The biggest volcanic eruption ever recorded by humans was the explosion of Mount Tambora on Sumbawa Island, Indonesia, in 1815. It ranked a 7 (or "super-colossal") on the Volcanic Explosivity Index, the second-highest rating in the index.
The gas and other particles spewed high into the atmosphere during the 1991 eruption of Mount Pinatubo reduced global temperatures by about 0.9 degrees Fahrenheit (0.5 degrees Celsius) during the following year.
Lots of ash
The 1991 eruption of Mount Pinatubo ejected more than 1 cubic mile (5 cubic kilometers) of material into the air and created a column of ash that rose 22 miles (35 km) in the atmosphere.
The largest volcanic blast of the 20th century was the eruption of Novarupta one of a chain of volcanoes on the Alaska Peninsula, part of the Pacific Ring of Fire in 1912. It was a 6 (out of a possible 8) on the Volcanic Explosivity Index.
Hawaii's Kilauea volcano, one of the most active on Earth, has been erupting continuously for more than 29 years, beginning Jan. 3, 1983.
Kilauea erupted 200 years ago, sending speeding lava flows down its peaks and killing more than 400 people, including Hawaiian warriors. It was the deadliest volcanic eruption on record in what is now the United States.
Kilauea means "spewing" or "much spreading" in Hawaiian.
More than 90 percent of Kilauea's surface is covered by lava less than 1,100 years old.
Stratovolcanoes are tall, steep, conical structures that periodically erupt explosively and are commonly found where one of Earth's plates is subducting below another, producing magma along a particular zone.
The Hawaiian shield volcanoes are the largest mountains on Earth. The total height of Mauna Kea, below and above sea level, is 33,500 feet (10,210 meters), making it taller than even Mount Everest.
The largest volcanoes on Earth are shield volcanoes, which have broad, gentle slopes built by fluid basalt lavas.