Active or active volcanoes are the subject of many discussions of volcanologists. Scientists express their various views and ambiguous points of view regarding this definition. Some suggest that the active volcanoes include those whose eruption is occurring at the moment, as well as those that show all kinds of signs of activity. This may be increased or abnormal seismicity, as well as an increase in fumarole activity. For other specialists, active volcanoes are those that erupt in historical time. Different regions observe volcanic activity at certain time intervals, and they, in turn, are very different. It can be both 200 and 3000 years.
There is a program for the study of world volcanism. It is carried out by the largest research and museum complex in the world - the Smithsonian Institute. Participants in this program decided that volcanoes should be considered active if they erupted over the past 10,000 historical years.
Currently, there are about 1,500 active volcanoes on the globe. Each year, about 50 of them are erupted, and a large amount of toxic gases, ash, steam, and lava are released into the atmosphere. Accompanied by earthquakes, they can cause irreparable damage. In 2011, the world's active volcanoes erupted in Japan, Chile, Italy, Iceland and Indonesia. Most active or active volcanoes are concentrated in Hawaii and Alaska.
Volcanoes that have been sleeping for decades can suddenly wake up, as was the case in the south in central Chile. Etna 's highest volcano in Europe , located on the island of Sicily, spewed lava flows last summer.
Active volcanoes attract a lot of tourist attention. Located in an uninhabited part of the Virunga National Park of the Democratic Republic of the Congo, without presenting a threat to the endangered species of mountain gorillas, the Nyamulangira volcano intensified in the fall of 2011. It attracted a large number of tourists with its breathtaking view of the slowly flowing rivers of red-hot lava. This is a beautiful and at the same time terrifying sight. Nature does not tire of periodically reminding about its rights and that it is not a lifeless commodity. These reminders occur in the form of disasters, one of the reasons for which are the active volcanoes of the world.
A powerful Pacific ring of active volcanoes includes a large link of Kamchatka with 28 and 39 Kuril volcanoes. A large number of them are hidden under water. In an inactive state, they look quite peaceful, but do not forget about the processes taking place in their bowels. One of the largest Kamchatka active volcanoes is Shiveluch, but the highest active volcano in Eurasia is located in the Klyuchevskaya Sopka area. From the very beginning of its operation to our time, unknown long periods of its attenuation are unknown. The perfectly symmetrical, snow-covered volcano is often called the "fiery mountain." Its height fluctuates after regular eruptions. The last one, which happened in 2009, brought its peak closer to the mark of 5000 meters.
Colombian Nevado del Rus is the highest active volcano located in the Andes, and Ojos del Salado is the highest in the world. It is located on the border of Chile and Argentina in South America. At the base, its diameter is 30 km, and the height according to various sources is from 6880 m to 6908 m
Volcanoes can be not only “hot”, but also “cold” or mud. In Azerbaijan, their representative is Gobustan, which is considered therapeutic.
Active volcanoes are unusually interesting, which is confirmed by numerous facts. For example, it is known that eruptions accelerate evolutionary processes, and climatic conditions on our planet have repeatedly changed due to active volcanic activity. Animals and plants had to evolve, adapting to these changes.