Ash was emitted in two recent eruptions on Whakaari/White Island, an observation flight has confirmed.

There were two distinct eruptions at the active marine volcano on Thursday, based on webcam observations.

Earth Sciences New Zealand duty volcanologist Yannik Behr said the volcanic alert level remained at level 3 and aviation colour code remained orange.

Behr said after last week’s observations of “weak eruptions”, MetService had detected volcanic ash in satellite imagery since Sunday.

Sulphur dioxide was also detected by satellite imagery on Thursday and Sunday.

“The observation flight confirmed the ash plume was rising to 400–500m above sea level and was blown to the southeast for 5-8km."

Behr said ashfall from the observed activity was unlikely to impact the mainland.

A plume at Whakaari/White Island captured at 12.30pm on Thursday by a live monitoring camera at Whakatāne. Image / Earth Sciences NZ

Whakaari is 48km off the coast of Whakatāne, in the Eastern Bay of Plenty.

“As a result of the continued minor ashfall on the island, deposits of fine ash have accumulated on the main crater floor,” Behr said.

Earth Sciences NZ reported vent temperatures were about 250C and had increased since the activity started.

Temperatures were still well below the maximum of around 500C observed earlier this year.

The volcanic alert would remain at level 3 while the Earth Sciences NZ Volcano Monitoring Group continues monitoring Whakaari for any changes in activity.

The alert system is a scale from zero to six, with level 3 indicating a minor volcanic eruption.

There were currently no sensors installed on the island, and scientists relied on remote cameras, satellite data, periodic observation and gas measurement flights to track any developments, Behr said.

Its last previous eruption activity was observed on August 28, coating the island in a thin covering of ash. The activity settled quickly.

Last week’s eruptions came amid an ongoing inquest into the deadly eruption on December 9, 2019, which killed 22 people.