From UPSC perspective, the following things are important :
Prelims level : GLOF
Mains level : Climate change impact
A massive glacier burst at Chamoli in Uttarakhand yet again bringing back our focus to the dangers of climate change.
A wake-up call!
Uttarakhand is often at the heart of various Himalayan disasters such as flash floods, cloud bursts, avalanches and earthquakes.
The Chamoli incident signifies the dawn of ugly faces of climate disaster for which the mankind is clueless. At last, someone has to be blamed, isn’t it?
What is the news?
- Experts are uncertain about what caused the massive glacier burst at Chamoli in Uttarakhand.
- It is unclear whether there was an avalanche in the area recently or whether the lake breach was the result of construction, anthropological activities, climate change etc.
What is GLOF?
- A GLOF is a type of outburst flood that occurs when the dam containing a glacial lake fails.
- An event similar to a GLOF, where a body of water contained by a glacier melts or overflows the glacier, is called a jökulhlaup.
- The dam can consist of glacier ice or a terminal moraine.
- Failure can happen due to various factors such as:
- Erosion, a buildup of water pressure
- Avalanche of rock or heavy snow
- Earthquake or volcanic eruptions under the ice or
- Displacement of water in a glacial lake when a large portion of an adjacent glacier collapses into it
Possible causes for Chamoli
- An avalanche is falling masses of snow and ice which gathers pace as it comes down the slope.
- But an avalanche is unlikely to result in the rise of water of that magnitude what Chamoli witnessed.
- What happened in Uttarakhand in 2013 was a multi-day cloudburst.
- It is a sudden, very heavy rainfall accompanies by a thunderstorm. But it generally happens in monsoon.
- In fact, the season in which such a disaster was witnessed has surprised experts as there is no immediate trigger that can be pointed to as the reason why water level rose to that level washing away two hydro projects.
Why always Uttarakhand?
- Human activities profoundly affect the earth’s climate and mountains are a sensitive indicator of that effect.
- The mountain ecosystem is easily disrupted by variations in climate owing to their altitude, slope and orientation to the sun.
- As the earth heats up, mountains glaciers melt at unprecedented rates.
- Several scientists believe that the change occurring in the mountain ecosystems may provide an early glimpse of what could come to pass in a lowland environment.
- The current policy of the government of pursuing hydro-power projects indiscriminately cannot be ignored.
- The entire State of Uttarakhand is categorised as falling in Zone-IV and V of the earthquake risk map of India.
- The potential of the cumulative effect of multiple such projects has turned out to be more environmentally damaging than sustainable.