A satellite captured the erupting of the Okmok Caldera volcano on Umnak Island in Alaska in July 2008. The volcano spewed both steam and ash. NASA/AP hide caption
Iceland's Volcanic Eruption And Its Aftermath A volcanic eruption in Iceland on April 14 sent a plume of volcanic ash more than 30,000 feet into the air. The ash, which has drifted south and east, has snarled air traffic across Europe, with massive flight delays that have had reverberations around the world.
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Iceland's Volcanic Eruption And Its Aftermath
The ash from a volcanic eruption in Iceland April 14 has resulted in massive flight delays.
This infrared image shows ash spewing out of Iceland's Eyjafjallajokull volcano. It was taken April 17 by a NASA spacecraft. Hotter areas, shown in red, can be seen at the ash plume's base. NASA/JPL/EO-1 Mission/GSFC/Ashley Davies hide caption
Korean Air cargo planes sit idle on the tarmac at the Incheon International Airport in Incheon, west of Seoul, South Korea, on Monday. Every day, on average, 10,000 tons of goods are airfreighted between Asia and Europe. But none of that has moved for the past week after Iceland's volcanic eruption. Lee Jin-man/AP hide caption
An empty runway at Edinburgh airport, where flights were canceled because of volcanic ash from Iceland. The situation is bad, but experts say it could be much worse. Jeff J Mitchell/Getty Images hide caption
Stranded airline passengers queue for information at El Prat international airport in Barcelona, Spain. All flights in and out of Barcelona's El Prat and 16 other Spanish airports have been grounded by the volcanic ash drifting across Europe. Jasper Juinen/Getty Images hide caption
The MODIS instrument on NASA's Terra satellite captured an ash plume from the Eyjafjallajokull volcano on Friday. Though satellite images can tell scientists where the ash is, they don't help forecasters determine how much ash is in the air — or at what point it becomes a hazard to airplanes. MODIS Rapid Response Team/NASA via Getty Images hide caption
Researchers Evgenia Ilyinskaya and Asgerdur Sigurdardottir sweep up volcanic ash from a small bridge just south of the Eyjafjallajokull volcano. The ash will be taken back to the University of Iceland for analysis. Joe Palca/NPR hide caption