1)
A) Speaking in terms of physical elements of geography seen in this picture, we see water
leading up to a beach made of small rocks (we assume). There are a few palm trees lining the
beach and then a lush forest behind the trees. There are also large rocks. Fauna, flora,
landforms, rocks, water are all seen. Cultural Elements include the boat and hut which are
indicating that there must be some settlement and at least some population. The boat is a
form of transportation and it looks like there may even be a bridge, which is a means of
transportation as well.
B) The picture of Stockholm, Sweden shows more in the way of cultural elements of geography
then the previous picture. Here, we see cars, trucks, busses, and what looks like it may be a
boat, serving as transportation. There are bridges and roads which were man-made structures.
This is obviously a densely populated area judging from the building we see, including the
scattered high rising structures. The physical elements are limited to the body of water. There
are no trees or plants seen, climate is difficult to determine and the landscape looks flat.
C) The rocky mountain national park picture shows an array of physical elements. There are
rocks, such as the one seen up close, mountainous terrain in the way of landforms, and what
looks like dusty soil on the path the people are walking on. There are flora and fauna present,
ranging from the plant seen up close to the vast field of evergreens in the distance. The climate
looks somewhat pleasant judging by what the people are wearing but cannot be determined for
sure. There are a few cultural elements shown as well. There is some kind of a man-made
physical structure which the people are walking towards, other than that the terrain looks
unsettled. The walkers look more like visitors than people who inhabit the area.
2)
The lithosphere is the earth’s crust and broken and unconsolidated particles of mineral matter
that lie atop the bedrock. There are abundant variations as far as the variety of landforms, both
on the seafloor and on the surface of dry land.
The atmosphere is the gaseous envelope of air surrounding the earth. Most of the atmosphere
stays close to Earth’s surface and rapidly thins with increased elevation. It is kept in motion by
solar energy and the Earth’s rotation. It is the very complex mixture of gases that allows for life
to maintain.
The hydrosphere is the water in our environment, in all its forms. The ocean is the majority, but
it also includes the cryosphere –water frozen as snow and ice.
The biosphere is where life can exist. The term includes all living things known as biota.
3) Latitude and longitude are measured in degrees, minutes, and seconds, with each unit getting
successively more precise. Latitude is the distance north or south of the equator beginning at 0
degrees on the equator and moving toward 90 degrees at the North and South poles. There are
360 degrees in a circle, 60 minutes in one degree, and 60 seconds in one minute. Longitude
4)
5)
6)
7)
8)
9)
does the same thing but measures East-West. Together, latitude and longitude form a grid of
the entire earth, allowing us to easily identify where any one particular point is.
The Earth’s rotation gives rise to the daily alteration of light and darkness. This variation in
exposure to sunlight influences temperature, humidity and wind movement. If the earth didn’t
rotate we would have areas of the earth that were light all the time and areas that were
permanently dark. Revolution causes the earth to revolve around the sun, at first this seems to
have little effect on seasonal changes but when combined with inclination and polarity,
revolution and rotation do impact seasonal changes. If the earth did not revolve then we would
not get seasonal changes at all. The earth would remain rotating, with night and day, but would
never vary in distance from the earth. Inclination is the world’s tilt. If the world were not tilted,
but were instead even with the plane of the ecliptic, we would have identical temperatures
going away from the equator in each direction. The axis of Earth always points in the same
direction, without this consistency, known as parallelism, seasons would rotate entirely
different. They would still happen, but not the way we know them to occur today.
Perihelion is the point where the earth is closest to the sun, it occurs on about January 3rd at
91,455,000 miles. Aphelion is when the Earth is furthest away from the sun, occurring around
July 4th at 92,955,806 miles.
The vertical rays of the sun strike directly on the Tropic of Cancer (23.5 degrees north of the
equator) on the June Solstice. This is the day when the solar altitude would be 90 degrees. The
earth does not tilt any more than this. Conversely, the vertical rays of the sun never go below
23.5 degrees south of the equator. This is the December Solstice, where the North pole is the
furthest away from the sun.
The Arctic Circle experiences its longest day of the year on the June Solstice and we call this day
the summer solstice. The Antarctic Circle experiences it shortest day of the year and they call
this day the Winter Solstice
Seasonal changes are less noticeable because temperatures stay within a steady range at the
equator during all seasons. Away from the equator we see greater fluctuations in daylight hours
and temperature changes during the different seasons.
The day lengths are becoming shorter on this day, August 8th, in the Northern Hemisphere.
LAB EXERCISE 2 PART I
1) A) Chicago= 41 north 87 west
B) Tokyo= 35 N 139 E
C) Sydney= 34 S 151 E
D) Singapore= 1 N 103 E
E) Buenos Aires= 34S 58W
2) A) Bangkok Thailand
B) Moscow, Russia
C) Thalnepantla, Mexico
D) Nairobia, Kenya
E) Aukland, New Zealand
LAB EXERCISE 2 PART II
1) Is attached to this document!!
2) a) 35 N 130 E
b) 19 N 110 W
c) 23 S 14 E
d) 8 S 178 E
3) 40000/360=111.11 x 10 = 1111.11 kilometers, is how far North of the equator you would be at
10 degrees North latitude.
4) Simply put, the answer is because the world is round! If you are traveling along the equator,
then you are traveling at the “fattest” part of the sphere. If you begin your travels at 60 degrees
N latitude then you would be traveling a far shorter distance in order to move ten degrees of
longitude. A gridded sphere will have much smaller individual gridded units as you retreat away
from the area to measure circumference.
LAB EXERCISE 7 PART I
1) 23.5 degrees N
2) A) 66.5 degrees N
B) 66.5 degrees S
3) The Southern Hemisphere is tilted away from the sun’s energy.
4) A) Because half of the equator is in light and the other half is in darkness.
B) This is where the circle of illuminations shows the difference between night and day.
C) Yes, at the Arctic circle.
LAB EXERCISE 7 PART II
This section is attached and labeler 7:2
LAB EXERCISE 8 PART I
1) a) 22 S
b) 6 S
c) 17 N
d) 19 S
2) a) 22 S; 22 degrees; 68 degrees
b) 6 S; 44 degrees; 46 degrees
c) 17 N; 87 degrees; 3 degrees
4) March 29: 3 N;
July 3:
23N;
October 14: 8S;
87;
67;
82;
daylight
daylight
darkness
Unit 2
1. What are the four layers of the atmosphere based on temperature?
Describe the pattern of temperature change with altitude within each
layer. What is the heat source within each layer, if any? (9 points)
The Troposphere, Stratosphere, Mesosphere, and Thermosphere. The
Troposphere averages about 60 degrees (Fahrenheit) at its lowest point and
steadily decreases to an average low of about -70 degrees at its highest
point. It is heated in part because the earth’s surface absorbs solar radiation
and transfers this heat to the air. The lower Stratosphere’s temperature
remains fairly constant at about -70 degrees, but then begins to increase
sharply, reaching about 65 degree toward the top, the heat is due to
increased ozone concentration which absorbs ultraviolent radiation. The
Mesosphere cools steadily as we rise in elevation, to temperatures as cold as
-225 degrees. There is no heat source in this layer. The Thermosphere is
warmed due to various atoms and molecules absorbing ultraviolent rays from
the sun and thus splitting and heating. Temperatures steadily rise in this
layer to the extreme level of 3600 degrees. Rises is temperature in the
various layers of the atmosphere are due to the heating sources mentioned,
areas that are cold simply lack these heat sources.
2. Describe the trend in atmospheric pressure as altitude increases. What is
the reason for this trend? (3 points)
A general rule is that pressure decreases upwards at a decreasing rate.
Atmospheric pressure can be simplified as the weight of the overlying air.
The taller the column of air exerting pressure on the air bellow, the greater
the atmospheric pressure. It makes sense that at the very lowest altitude we
find the highest pressure because the lowest point would have the greatest
amount of air above it, causing the highest pressure. The reason we find
pressures decreasing at a decreasing rate going up is because most of the
mass of the atmosphere is found relatively close to ground level.
3. What is ozone? What are the differences between "good" ozone and "bad"
ozone? (5 points)
Ozone is a form of oxygen molecule consisting of 3 atoms of oxygen, rather
than the more prevalent two atoms, what we call O-2, ozone is O-3. Ozone is
created in the upper atmosphere due to ultra-violet solar radiation’s impact on O-2
molecules. Generally, we say that ozone high up is good, ozone closer to us is bad.
The ozone in the Stratosphere protects plants and animals (including us) by block
harmful rays of the sun which cause skin cancer, among other things. In the
troposphere ozone does not naturally occur at harmful levels in this area, but
human activities has caused its rising accumulation. Ozone is 0-3 either way, but
the difference is in where it accumulates.
4. What are the three most abundant gases in the atmosphere? In contrast,
how much water vapor and carbon dioxide is present in our atmosphere?
Explain why these two gases are so important to weather and climate
patterns. (4 points)
The three most abundant gases are nitrogen, oxygen, and argon. Water
vapor 0-4 percent of volume of dry air. It has a significant impact of
weather and climate because it is the source of all clouds and
precipitation. It also plays a major role in a number of heating and
cooling processes in the atmosphere. Carbon dioxide plays a significant
role in the weather and climate primarily due to its ability to absorb
infrared radiation and therefore help to warm the lower atmosphere. It
accounts for .038% of volume in the atmosphere, but that number is
considered to be on the rise my most atmospheric scientists.
5. How is weather different from climate? What are the four "basic
ingredients" of weather and climate? (3 points)
The term weather refers to short term atmospheric conditions for a given
time in a specific area. Weather is an ever-changing state, sometimes
seemingly erratic and we generalize these patterns into a composite
pattern which we call climate. Climate essentially summarizes not only
the averages but the variations and extremes. 4 basic ingredients=
temperature; moisture content; pressure; wind.
6. Describe the major factors controlling climatic variation over the Earth's
surface. (7 points)
Latitude; the continuously changing positional relationship between the
sun and the earth brings continuously changing amounts of sunlight and
radiant energy to different parts of the earth’s surface. Thus, first and
foremost the distribution of heat is a product of latitude.
Distribution of land and water; because oceans heat and cool more slowly
then do land masses, maritime areas experience milder cold periods and
milder heat periods than do landlocked areas. Ocean areas are also
typically more humid
General circulation of the oceans; ocean currents assist in heat transfers
and they assist in moving cooler water equatorward and warmer water
poleward.
Altitude; this has major implications in mountainous regions, as we rise in
elevation we see temperature, pressure and moisture generally decreasing
in the troposphere.
Topographic barriers; mountains and large hills can effect climate by
diverting wind flow.
Storms; they create specialized weather circumstances and so they are
considered a control, some storms are prominent enough to not only
effect weather, but to effect climate as well.
LAB EXERCISE 1 PART I
1) a: 13.1 b: 95.1
2) a: 7.6
b: 1.3
H: 70.4
c: 108.7 d: 44.4
c: 16.5
i: 8.3
LAB EXERCISE 1 PART II
1) 72cm= 28.4
24m= 78.7
1300km= 807.3
e: 2 f: 143.3 g: 98.6
d: 117.5 e: 5.9
f: 37.9
g: 396.9
4.5l= 4.8
144g= 5
228kg= 502.7
12degrees C= 53.6
2) 55Inches= 139.7
1774 ft= 541.1
220yds= 201.1
23900miles= 38,455.1
24qts= 22.7
300gallons= 1,135.5
26 oz= 737.1
4500lbs= 2043
88degrees F= 31.1
LAB EXERCISE 4 PART I
1) 24,000 inches or 2000 feet
2) 62500 x 4.5 = 281,250 / 63360 = 4.438 miles
3) 250000 x 4.5 / 63360 = 17.75 miles
4) 50000 x 7.5 / 100000 = 3.75 kilometers
5) 9 statues miles
13 kilometers
6) 24000 x 3 = 72000/12 = 6000 ft or 1.13 miles or 1.8 km
LAB EXERCISE 4 PART II
1) 1:31,680
2) The “0” is not always on the far left of scales on graphical scales. I could
not find why is the book, but I would wager a guess that having room
going the other way allows someone to see the distance going in the
opposite direction more easily.
3) The fractional scale of the map would still work fine. As long as both were
enlarged at the same proportion to another then it would still be to scale.
The distance between two points would change in inches but in relation to
each other in real life and in the representative section being shown on a
graphical scale would remain equal.
4) Yes they would still be usable as long as the map were made for it and
blown up/shrunken at the same rate.
LAB EXERCISE 6
Fahrenheit A=70
B=55
C= 80
D= 75
E=80
F=50
G=35
H=80
EXERCISE 6 PART II is attached and labeled EX6 PT2
Unit 3
1. Your text states that there are three areas of the electromagnetic
spectrum that are of particular importance to physical geographers.
Describe these three areas, and why they are important to physical
geography. Are these areas considered short-wave radiation or long-wave
radiation? (7points)
Visible light, ultraviolet radiation, and infrared radiation. Visible and ultraviolet radiation are considered
short-wave radiation. Infrared radiation ranges from short-wave and is part of solar radiation, to
longwave radiation emitted by the earth; terrestrial radiation. Visible light are wavelengths of light to
which the human eye is capable of responding. They are between 0.4 and .7 micrometer wavelengths.
About 47% of the total energy arriving at earth from the sun are in the form of visible light. Ultraviolet
radiation are wavelengths just shorter than the human eye can sense. The sun is the major source of
ultraviolet radiation as well, although much of this radiation is actually absorbed by the ozone layer.
Infrared radiation are wavelengths just longer than the human eye can sense. They range from on the
shorter end emitted by the sun, to on the longer end, thermal infrared, emitted by the earth.
2. Define the processes of conduction, convection, advection, and latent heat
transfer. Each of the four processes are at work in the following scenario.
Identify one example of each process from the following paragraph (be
creative!): (8 points)
It is a windy March evening. Chucky has just left the recreation center
after a particularly intense workout. He sits down on the cold concrete
steps outside the library to wait for a friend. They are going to study for
the Climate & Vegetation midterm. It's a chilly night, and Chucky can see
his breath in the night air. He shivers and wonders why his friend is taking
sooooooooo long!!!
The concrete Chucky sits on is cold due to conduction. Convection is
allowing his body heat molecules to physically move away from Chucky’s
body. The reason Chucky feels particularly cold during this windy evening
could be because of advection, the wind is causing cooler air to circulate
and hit Chucky’s skin. He can see his breath because of latent heat.
3. One of the most important phenomena in the lower atmosphere is the
greenhouse effect. Explain processes and gases involved, and why the
greenhouse effect is so important to life on Earth. Explain the difference
between the greenhouse effect and global warming? (4 points)
A number of gases in the atmosphere, including water vapor, carbon
dioxide and methane, readily transmit incoming shortwave radiation from
the sun but do not easily transmit outgoing longwave terrestrial radiation.
Shortwave solar radiation come from the sun and are absorbed into the
earth’s surface, raising the temperature. However, the Earth’s longwave
radiation is inhibited from transmitting back through the atmosphere by
the greenhouse gases. Without the greenhouse effect the average
temperature of earth would only be about 5 degrees Fahrenheit as
opposed to the current average of 59 degrees Fahrenheit. Global warming
is the result of human action. Global warming occurs because of the
significant increase in greenhouse gases, most notably carbon dioxide, due
to the burning of fossil fuels, among other things. Global warming is
causing the earth’s overall temperature to rise and is a testament to the
adverse effects humans are having on the energy balance of earth itself.
4. Define specific heat. Explain differences in specific heat between land and
water. Why do these differences have an effect on climate? Discuss three
other reasons that water bodies have more moderate climates than
landmasses. (6 points)
Specific heat is the amount of energy required to raise the temperature of
1 gram of a substance by 1 degree Celsius. The specific heat of water is 5
times greater than that of land. Meaning, water can absorb much more
solar energy without increasing its temperature. The ocean is like a great
reservoir of heat, areas inland have more extreme climates than areas
close to or completely surround by water. The oceans make for moderate
temperatures as compared to areas at similar latitudinal locations that are
further away from the ocean. Another reason is transmission; the suns
rays penetrate deep into the ocean than they do on land, therefore solar
energy is absorbed by a much greater volume of matter in water.
Mobility; because the ocean is so turbulent and is always mixing, the heat
can be dispersed more broadly and deeply. Evaporative cooling; since
moisture is unlimited on the ocean evaporation is much more prevalent
than on land. The cooling effect of evaporation slows down any heat
buildup on a water’s surface.
5. The graph below (Figure 4-25 from your text) shows mean monthly
temperatures for Dallas and San Diego.
a) Fill in the following for each city (estimate from the graph): (3
points)
Dallas
San Diego
Average Annual Temp.
____65___ ___63____
Maximum Monthly Temp
____86___ ___70____
Minimum Monthly Temp
____43___ ___58____
Temperature Range (Max____43___ ___12____
Min)
b) You'll notice that Dallas and San Diego are at roughly the same
latitude, but temperature ranges are very different. Describe the
annual temperature trend for each location, and explain why they
are so different. (3 points)
They are so different because of the distance San Diego is from the
ocean. The ocean absorbs heat in the summer, making for a more
mild average temperature, and then gives off heat during the winter
months, making for a more pleasant average winter temperature.
Both cities have similar average temperatures because they share
very similar locations as far as longitude.
c) You will also notice that the mean monthly March temperature is
the same for Dallas as in San Diego, approximately 15ºC (59ºF). It
might seem that conditions are the same in both cities for that
month. Describe temperature differences that are likely to exist
between Dallas and San Diego during March (think about day to day
differences). (2 points)
Temperature differences in March can be expected to coincide with
the general trends described previously. Dallas probably has colder
nights and hotter days during March, while San Diego follows the
trend of experiencing more mild fluctuations in temperature. Again,
this can be most directly attributed to the ocean’s effect of
moderating heat distribution; absorbing heat during the day and
releasing it at night.
6. Considering the normal lapse rate (6.5ºC / 1000m or .65ºC / 100 m), if
the temperature in Boulder, CO is 29ºC (~ 2700 meters), what would you
expect the temperature to be in Estes Park, CO (~ 4100 meters)? How
about at Bethoud Pass, CO (~ 6300 meters)? (2 points) 1.3
Estes Park=29-9.1= 19.9
Berthoud Pass= 19.9-13.5=6.4-1.3= 5.1
7. Describe how air warms and cools adiabatically. (4 points)
Air cools adiabatically due to the expansion that occurs in rising air. As air
rises and expands, the molecules spread through a greater colume of space
and this requires energy. The decrease in temperature is a result of the
molecules spreading further away from each other and therefore not colliding
as often. This is cooling by expansion and it happens anytime air rises in our
atmosphere.
When air descends it is warming adiabatically. The descent causes
compression, which causes the molecules to draw closer together and
therefore collide more frequently. The result is an increase in temperature.
8. What is an ocean gyre? Given the generally pattern of flow, what type of
ocean current (temperature and direction of flow) flows on the east side
vs. the west side of continents? (3 points)
Ocean gyres flow clockwise in the northern hemisphere and counterclockwise in the southern hemisphere due to a series of enormous elliptical
loops elongated east-west and centered approximately at 30 degrees of
latitude. The clockwise spinning ocean current on the west side of
continents causes colder water to flow from the poles toward the equator,
and on the East side of continents, in the northern hemisphere, oceanic
currents cause warmer water to be cycled upward from the equator. The
reverse is true of continents in the southern hemisphere.
EXERCISE 9 PART I + II is attached and labeled EX9 PT I + II
EXERCISE 10 PART I
1) Temperature Contrast in the Arctic Region is greatest in the Winter
2) a) One region where this is observed is in the Sahara desert.
b) The reason we see the hypothetical pattern stay constant because
of the lack of variations in precipitiation and elevation seen in this
area. Without these factors, and because this region is entirely
land locked, there are no factors that would effect the climate. Also
wind patterns are probably similar.
3) a) Cool ocean currents seem to have more of an effect in the summer.
b) These ocean currents might have more of an effect in the summer
because the ocean is able to absorb energy from the sun during hot
summers.
4) a) One area of the map that displays a large temperature change
between summer in winter is the area encompassed by greenland.
b) The change is so different due to the nature of pole regions.
Because of the tilt of the earth Northern Greenland is exposed to
almost constant sun, with the North Pole receiving sunlight around
the clock for a short period of time. In the winter, however,
Northern Greenland would experience almost no sunlight
whatsoever. With darkness occupying a majority of the day, the
suns solar energy is unable to heat this area during this time
period.
c) Areas closer to the equator will usually experience less change in
annual temperature. One example of this would be the islands just
north of Australia.
d) There is very little change in temperature because sunlight does
not vary nearly as much along these areas. Also, since the islands
are relatively small and surrounded by water the ocean will act to
help sustain a constant average temperature. It will absorb the
suns solar energy as needed and emit the energy during cooler
periods.
Unit 4
1. How do pressure gradient force, the Coriolis effect, and friction interact to determine
surface wind speeds and direction? (3 points)
Pressure gradient is the idea that if pressure is higher on one side of a parcel of air, the air
parcel will move from the area of higher pressure towards the area of lower pressure. The
Coriolis effect the direction of wind flow. In the Northern hemisphere the Coriolis effect
deflects to the right and 90 degree, and the opposite is true in the Southern hemisphere. This
creates an eternal battle as pressure forces air own a gradient while the Coriolis effect
deflects wind 90 degrees from its path. On the surface friction also plays a role. The
influence of the Coriolis effect is reduced as friction drag on earth’s surface slows wind
movement. Instead of blowing perpendicular to the isobars as gradient forces would sugest,
or parallel to them, as the Coriolis effect would cause, the wind ends up crossing isobars at
some angle between 0 or 90 degrees. Generally the pressure gradient determines speed; if the
gradient is steep the air moves quickly; if it is not so steep air will move less quickly.
2. Prepare and complete a table comparing the following characteristics of cyclones and
anticyclones.
Make sure to indicate where differences occur between northern and southern
hemispheres. (5 points)
relative pressure
vertical component (i.e., rising or sinking air)
horizontal component (i.e., diverging or converging air)
direction of flow (clockwise or counterclockwise)
likelihood of precipitation
Anticyclones
Relative Pressure: Relatively high pressure.
Vertical Movements: Air descends.
Horizontal Movement: Divergent
Direction of Flow: In upper atmosphere of the Northern hemisphere the wind move
clockwise parallel to the isobars. At lower elevations there is a divergent clockwise flow
with air spiraling out and away from the center of the anticyclones. Southern hemisphere
upper atmosphere = counterclockwise parallel to isobars. Surface layer = air diverges
counterclockwise.
Likelihood of precipitation: Less likely.
Cyclones
Relative pressure: Relatively low pressure
Vertical Movement: Air ascends
Horizontal Movement: Convergent
Direction of Flow: In the upper atmosphere of the Northern hemisphere air moves
counterclockwise parallel to isobars Air converges counterclockwise on the surface layer
of the earth. Southern hemisphere upper atmosphere = clockwise and parallel. Friction
layer = converges clockwise and spiral.
Likelihood of precipitation: Precipitation is more likely.
3. On a map of atmosphere pressure, what does the spacing of isobars tell you about
pressure gradients and wind speeds? (2 points)
The spacing of isobars indicated the pressure gradient. The closer the isobars are to one
another the greater the pressure gradient and therefore the higher the wind speeds.
Isobars that are more spaced out indicate a lower pressure gradient and lower wind
speeds.
4. Describe the three major wind belts of the general circulation of the atmosphere, the trade
winds, westerlies, and easterlies. Include key characteristics of each, including location,
origin and air movements. (5 points)
The Trade Winds: From the Equatorward side of the subtropic high’s and diverging
toward the West and towards the equator is wind system of the tropics. They cover most
earth between 25 N and 25 S. Over the oceans they remain prominent but do hover on
most land masses in this general vicinity. More prevalent than any other wind system.
They usually flow towards the West. They usually come from the North East in the
Northern hemisphere. They usually blow in the same direction at the same time at the
same speed and so they are the most consistent. They can hold an immense amount of
moisture. Potential for storms and precipitation, but not necessarily as they require
another force to allow them to actually “dump” the precipitation that they hold.
Westerlies: This wind pattern is issued from the poleward sides of the subtropic highs.
Occur in the midlatitudes between 30 and 60 degrees both North and South of the
equator. The winds are much less consistent and, in fact, they may come from any
direction. The winds are heavily influenced by surface friction, topographic barriers, and
especially from migratory pressure systems.
Easterlies: Located from the poles to about 60 degrees of latitude. The winds are cold
and dry but are also variable. However, they do generally move from East to West. They
help give rise to Polar Fronts.
5. Discuss the formation of the ITC and subtropical highs. What are typical weather patterns
found within each? (5 points)
Subtropical highs, known as STH’s, occur at each ocean basin, with large high pressure
cells centered at about 30 degrees of latitude. They are gigantic anticyclones developed
from the descending air of the Hadley cells. They are just off the west coast of the
continents. They are ridges of high pressure extending around the world. Weather is
almost always clear, warm, and calm. There is no wind and warm tropical sunshine.
Intertropical convergence zones are the area where air from the northern and southern
hemisphere meet. The area shifts due to the earths rotation and tilt. There are feeble,
erratic winds resulting from convergence and weak horizontal airflow. There is high
amounts of rainfall due to the low pressure. Thunderstorm activity is fairly common.
6. Explain the occurrence of land-sea breezes and mountain-valley breezes. Be sure to
address temperature and pressure differences, as well as vertical and horizontal air
movements. (8 points)
A sea breeze blows from the sea towards the land and usually occurs during the day. It
occurs in midalititude coastal areas. Land breezes occur in this area as well, and blow
from the land toward the sea. These breezes are caused by the differential heating of land
and water surfaces. During the day the land warms up rapidly causing the air above to be
heated by conduction and reradiation. The heating means that the air above will rise and
expand, creating low pressure on the surface, which in turn, attracts breezes from the
cooler ocean. Because the flow of air is relatively cool, the air temperature on coastal
areas will be significantly milder than further inland. At night, the air flow is weaker, as
the land and the air above it cool quicker then the ocean. This causes higher pressure on
lands and forces air out towards areas with lower pressure; the sea.
Mountain and valley breezes take place in, of course, hilly and mountainous areas.
During the day, air over the mountain slopes heats up quicker then air in the valleys,
again due to conduction and reradiation. The hot air rises, creating a low pressure area.
In the valleys air flows upward away from high pressure areas and towards the top of
mountains and hills. We call this a valley breeze. Clouds form around the peaks and, as
we all know in Boulder, afternoon showers occur regularly. At night, the mountain
slopes lose heat rapidly because of radiation, chilling the air, raising the pressure and
forcing winds down towards the valleys. These breezes are prominent in the winter.
LAB EXERCISE 11 AND 12