Volcanic ash can also stops the sunlight from going in and out from the earth. Decreases in the earth's temperatures are observed after large volcanic eruptions. Some examples are the eruptions of Mount Agung in Bali that erupted in 1963, El Chichon (Mexico, 1983), Ruiz (Colombia, 1985), and Mount Pinatubo (Philippines, 1991). Even for large eruptions, the ash clouds do not stay for a long time.