Scientists in Vanuatu have kept the eruption hazard warning at level one for the Ambae volcano but caution last week's explosions were unusually powerful.
A Geohazards Technical Director, Sylvain Todman, says three large blasts a week ago have provided data that can now be used to more closely predict further eruptions.
He says the frequency and power of volcanic activity have not changed dramatically in the days since then.
"What's happened the last time is it's the first time we witness a very strong explosion like this and we didn't have so much experience about precursors as the first signal from this kind of activity so now we could take this event and we could follow up this same kind of signal that we witnessed the last time."
Sylvain Todman warns people need to be prepared as the situation could change very quickly.
He says ash has affected crops and some water supplies.