Term
| what volcanoes are made of |
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Definition
| volcanoes spewed out the same gases then as they do today: mostly water vapor (about 80 percent), carbon dioxide (about 10 percent), and up to a few percent nitrogen. These gases (mostly water vapor and carbon dioxide) probably created the earth's second atmosphere. |
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Term
| the earth's first atmosphere |
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Definition
| The earth's first atmosphere (some 4.6 billion years ago) was most likely hydrogen and helium - the two most abundant gases found in the universe - as well as hydrogen compounds, such as methane and ammonia. Most scientists feel that this early atmosphere escaped into space from the earth's hot surface. |
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Term
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Definition
| As millions of years passed, the constant outpouring of gases from the hot interior |
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Term
| outgassing supplied ____which formed___ and then rain led to the formation of _____, and large amount of ____ became locked in the _____ and the atmosphere became rich in _____ |
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Definition
water vapor...
clouds...
large bodies of water (lakes, river, oceans)...
Co2...
sedimentary rocks...
nitrogen |
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Term
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Definition
| A small, rising parcel of warm air produced when the earth's surface is heated unevenly. |
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Term
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Definition
| Energy propagated in the form of electromagnetic waves. These waves do not need molecules to propagate them, and in a vacuum they travel at nearly 300,000 km per sec (186,000 mi per sec). |
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Term
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Definition
| waves that release energy when they are absorbed by an object. Because these waves have magnetic and electrical properties. they do not need molecules to propagate them. In a vacuum, they travel at a constant speed of nearly 300,000 km (186,000 mi) per second - the speed of light. |
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Term
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Definition
| (abbreviated µm), which is equal to one-millionth of a meter (m); thus, 1 micrometer (µm) 0.000001 m 10-6 m. |
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Term
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Definition
| discrete packets of energy |
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Term
| wavelengths of radiation depend primarily on |
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Definition
| the objects temperature...The higher the object's temperature, the shorter are the wavelengths of emitted radiation. By the same token, as an object's temperature increases, its peak emission of radiation shifts toward shorter wavelengths |
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Term
| relationship between temperature and wavelength |
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Definition
| Wien's law (or Wien's displacement law) after the German physicist Wilhelm Wien, (pronounced Ween, 1864 - 1928), who discovered it. |
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Term
| the sun emits maximum amount of rays around.. |
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Definition
| 0.5 µm. Since our eyes are sensitive to radiation between 0.4 and 0.7 µm, these waves reach the eye and stimulate the sensation of color. This portion of the spectrum is therefore referred to as the visible region, and the radiant energy that reaches our eye is called visible light. |
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Term
| shortest & longest wavelengths |
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Definition
| The color violet is the shortest wavelength of visible light. Wavelengths shorter than violet (0.4 µm) are ultraviolet (UV). The longest wavelengths of visible light correspond to the color red. Wavelengths longer than red (0.7 µm) are called infrared (IR). |
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Term
| (relative to the sun) the cool earth emits all of its energy |
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Definition
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Term
| sun radiating energy vs earth radiating energy |
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Definition
| Since the sun radiates the majority of its energy at much shorter wavelengths than does the earth, solar radiation is often called shortwave radiation, whereas the earth's radiation is referred to as longwave (or terrestrial) radiation. |
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Term
| why dont all objects get progressively colder if they always radiating energy? |
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Definition
| If the earth and all things on it are continually radiating energy, why doesn't everything get progressively colder? The answer is that all objects not only radiate energy, they absorb it as well. If an object radiates more energy than it absorbs, it becomes colder; if it absorbs more energy than it emits, it becomes warmer. |
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Term
| what effects the rate that something radiates and absorbs energy? |
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Definition
| The rate at which something radiates and absorbs energy depends strongly on its surface characteristics, such as color, texture, and moisture, as well as temperature. For example, a black object in direct sunlight is a good absorber of solar radiation. It converts energy from the sun into internal energy, and its temperature ordinarily increases. |
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Term
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Definition
| Any object that is a perfect absorber (that is, absorbs all the radiation that strikes it) and a perfect emitter (emits the maximum radiation possible at its given temperature) is called this.they do not have to be colored black, they simply must absorb and emit all possible radiation. Since the earth's surface and the sun absorb and radiate with nearly 100 percent efficiency for their respective temperatures, they both behave as this |
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Term
| the average temperature at which a radiative equilibrium is achieved= radiative equilibrium temperature |
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Definition
| If we assume that there is no other method of transferring heat, then, when the rate of absorption of solar radiation equals the rate of emission of infrared earth radiation, a state of radiative equilibrium is achieved. |
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Term
| why is there such a large difference between the radiative equilibrium temperature and earth's observed average surface temperature? |
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Definition
| the earth's atmosphere absorbs and emits infrared radiation. Unlike the earth, the atmosphere does not behave like a blackbody, as it absorbs some wavelengths of radiation and is transparent to others. |
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Term
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Definition
Objects that selectively absorb and emit radiation, such as gases in our atmosphere
and
Substances such as water vapor, carbon dioxide, clouds, and snow that absorb radiation only at particular wavelengths. |
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Term
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Definition
| it actually becomes less dense than the air directly above it. The warmer air rises and the cooler air sinks, setting up thermals, or free convection cells, that transfer heat upward and distribute it through a deeper layer of air. |
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Term
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Definition
| At the top of the atmosphere, solar energy received on a surface perpendicular to the sun's rays appears to remain fairly constant at nearly two calories on each square centimeter each minute or 1367 W/m2 - a value called the solar constant. |
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Term
| scattered or diffused light |
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Definition
| Moreover, when sunlight strikes very small objects, such as air molecules and dust particles, the light itself is deflected in all directions - forward, sideways, and backwards. The distribution of light in this manner is called scattering. |
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Term
| why we see blue skys, white suns, and have red sunsets |
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Definition
| Because air molecules are much smaller than the wavelengths of visible light, they are more effective scatterers of the shorter (blue) wavelengths than the longer (red) wavelengths. Hence, when we look away from the direct beam of sunlight, blue light strikes our eyes from all directions, turning the daytime sky blue. At midday, all the wavelengths of visible light from the sun strike our eyes, and the sun is perceived as white. At sunrise and sunset, when the white beam of sunlight must pass through a thick portion of the atmosphere, scattering by air molecules removes the blue light, leaving the longer wavelengths of red, orange, and yellow to pass on through, creating the image of a ruddy or yellowish sun |
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Term
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Definition
| the percent of radiation returning from a given surface compared to the amount of radiation initially striking that surface. and it represents the reflectivity of the surface. |
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Term
| snow burns/ snow blindness |
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Definition
| When solar energy strikes a surface covered with snow, up to 95 percent of the sunlight may be reflected. Most of this energy is in the visible and ultraviolet wavelengths. Consequently, reflected radiation, coupled with direct sunlight, can produce severe sunburns on the exposed skin of unwary snow skiers, and unprotected eyes can suffer the agony of snow blindness. |
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Term
| earth and waters average albedo |
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Definition
| Water surfaces, on the other hand, reflect only a small amount of solar energy. For an entire day, a smooth water surface will have an average albedo of about 10 percent. Averaged for an entire year, the earth and its atmosphere (including its clouds), will redirect about 30 percent of the sun's incoming radiation back to space, which gives the earth and its atmosphere a combined albedo of 30 percent |
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Term
| how do the earth and the atmosphere maintain a yearly energy balance |
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Definition
| the earth's overall average equilibrium temperature changes only slightly from one year to the next. This fact indicates that, each year, the earth and its atmosphere combined must send off into space just as much energy as they receive from the sun. The same type of energy balance must exist between the earth's surface and the atmosphere. That is, each year, the earth's surface must return to the atmosphere the same amount of energy that it absorbs. If this did not occur, the earth's average surface temperature would change |
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Term
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Definition
| The transfer of heat by molecular activity from one substance to another, or through a substance. Transfer is always from warmer to colder regions. |
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Term
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Definition
| Motions in a fluid that result in the transport and mixing of the fluid's properties. In meteorology, convection usually refers to atmospheric motions that are predominantly vertical, such as rising air currents due to surface heating. The rising of heated surface air and the sinking of cooler air aloft is often called free convection. (Compare with forced convection.) |
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Term
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Definition
| The warming of an atmosphere by its absorbing and emitting infrared radiation while allowing shortwave radiation to pass on through. The gases mainly responsible for the earth's atmospheric greenhouse effect are water vapor and carbon dioxide. |
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Term
| At which temperature would the earth be radiating energy at the greatest rate or intensity |
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Definition
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Term
| Sunlight that bounces off a surface is said to be ____ from the surface. |
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Definition
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Term
| The albedo of the earth's surface is only about 4%, yet the combined albedo of the earth and the atmosphere is about 30%. Which set of conditions below best explains why this is so? |
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Definition
| high albedo of clouds, low albedo of water |
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Term
1. less sunlight is transmitted through the cloud
2.more sunlight is reflected from the cloud
3.less sunlight is absorbed by the cloud-
4.more light is scattered by the cloud |
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Definition
| On the average, as a cloud grows thicker (taller), which below does not occur |
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