Basics – Context of the News
- Event: Uttarakhand, Himachal Pradesh, and other Himalayan states have witnessed extreme rainfall, landslides, and flash floods in recent weeks.
- Impact:
- At least 15 deaths in the last few days.
- Multiple landslides, blocked roads, swollen rivers, and destruction of property.
- Pattern:
- Monsoon activity intensified in northwestern India.
- Region received 34% surplus rainfall in August 2025.
- Some districts received rainfall equivalent to an entire year’s quota in just 24–48 hours.
Relevance:
- GS-I (Geography):
- Monsoon variability, orographic rainfall, Himalayan topography.
- Disaster-prone areas (cloudbursts, landslides, flash floods).
- GS-III (Environment, Disaster Management):
- Climate change impacts, glacial melt, NDMA role.
- Vulnerability mapping and risk reduction strategies.
Why do hilly regions receive more rainfall?
- Topography effect:
- Hills force moisture-laden winds to rise, cooling them and causing rainfall (orographic effect).
- Sequential rain-bearing systems:
- Low-pressure systems from the Bay of Bengal travel northwards, increasing rainfall in the Himalayas.
- Seasonal behaviour:
- Northwest India often gets late-season (August–September) monsoon surges.
Data Highlights (Rainfall Departures)
- All-India Rainfall Departure (Aug 14–Sep 10): consistently above normal.
- Northwest India Rainfall:
- Aug 21–27: +132%
- Aug 28–Sep 3: +182%
- Sep 4–10: +57%
- Cumulative Rainfall (till Sep 15, mm):
- Uttarakhand: 1192 mm (+134%)
- Himachal Pradesh: 702 mm (+22%)
- J&K: 611 mm (+57%)
- Ladakh: 280 mm (+33%)
- Punjab/Haryana/Rajasthan: above/below normal but not as extreme as hill states.
Why are hilly regions more vulnerable?
- Steep slopes + fragile geology → high risk of landslides.
- Rivers/streams descend rapidly → cause flash floods.
- Narrow valleys funnel water and debris → more damage.
- Infrastructure exposure: roads, bridges, houses often located close to rivers and slopes.
- Examples: Udhampur (J&K) 630 mm rain in 24 hours; Leh–Ladakh 59 mm in 48 hours (highest since records began).
Role of Climate Change
- Warming atmosphere → holds more moisture, increases intensity of downpours.
- Changing monsoon patterns → longer dry spells + short bursts of extreme rainfall.
- Rising global temperatures → accelerates melting of Himalayan glaciers and snow, adding to flash floods.
- Extreme weather events becoming more frequent:
- Sudden cloudbursts.
- Intensification of western disturbances.
- Increased variability in rainfall distribution.
Disaster Linkages
- Not all heavy rains = disasters, but in Himalayas:
- Weak slopes + construction + deforestation magnify risks.
- Cloudbursts + extreme rainfall → landslides + flash floods.
- Example: Mandi, Kullu, Dharali, Tharali saw severe damage to homes, bridges, and crops.
- Human factor: Unregulated construction, road widening, and riverbank encroachments worsen vulnerability.
Overview
- Polity/Governance: State disaster preparedness, early warning systems, NDMA policies.
- Economy: Damage to roads, hydropower projects, tourism industry, agriculture.
- Society: Loss of lives, displacement, trauma in vulnerable hill communities.
- Environment: Deforestation, slope destabilisation, glacial retreat exacerbate risks.
- Technology: Need for better forecasting, Doppler radars, satellite monitoring.
Way Forward
- Strengthen early warning systems + last-mile connectivity in Himalayan states.
- Enforce scientific land use planning (ban construction in eco-sensitive zones).
- Promote climate-resilient infrastructure: slope stabilisation, drainage systems, safe housing.
- Invest in watershed management (afforestation, river restoration).
- Integrate climate change adaptation into state disaster management plans.
- Regional cooperation for Himalayan ecosystem sustainability (since many rivers are transboundary).
