8. Physical Geography of British Columbia
The term natural hazards refers to any natural process that poses a potential threat to human life and property. Natural hazards tend to be repetitive events and are predictable. Some of the most devastating natural hazards include:
- Volcanic eruptions
- Heat waves
Earthquakes are perhaps the most dangerous of all natural hazards. During the 20th century more than a million lives were lost worldwide due to earthquakes. Each year more than 50 earthquakes occur that are strong enough to be felt in Canada. As discussed in the section on geology, BC is subject to frequent and violent earthquake activity because of the presence of an active boundary between tectonic plates.
Periodic disturbances from hazards such as earthquakes, volcanic eruptions and flooding adversely affect:
- Fertile soil
- Available water
- Diverse land and life
- Aesthetic beauty
Fortunately, some hazards can be predicted and much can be learned from past events. With appropriate data collection and analysis, scientists can use statistical models to identify patterns and evaluate the frequency of a particular event. For example, certain soil conditions may lead to the likelihood of landslides. Learning more about natural hazards and communicating this knowledge to the public can encourage hazard mitigation measures that may reduce the damage that could potentially be incurred by disaster. The predictability of hazards allows events to be forecasted and officials to implement warning systems, such as the tsunami warning system that is in place along the Pacific coast.
Natural hazards and their effects are closely linked to our environment, and one hazardous event can set off another. For example, an area with weak soils may be at risk of a landslide. A volcanic eruption can cause a landslide, and a subduction earthquake may cause a tsunami. Hazards often influence or disrupt ecosystems: for example, human-caused landslides in the past have cut off Hell’s Gate in the Fraser River leading to massive declines of the Fraser River sockeye population and impacts across the ecosystem.
Risk from hazards can be estimated and adverse effects of hazards can be minimized through efforts such as Emergency Management BC. Communities that have a more active versus reactive response to hazards stand a better chances of being prepared when adverse events occur. Emergency preparedness teams and communities need to consider land use planning, hazard-resistant construction and the protection of ecosystems.