Volcanic eruptions

Question 1

There are signs warning of an eruption before most volcanic eruptions
Volcanologists (scientists who studied volcanoes) monitor changes using

Answer 1

GPS, tilt meters, satellites, seismometers and gas detection

Question 2

Signs of an eruption include:

Answer 2

Magma rising which can be detected by heat sensors and satellites

Changes in surface level as rising magma causes bulges

Increased emissions of sulphur dioxide and other gases

Increased seismic activity caused by magma movement detected by seismometers