What is a natural hazard?
A natural hazard is an unexpected or uncontrollable natural event of unusual intensity that threatens people's lives or their activites. Atmospheric hazards are weather-related events, whereas geologic hazards happen on or within the Earth's surface. However, it is important to to understand that atmospheric hazards can trigger geologic hazards, and geologic hazards can trigger atmospheric hazards.

Why should we be concerned about natural hazards?
On average, about 150,000 people are killed worldwide by natural hazards each year. Unfortunately, the economic cost of natural hazards is increasing dramatically. In the 1990's, the average cost of all natural hazards in the United States doubled from $25 billion to $50 billion per year. Globally, losses from natural hazards are also increasing, mostly due to the rapid increase in human population. This unprecedented number of people has reduced resource availability and forced people to live in marginal areas where natural hazards occur more frequently.

Besides the direct impacts of natural hazards, such as a flood destroying a house, there are usually many indirect impacts, such as a flood spreading disease for weeks after the initial destruction. Although these indirect impacts may be less obvious initially, they are often more costly and can add years on to the recovery time from a disaster. Often, there is no such thing as a complete recovery - natural disasters can forever change our way of living.

Human activities can increase how often a natural hazard occurs and how severe a natural hazard can become. Understanding when, where, why, and how natural hazards occur is the first step in minimizing their impacts on our lives. This website works to that end.

Atmospheric hazards:

climate change | fog
hurricane | snow
temperature extreme
thunderstorm | tornado
wind | wildland fire

Geologic hazards:

drought | earthquake
flood | ice storm
slope failures | tsunami
volcano