acquired March 29, 2021

Pacaya Heats Up



Situated along the Central America Volcanic Arc, Guatemala is home to 36 volcanoes. Volcan de Pacaya is one of the most active in the country and the region. It has been erupting pretty regularly since 1961, with the most recent event starting in 2015.

In early 2021, Pacaya’s fiery reach has stretched closer to human settlements in Guatemala. For several weeks the volcano has been fueling lava fountains and flows, while spewing plumes into the air in what scientists refer to as strombolian activity. Plumes of gas and ash have risen as high as 4500 meters (13,000 feet) above sea level from the Mackenney summit crater, which stands 2500 meters tall. Lava has flowed 2 to 3 kilometers (1.5 to 2 miles) down the west flank of Pacaya.

On March 29, 2021, the Operational Land Imager (OLI) on the Landsat 8 satellite acquired data for a false-color image of the eruption. The image combines shortwave infrared and red light (OLI bands 7-6-4) to better distinguish the heat signature of volcanic lava amid the vegetation and clouds. (Europe’s Sentinel-2 got a similar false-color view on April 4, while the ASTER instrument on NASA’s Terra satellite acquired a thermal infrared image on March 5.) The natural-color image below was acquired on January 24 and provides some rare visual context for an area that is often bathed in clouds.

acquired January 24, 2021

The relatively slow-moving lava flow has branched into four arms along the western flank of Pacaya, and volcanic tremors have been nearly constant, according to Sismología Nacional de Guatemala. The molten rock has caused vegetation fires, including damage to some coffee and avocado plantations near El Patrocinio and El Rodeo.

There is some concern for communities on the western and southern flanks. About 4,000 people live within 5 kilometers (3 miles) of Pacaya; about 2.5 million people live within 30 kilometers (20 miles). In early March, Guatemalans living close to the volcano mostly refused recommendations to evacuate the area.

NASA Earth Observatory images by Lauren Dauphin, using Landsat data from the U.S. Geological Survey. Story by Michael Carlowicz.