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FINAL STUDY GUIDE
METO 1010
INTRODUCTION TO METEOROLOGY
FALL 2009
READ THIS FIRST: this outline is not meant to be fully comprehensive. This lists all the major topics we discussed in class,
but it does not completely cover everything involved with every topic, so use this as a guide to your notes, and to what
to look at in the text.
WHAT THE EXAM WILL COVER: The exam will cover the entire semester’s material. New material covered by the exam
will include some information on air pressure and winds (Ch. 6), air circulation (Ch. 7), air masses (Ch. 8) and midlatitude cyclones (Ch. 9). Use the study guides for midterms 1, 2 and 3 to review old material, and use this study guide
to review the new material.
WHEN THE EXAM WILL TAKE PLACE: The final will take place at the official, University – scheduled, time in your
regular classroom. You should look up the official times of all your finals at www.uvu.edu; from the UVU home page,
follow the ‘calendar,’ ‘academic calendar’ and ‘final exam schedules’ links.
INSURANCE: Insurance is not available for the final. This does not mean that you shouldn’t do the recommended
homework.
Outline of what we have covered:
1. Air circulation (Ch. 7)
a. Scale: microscale, mesoscale, macroscale. Understand what these are, there sizes and durations (time), and
examples of each.
b. Mesoscale winds that we discussed. Know what they are and what causes them
i) Land and sea breezes
ii) mountain and valley breezes
iii) Chinook winds (called Foehn winds in Europe)
iv) Katabatic winds
c. Global circulation
i) Simple one cell model (i.e., figure 7-6 in your text).
(1) be able to draw and explain the rational for this. Also be able to explain why its wrong
ii) Three – cell model. This is the good one that pretty much works.
(1) be able to draw it in side view and the surface winds that it explains
(2) be able to name and list the characteristics of the various surface winds and boundaries between them:
(a) NE and SE tradewinds
(b) Prevailing westerlies, north and south
(c) Polar easterlies, north and south
(d) equatorial low (doldrums), horse latitudes, polar front
(e) Be able to explain and describe how and why the patterns of this model change with the seasons
(boundaries and wind belts move north and south in winter and summer).
iii) Monsoons
(1) winter and summer, dry and wet
(2) driven by extra cooling and heating of continent vs ocean
(3) strongest in Asia because it’s the biggest land mass on Earth
(4) summer monsoon sucks moist air in from oceans, can cause huge amounts of rainfall over coastal areas in
June – September (up to 25 meters of rain!!!).
(5) North American monsoon
(a) much less strong than Asian, but significant nonetheless
(b) affects Arizona, and sometimes Utah
(c) strongest in late summer (why not strongest at the solstice?)
iv) Polar Jet stream
(1) Upper troposphere
(2) along the polar front
(3) Strong pressure gradient at polar front in upper atmosphere – pressure aloft over cold air from north is lower
than pressure aloft over warmer air in midlatitudes. Creates a strong pressure gradient that pushes air to the
north, then coriolis force bends it to the right and the jet stream blows west to east parallel to the isobars/equal
pressure surface contours.
(4) Can travel at speeds up to 500 kmh (300 mph), but 75 to 125 mph speeds are more common (in the winter).
It is slower in the summer.
METO 1010, Introduction to Meteorology, Final Study Guide, Prof. Bunds, UVU
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(5) The Jet Stream (Polar Jet Stream, technically) is very powerful and important – as discussed in the chapter on
weather patterns and fronts, mid-latitude cyclones typically initiate as waves in the polar front and the polar jet.
v) El Nino/Southern Oscillation (ENSO)
(1) Usual conditions
(a) Southeast tradewinds drive southern equatorial ocean current from east to west;
(b) High pressure exists near 30oS, coast of S. America, drives tradewinds.
(c) carries cool eastern boundary current (Peru current) waters to west.
(d) Water warms as it flows along the equator; water is warm at equator in western pacific (but cold in eastern
pacific)
(e) Peru current, westward Eq. Current creates upwelling along S. American coast (productive fisheries based
on phytoplankton, anchovies).
(2) ENSO conditions
(a) High pressure fails; Tradewinds fail – can even reverse; Southern equatorial current fails; water along the
equator and off Peru warms by solar heating, and warm water in western pacific even migrates to east
(b) Waters along S. American coast warm markedly – up to 9oC!!
(c) Upwelling shuts off, fisheries crater.
(d) Eastward water flow usually starts in fall, reaches eastern pacific midwinter
(3) Recent large ENSO events were 1982 – 1983 and1997 – 1998 (1/1/82 to 12/23/83 & 1/1/97 to 3/10/98
roughly). 82-83 was strongest on record.
(4) La Nina is the opposite
(a) Strong SE Tradewinds
(b) Generally reverse local effects
Air Masses (Ch. 8)
a. An air mass is a large body of air with consistent properties throughout it. Most important properties are temperature
and humidity. They are several hundred or more miles across and miles thick (high). It is implicit in the definition
that air outside or beyond an air mass has different characteristics.
b. Source regions and classification of air masses.
i) Air masses are primarily classified based on their temperature and humidity, which result from their source
region. A source region is a place where air masses form.
ii) Air masses are classified based on temperature using the following nomenclature
(1) arctic (A) for very, very cold air masses that originate in the Arctic, near the north pole
(2) polar (P) for very, cold air masses that originate at high latitudes
(3) tropical (T) for warmer air masses that originate south of the U.S.
iii) Air masses are classified based on humidity using the following nomenclature
(1) marine (m) for humid air masses that form over the ocean
(2) continental (c) for dryer air masses that form over land or over the arctic ocean when it is covered with ice
(so the air doesn’t evaporate much water and is relatively dry).
iv) Familiarize yourself with figure 8-3. Its pretty easy when you use some common sense and combine the ideas
of temperature, humidity and source region.
c. Lake Effect snow
i) enhanced snowfall downwind from large lakes
ii) especially important east of the Great Lakes
iii) Happens downwind from the Great Salt Lake, most often southeast of the lake (storm winds often blow from
the northwest)
iv) Caused when cold, unstable air blows over warm lake, water evaporates from water into air, increasing its
humidity and therefore the amount of snow it produces (when it hits the mountains west or southwest of the Great
Salt Lake).
Weather Patterns & Mid-latitude cyclones (Fronts!)
a. Basic concept of a front – boundary between two air masses.
b. Warm fronts and cold fronts – know these, be able to explain and sketch them
i) long-lasting, relatively gentle precipitation vs. short-lived, strong precip, often with thunderstorms.
c. Dry lines and stationary fronts - know these, be able to explain and sketch them
d. Mid-latitude cyclones
i) Big weather-maker (storms) in the U.S.
ii) Basic description:
(1) Low pressure center
(2) cold air is sucked towards the L from northwest
(3) warm air is sucked towards the L from south
(4) warm front and cold front form (be able to draw a sketch of this like we did in class!!)
iii) More depth to the idea
METO 1010, Introduction to Meteorology, Final Study Guide, Prof. Bunds, UVU
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(1) Cold front catches warm front, forming an occluded front.
(2) Whole system moves roughly west to east with westerlies and polar jet
iv) Formation
(1) Initiate as waves in the polar front and polar jet (see figure 9-10)
(2) Strengthen as they move east
(3) Become occluded, weaken
(4) Also often weaken as they pass over the Rockies, then re-form over the Great Plains
v) More advanced ideas
(1) Upper-air support from divergence aloft
(2) Convergence aloft supports anti-cyclones (High pressure centers)
STUDY QUESTIONS
If you want to turn these in forinsurance, please be sure to neatly answer them in complete sentences on separate
sheets of paper and staple everything together! Note that if you score below C- on the exam you can receive points
equivalent to a C- by doing these questions AND the suggested problems from the back of the appropriate chapters AND
turning them all in before the end of the testing period. The suggested chapter and web problems are listed on the course
syllabus.
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Be sure you understand air pressure & winds.
Be sure you can sketch isobars given a map that has sea level pressure marked at various locations on it.
What is a ridge (i.e., of high pressure)? Illustrate your answer by drawing a sketch isobars around a ridge of high
pressure.
What is a trough (i.e., of low pressure)? Illustrate your answer by drawing a sketch isobars around a trough of low
pressure.
What is the prevailing wind direction in Utah?
Where in the atmosphere is friction important to winds?
In what ways does friction affect winds?
Explain what microscale air circulation is, and give an every-day example of it. In your explanation, be sure to include
both its size and duration.
Explain what mesoscale air circulation is, and give an every-day example of it. In your explanation, be sure to include
both its size and duration.
Explain what macroscale air circulation is, and give an every-day example of it. In your explanation, be sure to include
both its size and duration.
Explain what a sea breeze is, using words and a sketch. Be sure to show what it is and why it happens (including the
time of day).
Explain what a valley breeze is, and how one forms (including the time of day).
Describe what a Chinook wind is, and give an example of it is common. What does the word Chinook mean?
What is a katabatic wind? Are they hazardous?
Carefully draw a 3 cell model for global air circulation like we did in lecture. Use an entire sheet of paper. Draw both
the vertical air movements and the surface winds.
Label all the surface winds and the boundary zones (doldrums, etc.) on your drawing of the global air circulation
model. Also label areas that usually have relatively high and low pressure.
What is the origin of the name Horse Latitudes for the region at about 30oN? What is typical weather for the Horse
latitudes?
What is typical weather at the equator?
What is typical weather at the polar front? Where is the polar front?
Explain how your model of global air circulation changes with the seasons, and explain why it would change.
Are you familiar with all of Earth’s major wind and climate belts, as shown on the drawing you made to answer
question 12?
Thoroughly explain monsoons. In your explanation, you should include both winter and summer monsoons, the
weather with each type, the cause(s) of the monsoons, and where and when in the world they happen.
Where does the Polar Jet form relative to your global air circulation model?
Which direction does the polar jet typically blow?
How fast does the polar jet typically blow?
Air pressure gradients drive winds. What is the origin of the air pressure gradient that drives the Polar Jet? In which
direction does the jet blow relative to the gradient?
How high is the Jet, typically?
Is the Jet stronger in winter or summer? Why?
At what latitude would you expect to find the Jet in the winter? In the summer?
METO 1010, Introduction to Meteorology, Final Study Guide, Prof. Bunds, UVU
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30. What are the major atmospheric (and oceanographic changes) (e.g., pressure, air movement, temperature (including sea
surface temperatures, fisheries) along the tropical Pacific that cause and result from ENSO? [Great additional ENSO
info is available at http://www.noaa.gov].
31. How does ENSO relate to the global air circulation model? If the winds and air pressures were always as you drew
them, would there be an ENSO? How do they change when there is an ENSO?
32. Explain the effects of ENSO (both the La Nina and El Nino components) on the U.S. Use a sketch to aid your answer.
33. Define what an air mass is.
34. Explain how air masses are named and labeled (i.e., mT, cP, etc.).
35. Draw a sketch of North America. On your sketch, draw the source regions and paths of the common air masses of the
region – show where they form and how the move over the U.S. Be sure to label all the air masses with the appropriate
names.
36. What air masses are most important to Utah’s weather?
37. Explain air mass modification.
38. Explain, using words and a sketch, what lake effect snow is, and how it is created. Where is lake effect snow
common? Be sure to include effects of humidity, temperature, and stability on air to create lake effect snow.
39. What two air masses sometimes collide over the central and SE (southeast) U.S. to produce ‘drylines?’
40. Draw a side-view sketch of a warm front. Be sure to label the temperature of the air masses and their movement.
41. What type of weather (and weather changes) would you normally experience as a warm front passes over you in Utah?
Be sure to include temperature, winds and precipitation in your explanation.
42. Draw a side-view sketch of a cold front. Be sure to label the temperature of the air masses and their movement.
43. What type of weather would you normally experience as a cold front passes over you?
44. Draw a side-view sketch of a (cold-type) occluded front. Be sure to label the temperature of the air masses around the
front and show their movement.
45. What type of weather can an occluded front cause? How long do occluded persist for?
46. Sketch a mid-latitude cyclone, including air pressure and fronts.
47. Draw a series of three sketches that shows the typical evolution of a mid-latitude cyclone, showing the positions of the
warm, cold and occluded fronts that commonly are part of a mid-latitude cyclone.
48. Why are mid-latitude cyclones important to residents of Utah and the U.S.?
49. What is the Norwegian model for the formation of mid-latitude cyclones? Explain it, and include how meteorologists
believe waves in the Polar Jet Stream generate mid-latitude cyclones.
50. How can upper-air flow support or weaken a mid-latitude cyclone?
51. How are anti-cyclones affected by upper air flow?
METO 1010, Introduction to Meteorology, Final Study Guide, Prof. Bunds, UVU
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