Why does deforestation alter local climate and rainfall patterns?

Why does deforestation alter local climate and rainfall patterns?

• A. Increased evapotranspiration and rainfall
• B. No effect on climate
• C. It always causes desertification within days
• D. Reduced evapotranspiration and altered albedo can reduce rainfall

Answer: (D)

Deforestation changes how the land handles energy and water, which shifts the local climate and rainfall. Trees contribute a lot of moisture to the air through evapotranspiration—water pulled up from soil and released from leaves as vapor. This adds humidity and supports cloud formation and rain nearby. When forests are cleared, this moisture source shrinks, so there’s less atmospheric water to form rain, often leading to drier conditions and reduced local rainfall. At the same time, removing the canopy alters the surface’s energy balance. Forests tend to absorb sunlight differently than bare ground; clearing usually increases the surface albedo (reflectivity), and the exposed soil or grasses warm up more. This warming changes the air temperature gradients and convection patterns that drive rainfall, further contributing to changes in local rainfall amounts. So the key idea is that less evapotranspiration and the altered energy balance from changed albedo can reduce rainfall locally. The other statements don’t fit this mechanism: evapotranspiration doesn’t increase with deforestation, climate change effects aren’t absent, and desertification doesn’t occur within days as a guaranteed outcome.

Deforestation changes how the land handles energy and water, which shifts the local climate and rainfall. Trees contribute a lot of moisture to the air through evapotranspiration—water pulled up from soil and released from leaves as vapor. This adds humidity and supports cloud formation and rain nearby. When forests are cleared, this moisture source shrinks, so there’s less atmospheric water to form rain, often leading to drier conditions and reduced local rainfall.

At the same time, removing the canopy alters the surface’s energy balance. Forests tend to absorb sunlight differently than bare ground; clearing usually increases the surface albedo (reflectivity), and the exposed soil or grasses warm up more. This warming changes the air temperature gradients and convection patterns that drive rainfall, further contributing to changes in local rainfall amounts.

So the key idea is that less evapotranspiration and the altered energy balance from changed albedo can reduce rainfall locally. The other statements don’t fit this mechanism: evapotranspiration doesn’t increase with deforestation, climate change effects aren’t absent, and desertification doesn’t occur within days as a guaranteed outcome.