Natural Disasters Name: A List of Common Natural Disasters

Natural disasters are broadly categorised based on their origin. Some of the most common types of natural disasters include:

• Earthquakes: Sudden shaking of the Earth's surface caused by the movement of tectonic plates.
• Floods: An overflow of a large amount of water beyond its normal limits, especially over what is normally dry land.
• Cyclones/Hurricanes/Typhoons: Large, rotating storm systems with high-speed winds that form over warm ocean waters.
• Droughts: A prolonged period of abnormally low rainfall, leading to a shortage of water.
• Tsunamis: A series of giant waves in an ocean or a large lake caused by an underwater earthquake, volcanic eruption, or landslide.
• Landslides: The movement of rock, debris, or earth down a sloped section of land.
• Volcanic Eruptions: The release of lava, ash, and gases from a volcano.

An earthquake occurs due to the sudden movement of the Earth's tectonic plates. These massive plates are always slowly moving, but they can get stuck at their edges due to friction. When the stress on the edge overcomes the friction, there is a sudden slip, releasing a huge amount of energy in the form of seismic waves. The point inside the Earth where the earthquake begins is called the hypocentre, and the point directly above it on the Earth's surface is called the epicentre, which is where the strongest shaking is usually felt.

While both floods and tsunamis involve large amounts of water causing destruction, their causes and characteristics are very different. A flood is typically caused by excessive rainfall or overflowing rivers, leading to a gradual rise in water levels over a large area. A tsunami is caused by a sudden, massive displacement of water, usually from an underwater earthquake, and consists of a series of powerful, fast-moving waves that crash into coastal areas with immense force.

The risk of a particular natural disaster is often linked to geography. Regions located along the boundaries of tectonic plates, like the Pacific Ring of Fire, are highly prone to earthquakes and volcanic eruptions. In contrast, cyclones form over warm tropical oceans, so coastal areas in tropical and subtropical zones are most at risk. Similarly, areas in river deltas or low-lying coastal plains are more susceptible to flooding.

Human activities can significantly worsen the effects of natural disasters. For example, deforestation on hillsides removes tree roots that hold soil together, increasing the likelihood of landslides during heavy rain. Constructing buildings in flood-prone areas or on unstable coastal land increases the potential for damage and loss of life. Urbanisation, which replaces natural ground with concrete, can also increase surface runoff and lead to more severe flash floods.

No, scientists cannot accurately predict the exact time, date, and location of a specific earthquake. While they can identify high-risk seismic zones by studying fault lines and historical data, the technology to forecast an imminent earthquake does not exist. However, for other disasters like cyclones and floods, meteorological agencies can often provide warnings several days in advance by tracking weather patterns, allowing for timely evacuation and preparation.

During a flood, it is crucial to prioritise safety. Key measures include:

• Move immediately to higher ground and avoid low-lying areas or riverbanks.
• Do not attempt to walk, swim, or drive through moving floodwaters, as even a few inches can be dangerous.
• Stay away from electrical power lines and switch off the main power supply in your home if advised.
• Listen to official emergency broadcasts for updates and evacuation orders.
• Avoid contact with floodwater as it may be contaminated with sewage and harmful chemicals.