A natural disaster is a powerful event caused by the forces of nature, often resulting in significant change to the land and harm to people and property. These events are part of how our planet works, but they are called a disaster when they affect the places where people live and work. Learning about these forces helps us understand the world around us and how we can best prepare for them.
What Makes Something a Natural Occurrence?
Natural occurrences are events that happen on Earth without being caused by people. Our planet is constantly moving and changing through processes in the atmosphere and deep underground. An occurrence becomes a disaster only when it significantly harms human life, buildings, or the environment. For instance, a strong windstorm over an uninhabited ocean is a powerful natural occurrence, but it is not called a disaster because it does not affect any homes or people.
The science behind these events falls into two main groups: processes related to weather and processes related to the Earth’s geology. Weather-related events are driven by conditions in the atmosphere, such as temperature, wind patterns, and humidity. Geological events are caused by the movement of the Earth’s crust and the energy released deep beneath the surface, which helps scientists track and predict when and where certain powerful events are likely to happen.
Different Kinds of Natural Disasters
Many natural disasters are related to the movements of air and water, often called meteorological or hydrological events. A hurricane is a giant swirling storm that forms over warm ocean waters, bringing strong winds and heavy rainfall. These massive storms are also known as typhoons or cyclones, depending on the ocean they form in. A tornado is a rapidly spinning column of air that reaches down from a thunderstorm cloud and touches the ground, often appearing as a funnel shape.
Heavy rain can cause floods, which happen when water overflows its normal boundaries and covers land that is usually dry. Floods are the most common type of natural disaster in the United States, often resulting from rivers overflowing or melting snow. Other events are related to the earth itself, such as an earthquake, which is the sudden shaking of the ground caused by the movement of large sections of the Earth’s crust called tectonic plates. This shaking releases energy in waves that can damage roads and buildings.
Sometimes, an earthquake under the ocean floor or a large underwater landslide can create a tsunami, which is a series of large, destructive waves. A volcanic eruption occurs when an opening in the Earth’s surface allows hot, molten rock, called magma, to escape. When this molten rock reaches the surface, it becomes lava and flows down the mountain, along with ash and gas.
Staying Safe When Disaster Strikes
Knowing what to do is the best way to feel calm and prepared when learning about natural disasters. The most important step a family can take is to create and practice a family emergency plan together. This plan should include knowing how to communicate and having a safe spot to meet up if you are separated during an event.
Practicing these actions is very helpful, similar to practicing a fire drill at school. For an earthquake, the recommended action is the “Drop, Cover, and Hold On” method: immediately dropping to the floor, taking cover underneath a sturdy object, and holding onto it until the shaking stops. Preparing a small emergency kit with water, food, and flashlights also helps everyone feel ready. The safest action is always to listen carefully to the adults around you and follow official warnings.