Composition of
the atmosphere (15 pts). The five most abundant
gases in the atmosphere (listed here in alphabetical order): argon
(Ar), carbon dioxide (CO2),
nitrogen (N2), oxygen (O2), and water vapor (H2O) (you should know approximate concentrations of
all but CO2
and be able to list them in order from most to least
abundant). Water vapor (H2O)
and carbon dioxide (CO2) are
greenhouse gases. What does the greenhouse effect do? What
weather variable is commonly used to measure atmospheric water
vapor content? Typical values of that variable in
Tucson during the year.
Atmospheric
evolution (10 pts). About how old is the
earth? What was the earth's first atmosphere composed of?
Where is our present atmosphere thought to have come from? What
are the three most abundant gases emitted by volcanoes? What
important atmospheric constituent in our present atmosphere did
not come from volcanoes? What is the principal source of that
gas? Why were stromatolites, cyanobacteria, and
the banded iron formation mentioned in class?
Air pollution (0 pts). Air
Quality Index (AQI). A pollutant is considered unhealthy when the
AQI exceeds what value?
Carbon monoxide
(CO) (10 pts). Toxic, colorless, odorless.
Produced during incomplete combustion (what would complete
combustion produce). Oxygenated fuels and catalytic
converters. Early morning wintertime pollutant. What is a
surface inversion layer, when do they form? Stable and unstable
atmospheric conditions. Would a surface inversion layer act
to concentrate or disperse CO? CO is a serious (potentially
deadly) indoor hazard. Scattering of
Light (0 pts). Water droplets and ice crystals in clouds,
microscopic particles, and air molecules all scatter
("splatter") light. Are we able to see sunlight being
scattered by air?
Tropospheric
ozone and Stratospheric Ozone (O3) (10 pts). Ozone aggravates existing
respiratory diseases, is harmful to plant life, and damages
materials such as rubber. Ozone is a secondary pollutant and is a
key component of photochemical smog (also known as Los
Angeles-type smog). To produce smog, ozone reacts with
hydrocarbons. The gaseous product of that reaction condenses and
forms a smog cloud that we can see. Peak ozone and
photochemical smog concentrations occur on summer afternoons. Ozone
layer.
What beneficial role does it play? Natural formation
of stratospheric ozone. The chlorine in
chlorofluorocarbons (CFCs) destroys stratospheric ozone.
Sulfur dioxide (SO2) (10 pts).Toxic and aggravates
existing respiratory diseases. The first pollutant that people
were aware of. Natural and man made sources. Involved in
some of the world's worst air pollution disasters such as the
Great London Smog of 1952. The word smog was first used to
describe the combination of sulfurous smoke + fog; the term
London-type smog is now used. SO2
reacts in clouds to form acid rain. The pH scale. What
gas was used in the acid rain demonstration in class?
Particulate Matter (PM) (5 pts).
Small particles (generally less than 10 micrometers across) that
are inhaled into the lungs and sometimes even enter the
bloodstream. Sources of PM. PM is a year round
pollutant, a health concern, and also affects visibility.
How are PM and gaseous pollutants most effectively removed
from the atmosphere?
Mass, weight,
density, and pressure (15 pts). Mass is
the amount of a particular substance. On the earth gravity pulls
downward on a mass producing weight. Pressure at any level in the
atmosphere is determined by the weight of the air above (this is a
large scale way of thinking about and understanding
pressure). Pressure is defined as force
(weight) divided by area and acts like a force (a force that
pushes upward, downward, and sideways). Common pressure units and
typical sea level pressure values.
Pressure and density decrease with increasing altitude (you should
be able to explain why). How does the rate at which pressure
decreases with increasing altitude depend on air density?
Sample questions ( from the online example
quizzes )
Practice
Quiz: 15, EC2, EC3 Quiz
#1: 3, 17a,b Final Exam: 6,
11
_________________________ This semester's Practice
Quiz covered all of the material
above
Newer material covered following the Practice Quiz is shown
below _________________________
Layers of the atmosphere
(20 pts). Troposphere: lowest layer in the
atmosphere, decreasing temperature with increasing
altitude (why is the warmest air found near the
ground), contains most of the water vapor, clouds
and weather, can be stable or unstable (strong up
& down air motions possible).
Stratosphere: there's an isothermal layer and then
a layer where temperature increases with
increasing altitude (a temperature inversion),
what causes air to warm in the stratosphere,
stable layer, contains the ozone layer.
Approximate altitudes of these layers.
Units: meters, kilometers, feet, miles.
Sample questions Practice
Quiz: #8, 16b
Quiz #1: 4, 17
Final Exam: 19
Ideal Gas Law (5 pts). This is a microscopic explanation of air
pressure. Two equations (which will be
provided in class during the quiz)
P = N k T / V & P
= ρ
R T
N is the number of air molecules in a volume V, T is temperature
and ρ is
density. R and k are both constants. You
should be able to determine what will happen to the pressure in a
rigid container or something flexible like a balloon if you change
one or more of the variables in the equations above. What
variables could you change together in such a way that the
pressure would stay constant? Volumes of atmospheric air
obey Charles' Law, what is Charles' Law? In the
atmosphere why is warm air normally low density air and cold air
normally high density air? Sample
questions
Quiz #1: 16 Final Exam: 22
Vertical
forces acting on air parcels (15 pts).
Two forces, one points upward, the other downward. The
strength of one of the forces depends on the air inside the
parcel, the other on the air outside the parcel. These two forces
are usually in balance (they point in opposite directions and
cancel each other out). What happens to the balance when you warm
or cool a parcel of air (the strength of which of the two forces
changes)? Basically you should be able to explain why a
balloon of hot low density air rises and a balloon of cold high
density air sinks.
Archimedes principle states than an object
immersed in a fluid (this can be a liquid like water or a gas
like air) experiences an upward buoyant force that is equal to
the weight of the fluid displaced by the object.
Basically objects that are less dense than the fluid around
them float, objects that are denser sink. What causes
the upward buoyant force (see Quiz #1 Question #13 in the list
of sample questions below).
Sample questions
Quiz #1: 13, 14 Station model notation (20 pts).
How and where are the following weather variables plotted on a
surface map: cloud cover, temperature, dew point temperature, wind
direction and speed, common weather symbols (rain, snow, fog, rain
shower, thunderstorm, tropical storm and hurricane),
pressure. Units. After pressure is measured,
what important adjustment is made before the pressure is plotted
on the surface map? Why is that necessary? Average and typical
range of sea-level pressure values. Universal
time (UT), Greenwich Meridian time (GMT), Zulu time (Z). Sample
questions
Practice Quiz: 14, 19?
Quiz #1:
10 Final Exam: 52
Surface
weather maps (25 pts).Isobars and isotherms (one of
each is shown in the figure below). Small horizontal
differences in pressure cause the wind to blow. Air
motions around high and low pressure centers (northern
hemisphere). Does the figure below show a center
of high or low pressure? Would you expect
the air at Pt. A to be warmer or colder than at Pt. B?
Convergence and divergence. Rising air motions,
what can cause air to rise and why is rising air
important? Sinking air. Strong and weak pressure
gradients and their effects. Sample questions Practice
Quiz: 2, 10, 11 Quiz #1: 7, 8, 9
Quiz #2: 3
Final Exam: 7, 10a&d, 34
Fronts (15 pts). You
should be able to identify cold and warm front symbols used on
surface maps. In each of the cases below you should be able
to say whether the air at Pt. A is warmer or colder than at Pt.
B. What direction are the two fronts below moving?
Which of the fronts below would cause rising air motions (why is
rising air important)?
Sample Questions
Quiz #1: 11 Final Exam: 21 (cP means a cold dry
air mass), 47
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