Because Iceland is located on the mid-Atlantic Ridge, there is a high concentration of active volcanoes. On the island is 30 active volcanic systems, but only 13 of them have erupted since the settlement of Iceland. The most active of these volcanoes is Grimsvotn. Craters make up a large part of the volcanic system. These volcanoes live underneath the glaciers. When an eruption occurs, it sends thousands of tonnes of ash into the sky and it lasts for days.
Some volcanoes on the island are extinct. The volcanic mountains in Iceland number about 130. Between 1783 and 1784, there was a volcanic eruption in Iceland that caused a quarter of the Icelandic nation to die. Direct effects and indirect effects caused death, such as lava flow, illness in livestock, changes in climate, ash and poisonous gasses caused by the eruption. This is when famine struck Iceland. The massive effect spread globally. It caused global temperatures to drop. It also spewed sulfur dioxide into the Northern Hemisphere. There were crop failures in Europe and drought in India.
The largest amount of lava eruption happened in 1783 when the volcano Lakagigar erupted. One of the most famous and active volcanoes on the island was Hekla often called "the gateway to hell." Eruptions from this volcano were difficult to predict. They would last for days to a couple years. Since 874 this volcano has erupted more than 20 times. Katla is the most dangerous causing glacial river floods. These floods destroy homes and farms.
In some places on the island, the climate varies where on the coast it may be a bit warmer. It is the Central Highland where it is coldest. 1300 species of insects make their home in Iceland. The Arctic fox and polar bears live there too.
In Iceland, volcanic tourism is popular. People from near and far want to learn all about the destructive powers of Icelandic volcanoes. In this land of fire and ice you will find people skiing, hiking, driving, snowmobiling or even flying by plane to see the huge craters. The forces of nature put on a real show here. Volcanologists find this area to be a real paradise.
Being one of the most active tectonically spots on Earth, Iceland has a volcanic alert system that warns people about the next major eruption. This country is covered with monitoring devices. Some devices are used to monitor how the ground expands when it is filled with magma. There are also sensors that are used for monitoring waves moving through the Earth's crust before, during and after an eruption. There are also radars that send continuous microwave measurements to help predict the rate of ash and other particles.
Some of the more active volcanoes appear restless as any second they may erupt causing catastrophe. These volcanoes are giants. Volcano monitoring allows scientists to monitor activity even before the eruption takes place allowing time for warning. This is a relief to the people who live there and it prepares them for safety.