People around the world watched in awe at satellite images of spectacular underwater volcanoes erupting in giant mushroom clouds in the Pacific Ocean. Many wondered why the explosion was so large, how the resulting tsunami traveled so far, and what happened next. Shane Cronin, a New Zealand scientist and professor of volcanology at the University of Auckland, and Emily Lane, a tsunami expert at the National Institute of Water and Atmospheric Research, helped explain. explosive but brief
Saturday’s eruption was incredibly explosive, but also relatively short-lived. The plume rose more than 30 kilometers (19 miles) into the air, but the eruption only lasted about 10 minutes, unlike some larger eruptions that can last for hours. Cronin said Hunga Tonga’s Hungaha Apai eruption was one of the largest in the world in the past 30 years, with heights of ash, steam and gas comparable to the 1991 eruption of Mount Pinatubo. Philippines, killing hundreds.
Why is it so big?
The magma inside the volcano is under enormous pressure and contains gas. Cracks in the rock can cause a sudden drop in pressure that expands the gas and blasts the magma. Cronin said the crater is located about 200 meters (650 feet) below the surface of the sea, a kind of Goldilocks depth for a big bang, where sea water pours into the volcano and turns into steam immediately, adding to the explosion’s rapid expansion and energy. Anything Both deeper and extra water pressure will help control the eruption. Farflung Tsunami
To the surprise of many scientists, a single eruption could have produced a Pacific tsunami of about 1 meter (3 feet) that destroyed ships in New Zealand and caused an oil spill and two drownings in Peru. Oceanwide tsunamis are typically triggered by earthquakes that span large areas, rather than a single volcano, essentially a small point in the ocean, Lane said. She said there may be other factors at play, such as the collapse of the volcano’s underwater flank and displacing water. One interesting theory, she said, is that a shock wave, or sonic boom, from the volcano, which circled the world twice, may have injected more energy into the tsunami wave.
Complete News Source : Hindustan Times
