Active Volcanoes

In the flowchart below, it explains that Active Volcanoes are volcanoes that had at least one eruption in its past 10,000. Aside from that, active volcanoes can be also classified as erupting or dormant. These erupting and dormant volcanoes are also active volcanoes but the only difference is that the erupting volcano is a volcano that is having an eruption and dormant volcano is not erupting but supposed to erupt again so don't be confused with these two, ☺

Monitoring active volcanoes

Key techniques for monitoring a volcano. Hundreds of small earthquakes are caused as magma rises up through cracks in the Earth's crust. Temperatures around the volcano rise as activity increases. Thermal imaging techniques and satellite cameras can be used to detect heat around a volcano.

Volcanologists use many different kinds of tools including instruments that detect and record earthquakes (seismometers and seimographs), instruments that measure ground deformation (EDM, Leveling, GPS, tilt), instruments that detect and measure volcanic gases (COSPEC), instruments that determine how much lava is moving underground (VLF, EM-31), video and still cameras, infrared cameras, satellite imagers, webcams, etc!