Small volcanoes make big impact on climate

It’s getting warmer, but not as fast as climate models earlier predicted. Airborne particles from volcanic activity might help explain why.

Over the past decade, the climate has not warmed as swiftly as global climate models predicted, but it hasn’t been clear what factors might be tamping down the warming. Some experts point to increased industrial emissions of sulfur dioxide from coal burning over China and India.

 Others have wondered whether sulfur emissions from volcanic activity could also play a role. However, it’s long been thought that only colossal volcanic events such as the 1991 Mt. Pinatubo eruption could release a sizable enough quantity of sulfur dioxide to affect the climate.

Astronauts aboard the International Space Station captured this striking view of Sarychev Volcano (on Kuril Islands, northeast of Japan) beginning to erupt on June 12, 2009. New research shows that even relatively small-scale volcanic eruptions can influence global climate. Image credit: NASA

A study recently published in Geophysical Research Letters has shown that small- to moderate-size volcanoes, rather than industrial emissions over Asia, have helped slow down warming over the last decade. The cooling effect of these volcanic sulfate particles, known as aerosols, has counterbalanced about 25% of the expected warming over the last decade. The study’s multi-institutional team was led by Ryan Neely, an atmospheric scientist at NCAR who began the project while at the University of Colorado Boulder (CU-Boulder).

Sulfate aerosol forms naturally in a layer of the atmosphere known as the stratosphere, which begins above the height at which commercial airliners fly. The stratospheric aerosol layer plays an important role in balancing the heat of Earth’s atmosphere as the particles act like a mirror, reflecting light back into space and preventing some of the Sun’s energy from penetrating the troposphere, where we experience weather.

Previous research indicates that the stratospheric aerosol layer has increased by 4–10% per year since 2000. But there have been conflicting theories about the source of that increase. One study suggested that this growth in stratospheric aerosol originated in China and India due to their proximity to the Asian monsoon, which can fast-track pollution upward, creating a so-called “gateway” to the stratosphere.

However, recent satellite observations have linked the growth in the aerosol layer to emissions from relatively small and frequent volcanic eruptions.

To parse the individual contributions of aerosol from industrial emissions and volcanoes, Neely and his colleagues used an array of observations, ranging from satellites to first-hand accounts, to compile data on volcanic activity across the globe over the last decade. They then turned to a new database of volcanic sulfur dioxide emissions as well as inventories of emissions from industrial activity in Asia, inputting that information into a computer model of global climate. Their work included a detailed analysis of the aerosol properties.

When they compared the model output to satellite observations, “It was clear that the volcanoes had the larger impact,” Neely says. “The anthropogenic emissions, though much larger than the amount of sulfur emitted by the volcanoes, had little or no impact on the region we looked at in this study.”

Neely cautions that, while the new study shows the importance of volcanoes on a decadal level, there is a need to learn more about their effects on year-to-year climate variability as well. “Though we show that volcanoes had the most impact in this instance, this has not and may not always be true,” he says.

Via NCAR | UCAR

Explosive Eruption at Paluweh Volcano

Paluweh Volcano, (also known as Rokatenda) one of Indonesia’s Lesser Sunda Islands, emitted a plume of gas and ash on March 26, 2013. This natural-color satellite image was collected by the Advanced Land Imager (ALI) on Earth Observing-1 (EO-1).

NASA Earth Observatory image by Jesse Allen and Robert Simmon, using EO-1 ALI data from the NASA EO-1 team. Caption by Robert Simmon.

Instrument: 

EO-1 - ALI

Activity at Tolbachik

Though some volcanic eruptions are singular events—explosions of ash and lava that begin and end suddenly—most ebb, flow, and evolve over time, as underground magma shifts and underground channels open and close. For example, Kilauea has experienced 60 distinct events during its ongoing, 30-year eruption, while Eyjafjallajökull switched from a mild, effusive eruption to a violent, explosive eruption in April 2010.

New satellite images in March 2013 revealed possible shifts in activity at Tolbachik volcano, in far eastern Russia. Tolbachik is a complex volcano on the Kamchatka Peninsula that has been erupting since late November 2012.

The eruption began with the opening of two fissures on Tolbachinsky Dol, a plateau south of the summits of Ostry Tolbachik and Plosky Tolbachik. Lava fountains spurted from the fissures, feeding lava flows that stretched at least 16.5 kilometers (10.3 miles) from their source. Within a week, emissions from the northern fissure had slowed or stopped, and the southern fissure coalesced into a single vent. Activity remained centered at the southern vent for three months.

On March 20, 2013, the natural-color satellite image above revealed a dark spot either at the site of the northern fissure or at the northern end of the original southern fissure. The area—about 290 meters (950 feet) north-south and 110 meters (360 feet) east-west— appears similar to the fresh lava flows pouring from the southern vent, and stands out from the surrounding snow. A dark shadow stretched northwest from the site, perhaps cast by a thin gas plume. These features suggest fresh lava is reaching the surface in a second location.

This image of Tolbachik was collected by the Advanced Land Imager (ALI) aboard the Earth Observing-1 (EO-1) satellite. A dense volcanic plume obscures the active southern vent, but fresh black lava flows are visible to the south. Older flows, covered in snow, reach further to the east. Flows dating from the initial days of the eruption stretch from the site labeled “northern vent” to the west, but are partially hidden by the plume and plume shadow. Volcanic cones from earlier eruptions (1970 and earlier) dot the landscape.

1. References

2. Global Volcanism Program (2012, December) Index of Monthly Reports, Tolbachik. Accessed March 25, 2013.
3. Kamchatka Volcanic Eruption Response Team (2013, March 24) VONA/KVERT Daily Report. Accessed March 25, 2013.

NASA Earth Observatory image by Jesse Allen and Robert Simmon, using EO-1 ALI data from the NASA EO-1 team. Caption by Robert Simmon.

Instrument: 

EO-1 - ALI - NASA

Restless Mount Cleveland

Mount Cleveland is a tall, symmetrical stratovolcano composed of alternating layers of hardened lava, solidified volcanic ash, and rocks thrown out by earlier eruptions. The volcano occupies the western half of Chuginadak Island—an island shaped like a giant dumbbell in the east-central Aleutian Islands. Cleveland is one of the most active volcanoes in the Aleutian Islands, but in early March 2013, authorities lowered the volcano’s alert level to Advisory, meaning volcanic activity had decreased, but it would continue to be monitored closely for potential renewed activity.
On March 14, 2013, clouds cleared enough to allow the Advanced Land Imager (ALI) on NASA’s Earth Observing-1 (EO-1) satellite an unobstructed view of Mount Cleveland. Ash stained the snow around the summit, and the volcano sent a small plume skyward, but activity was minimal compared to the eruptive activity photographed by astronauts several years earlier.

1. References

2. Global Volcanism Program (2013, March 12) Smithsonian / USGS Weekly Volcanic Activity Report. Accessed March 15, 2013.
3. Global Volcanism Program Cleveland. Smithsonian Institution. Accessed March 15, 2013.

NASA Earth Observatory image created by Jesse Allen and Robert Simmon, using Advanced Land Imager data from the NASA EO-1 team. Caption by Michon Scott.

Instrument: EO-1 - ALI  - NASA

Activity at Kizimen Volcano

Kizimen Volcano on Russia’s Kamchatka Peninsula remained active in March 2013. The Advanced Land Imager (ALI) on NASA’s Earth Observing-1 (EO-1) satellite captured this natural-color image on March 12. A plume rose from the summit, while snow covered a lava flow on the volcano’s eastern flank. That lava was actively advancing in February 2012, and still growing a year later.
Kizimen is a steep-sloped stratovolcano composed of alternating layers of volcanic ash, lava, and debris. According to the Global Volcanism Program at the Smithsonian Institution, Kizimen has a shape similar to Mount St. Helens prior to its 1980 eruption. Kizimen experienced a bout of eruptive activity in the late 1920s, then remained quiet for the rest of the 20th century. The volcano began showing signs of unrest in July 2009, with a swarm of seismic activity—up to 120 earthquakes a day. In November 2010, the volcano had a strong fissure eruption, and pyroclastic flows—avalanches of rocks and hot gases—began in February 2011.
Reports from the Kamchatka Volcanic Eruption Response Team noted that Kizimen experienced moderate seismic activity, incandescent lava extrusions, hot avalanches on the eastern and western flanks, and gas and steam eruptions in early March 2013.

1. References

2. Global Volcanism Program Kizimen Summary, Monthly Reports, and Weekly Reports. Smithsonian Institution. Accessed March 14, 2013.
3. Kamchatka Volcanic Eruption Response Team (2013, March 14) VONA/KVERT Daily Report Accessed March 14, 2013.

NASA Earth Observatory image created by Jesse Allen and Robert Simmon, using Advanced Land Imager data from the NASA EO-1 team. Caption by Michon Scott.

Instrument: 

EO-1 - ALI - NASA

Mount Etna Boils Over

After maintaining a low simmer for ten months, Italy’s Etna volcano boiled over on February 19–20, 2013, with three outbursts in 36 hours. According to the Italian Istituto Nazionale di Geofisica e Vulcanologia, each outburst (paroxysm) featured “emission of lava flows, pyroclastic flows, lahars, and an ash cloud.”
The Advanced Land Imager (ALI) on the Earth Observing-1 (EO-1) satellite captured Mount Etna on February 19 at 9:59 a.m. Central European Time, about 3 hours after the end of the first paroxysm. The false-color image combines shortwave infrared, near-infrared, and green light in the red, green, and blue channels of an RGB picture. This combination makes it easier to differentiate between fresh lava, snow, clouds, and forest.
In the image, fresh lava is bright red, as the hot surface emits enough energy to saturate the instrument’s shortwave infrared detectors but is dark in near-infrared and green light. Snow is blue-green because it absorbs shortwave infrared light, but reflects near-infrared and green light. Clouds made of water droplets (not ice crystals) reflect all three wavelengths of light similarly and appear white. Forests and other vegetation reflect near-infrared more strongly than shortwave infrared and green, and so appear green. Dark gray areas are lightly vegetated lava flows, 30 to 350 years old.

1. References

2. Abrams, M, Bianchi, R, and Pieri, D. (1996 December) Revised Mapping of Lava Flows on Mount Etna, Sicily. Photogrammetric Engineering & Remote Sensing. 62(12), 1353–1359.
3. Cooperative Institute for Research in the Atmosphere. (n.d.) Snow/Cloud Discriminator (3-color technique)—Basic Information. Accessed February 20, 2013.
4. Istituto Nazionale di Geofisica e Vulcanologia, Sezione di Catania. (2013, February 19) Etna and Stromboli update, 19 February 2013. Accessed February 20, 2013.
5. Istituto Nazionale di Geofisica e Vulcanologia, Sezione di Catania. (2013, February 20) Etna update, 20 February 2013. Accessed February 20, 2013.

• Further Reading

• Etna’s Explosive Last Three Days (Eruptions Blog)
• Tour of the Electromagnetic Spectrum (NASA Mission: Science)

NASA Earth Observatory image by Jesse Allen and Robert Simmon, using EO-1 ALI data from the NASA EO-1 team. Caption by Robert Simmon.

Instrument: 

EO-1 - ALI - NASA

Lava Flows on Tolbachik Volcano

 

Nearly three months after Tolbachik began erupting, lava continues to flow from the Kamchatkan volcano. Over time, the lava flows change location and shift across the landscape. In this image, infrared data is superimposed on a natural-color image to highlight active flows. The image was collected by the Advanced Land Imager (ALI) aboard the Earth Observing-1 (EO-1) satellite on February 14, 2013.

The infrared light detectable by some satellite sensors provides information that is invisible to the human eye. Humans see a spectrum of light in a range of colors from violet to red. The colors are related to the wavelength of the light, which also corresponds to energy. Violet light has the shortest wavelength and highest energy; red light the longest wavelength and lowest energy. Infrared light has a longer wavelength, and even lower energy than red light. Like the individual colors of the visible spectrum, infrared light is also subdivided into categories. From shortest to longest wavelength: near infrared, shortwave infrared, and thermal infrared.
Most of the light we see (and detected by satellites) is reflected light from the Sun or another source; that light bounces off a surface and into our eyes, a camera, or a satellite instrument. In addition to reflecting light, all surfaces also emit light, at a wavelength determined by temperature. The hotter the object, the shorter the wavelength and higher the energy. At room temperature, most emitted light is long wavelength thermal infrared and therefore invisible to humans. Only very hot objects emit visible light (like an electric burner or the filament of an incandescent lightbulb).

Lava hotter than 900° C (1,700° F) glows red. As it cools, lava stops glowing visibly, but will continue to glow in lower energy wavelengths of near infrared and shortwave infrared light.

On Tolbachik volcano, the Advanced Land Imager detected the infrared light emitted from recent and ongoing lava flows. Near infrared light detected by ALI is colored yellow, and shows the erupting vent and an active lava flow, open to the air. Areas glowing in shortwave infrared light, including the fringes of the active flow, are tinted red. These surfaces are hotter than the frigid winter air of Kamchatka, but cooler than the channelized flowing lava. To the east, scattered red pixels reveal residual heat on a flow formed in early February.

1. References

2. Cascades Volcano Observatory. (2002, April 12) How hot is a volcano? Accessed February 19, 2012.
3. Kamchatka Volcanic Eruption Response Team. (2013, February 18) VONA/KVERT Daily Report Accessed February 19, 2012.

NASA Earth Observatory image by Jesse Allen and Robert Simmon, using EO-1 ALI data from the NASA EO-1 team. Caption by Robert Simmon.

Instrument: 

EO-1 - ALI - NASA

Explosive Eruption at Paluweh Volcano

Although the summit of Indonesia’s Paluweh (also known as Rokatenda) is shrouded by clouds, evidence of a recent eruption is visible on the slopes of the island volcano in this satellite image. After months of rumbling, an explosive eruption occurred on February 2 and 3, 2013. Gray ash from the eruption covers the southern slopes of the peak in this natural-color image. A lighter gray swath running from the hidden summit to the ocean traces the path of a volcanic landslide, likely the remnants of a pyroclastic flow. A brand-new delta extends into the Flores Sea at the foot of the flow. To the northwest, airborne ash swirls around the island. Green vegetation appears relatively untouched, but ash has destroyed many of the island’s crops, according to the Jakarta Globe.

Erik Klemetti, author of the Eruptions Blog, suggested that the eruption may have been caused by the collapse of an unstable lava dome. The number of small tremors and emissions of ash at Paluweh increased in October 2012, and continued into February 2013, perhaps indicating growth of the lava dome. This image was collected on February 12, 2013, by the Advanced Land Imager (ALI) on the Earth Observing-1 (EO-1) satellite. According to the Darwin Volcanic Ash Advisory Center (VAAC), Paluweh has experience minor ash and gas emissions almost daily since the initial blast.

NASA Earth Observatory image by Jesse Allen and Robert Simmon, using EO-1 ALI data from the NASA EO-1 team. Caption by Robert Simmon.

Instrument: 

EO-1 - ALI - NASA

Ash and Debris on Kizimen Volcano

Hot lava, volcanic debris, and ash cover the slopes of Kizimen Volcano in these natural-color satellite images, collected 11 days apart. Both images were acquired by the Advanced Land Imager (ALI) aboard the Earth Observing-1 (EO-1) satellite. Changes visible between the two images indicate the nearly continuous activity of the volcano, located on Russia’s Kamchatka Peninsula.

Lava seeped from the summit on January 21, 2013 (top image), growing a flow that began in October 2010. It now extends all the way down Kizimen’s eastern flank. Frequent hot avalanches that spill from the summit and steep-sided lava flow leave behind deposits of dark debris. East of the volcano, a layer of tan ash covers the snowy mountains.

By February 1 (lower image) snow obscured the older ash and debris, but fresh material had already appeared. A thin layer of ash coated snow to the south, while fan-shaped debris stretched from the summit to the south and east.

1. References

2. Global Volcanism Program. (2011, January) Kizimen: Index of Monthly Reports. Accessed February 5, 2013.
3. Kamchatka Volcanic Eruption Response Team. (2013, February 4) Current Activity of the Volcanoes. Accessed February 5, 2013.

NASA Earth Observatory image by Jesse Allen and Robert Simmon, using EO-1 ALI data from the NASA EO-1 team. Caption by Robert Simmon.

Instrument: 

EO-1 - ALI - NASA

Four Erupting Volcanoes on the Kamchatka Peninsula

Bezymianny

Tolbachik

Shiveluch

Kizimen

Russia’s Kamchatka Peninsula has the highest concentration of active volcanoes on Earth. Separated by only 180 kilometers (110 miles), Shiveluch, Bezymianny, Tolbachik, and Kizimen were all erupting simultaneously on January 11, 2013.
The activity of these four volcanoes was captured during a single orbit by the Advanced Spaceborne Thermal Emission and Reflection Radiometer on NASA’s Terra satellite. The four false-color (near infrared, red, and green) images above show Shiveluch, Bezymianny, Plotsky-Tolbachik, and Kizimen in detail.
The Shiveluch and Bezymianny eruptions are both characterized by growing lava domes—thick, pasty lava that forms a mound as it is extruded.
Tolbachik, one of the few shield volcanoes on Kamchatka, is erupting in a dramatically different manner. The thin, runny lava flows easily, forming low and broad flows similar to those in Hawai’i. In this image, the lava remains hot enough to glow in near-infrared light.
Kizimen’s lava is not as viscous as that at Shiveluch and Bezymianny, but not as fluid as Tolbachik’s. The intermediate lava forms thick, blocky flows bordered by tall levees. Rocks and ash frequently fall from Kizimen’s summit and the fresh lava flow on its eastern flank, creating dark, fan-shaped debris deposits.

1. References

2. Kamchatka Volcanic Eruption Response Team. (2013, January 17) Kamchatka and the Northern Kuriles volcanoes: Erupting or Restless. Accessed January 18, 2013.
3. Klemetti, Erik. (2013, January 18) Four New Cinder Cones from the Ongoing Tolbachik Eruption in Russia. Accessed January 18, 2013.

NASA image by Robert Simmon, using data from the NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team. Caption by Robert Simmon.

Instrument: 

Terra - ASTER - NASA

Sakurajima Volcano, Kyushu, Japan

This photograph, taken from the International Space Station, highlights one of Japan’s most active volcanoes. Sakurajima began forming approximately 13,000 years ago; prior to 1914, it was an island in Kagoshima Bay. Sakurajima was joined to the mainland by the deposition of volcanic material following a major eruption in 1914.

Several craters lie near the 1,117-meter summit of Sakurajima. The northernmost crater, Kita-dake, last erupted approximately 5,000 years ago; to the south, Minami-dake and Showa craters have been the site of frequent eruptions since at least the eighth century. The ash plume visible near the volcano’s summit may have originated from either Minami-dake or Showa.

This image highlights the proximity of several large urban areas—Aira, Kagoshima, Kanoya, Kirishima, and Miyakonojo—to Sakurajima. This has prompted studies of potential health hazards presented by the volcanic ash (such as Hillman et al. 2012), and those findings are particularly important if more powerful explosive eruptive activity resumes. The Tokyo Volcanic Ash Advisory Center (VAAC) of the Japan Meteorological Agency issues advisories when eruptions occur. An advisory on the activity in this image was issued less than one hour before the astronaut took the photograph, by which time the plume tail had encountered northeast-trending upper-level winds.

1. Reference

2. Hillman, S.E., Horwell, C.J., Densmore, A.L., Damby, D.E., Fubini, B., Ishimine, Y., and Tomatis, M. (2012) Sakurajima volcano: a physico-chemical study of the health consequences of long-term exposure to volcanic ash. Bulletin of Volcanology, 74:913–930.

Astronaut photograph ISS034-E-27139 was acquired on January 10, 2013, with a Nikon D3S digital camera using a 180 millimeter lens, and is provided by the ISS Crew Earth Observations experiment and Image Science & Analysis Laboratory, Johnson Space Center. The image was taken by the Expedition 34 crew. It has been cropped and enhanced to improve contrast, and lens artifacts have been removed. The International Space Station Program supports the laboratory as part of the ISS National Lab to help astronauts take pictures of Earth that will be of the greatest value to scientists and the public, and to make those images freely available on the Internet. Additional images taken by astronauts and cosmonauts can be viewed at the NASA/JSC Gateway to Astronaut Photography of Earth. Caption by William L. Stefanov, Jacobs/ESCG at NASA-JSC.

Instrument: 

ISS - Digital Camera - NASA

Last House Standing at Royal Gardens

The late 1950s and early 1960s were boom times for developers in Hawai’i. Speculators would buy large parcels of land on what was then a sparsely-populated island, partition them into smaller lots, and sell them to buyers eager for a piece of paradise.
That’s exactly what happened at Royal Gardens, an 1,800-acre subdivision on the slopes of Kilauea, a bulging shield volcano along Hawai’i’s southeastern coast. The area boasts lush tropical forests and extraordinary views of the Pacific Ocean, and buyers didn’t seem to notice or care that the subdivision was built on a steep slope downhill from a volcano. About half to two-thirds of the people who bought land at Royal Gardens came from the continental United States and never saw the land in person before buying it.
By 1983, most of the 1,500 lots were sold and about 200 structures had been built, including 75 homes. In January 1983, lava spilled from a series of fissures along Kilauea’s East Rift Zone. By March, the volcano was pumping out enormous fountains of lava that surged as high as 650 feet (200 meters) into the air. That same month, lava made the first of numerous forays into Royal Gardens.
The top aerial photograph shows what the Royal Garden subdivision looked like on February 19, 1977. The grid-like pattern was a network of roads that had been etched into the forested landscape. Digital Globe’s Woldview-2 satellite acquired the second image on May 15, 2011. By then, lava had destroyed the majority of the subdivision, but a few areas remained unscathed.
Luck had spared Jack Thompson’s house numerous times since the eruption began, but in 2012 his luck finally ran out. Fast-moving lava erupting from the Pu‘u O‘o crater—6 kilometers (4 miles) uphill—finally overran the house on March 2, 2012. Thompson and a photographer who happened to be staying with him evacuated via helicopter just a few hours before lava consumed his property.

• References

• Earth Observatory (n.d.) Volcanic Activity at Kilauea’s Summit.
• Global Volcanism Program (2013, January 8) Kilauea. Accessed January 25, 2013.
• Hawaii Tribune Herald (2012, March 4) Lava claims final home. Accessed January 25, 2013.
• Hawaii Magazine (2012, March 4) Big Island’s Kilauea volcano lava flow consumes last Royal Gardens home. Accessed January 25, 2013.
• Hawaii Free Press (2008, January 14) Red Hot Lava Menaces Old-boy Scam. Accessed January 25, 2013.
• Oregon State (n.d.) Start of the Eruption: 1983. Accessed January 25, 2013.
• USGS Hawaiian Volcano Observatory (2013, January 8) Recent Kilauea Status Reports, Updates, and Information Releases. Accessed January 25, 2013.
• USGS Hawaiian Volcano Observatory (n.d.) Kilauea‐Maps. Accessed January 25, 2013.
• USGS Hawaiian Volcano Observatory (n.d.) Royal Gardens is no stranger to lava flows. Accessed January 25, 2013.

Aerial photograph courtesy of the United States Geological Survey. Image from WorldView-2 ©2011 by DigitalGlobe. Caption by Adam Voiland. Congratulations to Ron Schott for being the first player to solve the puzzler.

Instrument: 

Photograph - NASA

Activity at Kilauea’s Summit

The current eruption of Kilauea Volcano is one of the longest in recorded history. The false-color (near infrared, red, and green) satellite image at the top of the page shows some of the ongoing activity.

Halema’uma’u crater, near Kilauea’s summit caldera, emits a thin plume of volcanic gases including water vapor, sulfur dioxide, and carbon dioxide. Southeast of the caldera, active lava flows spread across Hawai’i’s coastal plain. Though invisible in the false-color image, the heat from the flows glows brightly in thermal infrared light (lower image).

Both images were collected on January 7, 2013, by the Advanced Spaceborne Thermal Emission and Reflection Radiometer on the Terra satellite. Vegetation, which reflects infrared light strongly, is bright red in the false-color image. Fresh lava flows (less than 50 years or so) are varying shades of black and gray. Clouds are white and ocean water is dark blue. The thermal infrared image shows temperature—cold areas are dark, while hot areas are bright.

1. Reference

2. USGS Hawaiian Volcano Observatory. (2013, January 8). Recent Kilauea Status Reports, Updates, and Information Releases. Accessed January 22, 2013.

NASA image by Jesse Allen and Robert Simmon, using data from the NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team. Caption by Robert Simmon.

Instrument: 

Terra - ASTER - NASA

Four Erupting Volcanoes on the Kamchatka Peninsula

Tolbachik

Bezymianny

Kizimen

Shiveluch

Russia’s Kamchatka Peninsula has the highest concentration of active volcanoes on Earth. Separated by only 180 kilometers (110 miles), Shiveluch, Bezymianny, Tolbachik, and Kizimen were all erupting simultaneously on January 11, 2013.
The activity of these four volcanoes was captured during a single orbit by the Advanced Spaceborne Thermal Emission and Reflection Radiometer on NASA’s Terra satellite. These four false-color (near infrared, red, and green) images show Shiveluch, Bezymianny, Plotsky-Tolbachik, and Kizimen in detail.
The Shiveluch and Bezymianny eruptions are both characterized by a growing lava dome—thick, pasty lava that forms a mound as it is extruded. Tolbachik, one of the few shield volcanoes on Kamchatka, is erupting in a dramatically different manner. The thin, runny lava flows easily, forming low and broad flows similar to those in Hawai’i. In this image the lava remains hot enough to glow in near-infrared light.
Kizimen’s lava is not as viscous as that at Shiveluch and Bezymianny, but not as fluid as Tolbachik’s. The intermediate lava forms thick, blocky flows bordered by tall levees. Rocks and ash frequently fall from Kizimen’s summit and the fresh lava flow on its eastern flank, creating dark, fan-shaped debris deposits.

1. References

2. Kamchatka Volcanic Eruption Response Team. (2013, January 17) Kamchatka and the Northern Kuriles volcanoes: Erupting or Restless. Accessed January 18, 2013.
3. Klemetti, Erik. (2013, January 18) Four New Cinder Cones from the Ongoing Tolbachik Eruption in Russia. Accessed January 18, 2013.

NASA image by Robert Simmon, using data from the NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team. Caption by Robert Simmon.

Instrument: 

Terra - ASTER - NASA

Gas emissions at Volcán Copahue

With a history of eruptions throughout the past century, Volcán Copahue showed new signs of life in late 2012 and early 2013. Copahue awoke on December 22, 2012, with a steady volcanic tremor and a few brief explosions.

SERNAGEOMIN, the Chilean National Service of Geology and Mining, reported that the eruption was likely caused by water vaporizing as it interacted with magma rising inside the volcano. (Called a phreatic eruption by volcanologists.) Since then, SERNAGEOMIN described intermittent steam and gas plumes, accompanied by continuing earthquakes. The earthquakes suggest that magma is fracturing rock as it rises from beneath the volcano.

Volcán Copahue is a composite volcano located in the Andes, on the border of Chile and Argentina. This natural-color satellite image shows a blue-tinted gas plume streaming toward the east. The nearest settlement is Caviahue, an Argentinian ski resort. The image was acquired by the Advanced Land Imager (ALI) on Earth Observing-1 on January 5, 2013.

NASA Earth Observatory image by Jesse Allen and Robert Simmon, using EO-1 ALI data from the NASA EO-1 team. Caption by Robert Simmon, within input from Erik Klemetti, Denison University/Eruptions Blog.

Instrument: 

EO-1 - ALI - NASA

30th Anniversary of the Pu’u ’O’o Eruption on Kilauea

Just after midnight on January 3, 1983, a small fissure opened within Napau Crater on Kilauea Volcano, spewing red-hot lava. Within hours, additional fissures stretched 6 kilometers (4 miles) down the volcano’s East Rift Zone. Thirty years later, the Pu’u ’O’o-Kupaianaha eruption continues, making it the longest eruption at Kilauea in recorded history.

Since the eruption began in 1983, lava has poured almost continuously from a cluster of vents on the eastern flank. Through 2011, fresh lava had covered 124.6 square kilometers (48.1 square miles) of the Big Island of Hawai’i. Activity has occurred during 60 distinct events, separated by shifts in the location or behavior of erupting lava. Most of these events have been centered at Pu’u ’O’o, a volcanic cone built from successive lava fountains and flows. The 60th eruptive episode began in March 2011 and was ongoing through January 4, 2012. It consists of a lava pond within Pu’u ’O’o, and a steady effusion of lava that stretches 10 kilometers (6 miles) to the Pacific Ocean.

These images—a natural-color satellite image from June 6, 2011, and a black-and-white aerial photograph from March 25, 1977—show the landscape surrounding Napau Crater and Pu’u ’O’o. Lavas of different ages cover the surface. Lava flows that are more than a century old are covered by a dense forest (green in the 2011 image) of ohia lehua and tree ferns. Flows from eruptions in 1965, 1968, and 1969 are much lighter than the forest in the 1977 image, but difficult to differentiate from one another.

The 2011 image shows dramatic changes in the landscape. Weathered lava from the initial Napau Crater vent is almost indistinguishable from the older (1968 and 1969) lavas that cover most of the crater floor. In January 1997, a fresh line of fissures opened within Napau Crater, erupting lava during episode 54 of the Pu’u ’O’o-Kupaianaha eruption. Additional cracks and fissures split the earth between Napau Crater and Pu’u ’O’o in the March 2011 Kamoamoa Fissure Eruption (Episode 59), spreading black lava through the forest. Scorched forest appears reddish-brown along the edges of the lava flows.

Since March 9, 2011, lava flows have originated from Pu’u ’O’o (image upper right). A lava pond is visible within the crater, and a system of lava tubes carries molten rock underground to the southeast. Brown lavas surrounding the crater flowed directly from the lava pond.

These overlapping flows help illustrate the formation of the Hawaiian Islands as a whole. Each island was gradually built from many individual eruptions over tens of thousands of years—a blink in geological time. Kilauea is still in the early stages of its life, and will continue to erupt and grow.

1. References

2. National Park Service. (2007, February 9) Forests of Hawaii National Park. Accessed January 4, 2012.
3. Wolfe, E. W., ed. (1988) The Pu’u ’O’o eruption of Kilauea Volcano, Hawaii; episodes 1 through 20, January 3, 1983, through June 8, 1984. United States Geological Survey.
4. United States Geological Survey. (2012) Pu’u ’O ’o-Kupaianaha Eruption statistics, 1983 through 2011. Accessed January 4, 2012.

1. Related Reading

2. Hawai’i Volcanoes National Park
3. Pu’u ’O’o: Three-decade eruption of Kilauea yields scientific discoveries. (Hawaii Tribune-Herald)
4. USGS Hawaiian Volcano Observatory

Satellite image by Robert Simmon, based on Worldview-2 data copyright 2011 DigitalGlobe. Aerial photograph from the USGS Earth Explorer. Caption by Robert Simmon.

Instrument: 

DigitalGlobe - WorldView-2 - NASA

Ash Emission from San Cristóbal Volcano

In the waning days of 2012, a series of explosions and ash emissions occurred at Nicaragua’s San Cristóbal Volcano. Small eruptions are relatively common at San Cristóbal, which has been restless since 1971.
This natural-color image was captured on December 27, 2012, by the Moderate Resolution Imaging Spectroradiometer on NASA’s Aqua satellite. At the time, the Washington Volcanic Ash Advisory Center reported that the ash plume was at an altitude of 14,000 feet (4,300 meters), about 8,300 feet (2,500 meters) above San Cristóbal’s summit.

NASA image courtesy Jeff Schmaltz, LANCE MODIS Rapid Response. Caption by Robert Simmon.

Instrument: 

Aqua - MODIS

Eruption of Tolbachik Volcano

After more than a month of eruption, lava continues to flow from Tolbachik, one of many active volcanoes on Russia’s Kamchatka Peninsula. The current eruption at Tolbachik began on November 27, 2012. Lava flowed up to 20 kilometers (12 miles) from a line of fissures on the volcano’s southern flank. Since then, some of the lava has cooled enough to allow snow to accumulate. Snow-covered lava flows appear gray in this natural-color satellite image. Fresher lava appears black. A faint orange glow at the head of the northern flow marks the location of an erupting fissure.

The image was collected on December 22, 2012, by the Advanced Land Imager (ALI) on the Earth Observing-1 (EO-1) Satellite. According to the Kamchatka Volcanic Eruption Response Team (KVERT) the eruption continued through December 30, 2012.

NASA Earth Observatory image by Jesse Allen and Robert Simmon, using EO-1 ALI data from the NASA EO-1 team and the USGS Global Visualization Viewer. Caption by Robert Simmon.

Instrument: 

EO-1 - ALI - NASA

Payún Volcanic Field

Situated in the southern Andes Mountains, the Payún volcanic field of Argentina is a complex landscape that formed over hundreds of thousands of years. Sprawling over 5,200 square kilometers (2,000 square miles), Payún is a massive shield volcano—a broad formation resembling an ancient warrior shield.
This false-color image is a composite of observations acquired on February 7 and March 20, 2001 by the Enhanced Thematic Mapper Plus on the Landsat 7 satellite. It was made from a combination of visible and infrared light, where green indicates vegetation, black indicates lava flows, and orange is bare rock rich in iron oxides.

Part of the back-arc volcanism of the Andes, Payún lies about 530 kilometers (330 miles) east from where the Nazca plate subducts below the South America plate. Not surprisingly, a volcanic zone extends over some 1,000 kilometers (600 miles) north-to-south in this region. According to a study published in 2010, the regional geology and chemical composition of the rocks indicate that the volcanic field likely formed within the past 300,000 years.

The dominant feature of the volcanic field is Payún Matru, an elliptical caldera measuring roughly 9 by 7 kilometers (6 by 4 miles). Geologists surmise that the caldera formed after the old magma chamber emptied and the summit collapsed. Southwest of the caldera is a stratovolcano composed of alternating layers of compacted ash, hardened lava, and rocks ejected during previous eruptions. This stratovolcano, Payún, rises to 3,680 meters (12,073 feet) above sea level. (The entire volcanic field sits at 2,000 meters, or 6,600 feet.)
The stratovolcano may be the most prominent feature in the volcanic field but it is by no means the only one. More than 300 eruptive features litter the shield volcano, most of them occupying an east-west line. West of Payún Matru is an area known as Los Volcanes, a mass of strombolian cones and basaltic lava flows.

1. References

2. Germa, A., Quidelleur, X., Gillot, P.Y., Tchilinguirian, P. (2010) Volcanic evolution of the back-arc Pleistocene Payún Matru volcanic field (Argentina). Journal of South American Earth Sciences, 29(3), 717&nash;730.
3. Global Volcanism Program. Payún Matru. Smithsonian Institution. Accessed November 21, 2012.

Image courtesy Michael P. Taylor, Landsat Data Continuity Mission Project Office, NASA Goddard Space Flight Center. Caption by Michon Scott with information from Michael Abrams, NASA Jet Propulsion Laboratory.

Instrument: 

Landsat 7 - ETM+ - NASA

Weird Underwater Volcano Discovered Near Baja

Unlike most deep-sea basalt lavas, the rhyolitic lavas on the Alarcon Rise were very thick and pasty, like chunky peanut butter. As they emerged from the underwater volcano, they formed large, angular blocks, some of which tumbled down the sides of the volcano, eventually covering the sides of the dome in talus.

CREDIT: (c) 2012 MBARI

SAN FRANCISCO — Scientists have discovered one of the world's weirdest volcanoes on the seafloor near the tip of Baja, Mexico.

The petite dome — about 165 feet tall (50 meters) and 4,000 feet long by 1,640 feet wide (1,200 m by 500 m) — lies along the Alarcón Rise, a seafloor-spreading center. Tectonic forces are tearing the Earth's crust apart at the spreading center, creating a long rift where magma oozes toward the surface, cools and forms new ocean crust.

Circling the planet like baseball seams, seafloor-spreading centers (also called midocean ridges) produce copious amounts of basalt, a low-silica content lava rock that makes up the ocean crust. (Silica, or silicon dioxide, is the main component of quartz, one of the most common minerals on Earth.)

But samples from the newly discovered volcano are strangely rhyolite lava, and have the highest silica content (up to 77 percent) of any rocks collected from a midocean ridge, said Brian Dreyer, a geochemist at the University of California, Santa Cruz. The results were presented last week at the annual meeting of the American Geophysical Union. [50 Amazing Volcano Facts]

'A total surprise'

Researchers with the Monterey Bay Aquarium Research Institute (MBARI) discovered the volcano this spring, during a three-month expedition to the Gulf of California, the warm stretch of water that separates Baja from mainland Mexico. A remote-control vehicle explored the volcano, which is 7,800 feet (2,375 m) below the surface, and brought samples back to the ship.

"When we picked up the rocks and got them back on the ship, we immediately noticed that they were very low density, and they were very light, glassy and gray. They were not the usual dark, black, shiny basalts," Dreyer told OurAmazingPlanet. "So we immediately knew that something was unusual."

The volcano is primarily rhyolite and a silicic lava called dacite, said MBARI geologist Jennifer Paduan. "To find this along a midocean ridge is a total surprise," she told OurAmazingPlanet.

Boulders and blocks the size of cars and small houses littered the steep slopes of the dome, the robot's video camera showed. The gravelly debris is made of lava that resembles the ragged surface of a'a (rough, rubbly or blocky lava). The flows would have been deposited via large, avalanchelike deposits, Paduan wrote on the expedition's blog. A few ridges were composed of very strange, steeply dipping, lineated flows very different from the pillow-style appearance of deep-sea basalt, she wrote.

The researchers don't yet know how the age of the volcano because their samples haven't finished undergoing the necessary tests. The dome is probably several thousand years old, MBARI geologist David Clague said in an email.

Could it go boom?

Of more concern is the evidence for explosive volcanism, which is typical of rhyolite volcanoes, Paduan said.
"It's only 100 kilometers [60 miles] from land. When the sun is setting, you can see Cabo," she said. Both the Baja Peninsula and mainland Mexico near Alarcón Rise have cities and luxury resorts. The Gulf of California is also home to endangered sea life.

Rhyolite lava carries more gas and volatiles (things that are likely to cause explosions) than basalt, and when magma meets water, it vaporizes instantly, driving an even more explosive eruption.

These maps show the location of the Alarcón Rise, a 31-mile-long (50 kilometer) spreading center at the mouth of the Gulf of California. Along ocean spreading ridges like the Alarcón Rise, the seafloor is splitting apart as lava wells up from underneath.

CREDIT: (c) 2012 MBARI

"There's definitely explosive deposits there, and that is of extreme concern, given that the ridge is so close to land and the tsunami potential of a big explosion there," Paduan said. "We don't know how explosive, and that is something we are definitely trying to figure out."

The researchers also found Pele's seaweed, or limu o pele, at another location on the 30-mile-long (50 km) ridge. These are little fragments of lava formed from explosive magmatic gas bubbles that implode when they hit cold seawater. "We did find evidence of mildly explosive eruptions on the ridge," Paduan said.

Why is it there?

Rhyolites have been found on spreading centers, but only above hot spots, such as in Iceland and the Galapagos Islands, Dreyer said. Hot spots are plumes that bring magma to the surface from deep within Earth's mantle. There is no hot spot under the Alarcón Rise, he said.

Rhyolite lava typically occurs only on continents, such as in Mount St. Helen's growing dome in Washington. One possible explanation for the bizarre composition of the Alarcón dome is that continental crust snuck into the molten rock below — the spreading center is young, and continental crust lies close by. But tests of different isotopes (versions of elements with differing numbers of neutrons in the cores) in the lava samples revealed no evidence of contamination by continental crust, Dreyer said.

MBARI researchers used the “manipulator arm” on ROV Doc Ricketts to collect rock samples from the rhyolite dome. CREDIT: (c) 2012 MBARI

Another discarded idea was that a cold spot underlying the ridge cooled and crystallized the magma chamber that fed the volcano, leaving only a high-silica melt behind. The team's current hypothesis is that the magma source had a high concentration of volatiles like water, sulfur and chlorine, maybe from an influx of seawater.

"It's a work in progress, but we have found some of the glassy volcanic debris surrounding this feature has water concentrations of up to eight percent, which is pretty unusual for a spreading center," Dreyer said.

The Alarcón Rise drifts apart at a relatively slow 2 inches (5 centimeters) a year. The segment is bounded by the Pescadero transform fault to the north and the Tamayo transform fault to the south, and is the northern extension of the East Pacific Rise. The vast majority of lava flows along the ridge are basalt. The rhyolite dome is about 5.5 miles (9 km) south of the Pescadero transform fault.

- OurAmazingPlanet