When a landslide tore through a remote Alaskan valley in July, no one was there to bear witness. But hours later, geoscientist Colin Stark of the Lamont-Doherty Earth Observatory spotted the event in the pattern of seismic waves passing through the Earth’s crust. Within days, using data from earthquake sensors and satellite images, he and colleague Göran Ekström were able to estimate, from their lab in New York, the landslide’s size, and even determine its path.
This past spring’s eruption of the Eyjafjallajökull volcano in Iceland was a nightmare for travelers, but it gave scientists in Europe unprecedented access to a complex eruption right in their backyard. Old workhorses of volcanology–seismometers and GPS sensors, which detect movement of the ground–first picked up Eyjafjallajökull’s stirrings in early January. (For the record: The name is pronounced “AY-yah-fyah-lah-YOH-kuul.”) But when the volcano turned volatile in mid-April, scientists took to the skies, enlisting specially equipped planes to study the eruption and its effects on the overlying glacier. Continue reading