Volcanologists have eye on the sky

Volcanologists from Massey University and the University of Hamburg in Germany will soon be able to record every explosive burst out of Mt Ruapehu in rain or shine, day or night, with a new high-speed Doppler Radar system.

It is the first of its kind in New Zealand and makes Ruapehu one of only a handful of volcanoes around the world watched around the clock by a radar "eye". Last week GNS Science upgraded the aviation alert to yellow following a sustained rise in the temperature of the crater lake.