Increased Volcanic Activity at Four Locations

Volcanic unrest at New Zealand's White Island is increasing, GNS volcanologist Brad Scott confirmed during a recent visit of the island on 21 Jan.
Mr Scott’s observations confirmed that hydrothermal activity in the small 'hot lake' has increased. The most common activity is "doming-up" of the lake surface by steam/gas, bringing large amounts of sediment to the surface, often with vivid white steam/gas 'flashing' from around the base. Every so often stronger events happened. This activity has been increasing since late 2012 and is now semi-continuous.
The elevated activity corresponds to the increased tremor signal recently visible.
GNS volcanologist Brad Scott said “the hydrothermal activity is some of the most vigorous I have seen at White Island for many years. This type of activity usually leads to stronger volcanic activity and is a significant concern.”

The lava dome that was first observed in late November has not changed since the last observations on 1 January 2013.
Seismicity continues to show elevated levels of volcanic tremor and this is likely to be generated by the processes driving the vigorous hydrothermal activity in the lake.
The state of unrest at White Island is increasing and future eruptions are possible with little or no warning. The increased level of unrest does mean that there is a hazard to visitors. Past activity indicates that eruptions, such as that which occurred on 5 August 2012, could occur with little or no warning, even when the Alert Level is 1 (volcanic unrest). Caution should be exercised when visiting the island.
GNS Science continues to closely monitor White Island through the GeoNet project.

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Tongariro volcano (New Zealand): unrest and volcanic gas emissions continue, alert level unchanged
Source: Volcano Discovery - 1/22/12, By T

Tongariro's current status remains characterized by strong degassing from the Te Maari craters, the site of eruptions in August and November 2012. At present, seismic activity is low. This activity is likely to go on several years, but Tongariro could produce new eruptions with little or no precursors, New Zealand's GNS writes in its recent update:
The Te Maari craters at Mount Tongariro continue to be active with continuous emissions of steam and volcanic gas. Emission of a steam and gas plume has been a continuous feature of the mountain since the August 2012 eruption. The gas is coming from a large fumarole and crack in a cliff just east of the Upper Te Maari crater. The main Upper Te Maari crater is also discharging gas but at a lesser rate. Fumaroles associated with a fissure farther to the east have declined and are no longer easily visible.

Volcanic gas from the plume may continue to be smelt in areas downwind of the volcano. GNS Science volcanologists will be making gas measurements at the next available opportunity to compare to those made at the end of December 2012, however recent visual observations show that the emissions are on-going and sustained. Observers of the mountain may notice that emissions appear to be stronger on some days than others, which is due to a combination of variability in the degassing rate and atmospheric conditions which make the plume more visible on some days. GNS head volcanologist Gill Jolly said “gas and steam emissions from the volcano will continue to be a feature of the mountain for several years to come.”

Aerial observations at the end of 2012 showed that a large amount of material had in-filled the Upper Te Maari crater as part of the 21 November 2012 eruption, however the main shape of the crater had not changed.

Seismicity has remained relatively low with no earthquakes yet recorded beneath the mountain in 2013.

The Volcano Alert Level remains at 1 and the Aviation Colour Code remains at Yellow.
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