Shared Flashcard Set

Details

AOSS 102 REVIEW Q's - CHAPTERS 1-3
Review assignments
88
Meteorology
Undergraduate 4
10/06/2011

Additional Meteorology Flashcards

 


 

Cards

Term
On the basis of temperature, list the layers of the atmosphere from the lowest layer to the highest. Which layer is the coldest? The warmest? Which layer contains all of our weather?
Definition
Troposphere, stratosphere, mesosphere, thermosphere
Coldest = top of the mesosphere
Warmest = top of thermosphere
Weather = troposphere
Term
What is the average (standard) temperature lapse rate in the troposphere?
Definition
6.5 degrees Celsius per each 1000 meters
Term
Explain the concept of air pressure in terms of mass of air above some level.
Definition
The pressure at any level in the atmosphere may be measured in terms of the total mass of the air above any point.
Term
Why does air pressure always decrease with increasing height above the surface?
Definition
Near sea level, atmospheric pressure decreases rapidly as air density is greatest, whereas at high levels it decreases more slowly.
Term
What causes the wind to blow?
Definition
if there is a gradient in pressure in the horizontal.
Term
Does a north wind blow from the north toward the south, or from the south toward the north?
Definition
Wind direction is expressed in the direction from which the wind blows. So a north wind blows from the north to the south
Term
Define relative humidity
Definition
The relative humidity is the ratio of the amount of water vapor actually in the air to the maximum amount of water vapor required for saturation at that particular temperature
(and pressure).
Term
Define dew point
Definition
The temperature to which air would have to be cooled for saturation to occur ; a measure of the amount of water vapor in the air
Term
If the air temperature is close to the dew point, would the relative humidity be high or low? Explain.
Definition
At the dew point air will be saturated. The closer temperature is to the dew point the closer it is to saturation - thus the relative humidity would be high
Term
The most abundant greenhouse gas in the earth's atmosphere
Definition
water vapor
Term
The most abundant gases in the earth's atmosphere by volume are
Definition
nitrogen and oxygen
Term
The gas that absorbs most of the harmful ultraviolet radiation in the stratosphere
Definition
ozone
Term
What is the difference between weather and climate?
Definition
The difference between weather and climate is a measure of time. Weather is what conditions of the atmosphere are over a short period of time, and climate is how the atmosphere "behaves" over relatively long periods of time.
Term
A temperature of 27°C would be equal to what temperature on the Kelvin scale?
Definition
K = C + 273
K = 27 + 273
K = 300
Term
A change of one degree on the Celsius scale is _ _ _ _ _ _ _ _ a change of one degree on the Fahrenheit scale.
Definition
larger than

an increase in temperature of 1˚C equals an increase of 1.8˚F
Term
This provides a measure of the average speed of air molecules
Definition
temperature
Term
A planet whose atmosphere is mainly nitrogen and oxygen
Definition
Earth
Term
In the stratosphere, the air temperature normally
Definition
increases with increasing height
Term
According to the Gas Law, what is the relationship between pressure density?
Definition
Pressure is proportional to density times temperature
Term
The order of the layers of the atmosphere from lowest to highest is
Definition
Troposphere, Stratosphere, Mesosphere, Thermosphere
Term
If two air parcels at sea level have the same size but different temperatures, the colder parcel of air will have ______ pressure, but _______ density than the warm parcel
Definition
the same pressure but higher density than the warm parcel
Term
The earth's first atmosphere was composed primarily of
Definition
hydrogen and helium
Term
The temperature of the tropopause
Definition
is much colder than the temperature at the earth's surface
Term
Warming in the stratosphere is mainly caused by
Definition
absorption of ultraviolet radiation by ozone
Term
The outpouring of gases from the earth's hot interior is called
Definition
outgassing
Term
The primary source of oxygen for the earth's atmosphere during the past half billion years or so appears to be
Definition
photosynthesis
Term
Much of Tibet lies at altitudes over 18,000 feet where the pressure is about 500 mb. At such altitudes, the Tibetans are above roughly _____ of the air molecules in the atmosphere
Definition
50% of the air molecules in the atmosphere
Term
The ozone hole is found in this atmospheric layer
Definition
stratosphere
Term
In the atmosphere, how does advection differ from convection?
Definition
Advection is horizontal transport, while convection is vertical transport
Term
How does the temperature of an object influence the radiation it emits?
Definition
According to the Stefan-Boltzmann Law the amount of radiation an object emits is proportional to its temperature (in Kelvin) raised to the fourth power.
Term
How does the amount of radiation emitted by the earth differ from that emitted by the sun?
Definition
The Sun's surface has a temperature of about 6000°K while the Earth is near 300°K. If we raise each to the fourth power and compare we will find that the Sun emits about 160,000 times more energy that the Earth
Term
How do the wavelengths of most of the radiation emitted by the sun differ from those emitted by the surface of the earth?
Definition
According to Wein's Law the wavelength of maxiumum emission is inversely proportional to the temperature (in Kelvin). The Sun, being about 6,000°K, emits its maximum energy at 0.5 µm while the Earth, being around 300°K, emits its maximum around 10 µm
Term
What are the most abundant selectively absorbing greenhouse gases in the earth’s atmosphere?
Definition
The most abundant is water vapor, though it is variable. The second most abundant is carbon dioxide.
Term
Explain how the earth and its atmosphere balance incoming energy with outgoing energy.
Definition
Incoming solar radiation is absorbed, warming the ground. The warm ground emits longwave (infrared) radiation, much of which is absorbed inn the atmosphere, warming the atmosphere. The warm atmosphere radiates both out to space to balance the incoming solar radiation and back to the ground.
Term
What are the main factors that determine seasonal temperature variations?
Definition
Seasonal temperatures are regulated by the amount of solar energy received at the earth’s surface, which is determined primarily by two things: the angle at which the sunlight strikes the earth's surface, and how long the sun shines on any latitude (daylight hours)
Term
In the Northern Hemisphere, why are summers warmer than winters even though the earth is actually closer to the sun in January?
Definition
Because the difference in orbit is relatively minor compared to the greater variation over the year in solar elevation angle.
Term
If it is winter and January in New York City, what is the season and month in Sydney, Australia?
Definition
It's still January, but it's summertime.
Term
In the middle latitudes of the Northern Hemisphere, explain why even though the earth’s surface receives maximum sunlight on June 21 (summer solstice) the warmest time of year typically occurs in July.
Definition
At the time of the summer solstice the amount of solar energy available is greater than the loss of longwave radiation. Only after the ground heats more and hence increases longwave radiation and the solar radiation is diminished by a diminishing elevation angle in late July is the incoming equal to outgoing and temperatures stop rising.
Term
A heat transfer process in the atmosphere that depends upon the movement of air is:
Definition
convection
Term
What helps to explain why even though northern latitudes experience 24 hours of sunlight on June 22, they are not warmer than latitudes further south?
Definition
solar energy is spread over a larger area in northern latitudes, some of the sun's energy is reflected by snow and ice in the northern latitudes, increased cloud cover reflects solar energy in the northern latitudes, and solar energy is used to melt frozen soil in the northern latitudes
Term
This is released as sensible heat during the formation of clouds
Definition
latent heat
Term
Where are the days and nights of equal length all year long?
Definition
at the Equator
Term
The earth's radiation is often referred to as ____ radiation, while the sun's radiation is often referred to as ____ radiation.
Definition
longwave, shortwave
Term
Which latitude would experience the fewest hours of daylight on Dec. 22? 60S, 20S, 0, 20N, 60N
Definition
60N
Term
The combined albedo of the earth and the atmosphere is approximately:
Definition
.3 or 30%
Term
Which of the following is an incorrect association?
albedo - percent of radiation reflected from a surface
kinetic energy - energy of motion
black body - selective absorber
long-wave radiation - earth radiation
Definition
black body - selective absorber
Term
Which of the following has the highest albedo?
snow, sand, water, grass
Definition
snow
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?
Definition
high albedo of clouds, low albedo of water
Term
The horizontal transport of any atmospheric property by the wind is called:
Definition
advection
Term
Clouds ____ infrared radiation and ____ visible radiation.
Definition
absorb, reflect
Term
On the average, about what percentage of the solar energy that strikes the outer atmosphere eventually reaches the earth's surface?
Definition
50%
Term
Most of the radiation emitted by a human body is in the form of
Definition
infrared radiation and is invisible
Term
The sun emits a maximum amount of radiation at wavelengths near ____, while the earth emits maximum radiation near wavelengths of ____.
Definition
0.5 micrometers, 10 micrometers
Term
One micrometer is a unit of length equal to:
Definition
one millionth of a meter
Term
The proper order from shortest to longest wavelength is
Definition
ultraviolet, visible, infrared
Term
If the absolute temperature of an object doubles, the maximum energy emitted goes up by a factor of
Definition
16
Term
The latitude at which there is a yearly balance between incoming and outgoing radiation is about
Definition
37degrees
Term
If the earth's average surface temperature were to increase, the amount of radiation emitted from the earth's surface would ____ and the wavelength of peak emission would shift toward ____ wavelengths.
Definition
increase, shorter
Term
The sun emits its greatest intensity of radiation in:
Definition
the visible portion of the spectrum
Term
Which greenhouse gas absorbs both in the infrared and ultraviolet region?
Definition
ozone
Term
The sun is directly overhead at Mexico City (latitude 19°N):
Definition
twice a year
Term
On a calm, sunny day, why is the air next to the ground normally much warmer than the air just above?
Definition
Under calm conditions there is less mixing so the heating that happens at the surface is transferred to the atmophere via conduction, which is an inefficient process compared to physical mixing by wind
Term
Explain why the warmest time of the day is usually in the afternoon, even though the sun’s rays are most direct at noon.
Definition
At noon the energy being received from the Sun is still greater than what the ground is emitting as longwave radiation. Hence there is an energy surplus and temperatures will rise until later in the day when incoming and outgoing radiation are equal.
Term
Explain how radiational cooling at night produces a radiation temperature inversion.
Definition
The ground will cool fastest due to longwave radiation. Conduction is an inefficient process so the cold is first transmitted to the air nearest the surface and which cools the layer above it. Hence the coldest air will be that in contact with the ground.
Term
Explain why the daily range of temperature is normally greater in dry regions than in humid regions and on clear days than on cloudy days.
Definition
Humidity, haze, and clouds prevent sun’s energy from reaching surface; thus, lower daytime temperatures; and at night, moist air absorbs infrared radiation, emits it back to surface, thereby keeping nighttime temps higher. so there is little fluctuation in the temperature, therefore a lower daily temp range

clouds will lower daytime temps by reflecting incoming solar radiation, while they will also keep nighttime temps higher by absorbing earth's outgoing infrared radiation, then emitting it back to the surface - thereby retarding the cooling process
Term
Why is the hottest region of the world in the subtropical deserts of the Northern Hemisphere and not at the equator?
Definition
At the equator the air tends to be more humid so more energy goes into evaporation. Also, at the equator there tend to be more clouds that will reflect sunlight from the surface.
Term
What does relative humidity represent?
Definition
The ratio of the amount of moisture in the air to the amount the air COULD hold at that temperature.
Term
When the relative humidity is given, why is it also important to know the air temperature?
Definition
To know how much moisture is available for precipitation we need to know the temperature to know how much the air could hold.
Term
Explain two ways the relative humidity may be changed.
Definition
change air temperature (which in turn changes water vapor capacity) OR change the amount of water vapor in the air
Term
When outside air is brought indoors on an extremely cold winter day, the relative humidity of the heated air inside oft en drops below 10 percent. Explain why this situation occurs.
Definition
At low temperatures the air can hold little moisture. When that air enters the house in the winter it is warmed to the house temperature but no extra moisture is added so the relative humidity will be much lower than outside.
Term
In summer, humid regions typically have ____ daily temperature ranges and ____ maximum temperatures than drier regions.
Definition
smaller, lower
Term
An important reason for the large daily temperature range over deserts is
Definition
there is little water vapor in the air to absorb and re-radiate infrared radiation
Term
If the temperature is 25°C and the relative humidity is 50% approximately what is the actual vapor pressure?
Definition
15 mb
Term
Over the earth as a whole, one would expect to observe the smallest variation in temperature from day to day and from month to month at ____
Definition
on a small island near the equator
Term
If the temperature is 20°C and the actual vapor pressure, e, is 10 mb what is the relative humidity?
Definition
about 0.45
Term
If the temperature is 35°C what is the saturation vapor pressure?
Definition
about 53 mb
Term
The lowest temperature that can be attained by evaporating water into the air is known as the
Definition
wet-bulb temperature
Term
At 40°F, the atmosphere is saturated with water vapor. If the air temperature increases to 60°F, with no addition or removal of water vapor, one may conclude that the dew point is about:
Definition
40°F
Term
As the air temperature increases, with no addition of water vapor to the air, the dew point will:
Definition
remain the same
Term
The temperature to which air must be cooled in order to become saturated is the
Definition
dew point temperature
Term
Suppose saturated polar air has an air temperature and dew point of -10°C, and unsaturated desert air has an air temperature of 35°C and a dew point of 10°C. The desert air contains ____ water vapor and has a ____ relative humidity than the polar air
Definition
more, lower
Term
If the air temperature increased, with no addition or removal of water vapor, the actual vapor pressure would
Definition
stay the same
Term
What are the reasons why water warms and cools much more slowly than land?
Definition
solar energy penetrates more deeply into water
heat energy is mixed in a deeper layer of water
water has a higher heat capacity`
a portion of the solar energy that strikes water is used to evaporate it
Term
If very cold air is brought indoors and warmed with no change in its moisture content, the saturation vapor pressure of this air will ____ and the relative humidity of this air will ____.
Definition
increase, decrease
Term
The percentage of water vapor present in the air compared to that required for saturation is the:
Definition
relative humidity
Term
At what time of day is the relative humidity normally at a minimum?
Definition
when the air temperature is highest
Term
If the air temperature remains constant, evaporating water into the air will ____ the dew point and ____ the relative humidity.
Definition
increase, increase
Term
If the air temperature in a room is 70°F, the saturation vapor pressure is 25 mb, the dew point temperature is 45°F, and the actual vapor pressure is 10 mb, then the relative humidity must be near ____ percent.
Definition
40
Supporting users have an ad free experience!