Ash and sulphur darken the world
The most insidious threats from volcanoes are ash and sulphur, which cause massive harm to climate, environment, and communities. And the more severe the eruption, the more ash and sulphur are produced.
An ash cloud rises and spreads with the wind.
The ash blocks out the light, grounding planes, whereas sulphur particles make the cloud cover thicker, blocking out even more sunlight.
Sulphur particles react with water molecules in the stratosphere
at altitudes of 15-25 km. The reaction produces droplets of sulphuric acid, some of which fall as acid rain, while others remain in aerosol-form.
The aerosols absorb solar energy,
reflecting the light back into space. The reduced quantity of sunlight cools Earth's surface, and in some places, average temperatures are reduced by up to 17 degrees.
Ash and major volcanic fragments bury homes and traffic.
Electricity and sewerage collapse, allowing disease to spread.
Sulphur in the atmosphere makes the rain acid,
polluting soil and water resources for 20-50 years. Ash, acid rain, and cold kill plants and animals, causing all food production to stop.
Falling temperatures spread to the oceans,
causing the sea ice to spread and ocean currents to slow. Cold, nutrient-rich bottom water no longer rises, and ocean food chains collapse.