Humanitarian crisis overseas - natural hazard event

Impact 5
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upper likelihood error bar
risk indicator
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Impact & Likelihood
Impact key
5 Catastrophic
4 Significant
3 Moderate
2 Limited
1 Minor
Likelihood key
5 >25%
4 5-25%
3 1-5%
2 0.2-1%
1 <0.2%


A natural hazard event such as an earthquake, hurricane or tsunami may result in a humanitarian crisis overseas that directly impacts UK interests or citizens. For example, the UK has provided extensive humanitarian support to Turkey and Syria following devastating earthquakes in February 2023. This includes millions of pounds of financial support, medical personnel, and items such as tents and blankets.


The reasonable worst-case scenario is based on a major earthquake (magnitude 8.0+) occurring along the Sunda-Andaman fault zone in the Bay of Bengal. This would result in a tsunami that impacts Myanmar, Bangladesh, western India, and Sri Lanka, and cause casualties and fatalities among British and non-British nationals. The UK would also have a significant diaspora population from the affected regions.

This scenario could lead to the destruction of housing along the Bangladesh coast, impacting a significant number of people including refugees. In Dhaka, Chittagong and Kolkata, there would be destruction to critical infrastructure, with casualties, and displacement also expected. In Western Myanmar, a tsunami would impact the conflict-affected Ayeyarwady and Rakhine states. In Northeast India, populations would be impacted by destruction to property and infrastructure. In Sri Lanka, the north-eastern coast would be hardest hit.


This scenario could manifest across different geographies and be caused by different natural hazards. An event impacting multiple countries would require the same capabilities.

Response capability requirements

The UK’s capability to respond would be through the provision of international search and rescue, operational infrastructure support and humanitarian assistance. There may be an additional refugee dynamic, particularly for people with family based in the UK.


Recovery from the disaster would require sustained financial support from donors and the UN system. Society and conflict dynamics in conflict-affected states would likely be altered geopolitically.