Answer: In direct effect, the person is directly affected by the source. For example, if a volcanic eruption occurs and lava flows outward, the area surrounding the volcano - including human establishments and organisms that reside there - would be affected (DIRECTLY); however, we observe that acid rain forms after this. This is because the sulfurous gases from the eruption mix with water vapor in the atmosphere. Another indirect effect of this is actually positive - radiation reflection. When a volcano eruptions, it releases gases like sulfur dioxide. Sulfur dioxide would react with other substances and produce aerosol particles. Aerosols can have huge impacts on our climate as they reflect light. This is evident when Mount Pinatubo erupted in 1991, and as a consequent, the aerosols that were produced from its gases cooled the area for 4 years.
