Which statement best describes energy distribution: tropical latitudes have a net gain and polar regions have a net loss?

• A. Tropical latitudes have a net gain; polar regions have a net loss
• B. Tropical latitudes have a net loss; polar regions have a net gain
• C. Both have a net gain
• D. Both have a net loss

Answer: (A)

The main idea is how solar energy is distributed and moved around the globe. Tropics receive a lot of solar radiation per unit area because the sun is nearly overhead there most of the year. This tends to give tropical regions a surplus of energy—they absorb more energy than they emit as longwave radiation. To keep the planet in balance, this surplus is transported toward higher latitudes by atmospheric circulation and ocean currents.

Polar regions, by contrast, get sunlight at a very oblique angle and experience long periods of darkness in winter, plus ice and snow reflect a lot of energy. Their energy input is lower and their energy loss (to space as longwave radiation) is greater on average, leading to a net deficit.

So tropical latitudes have a net gain of energy while polar regions have a net loss, driving the global pattern of poleward energy transport.