Correct Response: A. Deforestation significantly reduces the sequestration of carbon dioxide, a potent greenhouse gas. With less forest to sequester carbon dioxide, the concentration of carbon dioxide in the atmosphere increases, warming the atmosphere. A warmer atmosphere warms the oceans, causing the volume of water to increase. This and the melting of land-based glaciers from a warmer atmosphere raise sea level. Algal blooms triggered by coastal runoff (B) increase carbon sequestration and so would have little effect on sea-level rise. Similarly, volcanic eruptions in the tropics (C) typically cool the atmosphere and consequently cool the oceans, reducing glacial melt and decreasing the rate of sea-level rise. An increase in wind-blown dust from desertification (D) typically reduces the temperature of the troposphere, which would also not lead to a rise in sea level.
