What is a volcano?
A volcano is an opening on the surface of a planet or moon that allows material warmer than its surroundings to escape from its interior. When this material escapes, it causes an eruption. Volcanoes can be active, dormant, or extinct depending on the last time they erupted.
How do we know volcanoes effect the climate?
In 1883, Mount Krakatoa erupted in the Indian Ocean. Because i the telegraph lines connecting the world, scientists were able to track the dust cloud. They noticed that the following year the temperature fell by 2 degrees and there was record amounts of rain in some parts of the USA. Artists noticed that the dust caused amazing sun sets.
Once they realised what the eruption had caused they looked at the times other volcanoes had erupted. They realised that, a bigger eruption of Mount Tambora in 1815 had caused a 'year without a summer' in 1816 when crops failed causing famine.
How do volcanoes aff the climate?
when a volcano erupts, there will be a lot of rain and lightning around the volcano because the dust and ash attract water droplets. This can cause floods in the area close to the volcano. If the eruption is powerful the ash and dust can go into the jet stream high in the atmosphere and be carried around the whole world. Scientists think that big dust particles let the sun in but don't let heat out causing the world to warm up and if the dust particles are small they block heat from the sun causing the Earth to cool.
We know what volcanoes can do but we will never be able to control them.