Fuego volcano injected large amounts of sulfur dioxide into stratosphere, may induce some short-term global cooling

Volcanologist Simon Carn is quoted by Smithsonian as saying “SO2 mass ejected was about ~2 orders of magnitude than the 1974 eruption, which had a significant stratospheric impact. “

It is well known that sulfur dioxide ejected into the stratosphere has a global cooling effect.

Handout picture released by the National Disaster Relief Agency of Guatemala showing the Fuego volcano erupting on June 3, 2018

From NASA:

Fuego in Guatemala is one of Central America’s most active volcanoes. For years, the towering Volcán de Fuego has puffed continuously, punctuated by occasional episodes of explosive activity, big ash plumes, lava flows, and avalanche-like debris slides known as pyroclastic flows.

Just before noon on June 3, 2018, the volcano produced an explosive eruption that sent ash billowing thousands of meters into the air. A deadly mixture of ash, rock fragments, and hot gases rushed down ravines and stream channels on the sides of the volcano. Since these pyroclastic flows often move at speeds of greater than 80 kilometers (50 miles) per hour, they easily topple trees, homes, or anything else in their path. According to news reports, more than two dozen people were killed. As a precautionary measure, thousands of other people have been evacuated.

The Visible Infrared Imaging Radiometer Suite (VIIRS) on Suomi NPP acquired this image of the ash plume at 1 p.m. local time (19:00 Universal Time) on June 3, 2018, after the ash (brown) had punched through a deck of clouds. A report from the Washington Volcanic Ash Advisory Center estimated the plume’s maximum height at 15 kilometers (9 miles). Imagery from a geostationary satellite showed winds blowing the plume to the east. The eruption deposited ash on several communities surrounding the volcano, including Guatemala City, which is 70 kilometers (40 miles) to the east.

In addition to ash, the plume contains gaseous components invisible to the human eye, including sulfur dioxide (SO2). The gas can affect human health—irritating the nose and throat when breathed in—and reacts with water vapor to produce acid rain. Sulfur dioxide also can react in the atmosphere to form aerosol particles, which can contribute to outbreaks of haze and sometimes cool the climate.

Satellite sensors such as the Atmospheric Infrared Sounder (AIRS) on the Aqua satellite and the Ozone Mapping Profiler Suite (OMPS) on Suomi NPP make frequent observations of sulfur dioxide. The map above shows concentrations of sulfur dioxide in the middle troposphere at an altitude of 8 kilometers (5 miles) as detected by OMPS on June 3.

Upon seeing data collected by AIRS several hours after the eruption that showed high levels of sulfur dioxide in the upper troposphere, Michigan Tech volcanologist Simon Carn tweeted that this appeared to be the “highest sulfur dioxide loading measured in a Fuego eruption in the satellite era.”

NASA Earth Observatory images by Joshua Stevens, using VIIRS data from the Suomi National Polar-orbiting Partnership and OMPS data from the Goddard Earth Sciences Data and Information Services Center (GES DISC). Story by Adam Voiland.


In a special bulletin from 0600 on 3 June INSIVUMEH noted increased activity at Fuego. Strong explosions were accompanied by rumbling sounds, and shock waves that vibrated local structures. Dense ash plumes rose 2.3 km above the crater and drifted SW, W, NW, and N. Pyroclastic flows descended the Seca (Santa Teresa) drainage on the W flank, and possibly other drainages, though poor weather conditions prevented clear views of the summit area. Ash plumes drifted in westerly directions, causing ashfall (on roofs and cars) in Sangre de Cristo (8 km WSW) and San Pedro Yepocapa (8 km NW). By 1000 pyroclastic flows were descending the Cenizas (SSW) drainage. Ashfall was reported in additional areas including La Soledad (10 km ESE), Quisache, and the municipality of Acatenango (8 km E).

Based on information from multiple agencies, the Washington VAAC reported an ash plume rising to 9 km (30,000 ft) a.s.l. at 1130 from an explosive eruption. In a report from 1340, INSIVUMEH described large pyroclastic flows traveling down the Seca, Cenizas, Mineral, Taniluya (SW), Las Lajas (SE), and Honda (E) drainages, producing dense ash plumes that rose 6.2 km above the summit (or 32,800 ft a.s.l.). A news article stated that the pyroclastic flows traveled at least 8 km and reached temperatures of 700 degrees Celsius. Tephra and lapilli fell in areas more than 25 km away, including in La Soledad, San Miguel Dueñas (10 km NE), Alotenango, Antigua Guatemala (18 km NE), and Chimaltenango (21 km NNE). Ashfall was reported as far away as Guatemala City, 70 km E. Explosions rattled structures within 20 km of Fuego. The La Aurora International Airport closed at 1415. Eyewitness accounts described the fast-moving pyroclastic flows inundating fields people were working in, overtaking bridges, and burying homes up to their roof lines in some areas. San Miguel Los Lotes, Alotenango, and El Rodeo (10 km SSE) were the worst affected.

According to Simon Carn, satellite data analysis showed that the event produced the highest SO2 loading measured from a Fuego eruption in the satellite era (since 1978), and therefore most likely the highest since the major 1974 eruption. He went on to note that the SO2 mass was about ~2 orders of magnitude than the 1974 eruption, which had a significant stratospheric impact. 

via Watts Up With That?

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June 9, 2018 at 04:06AM

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