© NASAActive since 1995, Soufrière Hills in Montserrat (shown in a 2009 photo taken from the International Space Station) is one of several small volcanoes that have spit cooling sulfur particles high into the atmosphere in the last decade.
Along with sulfur emitted by coal-burning power plants, volcanic particles spewed high in the atmosphere reduced the amount of global warming otherwise expected during the 2000s, a new study finds.
Relatively small volcanic eruptions last decade sent sulfur high enough in the atmosphere to reflect sunlight and help stall a rising global temperature trend. The work, reported online July 21 in Science, suggests it doesn't take a colossal eruption for volcanoes to have a discernible influence on climate.
"If you don't include these stratospheric aerosols in the models, you're going to overestimate how much the temperature should have increased over the past decade," says team member John Daniel, an atmospheric physicist with the National Oceanic and Atmospheric Administration in Boulder, Colorado.
Scientists had known that aerosols cool the planet, and that big eruptions spew lots of aerosols up high. But nobody had calculated how smaller recent eruptions might affect climate, and many had assumed that stratospheric aerosols from volcanoes dropped essentially to zero after particles from the 1991 eruption of the Philippines' Mt. Pinatubo fell out of the atmosphere.
Comment: What was once an occasional incident has become a alarmingly regular occurrence - we're getting reports of sinkholes every other day now!
July 17: Tennessee, US: Sinkhole beside Spring Hill's new high school stirs speculation
July 14: Utah, US: Girl dies, father hurt in crash caused by sinkhole
July 14: Florida, US: Tarpon Springs homeowners wonder if homes will be swallowed by sinkhole
July 12: US: Lenoir, North Carolina sinkhole evidence of a possible wider problem
July 7: South Carolina, US: Sinkhole Closes Stephens County Boat Ramp
June 27: Australia: Enormous sinkhole swallows south-east Queensland Rainbow beach
A collection of sinkhole images from around the world