Mt Ruapehu tremors highest seen in nine years

Volcanic tremor levels at Mt Ruapehu increased over the past week and are now among the highest seen in nine years. The Crater Lake temperature has continued to rise, and GeoNet yesterday said the lake was at 36 degree celsius. It remains in a state of unrest at alert level two - a higher risk of an eruption. GNS science volcanologist Geoff Kilgour spoke to Susie Ferguson.