In Popocatepetl / Mexico, the activity is characterized by exhalations of water vapor, gas and ash - 34 on December 15, 147 on December 16 - and nocturnal incandescence, more intense at the time of exhalations.
Various explosions took place; on December 15th, at 12:37, 13:23, 13:51 and 18:57; on December 16, at 3:04 and 6:37, the latter accompanied by a ash plume of 2,500 meters, dispersing to the northeast.
The seismicity is marked by earthquakes VT of M 1,5 and 1,8 and tremor of low amplitude during 39 minutes.
Volcanic alert level remains at Amarillo fase 2.
Sources: Cenapred and Webcams from Mexico.
An increase in Peteroa's activity is reported for December 16th. The seismicity is characterized by tremor impulses, associated with a greyish pulsatile degassing of a height less than 800 meters, containing particulate material.
The eruptive plume disperses to the southeast toward Argentina.
Incandescence is observed, as well as a series of thermal anomalies of low intensity on the active zone.
Sources: Sernageomin & Volcanes de Chile
In Vanuatu, the fissural eruption, located near the cone of the 2015 eruption in the Ambrym Caldera, continued into the day of 16 December.
The lava fountains formed a curtain some 100 meters long over the crack, reaching a height of 40 meters, and feeding a lava flow towards the eastern part of the caldera. (John Tasso / Volcanodiscovery)
The VMGD report of 16:23 reports explosions and continuous emissions of ashes that mark several craters: Marum, Benvow and Niri mbwelesu. Ash falls are reported all day on the villages.
Volcanic earthquakes that accompany activity cause cracks in buildings and soil, especially in southeastern areas of the island; it is advisable to stay clear of thecracks, not to bury them, or to throw things in them.
At the latest news, the team Trail by fire, on site, reports on December 16 in the evening, the stop of the fissure eruption and the drainage of existing lava lakes.
A descending ALOS-2 interferogram provides information on displacements of more than one meter, presumably due to the deep magma intrusion that feeds the eruption (Tara Shreve / Twitter)
Sources: VMGD, Trailbyfire, Simon Carn, Thomas Boyer.
Ambrym Caldeira - plumes of the eruption site and the lava lakes - VMGD webcams - one click to enlarge
Ambrym - hot spots on this image Sentinel-2 image bands 12,11,4 of 15.12.2018 - one click to enlarge
Ambrym - Interferogram descending ALOS-2 between 03.11 and 15.12.2018, with displacements of more than one meter, presumably due to the deep magma intrusion that feeds the eruption (Tara Shreve / Twitter)
At Merapi, on the island of Java, an avalanche of lava is reported on December 16 at 7:08 pm EST; it remained confined in the upper 300 meters of the volcano, above Kali Gendol.

It is recommended to the surrounding communities to remain calm and informed, the situation not endangering the inhabitants of the slopes and surroundings ... for now
Sources: BPPTKG
At Soputan / Sulawesi, the eruption continues on December 17, with ash plumes ranging in height from 1,500 to 7,000 meters, and nighttime glow.
Note that the airport of Manado remains operational.
Sources: BNPB, Magma Indonesia & GSCF