Explain how the volcanic ash from the krakatau eruption cause global temperatures to decrease

Every time a volcano would erupt it then would throw a large volume of sulfur dioxide as well as water vapor, ashes and dust into the atmosphere. The large amount of the ashes and gases then can bring climatic patterns by increasing then the planetary reflectivity that would cause the cooling of the atmosphere or decreasing of the global temperature.

Earths place in space 

Magma is outside the volcano  and lava is inside the volcano.