What effect do large bodies of water have on nearby temperatures?

• A. Areas near water are cooler because water takes longer to heat than land.
• B. Water has no effect on air temperature.
• C. Water bodies cause immediate heating of the air.
• D. Wind flows from cool to warm air away from water.

Answer: (A)

Water's high heat capacity means it can absorb a lot of heat with only a small change in temperature, so large bodies of water heat up and cool down more slowly than land. Because land warms up quickly in the sun, the air over land becomes hotter while the air over water stays cooler. This cooler air tends to move toward land during the day, creating milder, cooler conditions near coasts. At night, water releases stored heat more slowly, helping keep coastal air warmer than inland areas. So areas near large bodies of water are cooler than inland areas on hot days and warmer at night, giving coastal regions milder temperatures overall. Water clearly affects air temperature, so that choice isn’t correct. It doesn’t cause immediate heating of the air. And the usual daytime wind is from the sea toward the land (a sea breeze), not away from the water.