Forest fires can affect the Earth’s climate in several ways. They release greenhouse gases. They send soot and other aerosol particles into the atmosphere. And they change how the Earth’s surface reflects sunlight, especially in areas where snow falls.
Mark Flanner, assistant professor of atmospheric science, says that whether the ultimate effect is warming or cooling varies, as does how long these impacts last. The greenhouse gases are very long-lived, on the order of a century, while the smoke effects are short-lived, lasting roughly a week.