Mexico Volcano Marco Calo, left, a geophysicist at the National Autonomous University of Mexico (UNAM), take a break on the slopes of the Popocatepetl volcano in ...

And even though El Popo emanates more greenhouse gases than almost any other volcano, its emissions are still a small fraction of what humans generate in nearby Mexico City. For years Calò studied ...

POPOCATÉPETL VOLCANO, Mexico (AP) — In the predawn darkness, a team of scientists climbs the slope of Mexico’s Popocatépetl volcano, one of the world’s most active and whose eruption could affect ...

POPOCATÉPETL VOLCANO, Mexico (AP) — In the predawn darkness, a team of scientists climbs the slope of Mexico’s Popocatépetl volcano, one of the world’s most active and whose eruption could affect ...