crater lake temperature has risen about 20C since mid-April. Photo /
Ruapehu's risk of eruption may have increased, but GNS volcanologists
say nearby residents should not feel concerned.
today announced the mountain's crater lake temperature had doubled in
the past few weeks, rising from 25C to between 45C and 46C over the
past couple of days.
volcanologist Geoff Kilgour says scientists made two visits to
Ruapehu yesterday, one flight to measure the gas output and other to
sample the crater lake water and make additional ground-based gas
gas measurements indicate an increase in the amount of both carbon
dioxide (CO2) and sulphur dioxide (SO2) output ... Seismic activity
at Mt Ruapehu is usually dominated by volcanic tremor. Since the
volcanic earthquakes in late April the seismicity has been dominated
by volcanic tremor at varying levels. The level of tremor has
increased but is not exceptional in terms of the last few years.
Ruapehu crater lake in 2013. Photo / Geonet
got nothing to do with weather. And White Island, they're [volcanoes]
all independent of each other."
Scott says the activity is caused by molten lava getting trapped
inside the volcano itself.
that new pulsar heat and hot rock comes into the volcano it's whether
or not it can flow through the volcano and get out of it and if the
holes in the volcano aren't big enough to let the gas through it just
over pressurises and pops."
for those in surrounding towns worried that a lahar will swamp them,
Mr Scott says debris is unlikely to travel more than a few kilometres
from the volcano itself.
of the biggest eruptions, in 1995, only a few blots got past the 3km
or 4km mark and that was really rare. Being away from the volcano is
very safe and even the standard places you can go. Different story if
you go and climb the thing and you're camping at the crater lake or
for where it travels, Mr Scott says the majority head out towards the
Desert Rd but there have been some eruptions producing lahar on the
you're at the ski lodges, they're safe as. Ruapehu only affects
within about 3km of the lake and the nearest part of the ski fields
are about 4km or 5km away so it does make it a fairly safe
environment and the rest, once off you're off the bottom of the
volcano, nothing can touch you."
Scott says Ruapehu Alpine Lifts has shifted all of its infrastructure
- ski tows, towers, cafes - out of the valleys in case it did head in
for how the volcanic unrest occurs? "That's the $64,000 science
question of volcanologists all over the world."
Department of Conservation also issued a warning to climbers and
trampers on the mountain, to not enter the Summit Hazard Zone on Mt
Ruapehu until further notice.
Summit Hazard Zone is the area within 2km of the centre of the crater
encompasses all the peaks in the summit area, with Te Heuheu Peak at
the north end of the summit area at the edge of the zone, and the
upper Turoa skifield at the south.
and trekkers should refer to the Summit Hazard Zone map or use their
map and GPS reading skills, to determine when they are approaching
recommend climbers, trampers and walkers do not enter the zone,"
said Paul Carr, DoC's operations manager for Tongariro.
companies should also heed the advice and not take people into the
ski areas, other facilities or roads on Ruapehu or elsewhere in
Tongariro National Park - including the Tongariro Alpine Crossing -
are affected by this warning
The view of White Island from the crater floor after an eruption on April 27. Photo / GNS Science"
10 May, 2016
Last month's eruption at
White Island likely would have killed anyone standing close to the
floor of its Crater Lake, scientists say.
Fortunately, the eruption
happened late at night and no one was on the island when a surge of
ash was thrown across the crater floor late on April 27.
In a blog post, GNS
Science volcanologist Brad Scott said the steam and gas driven
eruption from the offshore volcano created a new crater, caused
landslides and excavated some of the lake.
Much of the crater floor
was covered with a green-tinged ash - but Mr Scott and his colleagues
have been able to confirm that none of the material contained magma
from deep within the active volcano, which rises 1.6km from the ocean
floor off the coast of Bay of Plenty.