While the terms natural hazard Vs. natural disaster are often used interchangeably, they don’t mean exactly the same. If you are interested in learning more about disaster preparedness and gaining a deeper understanding of these events, this guide is for you.
Read ahead to find out the terms’ definitions and compare them with the help of examples.
Natural Hazards Definition
What are natural hazards? These are events that can have a negative effect on humans, animals, or the environment.
Such phenomena are divided into two categories:
- Geophysical
- Biological
There are 18 natural hazards according to the National Risk Index of FEMA:
- Avalanche
- Coastal flooding
- Cold wave
- Drought
- Earthquake
- Hail
- Heat wave
- Hurricane (tropical cyclone)
- Ice storm
- Landslide
- Lightning
- Riverine flooding
- Strong wind
- Tornado
- Tsunami
- Volcanic activity
- Wildfire
- Winter weather
Note that natural hazards can also cause secondary natural hazard events. For instance, volcanic activity can cause ash and lava spread. However, the National Risk Index only considers main natural hazard events and not their results or after-effects.
Some natural hazards can be triggered or influenced by human activity, such as land-use change, drainage, and construction while others have a higher risk of occurring nowadays due to climate change.
What Is a Multi-Hazard Approach?
Each of the natural hazard types mentioned above have distinct characteristics, such as:
- Spatial scales they influence
- Duration
- Frequency
- Return period
- Intensity
- Impact
These factors contribute to a single-hazard type of assessment, in which every hazard is isolated and studied as a separate event. However, there is an alternative multi-hazard approach that examines the possible interdependencies between natural hazards and their interactions.
This offers a more comprehensive perspective on the state of events, as oftentimes one natural hazard triggers or increases the probability of one or several others, as in:
- Wildfire can increase the probability of landslides
- Earthquakes can trigger volcanic eruptions
- Heat waves are likely to be followed by drought
Such studies help advance disaster resilience - read more about it below.
Natural Disasters Explained
A natural disaster, on the other hand, is a negative impact that follows a natural hazard that took place and harmed a community significantly.
Such events may cause loss of lives or property destruction. They also typically leave significant economic and environmental damage.
The severity of the damage inflicted by natural disasters usually depends on the specific society’s resilience level and present infrastructure.
Nowadays, it’s often challenging to draw the line between natural, man-made and man-accelerated disasters, as human activity plays a critical role in causing "natural disasters". Besides, the rapid growth of the global population and its concentration in hazardous areas escalates the frequency and severity of disasters.
Hence, developing countries suffer from such emergencies fairly often due to ineffective communication paired with the lack of budgetary allocation for disaster prevention and management.
Natural Hazard Vs. Disaster Examples
Now that you know the definitions of these two related terms, let’s take a look at the examples that illustrate their differences:
- An earthquake is the hazard that resulted in the Great 1906 San Francisco earthquake disaster.
- Volcanic activity is the hazard that caused the Mt. Pinatubo eruption disaster in the Philippines in 1991.
- A tsunami was the natural hazard that created the deadly 2004 Indian Ocean tsunami disaster.