Mount Kilauea Eruption
The volcanic eruption in Kilauea Volcano, Hawaii, on May 3, 2018, that destroyed dozens of structures. REUTERS/Terray Sylvester

Natural disasters are events that mostly occur without a warning, harming both property and people.

Such disasters include volcanic eruptions, earthquakes and tsunamis, and they take place due to movements of the Earth. These occur with minimum warning and are impossible to stop. However, steps can be taken to reduce damage to life and property.

In recent years, the biggest loss of life due to earthquake occurred in 2011 in Japan where almost 21,000 people died after a quake of magnitude 9 hit the coast of the Asian country, causing tsunami.

Eruption of Nyiragongo volcano, Congo, in 2002 is considered to be one of the biggest volcanic eruptions in the 21st century. It destroyed 15 percent of the city of Goma and forced the evacuation of 400,000 people.

Hurricanes and tornadoes are weather-related natural disasters that usually occur with some degree of advance warning.

Hurricane Mitch of 1998 was one of the biggest in recent years, and resulted in 19,000 deaths and an incredible amount of damage. The hurricane passed through Belize, El Salvador, Guatemala, and Nicaragua, destroying over 23,900 and hundreds of schools and bridges.

Extreme weather conditions also cause floods, landslides, famine and mudslides. Tornadoes strike as a powerful rotating mixture of wind and thunderstorm clouds and are very common in the United States, which has an average of 800 such disasters a year.

Another common natural disaster in the U.S. is wildfire, which is caused by extreme drought.

Avalanche, which refers to sliding of a large slab of snow down a mountainside, is also a natural disaster. The avalanche on Mount Kazbek, Russia, in 2002 killed 150 people and is considered one of the deadliest of the 21st century.

The first half of 2018 saw a lot of destruction around the world, right from wildfires in the U.S. to dust storms In India.

Take a look at the biggest natural disasters that hit the world in the first half of 2018.