Meteo(BasicWeatherTheory) Flashcards
What causes variations in altimeter setting between weather reporting points?
A. Unequal hearing of the Earth’s surface
B. Variation of terrain elevation
C. Coriolis force.
A.
Temp changes CAUSE variations in 1) air pressure and 2) density. Because the EARTH’S SURFACE is HEATED UNEVENLY, altimeter setting will be different between weather stations.
B. is wrong because altimeter setting are referenced to a standard datum, and elevation alone is not the cause of variations.
C. is incorrect because Coriolis force deflects the circulation of air masses, but does not directly cause variations in altimeter setting.
The wind at 5,000feet AGL is southwesterly while the surface wind is southerly. This difference in direction is primarily due to
A. stronger pressure gradient at higher altitudes.
B. friction between the wind and the surface.
C. stronger Coriolis force at the surface.
B.
Above 2,000 feet AGL, wind flows along isobars. Below that altitude, friction with the earth’s surface deflects the wind.
A. is wrong because the pressure gradient is not always stronger at higher altitude.
C. is wrong because winds are generally calmer at lower altitudes. As a result, Coriolis force is not as effective as friction near the surface.
Convective circulation patterns associated with sea breezes are caused by
A. warm, dense air moving inland from over the water.
B. water absorbing and radiating heat faster than the land.
C. cool, dense air moving inland from over the water.
C.
During the day, land surfaces become warmer than the adjacent water surfaces. This wars the air above the land causing the air to rise. The rising air is replaced by the inland flow of cooler, dense air located over the water. As the warm air flows over the water it cools and descends. This starts the cycle all over again. During the night, the process is reversed as the land cools off faster than the water.
A. is wrong because cool, not warm, air moves inland.
B. is incorrect because sea breezes are a result of the land, not the water, absorbing and radiating heat faster.
