Hawaii's Mount Kilauea erupted Wednesday, though the main concern is not lava, but volcanic gas.
The eruption began at 4:44 a.m. Hawaii Standard Time and largely remained confined to the Halemaʻumaʻu crater, which has been closed to the public since 2007 and is within the Hawaii Volcanoes National Park. By about 3 p.m., initial lava flows were between 13 and 30 feet high and covered the crater floor, an area of about 370 acres, the U.S. Geological Survey said.
A live stream of the eruption can be seen here.
A code red alert has been issued in the area.
"Large amounts of volcanic gas — primarily water vapor (H2O), carbon dioxide (CO2), and sulfur dioxide (SO2) — are continuously released during eruptions of Kilauea volcano," the USGS said in its statement.
Volcanic smog, a haze that appears when volcanic gas mixes with the atmosphere, has been observed downwind and has the potential to cause health hazards in people and livestock and damage crops.
Other hazards include wall instability, ground cracking, rockfalls and "Pele's hair," a term used to describe glass fibers formed from gas bubbles that stretch into thin, long strands and often become airborne.