GS Paper 1
Syllabus: Indian Geography
Source: BBC
Context: A new study has found that mountains across the globe, including the Himalayas, are now seeing more rainfall at elevations where it has mostly snowed in the past.
Status of Rainfall and Snowfall in the Himalayan Region:
- IPCC Special Report on the Ocean and Cryosphere in a Changing Climate (2019): The IPCC reported that snowfall had decreased in mountain regions, including the Himalayas, due to higher temperatures, particularly at lower elevations.
- Changing Precipitation Patterns: Scientific studies have indicated shifts in precipitation patterns in the Himalayan region, with more instances of extreme precipitation occurring as rainfall rather than snowfall, even at higher altitudes.
Why Himalayan region is having Increased rain and reduced snowfall?
- Changing Weather Patterns: Alterations in atmospheric circulation, jet streams, and other weather systems can result in shifts in precipitation patterns.
- Global Warming and Temperature Rise: As global temperatures increase, the atmosphere can hold more moisture, leading to increased evaporation and subsequent precipitation.
- Elevated Freezing Levels: The freezing level, also known as the zero-degree isotherm, is the altitude at which falling precipitation transitions from snow to rain.
- Rising temperatures associated with global warming have caused the freezing level to rise, leading to more rain at higher altitudes that used to receive snowfall.
- Snowfall Reduction: Warmer temperatures cause more precipitation to fall as rain rather than snow
- Feedback Loops: Less snow cover means there is less reflective surface to bounce sunlight back into space (albedo effect), causing further warming and contributing to the shift from snow to rain.
- Warming-Induced Atmospheric Changes: This can lead to a greater intensity of storms, causing heavy rainfall events in areas where snowfall was historically dominant.
Impact of increased rain and reduced snowfall in the Himalayan region:
| Impact | Description | Examples |
| Increasing disasters | Shifts from snowfall to rainfall at higher elevations, affect water availability and hazards. | More instances of heavy rainfall cause flash floods. |
| Water Resource Changes | Altered snowmelt and rain patterns affect river flow, water availability, and ecosystem dynamics. | Changes in river flow and hydrological patterns. |
| Increased Flood and Landslide Risk | Rainwater saturates the soil, leading to landslides, debris flows, and flash floods. | Uttarakhand’s 2013 flash floods due to excessive rainfall. |
| Impact on Ecosystems and Biodiversity | Altered precipitation affects vegetation, wildlife, and fragile mountain ecosystems. | Changes in alpine flora and fauna due to shifting climate. |
| Socioeconomic Consequences | Reduced snowfall impacts winter tourism, agriculture, and water-dependent livelihoods. | Ski resorts face challenges due to shorter snow seasons. |
| Glacial Lake Outburst Floods (GLOFs) | Faster glacial melt leads to unstable glacial lakes and potential GLOFs, posing flood risks downstream. | Imja Lake in Nepal is at risk of GLOF due to glacial melt. |
| Infrastructure Vulnerability | Changes in rainfall patterns challenge infrastructure resilience and lead to increased disaster risks. | Damage to roads, bridges, and hydropower plants. |
Insta Links:
Sansad TV: Perspective- Monsoon: Changing Patterns
Mains Links:
Discuss how climate change will affect the rainfall pattern in India. Also, analyze the risks that it poses to food security in India
