Volcanos

Roundup of Global Volcanic Activity

Ruapehu (North Island): After reaching record-low temperatures in August, the volcano's closely-monitored crater lake has started to heat up very quickly since 2 September, Geonet reported. Ruapehu's crater lake displays temperatures that follow periodic cooling and heating cycles that range between about 15 and 40 °C. In mid August, a record-low of 12 °C was measured, but New Zealand scientists have detected a rapid increase in temperature over the past days, along with increased seismic activity inside the volcano. The highest-ever temperature of the lake, since it had reformed in 1999-2000 was 46°C on 11 May 2016. This peak was also accompanied by volcanic tremor and an increase in gas emissions. GNS Science back then raised the alert level to Level 2, but lowered it back to Level 1 in early July, when degassing and seismic activity became less. The heating and cooling cycles of Ruapehu's crater lake are not completely understood, but caused by a mix of volcano and geothermal processes; a heating period usually indicates a period of higher volcanic unrest which includes a higher possibility of a new eruption to occur. For now, the alert level is not raised as the current signs of unrest are weak.

Nyiragongo (DRCongo): The activity at the volcano remains intense. The February 2016 side vent on the eastern lower terrace, which stopped in May and restarted in mid August, continues to be active, too. The now quite sizeable cinder cone built at the original fissure vent continues to contain a magma column degassing with strombolian-type explosions of fluctuating intensity and aliments changing lava flows that spread over the crater floor and occasionally cascade into the central lava lake.