As arctic temperatures rise, summer sea ice and glacial melt accelerates; lighter color surfaces are thereby replaced with darker-colored surfaces leading to more absorption and surface heating. This is an example of feedback.

Positive feedback

Explanation:

Positive feedback climate is usually defined as the process where there occur changes in the region where the lighter colored surfaces such as the region of glaciers, ice caps are replaced by the dark-colored surfaces, and this results in the decreasing of the albedo (light-reflecting property) and also increase in earth's surface temperature. This type of feedback is also known as the ice-albedo feedback.

High rate of heating results in the decreasing amount of glaciers and ice-caps, thereby leading to the global warming effect.

Thus, the above-given condition is an example of positive feedback.

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