Mexico's 'smoking mountain' lives up to its name

Mexican officials have raised the alert level for the volcano, Popocatépetl, as it spews ash and steam into the air and onto nearby communities.

A farmer works his land as the Popocatepetl volcano spews a cloud of ash and steam high into the air in San Nicolas de los Ranchos, on the outskirts of Puebla. In response to the volcano's activity, officials raised the alert level, prompting school closings and the readying of emergency shelters.

REUTERS/Imelda Medina

April 19, 2012

Mexico's Popocatépetl, North America's second largest volcano, is acting up.

Beginning Monday, red-hot rock, ash, and steam have begun spewing from the volcano a half-mile into the sky. In response, Mexico's National Disaster Prevention Centre raised their alert level to stage five (out of seven).  Several schools have closed and local officials have readied emergency shelters.

Popocatépetl belongs to the group of stratovolcanos, otherwise known as composite volcanoes, which also includes the likes of Mount Shasta in California and Mount St. Helens in Washington.

French women flock to Gisèle Pelicot rape trial, ‘to show her that she’s not alone’

In general, stratovolcanos are large, steep-sided, symmetrical cones composed of "alternating layers of lava flows, volcanic ash, cinders, blocks, and bombs," according to the US Geologic Survey.

Popocatépetl is 17,900-feet tall, glacier-clad and contains a steep-walled, 800-1,500-foot-deep crater. Its name means "smoking mountain" in Nahuatl, the region's indigenous language.

Hazards created by volcanic activity like this may include ash, lahars, and pyroclastic flows. Lahars are mudflows created by water mixing with volcanic materials like ash, while pyroclastic flows are caused by superheated gas combined with rock. Pyroclastic flows are relatively rare at Popocatépetl, however.

More than 30 million people live within view of the volcano. It sits about 40 miles southeast of Mexico City, and is visible from the capital on a clear day. 

During the last major eruption of Popocatépetl in 2000, more than 50,000 people were evacuated.