What causes a volcanic eruption?

A volcanic eruption occurs when pressure from molten rock, or magma, beneath the Earth’s surface becomes too great for the surrounding rock to contain. This causes the magma to rise through cracks in the Earth’s crust, resulting in an eruption. Volcanic eruptions can release lava, ash, and gases into the atmosphere. The type of eruption depends on the composition of the magma, with more fluid magma causing gentle eruptions, while thick, gas-rich magma leads to explosive eruptions. Eruptions also release ash and gases that can affect global climate patterns.