Geohazard Risk Analysis

Introduction

Geohazard risk analysis is the process of assessing the potential danger and damage that can be caused by geohazards like earthquakes, volcanoes, landslides, floods, etc.
This process combines an understanding of the geohazard occurrence and behaviour with the vulnerability and exposure of elements at risk to calculate the potential impacts.

Risk Identification and Assessment

This starts by mapping the geohazard zones, which are areas likely to be affected by specific geohazards based on geological, topographical, and climatic factors.
The probability of occurrence of these hazards in these zones is then worked out from geological records, statistical analysis of previous events, and amount of human activity, infrastructure, etc.
For instance, seismic hazard maps can illustrate the likelihood of earthquake shaking at different locations, while flood hazard maps can depict areas prone to flooding.

Vulnerability and Exposure Analysis

The next step involves assessing the vulnerability and exposure of the elements at risk, such as lives, property, infrastructure, environment, etc.
Vulnerability refers to the degree of loss resulting from the occurrence of a geohazard, which can depend on factors such as building design, construction material, etc.
Exposure refers to the extent to which the elements at risk come into contact with the geohazard. It involves assessing the number of people, properties, etc., that may be exposed.

Risk Estimation

Geohazard risk estimation is the process of calculating the expected losses due to a specific geohazard by multiplying the probability of occurrence, vulnerability, and exposure.
These estimations are generally done for different geohazard intensity levels or return periods.

Risk Management and Mitigation

Geohazard risk management and mitigation are critical steps to reduce the potential risks associated with geohazards.
It involves planning and implementing strategies to avoid, reduce or transfer the risks. Examples include building design, strict zoning laws, insurance, etc.
Another integral part of this process is creating emergency preparedness plans and early warning systems, which plays a significant role in reducing the loss of life and property damage in the event of a geohazard.
Last but not least, improving public awareness and education regarding geohazards and adaptation measures safeguards communities against potential risks.