Volcanic eruptions occur when magma from Earth's interior reaches the surface. As magma rises, pressure from overlying rock decreases, gases dissolved in magma separate as bubbles, and pressure increases. When this pressure exceeds the strength of rock above magma, explosive eruption occurs.
Volcanic eruption hazards include lava flows, pyroclastic flows (superheated gas and ash moving at high speed), volcanic ash (polluting air, affecting agriculture and visibility), volcanic gases (toxic gases like sulfur dioxide), and volcanic earthquakes.
Active volcanoes concentrate on the Pacific Ring of Fire, with particularly active volcanoes in Indonesia (most active volcanoes), Philippines, Japan, New Zealand, and South America. Areas around volcanoes are continuously monitored with warning systems in place.
Living in volcanic risk areas requires paying attention to local volcano observatory warnings, preparing evacuation plans, and keeping N95 masks for volcanic ash protection.