Volcanic activity worldwide 2 Aug 2016: Bromo volcano, Rinjani, Nevados de Chillán

Rinjani (Lombok): The volcano has remained calm since yesterday's sudden and very violent explosion.
The attached picture by Rindi Rmaniar on Instagram taken from a few kilometers distance only shows the power of the vulcanian-type explosion: it generated an eruption column several kilometers high, sent ballistic projectiles and pyroclastic flows by collapsing parts of the ash column covering all the slopes of the Baru Jari cone which grew significantly last year.
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The exact nature of the eruption remains unclear: it could be a phreatic event driven by trapped, overheated groundwater inside the cone's solidly plugged conduit that suddenly flashed into steam; or it could be the result of accumulated over-pressure caused by gasses that slowly formed bubbles (and pressurized the rock) inside the cooling lava erupted last year, or even a new batch of fresh magma that rose towards the surface and likely interacted violently with water (phreatomagmatic explosion).

Bromo (East Java, Indonesia): Low-level, but more or less continuous ash emissions continue with fluctuating intensity. A dilute plume of ash can be seen drifting NW from the volcano on yesterday's satellite images.

Nevados de Chillán (Central Chile): The activity at the volcano has again increased. While degassing and weak, sporadic ash emissions have become more frequent again since mid July, a more intense phase of activity took place yesterday: starting around 17:10 local time, the volcano erupted a dense plume of ash from the crater that rose several hundreds of meters to 3500-3600 m altitude and quickly dispersed. Ash fall occurred near the summit.
The activity lasted only a few minutes, but was the strongest since the volcano's activity in May this year.
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In its report from 15 July, SERNAGEOMIN mentions scientists had detected an increased of SO2 emissions and earthquakes associated with internal fluid movements and concluded that the hydrothermal system of the volcano was disrupted and prone to produce explosive events. The renewed increase of activity recently shows they were right in their prediction.