AP BIOLOGY

Detailed explanation-1: -This is called “sequestration.” When forests are cut down, much of that stored carbon is released into the atmosphere again as carbon dioxide (CO2). This is how deforestation and forest degradation contribute to global warming.

Detailed explanation-2: -When fossil fuels are burned, they release large amounts of carbon dioxide, a greenhouse gas, into the air. Greenhouse gases trap heat in our atmosphere, causing global warming.

Detailed explanation-3: -Trees and other plants absorb carbon dioxide from the atmosphere as they grow. This is converted into carbon and stored in the plant’s branches, leaves, trunks, roots and in the soil. When forests are cleared or burnt, stored carbon is released into the atmosphere, mainly as carbon dioxide.

Detailed explanation-4: -Without carbon dioxide, Earth’s natural greenhouse effect would be too weak to keep the average global surface temperature above freezing. By adding more carbon dioxide to the atmosphere, people are supercharging the natural greenhouse effect, causing global temperature to rise.

Detailed explanation-5: -At a global scale, forests help maintain Earth’s carbon balance. Over the past four decades, forests have moderated climate change by absorbing about one-quarter of the carbon emitted by human activities such as the burning of fossil fuels and the changing of land uses.