The heat budget of the earth

More longwave absorption can reduce outgoing energy and create warming tendency. Exam tip: connect longwave trapping with warming forcing.

Heat budget considers the balance between incoming solar radiation and outgoing terrestrial radiation. The surface absorbs solar energy and emits longwave radiation, while the atmosphere also absorbs energy and reradiates it both upward and downward. Therefore, the budget belongs to the combined Earth-atmosphere system, not to the surface alone. Option C is incorrect because a substantial part of solar radiation reaches the surface as well. Exam tip: remember absorption, emission, and reradiation for both the surface and the atmosphere.

Part of energy is reflected and part goes into latent heat. Exam tip: connect temperature with net absorbed sensible heat.

A warmer surface can emit more energy and reduce surplus. Exam tip: treat emission response as a stabilising factor.

Water vapour is a greenhouse component and its amount can rise with warming. Exam tip: connect it with feedback process.

Radiation balance affects temperature but is not itself temperature. Exam tip: keep cause and condition separate.

Slope aspect changes the intensity of incoming solar radiation. Exam tip: connect aspect with local insolation.

Regional surpluses and deficits exist within global equality. Exam tip: understand balance and circulation together.

The direct answer is A: maximum daytime temperature occurs later because the surface continues gaining more energy than it loses for some time after maximum insolation. Insolation means incoming solar energy. Around noon, incoming energy is greatest, but the ground and lower air do not become hottest instantly. First, sunlight supplies energy to the surface. The surface stores and transfers this energy, so for a while energy gain remains greater than energy loss. Temperature therefore keeps rising even after incoming sunlight begins to decrease. Later, outgoing terrestrial radiation and other heat losses become greater than incoming energy, and the temperature starts falling. This delay is called thermal lag. Option A correctly describes the energy balance. Option B is wrong because the Sun is not born after noon; the Sun only appears to move across the sky. Option C is wrong because Earth continuously emits longwave radiation. Option D is wrong because clouds may affect radiation, but they do not stop time. Memory cue: maximum heating and maximum temperature are separated by a temperature lag.

The direct answer is A: high heat capacity and mixing of water. Diurnal temperature range means the difference between the temperature of a place during the day and at night. Water has a much higher heat capacity than land, so it needs more energy to become warm and gives up stored heat slowly. Waves and mixing spread heat through a larger water volume. Step by step: sunlight heats the sea during the day; the sea absorbs much energy without a rapid temperature rise; at night it releases heat gradually; therefore nearby coastal air does not cool or warm sharply, and the daily range remains small. Option A is correct. Option B is wrong because sand does not have one-hundred-percent albedo, and high albedo would reflect sunlight rather than explain the main maritime effect. Option C is wrong because coastal regions do have an atmosphere. Option D is wrong because the Sun’s temperature is not lower over coasts. Memory cue: land heats and cools quickly; water heats and cools slowly, so coasts have moderate temperatures.

Conduction is contact based while convection can carry heat on a larger scale. Exam tip: distinguish conduction and convection.

Heat budget considers all major energy exchanges. Exam tip: treat heat budget as integrated energy balance.

Cloud forcing depends on type and altitude. Exam tip: include cloud type in heat budget analysis.

Different surfaces can behave differently in longwave emission. Exam tip: connect emissivity with outgoing radiation.

Latitude is important but not the only control. Exam tip: use a latitude plus local factors approach.

The net result can be understood only by considering opposite effects together. Exam tip: remember competing controls.

Night temperature mainly depends on outgoing longwave and downward longwave. Exam tip: write night energy balance.

The atmosphere plays an active role in many energy processes. Exam tip: treat atmosphere as an active energy medium.

Atmospheric absorption creates a difference between surface emission and space emission. Exam tip: understand top of atmosphere balance.

Oceans store large amounts of heat and slow changes. Exam tip: connect thermal inertia with ocean heat storage.

Temperature response is not immediate because of heat storage. Exam tip: remember ocean heat storage and lag.

Surface energy balance has many incoming and outgoing components. Exam tip: see the complete surface energy budget.

Positive top of atmosphere balance indicates energy storage in the Earth system. Exam tip: understand it as system energy gain.

Heat budget numbers give a simple model of average condition. Exam tip: treat diagram values as an average model.

Heat budget is an integrated energy account of many processes and feedbacks. Exam tip: write an integrated system answer.