Volcanoes are both beautiful and terrifying, especially when they are erupting like the one in Semeru. Behind its reputation, there are actually many benefits of the existence of a volcano. Anything? Here's a summary:
1. Atmospheric cooling
One short-term benefit can be observed in several major volcanic eruptions, such as the 1991 eruption of Mount Pinatubo in the Philippines, which released sulfur gases and ash into the stratosphere.
"The sulfur gas combines with the water in the atmosphere, creating microscopic droplets that can stay in the atmosphere for years. The result is a cooling of the lowest levels of the atmosphere, which is where we live and breathe," said Dr Tracy Gregg, professor of geology at the University at Buffalo.
There was a decrease in temperature of half a degree Celsius because of the eruption. "It doesn't look like much, but volcanoes are actually keeping the world temperature 2 to 3 degrees cooler," he said.
2. Water production
Over a period of 4.5 billion years, the amount of water produced by volcanoes is what provides water on Earth, says Dr Janine Krippner from Concord University.
"It comes from steam. Over time, it becomes the water that we have on this planet. Water can also come from magma," he said.
3. Fertile Land
Fertile soil is another benefit of volcanoes. "In places like Japan, Indonesia, the Philippines and Hawaii, volcanic material mixed with soil provides many important nutrients. The soil becomes very fertile for agriculture," said Krippnner.
Not only that, volcanoes also provide a good environment for the formation of new habitats for animals, plants and insects.
4. Land formation
"We see it on the big island of Kiluea in Hawaii, where when lava flows into the ocean, it creates new land. All land in Hawaii is created this way," explained Gregg. The formation process can take up to thousands of years.
5. Geothermal energy
Hot springs and geothermal energy are another advantage of volcanoes. "People are harnessing geothermal energy in places like Iceland and New Zealand," Krippnner said.
The locations on Earth with the highest underground temperatures are in areas with active or geologically young volcanoes. Active geothermal resources are usually found in volcanic areas and earthquakes are common, for example in the Ring of Fire area.
6. Valuable materials
Sulfur, precious gold and copper, is produced by volcanic activity. Diamonds are also brought to Earth's surface from layers of a rare type of magma, known as kimberlite.
"Volcanoes also provide a lot of material. This material can be mined, for example in Indonesia," said Krippner.