s4cnnd1imema9

April 2019, ScientificAmerican.com 17

EARTH SCIENCES AND IMAGE ANALYSIS LABORATORY AND NASA’S JOHNSON SPACE CENTER

EARTH SCIENCE

Spying

Volcanoes

from Space

An orbiting observatory

monitors signs of eruptions

every one to two hours

Scientists are zooming out to get a more

complete global view of volcanic erup-

tions—1.6 million kilometers out, to be pre-

cise. That is the distance to the Deep Space

Climate Observatory (DSCOVR), a satellite

originally conceived by former vice presi-

dent Al Gore. Using an instrument onboard

DSCOVR that can detect gases belched by

volcanoes, researchers can now take snap-

shots of eruptions every one to two hours.

Monitoring these events, which often spew

ash that can trigger engine failure in air-

planes, can help scientists quickly pinpoint

potentially dangerous airspace.

Many of Earth’s roughly 1,500 potential-

ly active volcanoes are in remote areas, so

it can be difficult to regularly study ongoing

eruptions or identify new ones, says Simon

Carn, a volcanologist at Michigan Techno-

logical University. “U.S. volcanoes are pret-

ty well monitored, but elsewhere it’s a dif-

ferent story,” Carn adds. “There’s definitely

a need for satellite monitoring.”

Carn and his colleagues used DSCOVR’s

Earth Polychromatic Imaging Camera

(EPIC) to observe 16 eruptions. They col-

lected ultraviolet measurements of sulfur

dioxide (SO 2 ), a gas frequently emitted by

volcanoes. Sulfur dioxide is the easiest vol-

canic gas to measure because it is relatively

rare in the atmosphere, Carn says. The

EPIC observations provided a new view of

Earth’s surface every 68 to 110 minutes—

much more frequently than most other

ultraviolet satellite instruments. “Eruptions

can evolve rapidly, so the higher the fre-

quency of observations, the better our abil-

ity to track them,” Carn says.

EPIC captured SO 2 measurements just

a few hours after the start of several erup-

tions; it also revealed changes other satel-

lites did not detect, the researchers report-

ed last October in Geophysical Research

Letters. For instance, EPIC showed that the

eruption of Tinakula on the South Pacific’s

Solomon Islands on October 20, 2017,

actually consisted of two separate explo-

sive events that released different amounts

of sulfur dioxide.

This work represents a “significant step

forward” in tracking volcanic clouds, says

Andrew Hooper, a volcanologist at the

University of Leeds in England, who was

not involved in the research. The observa-

tions, he states, “could ultimately help mit-

igate the impacts of volcanic eruptions.”

Currently DSCOVR transmits data to

Earth only when the satellite is in view of

receiver antennas in Virginia and Alaska.

Installing more receivers around the globe

would allow scientists to collect and ana-

lyze measurements nearly instantaneously,

Carn says, noting that “we’re a day or two

behind real time.” — Katherine Kornei

Astronaut image of the Tinakula

volcano on the Solomon Islands

April 2019, ScientificAmerican.com 17

EARTH SCIENCES AND IMAGE ANALYSIS LABORATORY AND NASA’S JOHNSON SPACE CENTER

April 2019, ScientificAmerican.com 17

EARTH SCIENCES AND IMAGE ANALYSIS LABORATORY AND NASA’S JOHNSON SPACE CENTER

EARTH SCIENCE

Spying

Volcanoes

from Space

An orbiting observatory

monitors signs of eruptions

every one to two hours

Scientists are zooming out to get a more

complete global view of volcanic erup-

tions—1.6 million kilometers out, to be pre-

cise. That is the distance to the Deep Space

Climate Observatory (DSCOVR), a satellite

originally conceived by former vice presi-

dent Al Gore. Using an instrument onboard

DSCOVR that can detect gases belched by

volcanoes, researchers can now take snap-

shots of eruptions every one to two hours.

Monitoring these events, which often spew

ash that can trigger engine failure in air-

planes, can help scientists quickly pinpoint

potentially dangerous airspace.

Many of Earth’s roughly 1,500 potential-

ly active volcanoes are in remote areas, so

it can be difficult to regularly study ongoing

eruptions or identify new ones, says Simon

Carn, a volcanologist at Michigan Techno-

logical University. “U.S. volcanoes are pret-

ty well monitored, but elsewhere it’s a dif-

ferent story,” Carn adds. “There’s definitely

a need for satellite monitoring.”

Carn and his colleagues used DSCOVR’s

Earth Polychromatic Imaging Camera

(EPIC) to observe 16 eruptions. They col-

lected ultraviolet measurements of sulfur

dioxide (SO 2 ), a gas frequently emitted by

volcanoes. Sulfur dioxide is the easiest vol-

canic gas to measure because it is relatively

rare in the atmosphere, Carn says. The

EPIC observations provided a new view of

Earth’s surface every 68 to 110 minutes—

much more frequently than most other

ultraviolet satellite instruments. “Eruptions

can evolve rapidly, so the higher the fre-

quency of observations, the better our abil-

ity to track them,” Carn says.

EPIC captured SO 2 measurements just

a few hours after the start of several erup-

tions; it also revealed changes other satel-

lites did not detect, the researchers report-

ed last October in Geophysical Research

Letters. For instance, EPIC showed that the

eruption of Tinakula on the South Pacific’s

Solomon Islands on October 20, 2017,

actually consisted of two separate explo-

sive events that released different amounts

of sulfur dioxide.

This work represents a “significant step

forward” in tracking volcanic clouds, says

Andrew Hooper, a volcanologist at the

University of Leeds in England, who was

not involved in the research. The observa-

tions, he states, “could ultimately help mit-

igate the impacts of volcanic eruptions.”

Currently DSCOVR transmits data to

Earth only when the satellite is in view of

receiver antennas in Virginia and Alaska.

Installing more receivers around the globe

would allow scientists to collect and ana-

lyze measurements nearly instantaneously,

Carn says, noting that “we’re a day or two

behind real time.” — Katherine Kornei

Astronaut image of the Tinakula

volcano on the Solomon Islands

sad0419Adva3p.indd 17 2/20/19 5:01 PM

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Untitled-666 1 19/02/2019 20:

Untitled-2 1 2/19/19 4:05 PM

EARTH SCIENCE

Spying

Volcanoes

from Space

An orbiting observatory

monitors signs of eruptions

every one to two hours

Scientists are zooming out to get a more

complete global view of volcanic erup-

tions—1.6 million kilometers out, to be pre-

cise. That is the distance to the Deep Space

Climate Observatory (DSCOVR), a satellite

originally conceived by former vice presi-

dent Al Gore. Using an instrument onboard

DSCOVR that can detect gases belched by

volcanoes, researchers can now take snap-

shots of eruptions every one to two hours.

Monitoring these events, which often spew

ash that can trigger engine failure in air-

planes, can help scientists quickly pinpoint

potentially dangerous airspace.

Many of Earth’s roughly 1,500 potential-

ly active volcanoes are in remote areas, so

it can be difficult to regularly study ongoing

eruptions or identify new ones, says Simon

Carn, a volcanologist at Michigan Techno-

logical University. “U.S. volcanoes are pret-

ty well monitored, but elsewhere it’s a dif-

ferent story,” Carn adds. “There’s definitely

a need for satellite monitoring.”

Carn and his colleagues used DSCOVR’s

Earth Polychromatic Imaging Camera

(EPIC) to observe 16 eruptions. They col-

lected ultraviolet measurements of sulfur

dioxide (SO 2 ), a gas frequently emitted by

volcanoes. Sulfur dioxide is the easiest vol-

canic gas to measure because it is relatively

rare in the atmosphere, Carn says. The

EPIC observations provided a new view of

Earth’s surface every 68 to 110 minutes—

much more frequently than most other

ultraviolet satellite instruments. “Eruptions

can evolve rapidly, so the higher the fre-

quency of observations, the better our abil-

ity to track them,” Carn says.

EPIC captured SO 2 measurements just

a few hours after the start of several erup-

tions; it also revealed changes other satel-

lites did not detect, the researchers report-

ed last October in Geophysical Research

Letters. For instance, EPIC showed that the

eruption of Tinakula on the South Pacific’s

Solomon Islands on October 20, 2017,

actually consisted of two separate explo-

sive events that released different amounts

of sulfur dioxide.

This work represents a “significant step

forward” in tracking volcanic clouds, says

Andrew Hooper, a volcanologist at the

University of Leeds in England, who was

not involved in the research. The observa-

tions, he states, “could ultimately help mit-

igate the impacts of volcanic eruptions.”

Currently DSCOVR transmits data to

Earth only when the satellite is in view of

receiver antennas in Virginia and Alaska.

Installing more receivers around the globe

would allow scientists to collect and ana-

lyze measurements nearly instantaneously,

Carn says, noting that “we’re a day or two

behind real time.” — Katherine Kornei

Astronaut image of the Tinakula

volcano on the Solomon Islands

sad0419Adva3p.indd 17 2/27/19 5:05 PM

© 2019 Scientific American