For all their destructive power, most volcanic eruptions are local events.
For all their destructive power, most volcanic eruptions are local events. Lava flows tend to reach only a few miles at most, while airborne ash and soot travel a little farther. But occasionally, larger eruptions can launch particles into the stratosphere, more than 6 miles above Earth’s surface. The 1991 eruption of Mount Pinatubo in the Philippines—the world’s largest eruption in the past 100 years—is a prime example of a stratospheric eruption.
When volcanic particles reach the stratosphere they stay aloft for a long time, reflecting sunlight and temporarily cooling the planet. By understanding the history of these big eruptions, researchers can begin to place short cooling episodes and other discrete climate events into the context of large-scale climate patterns.
Researchers working at the University of Maryland, the Université Grenoble Alpes in France, the Ecole Normale Supérieure in France and the Tokyo Institute of Technology have devised a new, more accurate system for identifying large stratospheric eruptions recorded in the layers of Antarctic ice cores.
Using their method, the researchers made some important revisions to the known history of big eruptions—correcting the record on several misidentified events while discovering a few as yet unknown stratospheric eruptions. The researchers described their approach, which identifies airborne volcanic particles with a specific chemical signature, in a paper published January 28, 2019, in the journal Nature Communications.
Read more at University of Maryland
Image: This photo, taken on June 12, 1991, shows the eruption column of Mount Pinatubo on Luzon Island in the Philippines. The eruption--the largest on Earth in the past 100 years--ejected particles into the stratosphere, more than 6 miles above the planet's surface. New research uses ice core data to rewrite the past 2,600 years of large stratospheric eruptions like this one. (Credit: Dave Harlow/USGS)
