How do climate and weather differ, and what roles do the atmosphere and oceans play in Earth's energy balance?

• A. The atmosphere has no role in energy balance; only oceans do.
• B. Weather is the long-term average; climate is the short-term atmospheric state.
• C. Weather is the short-term state of the atmosphere; climate is the long-term averages; the atmosphere traps infrared radiation, and oceans store heat and redistribute it via currents.
• D. Climate is determined solely by solar output.

Answer: (C)

Weather is the day-to-day state of the atmosphere—temperature, humidity, clouds, winds. Climate is the long-term pattern of those conditions, described by averages and typical ranges over many years. The atmosphere and oceans both shape Earth’s energy balance. The atmosphere traps infrared radiation that would otherwise escape to space, a greenhouse-type effect that helps keep surface temperatures warmer. The oceans store vast amounts of heat because of their high heat capacity and move it around the globe through currents, redistributing energy between regions and seasons. This heat storage and transport by the oceans smooth short-term fluctuations and drive longer-term climate influences, while atmospheric processes set how much solar energy is absorbed and how much infrared energy is retained. So the best description is that weather is the short-term atmospheric state, climate is the long-term averages, the atmosphere traps infrared radiation, and oceans store heat and redistribute it via currents.