UPSC DAW Mains Answer Writing 2025 20th August

UPSC DAW Mains Answer Writing 2025 20th August

Question

Discuss the geophysical processes leading to the occurrence of cloudbursts in India. Highlight their impacts with suitable examples. Suggest measures for effective early warning and mitigation in cloudburst-prone regions. (15 marks, 250 words) 

Model Answer

Introduction:  

  • According to the India Meteorological Department (IMD), a cloudburst is defined as rainfall of more than or equal to 100 mm per hour over an area of around 20-30 sq. km. Though common in the Himalayas, they also occur in the Western Ghats, Northeast India, and urban centres. The IPCC AR6 notes a rising trend of extreme precipitation events in South Asia, intensified by global warming. 

 Geophysical Processes Leading to Cloudbursts: 

  • Orographic Lifting: Moist monsoon winds forced up steep Himalayan slopes → rapid cooling & condensation. 

  • Interaction of Monsoon & Western Disturbances: Convergence of moist and cold winds promotes cumulonimbus formation. 

  • Convective Instability: Intense surface heating → violent vertical air currents → localized downpours. 

  • Topographic Channelling: Narrow valleys trap moisture, intensifying rainfall. 

  • Climate Change Link: As per IPCC AR6, a warmer atmosphere holds around 7% more moisture per 1°C rise, amplifying heavy rainfall. 

 Impacts of Cloudbursts: 

  • Human & Social Impacts 

  • Cloudburst cause displacement, trauma, and disproportionate effect on vulnerable groups, along with large number of casualties. 

  • E.g. Uttarakhand 2013 disaster killed more than 5000 people. 

  • Environmental Impacts 

  • Cloudbursts trigger landslides and debris flows, as evident from Leh 2010 cloudburst which caused more than 200 deaths & destroyed villages. 

  • It also causes river course changes (E.g. Mandakini River shifted during 2013 Kedarnath disaster) and siltation of reservoirs and biodiversity loss. 

  • Economic Impacts 

  • Along with Infrastructure damage, there is hydropower disruption, crop/orchard losses, and hit to tourism/pilgrimage due to cloud bursts. 

  • Urban & Health Impacts 

  • Waterlogging leads to disease outbreaks where there can be post-flood leptospirosis and diarrhoeal risks. 

  • Also, cloudbursts can paralyse urban areas, as seen during the Mumbai 2005 floods, which recorded 944 mm in 24 hrs. 

  • Governance & Security Dimensions 

  • Border infrastructure (BRO roads in Ladakh, Arunachal) are often washed away due to cloudbursts, affecting security logistics. 

 Measures for Early Warning & Mitigation:  

  • Early Warning Systems: 

  • IMD Doppler Weather Radars (DWRs): Expansion of radar network across Himalayas. 

  • Increase weather monitoring satellites: Provide real-time monitoring of convective clouds. 

  • Risk Mapping & Land-use Planning: 

  • Zonation maps to regulate construction in fragile ecosystems, as suggested by NITI Aayog. 

  • Detailed hazard zonation maps for Himalayan states using historical rainfall and satellite data. 

  • Community-Based Preparedness: 

  • Creating local disaster response forces equipped for flash flood rescue. 

  • Infrastructure & Ecosystem Resilience: 

  • Creating climate-resilient construction codes for hill regions and ensure restoration of catchment areas and afforestation to reduce runoff. 

  • International Best Practices: 

  • Japan’s ‘Nowcasting Rainfall’ system (5-min interval satellite-radar integration) could be adapted for India. 

Conclusion:  

  • Cloudbursts, though highly localized, have disproportionately large socio-economic impacts. Building resilience requires a multi-layered strategy and as emphasized in the Sendai Framework for Disaster Risk Reduction (2015–2030), reducing disaster risk requires mainstreaming risk-sensitive development, which is an imperative India cannot postpone.