Question

which sentence best explains how a positive feedback loop affects climate change?
a. as climate warms, co₂ increases because plants remove less of it.
b. as the number of plants increases, the amount of co₂ decreases.
c. high clouds have a high albedo and reflect solar energy back into space.
d. high precipitation results in increased plant growth, lowering co₂.

Explanation:

A positive feedback loop in climate change amplifies the initial change. In option A, as the climate warms (initial change), plants remove less \(CO_2\) (response), which in turn increases \(CO_2\) levels further, warming the climate more. This is a positive feedback as it reinforces the warming trend. Option B is a negative feedback (more plants lower \(CO_2\), countering a potential increase). Option C is about cloud albedo (a physical property of clouds reflecting sunlight) and not a feedback loop related to the question's context of how a loop affects climate change. Option D is also a negative feedback (high precipitation - more plants - lower \(CO_2\), countering warming).

Answer:

A. As climate warms, \(CO_2\) increases because plants remove less of it.