Q2A · Explain in detail with respect to its causes and stages of Disaster management the ca…

Answer

1. Event and setting: On 26 December 2004 a major undersea earthquake near Sumatra generated a destructive Indian Ocean tsunami.
2. Causes and vulnerability: Seafloor displacement generated waves; exposed coastal settlements and limited warning readiness increased losses.
3. Impacts: Coastal inundation, housing and livelihood destruction and disruption across several countries, including India.
4. Response and recovery: Rescue, shelter and livelihood rehabilitation; India subsequently strengthened tsunami monitoring and warning through INCOIS/ITEWC.
5. Lessons: Combine ocean/seismic monitoring with last-mile warnings, marked evacuation routes, drills, risk-informed coastal development and accessible safe destinations.

For tsunami management, GIS provides a common location-based picture for agencies. Data quality, access, update time and field verification determine its usefulness.

Swipe across the diagram to read its labels ↔

Diagram: GIS combines location-based layers for decisions. Labels: GIS combines location-based layers for decisions | GIS combines location-based layers for decisions | Hazard layer | Flood extent / slope / drought | Exposure layer | People, homes, roads, hospitals | Resources layer | Shelters, teams, water supply | Decision supported | Which places face danger? Who needs | assistance? Which route is usable? Where | should resources go? | Check data dates, accuracy and field reports; a map is decision support.

1. Mitigation. Combine coastal elevation, modelled inundation and exposed settlements to guide land use and locate critical facilities outside high-risk areas.
2. Preparedness. Map safe high ground, marked routes, travel time, shelters and people needing assistance. Use realistic scenarios in evacuation drills.
3. Response. Overlay verified inundation, blocked roads, stranded people and available rescue resources. Use updated information to select safer access and prioritise urgent assistance.
4. Recovery. Compare before/after imagery, map damage and service restoration, plan safer reconstruction and monitor whether assistance reaches affected settlements.

Remote sensing can update affected-area mapping, but weather, resolution, signal availability and processing time may limit observations. Protect sensitive household and health information when sharing maps.

Four measures to reduce future losses

1. Monitoring and warning. Connect seismic/ocean observations to actionable public alerts.
2. Evacuation routes and drills. Mark safe routes and destinations and include people needing assistance.
3. Risk-informed siting. Keep critical facilities and new vulnerable development outside mapped inundation zones.
4. Resilient services and recovery. Protect lifelines, prepare backups and rebuild with reduced exposure and better construction.

These measures reduce disaster impacts; they cannot prevent the submarine earthquake or every tsunami.