NAS 125 Midterm Exam Review
For each satellite, describe what is measured?
Visible imagery can only be viewed during the day and is mostly used for cloud formation. Infrared imagery measures heat radiating off clouds and the surface of the Earth. Water vapor satellite pictures indicate how much moisture is present in the upper atmosphere .
For each satellite, describe what information can be obtained.
Visible imagery is also very useful for seeing thunderstorm clouds building. Satellite will see the developing thunderstorms in their earliest stages. Infrared imagery can also be used for identifying fog and low clouds. The fog product combines two different infrared channels to see fog and low clouds at night, which show up as dark areas on the imagery. Water vapor imagery is useful for indicating where heavy rain is possible.
Why does the Antarctic ozone hole appear in the Southern Hemisphere spring?
During the winter months in the Southern Hemisphere, polar stratospheric clouds form. These clouds contain water particles that allow chlorine and bromine compounds to form and cause ozone depletion. During the spring months, the Sun's radiation supplies the energy casing the polar stratospheric clouds to vaporize and the stratospheric ozone concentration returns to normal levels.
What is the significance of stratospheric ozone for life on Earth?
In the formation and dissociation of ozone, incoming ultraviolet (UV) radiation is absorbed.This reduces the amount of UV radiation that is potentially lethal to life from reaching Earth's surface.
Distinguish between visible and infrared satellite images in terms of the type of information about the atmosphere each provides.
Infrared satellite sensors detect infrared radiation that is continually emitted to space by theEarth-atmosphere system. Hence, infrared images can be obtained 24 hours a day. Visible satellite sensors detect sunlight reflected by the Earth-atmosphere system. Hence, visible images are possible only during daylight hours.
The latitude of highest mean annual surface temperature, the heat equator, is located about ______ degrees north of the geographical equator.
10 degrees
The creation of national weather services and the foundation of the International Meteorological Organization (today's WMO) have provided us with detailed temperature records for the past __________ years.
100 or so years
How long is a sunspot cycle?
11 years
The peak of the last major glacial advance over North America occurred about ______ years ago.
18,000-20,000
A period when the global average annual temperature trended downward was
1960s through the 1970s.
On the absolute temperature scale, the freezing point of pure water at sea level is ______ K.
273.15
By international agreement, climatic averages are computed from weather records compiled over a ______ year period. You Answered
30
Climate is defined as weather conditions at some locality averaged over a standard period of _____ years.
30
This afternoon's high temperature was 27 °F and the early morning low temperature was 7 °F. The total heating degree-days for today was
48
At an altitude of about 3.5 mi above sea level, the air pressure is approximately
500mb
The Medieval Warm Episode lasted from about ______ to ______.
950...............1250
Why does a cold, dry air mass exert a greater surface air pressure than an equally cold but more humid air mass?
A cold dry air mass has a greater density than a more humid air mass. This would mean that the humid air mass has lower air pressure. This is because the molecular weight of water is less than the molecular weight of dry air.
What is a weather front? Compare the weather conditions for a warm front to that of a cold front.
A weather front is a boundary separating two masses of air of different densities. For a cold front, it is usually violent and unstable weather conditions to form while with a warm front there could be low intensity precipitation with the precipitation having the potential to be long-lasting.
A cold dry air mass has a greater density than a more humid air mass. This would mean that the humid air mass has lower air pressure. This is because the molecular weight of water is less than the molecular weight of dry air.
An adiabatic process is a thermodynamic process in which no heat is exchanged between amass and the environment. This is approximated in the atmosphere because rapid vertical movements of large bodies of air reduce the flow of energy to or from the ascending or descending body of air. Examples of adiabatic processes occurring in the atmosphere are expansional cooling and compressional warming of air.
What is an air mass? What governs the temperature and humidity of an air mass?
An air mass is a huge volume of air with uniform temperature and humidity properties that are often indicative of where it was formed. For example, an air mass that develops over a warm ocean surface becomes warm and humid.
Describe at least three instruments that are used for collecting weather data.(what do they read?, how do they work?, etc.)
Barometer, which measures air pressure. Thermometer, which measures the temperature. Anemometer , which measures wind speed.
Two equal volumes of air have the same temperature and pressure. One contains more water vapor than the other.
Both volumes of air contain the same number of gaseous molecules.
What are clouds typically like ahead of a warm front?
Stratiform
The scientific community did not widely accept the theory of plate tectonics until
The 1960's
What are the three main types of satellite images?
The three main types of satellite images are visible, infrared, and water vapor images.
latent heating
The transfer of heat energy from one place to another as a consequence of the phase changes of water
Distinguish between weather and climate.
Weather is the state of the atmosphere at a particular place and time. Variables used to describe weather include: temperature, humidity, and cloudiness. Climate describes the weather in an area averaged over a period of time. Weather describes daily atmospheric conditions while climate looks at longer periods of time and utilizes seasonal averages of rainfall, snowfall, and temperature.
Air mass advection occurs when winds blow _________ regional isotherms.
across
Water vapor is
an invisible gas
The type of barometer that is used to measure altitude:
aneroid
Radioactive decay of an isotope of potassium is a source of ______ in the Earth's atmosphere.
argon
A(n) ______ can be used to predict the weather by keeping track of the air pressure tendency.
barometer
Typically, trends in climate are geographically non-uniform in
both magnitude and sign
As a rule, ______ skies increase the diurnal (day-to-night) temperature range.
clear
What are clouds typically like a head of a cold front
cumuliform
Rising air temperature causes the saturation mixing ratio to ______
decrease
Between the tropopause and stratopause, the air pressure ______ with increasing altitude.
decreases
If a saturated (cloudy) air parcel is heated (say by absorption of radiation), its relative humidity ______.
decreases
If the temperature of an unsaturated (clear) air parcel does not change while its mixing ratio increases, the density of the parcel ______.
decreases
Solar energy output ______ as the sunspot number decreases.
decreases
Evidence from ______ firmly established Milankovitch cycles as a cause of climatic fluctuations.
deep sea sediment-cores
At the same humidity (water vapor concentration), a cold air mass is _________ a warm air mass.
denser than
The Sun's energy output varies ______ with sunspot number.
directly
As the temperature of a saturated (cloudy) air parcel falls, its relative humidity ______.
does not change
In an isothermal temperature profile, the air temperature
does not change with altitude
Air pressure tendency is usually _____ with warm air advection in the winter.
downward
In the portion of the atmosphere where most clouds occur, the air temperature _________ with increasing altitude.
drops
The _________ adiabatic lapse rate is 9.8 Celsius degrees per 1000 m.
dry
The Bowen ratio has a greater value over a ______ surface than over a ______ surface.
dry, moist
The wind-chill equivalent temperature is ______ the actual (or ambient) air temperature when the wind speed is nearly calm.
equal to
Levels of atmospheric carbon dioxide ____________ during the growing season and ____________ in winter.
fall......rise
On a clear and calm day, the relative humidity usually ______ between sunrise and early afternoon.
falls
As a general rule, lows that track from west to east across southern Canada produce ___________ precipitation compared to lows that track along the Gulf of Mexico coast.
less
At the equator over the course of a year, the rate of cooling due to emission of infrared radiation to space is ______ the rate of warming due to absorption of solar radiation.
less than
The heat conductivity of a fresh snow cover is ______ the heat conductivity of an old snow cover.
less than
The usual world-wide range in sea-level air pressure is ______ 100 mb.
less than
Polar amplification of climate change
likely took place during the Pleistocene Ice Age, consists of an increase in the magnitude of climate change with increasing latitude, is an example of the geographical non uniformity of climate change.
The net effect of more sulfate aerosols in the troposphere:
lower air temperatures
The temperature of a sunspot is ______ the temperature of the Sun's photosphere, giving the sunspot a dark appearance.
lower than
Within the atmosphere, the lowest average air temperature occurs
mesopause
Weather radar emits pulses of __________ energy that are reflected by precipitation particles (e.g., raindrops, snowflakes).
microwave
Changes of air pressure in the horizontal are ______ they are in the vertical.
much smaller than
Most cloudiness and precipitation associated with a cold front occur as a relatively _________ band along or just ahead of where the front intersects Earth's surface.
narrow
The three most common gases in the "dry" atmosphere (excluding water vapor) are
nitrogen, oxygen, argon
Absolute zero is the temperature at which
no electromagnetic radiation is emitted.
Weather systems in the middle latitudes of the Earth generally move in the direction towards the
north
Air temperatures tend to be relatively low to the ___________ of a low pressure system.
north and west
A northeast wind blows from the __________ toward the __________.
northeast....southwest
A gas that occurs in minute concentrations in the atmosphere and yet shields living organisms from exposure to potentially lethal intensities of solar ultraviolet radiation is
ozone
So that barometer readings are accurate and representative,
the instrument may be mounted indoors
The single most important source of atmospheric pollution in the United States is (are)
the internal combustion engine in motor vehicles
In response to a temperature gradient, heat flows from where it is warmer to where it is colder. This behavior illustrates
the second law of thermodynamics
The residence time of an aerosol in the stratosphere is generally longer than its residence time in the troposphere because
there is no precipitation in the stratosphere, the stratosphere is extremely stable, little exchange of air occurs between the stratosphere and the troposphere.
The portion of the atmosphere in which the principal gases (nitrogen and oxygen) occur everywhere in the same proportions is the
troposphere, stratosphere and homosphere
Conditional stability indicates that an air layer is
unstable for saturated and stable for unsaturated air parcels.
An example of latent heating:
vaporization of ocean water followed by cloud formation
__________ fronts are associated with cloudiness and precipitation over a broad band
warm
In response to the same input of heat, which one of the following substances exhibits the smallest rise in temperature?
water
Adjusting barometer readings to sea level removes the influence of ______ on air pressure.
station elevation
Clouds that form horizontal layers are described as
stratiform
___________ usually indicate fair weather.
stratiform
Explain why the climate is hotter on the leeward side of the Rocky Mountains.
The land on the leeward side of the mountain gets far less rain which often produces a desert
On a global and annual average within the troposphere, the rate of radiational cooling __________ the rate of radiational heating.
is less than
On a global scale, the most important mechanism whereby the excess heat at the Earth's surface is transported to the troposphere is
latent heating
An increase in the magnitude of a temperature change with increasing ______ is known as polar amplification.
latitude
Weather radar utilizes the _________ effect to monitor the motion of precipitation particles.
Doppler
What is the type of weather that usually accompanies a high anticyclone and a low cyclone in middle latitudes?
Fair weather usually accompanies a high cyclone and cloudy, snow, rain weather usually accompanies a cyclone
Aerosol is the name given to
solid and liquid particles small enough to be suspended in air.
Clouds located at different altitudes __________ move in the same direction indicating __________ in the horizontal wind direction with altitude.
sometimes...no change
Earth is closest to the sun
January(periphelon)
earth is farthest from the sun
July(aphelion)
- Distinguish between sensible heating and latent heating of the atmosphere. Which is more important on a global annual average basis?
Latent heat transfer associated with evaporation is the most important cooling process atEarth's surface on a global annual average. It is more important than radiational cooling and sensible heat transfer.
How does local air pressure change as a cyclone approaches your location.
Local air pressure falls
How does the local air pressure change as an anticyclone approaches your location?
Local air pressure rises as an anticyclone approaches a particular location.
The chief source of Earth's early atmosphere was out-gassing. Explain what is meant by out-gassing. Does out-gassing still operate today?
Outgassing refers to the release of gases (e.g., water vapor, nitrogen) to the atmosphere that accompanies a volcanic eruption or meteor impact on Earth's surface. Outgassing was one of the major processes involved in the evolution of Earth's atmosphere. While outgassing occurred at a rapid pace within a million years of the planet's formation, a small amount of outgassing still takes place today.
What are Milankovitch cycles? What role might they play in our understanding of climate change?
Regular variations in the precession and tilt of Earth's rotational axis and the eccentricity of its orbit around the Sun. The amount of tilt and precession and how eccentric the orbit is can cause great changes to the climate.
The Kelvin scale has no negative values. Explain why
The Kelvin scale is the best representation of average kinetic molecular energy. When a substance has a temperature of 0 K it is at "absolute zero" and essentially has no kinetic energy because all molecular motion has ceased. A substance cannot have negative kinetic energy.
Describe the Maunder minimum and its possible connection to the climate of the Little Ice Age
The Maunder minimum is referred to as a period of greatly reduced solar activity. The possible connection to the climate of the Little Ice Age is that without these sunspots, there was a cold episode in Europe.
A climatic episode favoring the thinning and retreat of existing glaciers is
The Medieval Warm Period
The state of the atmosphere averaged for all latitudes and seasons is known as
standard atmosphere
Explain what is meant by the term global radiative equilibrium.
The balance between net incoming solar radiation and infrared radiation emitted to space by the Earth-atmosphere system
sensible heating
Transport of heat from one location or object to another via conduction, convection, or both
Why are there two adiabatic lapse rates (dry rate and wet rate)
Whether or not the air is saturated with water vapor
Apply Wien's displacement law in comparing the radiational properties of the Sun versus those of the Earth-atmosphere system.
Wien's displacement law states that with increasing absolute temperature, the wavelength of the maximum radiation emitted or absorbed will decrease. Therefore, hot objects such as the Sun emit radiation that peaks at shorter wavelengths than relatively cool objects such as Earth.
Rising parcels of unsaturated air cool at a _________ rate than rising parcels of saturated (cloudy) air.
faster
As compared to the climate that prevailed through most of geological time, the climate of the past two million years has
favored the development of continental-scale glacial ice sheets.
A horizontal wind is named for the direction ___________ the wind blows.
from which
If the surface air pressure is the same everywhere, but a mass of cold air is situated next to a mass of warm air, the pressure at high altitudes is
greater in warm air
At sea level, the pressure of the atmosphere is
greatest
The proportions of the principal gases (nitrogen and oxygen) change with altitude in the
heterosphere
Within the thermosphere, the temperature is ______ and heat energy is ______.
high....low
A geostationary satellite orbits Earth at a _________ altitude than a polar-orbiting satellite.
higher
The National Weather Service Cooperative Observer Network collects weather data primarily for __________ purposes.
hydrologic, agricultural, and climatic
A temperature inversion is characterized by a(n) ______ of air temperature with altitude.
increase
The saturation vapor pressure ______ with rising air temperature.
increases
Sensible heating includes transfer of heat via __________.
phase changes of water
An example of a secondary air pollutant is
photochemical smog
Today, the principal source of atmospheric oxygen is
photosynthesis
Which one of the following heat transfer processes can take place in a vacuum?
radiation
All other factors being equal, an overcast sky _________ the day's maximum temperature. Correct Answer
raises
Ten calories of heat are added to two grams of liquid water. The temperature of the water
rise by 5 degrees Celsius
