Which of the following causes adiabatic temperature changes in atmosphere?
- A.Deflection and advection
- B.Latent heat of condensation
- C.Expansion and compression of the air
- D.Partial absorption of solar radiation by the atmosphere
Correct answer
Explanation
The correct answer is C, Expansion and compression of the air. Adiabatic temperature changes in the atmosphere are caused by the expansion and compression of air, with no heat added or removed.
When a parcel of air rises, the pressure around it falls, so it expands. The work done in expanding uses up its internal energy and the air cools, even though no heat leaves it. When air sinks it is compressed and warms in the same way. Dry air cools at about 10 degrees Celsius per kilometre of ascent, the dry adiabatic lapse rate. Saturated air cools more slowly, about 5 to 6 degrees per kilometre, because condensation releases latent heat.
A is wrong because deflection and advection move air horizontally and are not the adiabatic process. B is wrong because latent heat of condensation only slows the adiabatic cooling of saturated air; it is not its cause. D is wrong because absorbing radiation adds heat from outside, the opposite of an adiabatic change.
Exam tip: Rising air expands and cools, sinking air is compressed and warms: dry rate about 10 °C/km.
Practice Questions
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- A.20%
- B.40%
- C.50%
- D.60%
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- B.pollution
- C.cloudiness
- D.the inclination of the Earth about its axis
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- A.The Baltic Sea
- B.The Black Sea
- C.The Caspian Sea
- D.The Norwegian Sea
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- A.Lima
- B.Buenos Aires
- C.Montevideo
- D.Santiago
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- A.Oil ports
- B.Naval ports
- C.Packet stations or ferry ports
- D.Inland ports
Show answer
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