Popocatépetl

Popocatépetl was built by many eruptions, one layer on top of another.

It stands with other high volcanoes east of Mexico City.

Popocatépetl is a stratovolcano, a cone built from many layers of lava and ash. UNESCO says it stands in the Trans-Mexican Volcanic Belt, and that the hills, cones and slopes around it are of volcanic origin, mostly basalt and andesite rock.

It is part of a group of high volcanoes east of Mexico City that includes Iztaccíhuatl.

UNESCO's Los Volcanes Biosphere Reserve covers the central-eastern Trans-Mexican Volcanic Belt, the southern Sierra Nevada and the Sierra de Río Frío east of Mexico City, a landscape dominated by Iztaccíhuatl, Popocatépetl and other volcanoes. Its hills, cones and slopes are volcanic, with basalt and andesitic rocks predominating.

NASA describes Popocatépetl as a stratovolcano; its 2020 ASTER image shows a plume venting from the summit crater.

Pine forests and high, grassy meadows grow on the slopes around the volcano.

A rabbit called the volcano rabbit lives in these mountains.

UNESCO says the land around Popocatépetl changes with height, from pine and oyamel fir forests to high-mountain grasslands. This gives many kinds of plants and animals, including some found nowhere else.

Among its animals is the volcano rabbit. The forests and grasslands also help water soak into the ground and feed the water supplies of the valleys of Mexico, Puebla and Cuernavaca.

The reserve sits where the Nearctic and Neotropical regions meet, and UNESCO says its altitude-driven ecosystem gradient favors high species richness and endemic species. Ecosystems include pine, oyamel fir and high-mountain grasslands, with emblematic fauna such as the volcano rabbit (Romerolagus diazi) and rich fungal diversity.

Forests and grasslands regulate runoff, stabilize slopes and feed the aquifers that supply the Valleys of Mexico, Puebla and Cuernavaca. In this live volcanic setting, UNESCO notes, young ground supports natural disturbance and soil renewal.

Scientists watch Popocatépetl every day.

They count its puffs of steam and gas.

Mexico's National Center for Prevention of Disasters (CENAPRED) keeps watch on Popocatépetl. In February 2020, NASA reported, it recorded dozens to hundreds of steam-and-gas emissions on most days.

Satellites help too. NASA's satellites have photographed the volcano's plumes several times, such as on February 25, 2020 and January 27, 2024.

NASA's 2020 report cites the Global Volcanism Program and CENAPRED: dozens to hundreds of steam-and-gas emissions on most days in February 2020, multiple low-to-moderate gas eruptions, and occasional ash and incandescent material.

NASA notes the volcano sits between two large population centers, Mexico City and Puebla. In January 2016, according to news reports NASA cited, an eruption briefly closed Puebla's airport while workers cleared ash from the runway.

Popocatépetl is an active volcano, and scientists watch it closely.

High up, the air has less oxygen, and people can get headaches.

Because Popocatépetl is active, Mexico's disaster-prevention center watches it closely. This photo was taken from Paso de Cortés and shows the volcano's north side.

UNESCO says the land of the biosphere reserve lies between 2,589 and 5,452 meters above sea level. Places that high can cause altitude sickness. The US Centers for Disease Control and Prevention (CDC) says children are as likely to get it as adults, headache is its main sign, and going down at least 300 meters helps.

Popocatépetl is monitored by CENAPRED. UNESCO gives the Los Volcanes reserve an altitude range of 2,589 to 5,452 m, so all of it lies above the CDC's 2,450 m sleeping-altitude threshold.

The CDC's Yellow Book says any unacclimatized traveler sleeping at 2,450 m or higher is at risk of altitude illness, children are as susceptible as adults, headache is the cardinal symptom of acute mountain sickness, and a descent of 300 m or more brings rapid improvement.