Cloudburst

A cloudburst is a natural phenomenon in which there is sudden and intense rainfall in an area. This intense rainfall can trigger other related hazards such as flash floods, urban flooding, Glacial lake Outburst Floods (GLOFs) etc. Hence, cloudbursts are very destructive when they occur over or near any densely populated areas. The cloudburst phenomenon can be seen in areas that contain hilly terrain. In India, they can occur in the Himalayan regions, the Western Ghats and the Northeastern states. Generally, they occur in the monsoon season. Due to climate change, the rainfall distribution and pattern are being disturbed. Some studies have linked the increased frequency of the cloudburst to climate change. Every year, there is an occurrence of a cloudburst and there is extensive damage to life and property. Hence, there is an urgent need to understand risks and take steps regarding disaster risk reduction and mitigation.

In August 2023, a cloudburst wreaked havoc in Himachal Pradesh. Very intense rainfall triggered flash floods and landslides in many areas, which resulted in loss of life and property damage. This was not an isolated incident. Every year, there is a similar disaster in the Himalayas and the Northeastern states. Although they develop over an area during the monsoon season, they are different from normal rainfall.

• According to the Indian Meteorological Department (IMD), in a cloudburst, there is very heavy rainfall, almost at a rate of 100 mm/hour in a localised area. The area of this heavy rainfall is generally very small, up to 20-30 km2 .
• They develop in the hilly areas. When the moisture carrying warm air rises vertically up on the steep hill, it pulls moisture from surrounding clouds to a very high altitude. This eventually cools down and forms large cumulonimbus clouds.
• The water droplets become larger and larger. Eventually, there comes a time when the warm air currents cannot hold this moisture, and there is a burst or heavy downpour.
• Many times cloudburst events are not noticed if they occur over uninhabited areas.
• In India, affected areas are the Himalayan states, the Western Ghats and the Northeastern states.

• Mapping: Deploying modern remote sensing technology to map risk-prone areas.
• Prediction Models: Compiling rainfall data and using advanced computing tools to predict patterns of rainfall.
• Mitigation: Deploying local expertise and technical expertise to mitigate landslides.
• Awareness: Timely dissemination of information or warnings to the last mile.
• Capacity building: of Urban local bodies (ULBs)/Panchayati Raj Institutions(PRIs) so that they can prepare for and tackle such events.
• Interagency coordination: among various levels of government.
• Promoting Research and development and monitoring tools to predict such adverse events.

• Widespread: All development sectors must imbibe the principles of disaster risk management.
• Comprehensive: Risk coverage must include all, starting from poor households to SMEs (Small and Medium Enterprise) to multinational corporations to nation states.
• Women’s leadership: and greater involvement should be central to disaster risk management.
• Invest in risk mapping globally to improve global understanding of nature and disaster risks.
• Leverage technology to enhance the efficiency of disaster risk management efforts.
• Develop a network of universities to work on disaster-related issues.
• Awareness Through Technology: Utilise the opportunities provided by social media and mobile technologies for disaster risk reduction.
• Build on local capacity and initiative to enhance disaster risk reduction.
• Research & Reflection: Make use of every opportunity to learn from disasters and, to achieve that, there must be studies on the lessons after every disaster.
• International Coordination: Bring about greater cohesion in international response to disasters.

According to the Intergovernmental Panel on Climate Change (IPCC) Sixth Assessment Report (AR6), climate change is causing extreme weather events all over the world, particularly in highly vulnerable areas such as India. Cloudbursts are one of such extreme weather events. These will ntensify over the years, even after climate change mitigation efforts are taken. Therefore, there is a need for risk assessment and adaptation. There should be a culture of awareness, preparedness, and alertness. The use of modern technology in monitoring should be promoted. Capacity building should be prioritised so that there is a collective response to disaster. In this regard, the Prime Minister’s 10-point agenda on Disaster Risk Reduction (DRR) should be followed, which presents a holistic approach to dealing with such disasters.