Discuss the mechanisms and important details of surface-atmosphere radiation exchange
What will be an ideal response?
Answer: Longwave radiation: The atmosphere absorbs most of the longwave radiation emitted by Earth's surface. This increases the temperature of the atmosphere, which causes it to radiate more energy outward. The energy radiated by the atmosphere is transferred in all directions, including downward, and so the surface receives a considerable portion of this radiation. This causes surface heating. Conduction: As radiant energy is absorbed by a solid Earth surface during the middle of the day, a temperature gradient (a rate of change of temperature over distance) develops in the upper few centimeters of the ground. In other words, temperatures near the surface become greater than those a few centimeters below. As a result, conduction transfers energy downward. At night the reverse process occurs; the topmost portion of the ground cools by the loss of longwave radiation and becomes colder than the underlying volume. Energy is then conducted upward. Convection: Convection is a process whereby heat is transferred by the bodily movement of a fluid—that is, a liquid or gas. In contrast to conduction, convection involves the actual displacement of molecules. Unlike conduction, which transfers energy from the surface to the atmosphere, convection circulates this heat between the very lowest and the remaining portions of the atmosphere. The direction of heat transfer is upward when the surface temperature exceeds the air temperature (the normal situation in the middle of the day). At night the surface typically cools more rapidly than the air, and energy is transferred downward. Convection can be generated by two processes in fluids: local heating (free convection) and mechanical stirring (forced convection).
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The location on Earth's surface, directly above the focus, is called the
A) tsunami. B) seismic center. C) epicenter. D) surface focus.
The type of weather system known as a “mid-latitude cyclone” cannot form over the tropical
ocean because:a. surface temperature contrasts are not large. b. the ocean surface has a lot of waves. c. the Coriolis force is weak in the tropics. d. both (a) and (b) e. both (a) and (c)
Absorption is the assimilation of radiation and its conversion from one form to another
Indicate whether the statement is true or false
You go camping in Canada with a friend. You both go to bed when the Sun goes down and get up when the Sun comes up, but you both notice that you are not getting enough sleep! What time of year are you most likely near?
A) fall (autumnal) equinox B) summer solstice C) spring (vernal) equinox D) winter solstice