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Hazards

About

Hazards are environmental calamities that bring harm to people, buildings, and society as a whole. They can be Natural, or Manmade in nature.

  1. Earthquake
  2. Flood
  3. Heat-Wave

At times, hazards can cause secondary natural hazard events that cause additional hazards, leading to a Multi-Hazard situation. These hazards can also interact with each other, causing more complex environmental phenomena.

For example, Volcanic Activity can create secondary hazards such as Air Pollution, Lava Spread, etc. Similarly, Flooding due to inefficient drainage infrastructure can cause water-lodging, facilitating insect breeding, and spread of diseases.

Natural-Hazards

18 Hazards such as Heat-Wave, Hurricane, Riverine-Flooring, Wildfire, Tsunami, Earthquake, etc. are are classified as natural hazards1. In the USA, these are included in National Risk Index.

Manmade-Hazards

If the cause of a hazard is man-made, such as flooding due to dam failure, or inefficient drainage, etc. are classified as manmade hazards1 and are generally excluded from the National Risk Index.

Multi-Hazard

Multi-hazard refers to situations / scenarios where more than one hazard is witnessed simultaneously.2

The effect of a multi-hazard is usually larger than the sum of it's individual hazards, due to interactions between the various hazards.

Extreme-Multi-Hazard

When the magnitude of the hazard is extremely high (from a statistical perspective / based on historical data), a multi-hazard is classified as extreme.

Compound Multi-Hazard

When in a multi-hazard scenario, multiple or successive extremes are identified, or the effects of hazards are amplified by starting / background conditions, or both, they are classified as compound.

See Also

  1. National Risk Index
  2. Understanding Compound, Interconnected, Interacting, and Cascading Risks: A Holistic Framework, by David Alexander on onlinelibrary.wiley.com (15 June 2018)
  3. A review of quantification methodologies for multi-hazard interrelationships, by Alois Tolloy, Bruce D. Malamud, Hugo Winter, Amelie Joly-Laugel on sciencedirect.com (September 2019)

References

  1. Natural Hazards, on fema.gov (6 February 2024) ↩↩

  2. Multi Hazard Risk Analysis Methodologies, on anticipation-hub.org (15 November 2021) ↩