Mt St Helens

• siesmometer:

  • used for measuring ground movements/earthquakes
  • when the ground movement increases in frequency it is a sign a volcano is about to erupt
• sulphur dioxide detector:

  • detects sulphur dioxide in the air around the volcano
• thermal imaging cameras:

  • picks up an image that detects the temperature of the inside of a volcano.
• volcanic bombs:

  • if you see it is a sign that a volcano is about to erupt (balls of magma)