Roundup of Global Volcanic Activity:
Stromboli (Eolian Islands, Italy): Activity has been at relatively low to moderate levels recently. Explosions of small to medium size occur regularly from the “usual” (mainly the eastern and western) vents.
Tolbachik (Kamchatka): KVERT reports no changes in the ongoing mainly effusive eruption; tremor has remained stable (3.3 mcm/s). No significant changes were reported for either of the other currently erupting / restless Kamchatkan volcanoes:
Chirinkotan (Northern Kurils): A thermal hot spot and steam plume remain visible on satellite images (when there is no cloud cover), indicating that some activity continues at the remote volcano.
Sakurajima (Kyushu, Japan): The IAVECI 2013 conference over, activity has dropped a bit, it seems. The volcano still has a few vulcanian explosions per day, but smaller in size, and phases of near-continuous ash emissions have become a bit weaker and shorter when observed last night.
Lokon-Empung (North Sulawesi, Indonesia): An explosion occurred Monday (22 July) morning at 05:06 local time, producing an ash plume of about 1200 m height.
Popocatépetl (Central Mexico): Emissions have been up to 2 per hour on average, but remained very small. A volcano-tectonic magnitude 2.3 quake occurred at 00:47 (local time) yesterday.
Santa María / Santiaguito (Guatemala): The lava dome has been very calm during the past day. No explosions and no movement at the previously active lava flow (on the southern slope) were observed.
Pacaya (Guatemala): Seismic and surface activity have increased during the past days, characterized by the appearance of continuous tremor and more frequent strombolian explosions, the latest special bulletin of INSIVUMEH notes. This suggests a batch of fresh magma is currently rising. The Guatemalan scientists think that it is likely that strombolian activity will increase and perhaps a lava flow will appear on the flanks of the volcano in the coming days.
Fuego (Guatemala): Activity has remained low. INSIVUMEH reports only few and weak explosions (producing ash plumes up to 400 m height) and the active lava flow decreased to 50 m length.
Telica (Nicaragua): Seismic activity has decreased a bit, although small earthquakes are still frequent.
Galeras (Colombia): A magnitude 3.2 earthquake occurred under the volcano yesterday morning. The quake was felt by some nearby residents.
Reventador (Ecuador): Activity remains at high levels, characterized by small explosions and the likely effusion of lava flows. Unfortunately, near-constant cloud cover makes direct observations difficult.
Tungurahua (Ecuador): An increase in activity has occurred since yesterday. For 24 July, IGPEN reports an eruption column of steam and ash reaching 5 km above the crater drifting into westerly directions. During the past night, a further rise in activity has likely occurred, as the increasing tremor signal suggests. Weak to moderate explosion sounds could be heard overnight and ash fall was reported from El Manzano, Choglontus, Puela, Cahuaji, and in the sectors of Cevallos, Quero and Mocha.
Sabancaya (Peru): Seismic activity has picked up. A number of earthquakes in the magnitude 2-3 range have appeared recently.
Heard (Australia, Southern Indian Ocean): A single hot spot is again visible at the summit crater. It is not known what activity exactly occurs there, but it could be that there is a small lava lake or strombolian-type activity from the crater at Dawson Peak.