A team of chemists from the U.S. and France examining ice-core samples have found large amounts of volcanic sulfuric acid - compelling evidence of a previously undocumented large volcanic eruption 200 years ago. The discovery helps explain why the decade from 1810 to 1819 is the coldest on record for the last 500 years.
The discovery was made after analyzing chemicals in ice samples from Antarctica and Greenland in the Arctic. The year-by-year accumulation of snow in the polar ice sheets serves as a record of what takes place in the atmosphere.
"We've never seen any evidence of this eruption before in the glacial record," said Mark Thiemens, dean of the Division of Physical Sciences at UCSD and a co-author of the study. "But if you look at the size of the signal we found in the ice cores, it had to be huge ... bigger than the 1991 eruption of Mount Pinatubo in the Philippines, which killed hundreds of people and affected climate around the world."
The discovery is published in the journal Geophysical Research Letters.
The discovery was made after analyzing chemicals in ice samples from Antarctica and Greenland in the Arctic. The year-by-year accumulation of snow in the polar ice sheets serves as a record of what takes place in the atmosphere.
"We've never seen any evidence of this eruption before in the glacial record," said Mark Thiemens, dean of the Division of Physical Sciences at UCSD and a co-author of the study. "But if you look at the size of the signal we found in the ice cores, it had to be huge ... bigger than the 1991 eruption of Mount Pinatubo in the Philippines, which killed hundreds of people and affected climate around the world."
The discovery is published in the journal Geophysical Research Letters.
