Roundup of Global Volcanic Activity:
El Hierro (Canary Islands, Spain): The number of earthquakes has increased from averages of 5-10 to about 30 during the past few days. The location of the recent quakes is in a N-S elongated layer about 10-12 km depth in the western part of the island under the El Golfo bay. So far, no quakes above magnitude 3 have occurred.
Tolbachik (Kamchatka): KVERT reports continuing lava effusion, but the slowly decreasing trend of tremor (2.1 mcm/s today) suggests that an end of the eruption is (slowly) approaching.
Kilauea (Hawai’i): The eruption continues with no significant changes; lava continues to flow into the ocean.
The lava lake inside Halema’uma’u crater at the summit caldera remains active with fluctuating levels.
Veniaminof (Alaska Peninsula, USA): A surge of activity seems to be taking place. Both visual and seismic activity have increased over the past 24 hours. An intermittent steam and ash plume has been observed rising to about 12,000 ft (3.6 km) asl. yesterday drifting into westerly directions.
Popocatépetl (Central Mexico): Activity has remained more or less at similar levels during the past days. During 11-12 August, CEAPRED reported 88 mostly weak emissions and a stronger explosion yesterday morning that produced an ash plume rising about 2.5 km above the crater.
Santa María / Santiaguito (Guatemala): Activity remains relatively elevated with occasional explosions producing ash plumes up to about 1 km height. Fine ash fall occurs in areas downwind in up to 10 km distance. The risk of lahars (mud flows) triggered by rainfall remains high.
Pacaya (Guatemala): INSIVUMEH reports weak strombolian activity.
Fuego (Guatemala): A slight increase of activity has occurred over the past dayss. The INSIVUMEH volcano observatory reported 11 strombolian explosions during the past 24 hrs interval with plumes rising up to about 600 m above the crater, and incandescent fragments ejected to 100 m above the crater, creating avalanches on the upper flanks.
Two lava flows remain active towards the Taniluya and Ceniza drainages on the southern slopes, with 300 and 400 m length, respectively.
Nevado del Ruiz (Colombia): Since the last update, the volcano has been relatively calm with only internal unrest in the form of fluctuating seismic activity. Manizales observatory reports a slight increase during the past week, with earthquakes clustered in the usual location (presumably an area of magma storage) about 3.5 km NE of the Arenas crater at depths between 4-7 km.