[Philippines] When Mount Pinatubo erupted in 1991, the amount of sulfuric ash it sent into the stratosphere cooled global ground temperatures by 1°F for the next two years. While the eruption resulted in more than 700 deaths, many scientists predicted the explosion, thus saving the lives of an estimated 5,000. Still, the eruption produced one of the most dramatic environmental scenes ever witnessed. With ash that rose 22 miles into the sky, it is considered the second largest volcanic eruption of the 20th century.

[Naples, Italy] Mt. Vesuvius has produced some of Europe's largest volcanic eruptions. In the year 79 A.D. a massive eruption from Mount Vesuvius completely destroyed the city of Vesuvius. The city was covered in 6 meters of hot ash, pumice and cinders. The ancient city has been excavated and gives us a unique look into daily life during the Roman empire. There are no other active volcano in mainland Europe like this one.

[Washington, USA] Mount St. Helens was getting ready to burst for nearly two months after being dormant for the more than 120 years. While the eruption was anticipated, the manner in which it occurred was completely unprecedented. At 8:32 a.m. on May 18, 1980, a 5.1-magnitude earthquake triggered a sideways blast that swept the mountain's north face away into a cascading landslide that shot hot ash and stone out some 15 miles at speeds of at least 300 m.p.h. At the same time, a mushroom-shaped plume of ash shot 16 miles into the air, eventually covering three states. Complete darkness blanketed Spokane, Wash., a city about 250 miles northeast of the volcano.

[Sumbawa, Indonesia] The Volcanic Explosivity Index goes up to 8. On that scale, the 1815 eruption of Mount Tambora rates a very destructive 7. Tens of thousands of people were killed by the apocalyptic eruption, subsequent tsunamis and ensuing starvation and disease. The largest volcanic eruption in recorded history changed the world's climate so much (even crops in Europe and North America failed) that 1816 became known as "the year without a summer." Tambora itself shrank several thousand feet and traded its peak for a massive crater at its summit.

[Hawaii, USA] Mauna Loa is located on the Big Island of Hawaii and in addition to being the largest, with a summit nearly 13,700 feet high, it is also one of the world's most active. Since 1843, Mauna Loa has erupted 33 times, most recently in 1984. At 60 miles long and 30 miles wide, Mauna Loa, the name of which fittingly means "Long Mountain" in Hawaiian, takes up about half of the Big Island.

[Santorini, Greece] Although the ~1630 BC eruption of Santorini is recognized as one of the most explosive volcanic eruptions in historic times, the event is only a single eruption in a continuum of eruptive activity associated with subduction. The geologic record over the past one million years indicates that less explosive Strombolian and Vulcanian eruptions have occurred at Santorini about once every 5000 years, and that Plinian-type events have occurred about once every 20,000 years.

[New Zealand] When Mt Ruapehu started to erupt in September 1995, water mixed with ash, blocks and bombs was thrown from the crater lake. Where this mixture fell outside the crater, it formed several muddy lahars that flowed down the mountainside. This photograph shows one of the first eruptions, on 23 September 1995.

[Indonesia] The Toba super-eruption was the biggest volcanic blast on Earth in the past 2.5 million years, and probably further back than that as well.

Researchers estimate some 2,000-3,000 cubic kilometres of rock and ash were thrown from the volcano when it blew its top on what is now the Indonesian island of Sumatra.

Much of that debris landed close by, piling hundreds of metres deep in places. But a lot of it would also have gone into the high atmosphere, blocking out sunlight and cooling the planet. Sulphurous gases emitted in the eruption would have compounded this effect. It is now the largest lake in Indonesia and the largest volcanic lake in the world, known as Lake Toba.