelt but increasing rainfall-runoff and base flow from 1980-2020.
- The GGS includes glaciers like Meru, Raktavaran, Chaturangi, and the largest, Gangotri (140 km²).
- The GGS receives precipitation from both winter western disturbances and the Indian summer monsoon.
- Increased rainfall-runoff trends suggest warming-induced hydrological changes, contributing to intense floods in North India.
- A 'cloudburst' is specifically defined as over 10 cm of rainfall in an hour over an area less than 30 square km.
Exam Facts
- Gangotri Glacier (140 km²) is the largest glacier in the GGS.
- GGS covers an area of 549 square km.
- Average seasonal rainfall (May to October) is around 260 mm.
- Definition of a 'cloudburst': over 10 cm of rainfall in an hour over an area less than 30 square km.
Read it. Retain it. Recall it.
Get spaced-repetition flashcards, daily quizzes and offline access — free on Android.