Final answer:
Volcanic eruptions release greenhouse gases and can have a short-term cooling effect on global climate.
Step-by-step explanation:
Volcanic eruptions contribute to climate change on a global scale by releasing greenhouse gases such as CO2 into the atmosphere. These gases, including carbon dioxide and sulfur dioxide, can trap heat and contribute to the greenhouse effect, warming the Earth's surface. However, volcanic eruptions can also have a cooling effect on the Earth's atmosphere. When large amounts of sulfur dioxide are emitted during an eruption, they can form sulfuric acid aerosols in the stratosphere, which reflect sunlight back into space, leading to a temporary decrease in global temperatures. This cooling effect is typically short-lived, lasting for a few years.
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