Roundup of Global Volcanic Activity
Cleveland (Aleutian Islands, Alaska): AVO reported that during 29 July-4 August satellite images detected strongly elevated surface temperatures at the volcano’s summit consistent with growth of a new lava dome. A field crew working in the area on 1 August reported frequent rockfalls on the volcano. A weak infrasound signal was much smaller than the explosion detected on 21 July; the signal may have been related to gas emissions, also consistent with lava-dome effusion. A very small gas plume was visible in webcam images during 2-3 August, and steam emissions were observed on 4 August.
Nevado del Ruiz (Colombia): Sporadic ash emissions continue to occur from time to time at the volcano. A tremor episode on 6 August that started at 08:39 local time and lasted a few minutes was accompanied by the expulsion of ash that rose approx. 700 m. Light ash fall occurred in Manizales, Villamaria, Cinchina, Santa Rosa and Pereira.
Sabancaya (Peru): The volcano remains restless. A diffuse plume with light ash content is rising most of the time from the summit crater.
Shiveluch (Kamchatka): A moderately sized eruption occurred Thursday evening and produced an ash plume that rose to approx. 18,000 ft (5.4 km) altitude. Minor, near continuous ash venting has been intermittently visible on webcam imagery since.
Aso (Kyushu): The eruption from Aso volcano’s Nakadake crater continues. During the past day, several phases of ash emissions occurred. At night, incandescence can be seen at the vent. The activity is not typical strombolian with discrete explosions, but rather continuous phases of jet-like venting of ash. Its cause is probably phreatomagmatic – the release of hot ash and gas as water and magma interact at depth.
Nishino-shima (Volcano Islands, Japan): The volcano on the island continues to erupt lava flows that continue to gradually enlarge the island. The latest survey by the Japanese coast guard shows that lava flows have been traveling mostly through a tube system towards the east, where active flows continue to add land to the coast.
Manam (Papua New Guinea): Ash emissions yesterday and today produced a plume that rose to estimated 21,000 t (6.5 km) and drifted SSW. (VAAC Darwin)
Raung (East Java): Intense ash emissions continue to produce a plume that stretches hundreds of kilometers to the SW. Many flights to and from Bali were canceled or delayed today again. The detected heat emission, based on satellite data from NASA’s MODIS sensor, remains elevated, although it has decreased significantly during the past days.