The following topics and concepts will be covered on your first midterm on Wednesday, March 3rd. This midterm will cover Chapters 1 through 4 to page 121. Topics covered in Monday's lecture (Atmospheric Circulation) will not be on the first midterm. They will be tested on the second midterm.

The midterm will consist of 30 multiple choice questions, 10 word bank questions, and one short essay. I have given you the four essay prompts for the exam essay, and I will chose one of these for the actual exam. Therefore I recommend that you prepare good outlines for how you would answer each essay question. BRING A BLUE BOOK and a SHORT SCANTRON, half page size.

Link to First Exam, full text

Topics and Concepts

The four spheres: atmosphere, hydrosphere, biosphere, lithosphere -- how do each of these interact with the others?


Closed, open systems,
steady-state equilibrium, dynamic equilibrium,
positive and negative feedback

(remember, "positive" doesn't mean "good"; "negative" doesn't mean "bad" when it comes to feedback.)
Examples of each of these concepts

Geographic Grid System

Parallels and Meridians, Longitude and Latitude, degrees, minutes, seconds
Equator, Prime Meridian, International Date Line, North and South Poles
Know the degrees and hemispheres for each of these so that you can draw and completely label a diagram of the Geographic Grid System (as in quiz 2). Include the special parallels & meridians.
Include degrees, hemisphere, lat or long, name of parallel or meridian

Earth-Sun relationship

Axis of rotation, angle of inclination (tilt of axis), orbital plane, perihelion and aphelion
Seasons and daily (diurnal) cycles at different locations
Significance (and degrees) of Tropics of Cancer and Capricorn, Arctic and Antarctic Circles,
Solstices and Equinoxes (what are they, when do they occur?)
Perihelion and aphelion, what they are, when they occur, effects?

Solar radiation (insolation) -- variations with latitude and seasons


Structure and composition
decreasing air pressure with elevation (decreasing density)
how temperature varies with elevation in troposphere
(average lapse rate 6.4 deg C/1000 m)
troposphere, tropopause, stratosphere, stratopause, mesosphere, mesopause, thermosphere
why does temperature drop with elevation in troposphere? why does it rise in stratosphere?

ozone layer
which gases make up atmosphere? In what proportions?
constant and variable gases, aerosols
(dust, volcanic ash, pollutant particles, etc.)
ozone depletion, where and why? What are the consequences?

Energy balance of the earth

Electromagnetic spectrum
Energy laws -- the hotter the body, the greater the amount of energy emitted; hotter the body, the shorter the wavelength; each body radiates energy at a range of wavelengths characteristic of the temperature of the body
Solar temperature ~6000 K; earth temperature ~288 K
shortwave and longwave radiation (SW & LW)
visible light (SW) -- where this is in the electromagnetic spectrum
earth's emission of heat, infrared radiation (LW)
shortwave UV absorption (by ozone) and scattering of shortwave (solar) radiation
(Why is the sky blue? Why are sunrise and sunset red or orange?)
albedo (reflection of shortwave radiation) off different surfaces -- high and low albedo
conduction and convection of longwave radiation (heat) at earth's surface
longwave radiation from earth heating atmosphere
greenhouse effect, greenhouse gases (name them?)

Modes of energy transfer (one body to another): conduction, convection, radiation


Difference between "heat" and "temperature", molecular kinetic energy

Controls on temperature from place to place

latitude -- seasonality, day length, earth-sun geometry
altitude -- decrease in air pressure (density), decrease in temperature, 6.4 deg C/1000 meters
cloudiness, fog (reflects SW; absorbs and reradiates LW)
continentality and marine effects -- land-water differences --
Continents dry, large seasonal and diurnal temp range; Marine moist, small seasonal and diurnal temp range
specific heat of water compared with rock, soil (specific heat of land versus water)

ocean currents, carry heat from low latitudes to high latitudes
surface cover, vegetation (albedo of surfaces, evaporation, shade, etc.)

Modes of energy transport -- ways that heat is carried from areas of surplus (tropics) to deficit (high latitudes)
Ocean circulation -- heat carried by ocean currents such as Gulf Stream
Atmospheric circulation -- heat carried by major winds, e.g. tropical air brought to higher latitudes by hurricanes
Latent Heat -- heat used to evaporate water, stored in the water vapor molecules and released as Sensible Heat when water condenses or freezes -- most important mode of heat transport to high latitudes

Temperature statistics -- means, temperature range (annual, seasonal, daily)
(e.g. where in the world is the seasonal temp. range highest? where is it lowest?

Study maps in text, also on Univ of Oregon web site

Air Pressure:
High Pressure -- Sinking air, Associated with stable air, sunny skies (not necessarily warm temperatures)
Low Pressure -- Rising air, Associated with unstable air, clouds, maybe precipitation
Cold air-- tends to be higher pressure, dense because cold
Warm air -- tends to be lower pressure, less dense because warm
Air pressure, Gravity -- highest pressure near sea level, air pressure decreases with altitude

Driving Forces in the Atmosphere (Why does the wind blow?):
Pressure Gradient Force -- pulls air from High Pressure to Low Pressure
Coriolis Force --bends air to right in the No. Hemisphere, to the left in So. Hemisphere; none at equator, strongest at poles; strongest at high velocities, none at zero velocity
Resisting forces: Friction -- slows down surface winds, causes winds to blow more toward center of lows
Cyclone: air circulating into a low pressure cell, counterclockwise in N. Hemisphere
Anticyclone: air circulating out of a high pressure cell, clockwise in N. Hemisphere

Last updated 2/24/10