Flashcards in Unit 1: Chapters 1, 3, and 4 Deck (54)
What does the study of geography include?
how things differ from place to place
requires a spatial approach to analysis divided into: human geo and physical geo
What does the study of physical geography encompass?
examines the spatial variations of natural phenomena
What four natural spheres are studied by Physical Geography?
lithosphere - curstal rocks and overlaying soils
atmosphere - mixture of gases which envelopes the Earth and sustains life
biosphere - includes all living organisms and all places where they exist
hydrosphere - water in all its forms
What is the approximate age of the earth?
4.5 to 5 billion years old
What does the Big Bang theory attempt to explain?
origin of the universe
What does the Dust Cloud Hypothesis attempt to explain?
origin of our solar system
What are the key formation steps of the Dust Cloud Hypothesis discussed in class?
dust left over from big bang, supernovas, etc. drew inward by gravity to become planets and stars. the density increased enough to form elements of solar system
As discussed in class, if the age of the earth were reduced to one year, approximately when would the following have occurred?
a. formation of the oceans
b. first life
c. blue-green algae and stramatolytes
d. completion of free oxygen in atmosphere
e. land plants and animals
f. climax of dinosaurs
1. formation of oceans - March 1st to June 1st (from the moisture in the air from volcanoes and ice comets)
2. first life - March 1st to April 1st (anarobic to bacteria)
3. blue green algae - May 1st (oxygen begins major production)
4. free oxygen - September 1st (levels they are today)
5. lands plants and animals - November 24th
6. climax of dinosaurs - December 16th
How can your latitudinal position be located in the northern hemisphere using the North Star?
the Northern star is at 90 degrees, so if you're directly under it, you're at the North Pole and if it is on the horizon, you are at the equator. Finding your angle compared the the North Star gives your location
What three gases make up 99.9% of the earth's atmosphere and what are their respective percentages?
Nitrogen - 78%
Oxygen - 21%
Argon - 0.9%
What direction does the earth rotate when viewed from above the North Pole?
Know how the rate of temperature change acts as a separation criteria for sorting out the four atmospheric layers.
earth to troposphere - temp is decreasing
troposphere to stratosphere - temp is increasing
stratosphere to mesosphere - temp is decreasing
mesosphere to thermospehere - temp is increasing
What is ozone and how is it formed?
high energy ultraviolet radiation strikes and oxygen molecule and causes two free oxygen molecule and causes it to split into two free oxygen atoms. The free oxygen atoms collide with molecules of oxygen to become ozone molecules. (So three oxygen atoms together is ozone)
What is the major ozone depleting element discussed in class and how does it deplete ozone?
Chlorine atoms are separated by sunlight from chlorofluorocarbon, and when they hit ozone molecules, it separates back into oxygen molecules
If the ozone in the stratosphere was compressed to sea level pressure and cooled to 32 degrees F, how thick would the layer be?
What is a Dobson unit as it relates to ozone values?
0.01 mm of ozone at 0 degrees C (32 degrees F) and one atmosphere pressure equals one Dobson Unit.
How does length of daylight vary from season to season?
There are always 12 hours of each daylight and nighttime at the equator.
March equinox - all get 12 hours of each
June solstice - n of equator gets more daylight and s of equator gets less
September equinox - all get 12 hours of each
December solstice - n of equator gets less daylight and s of equator gets more
Why does the difference in length of daylight and darkness increase as one goes poleward?
at the north pole, the sun rises on the march equinox and is above the horizon continuously for the next 6 months, it goes higher and higher until the june solstice, then it goes lower and lower until it sets on the september equinox
What is albedo?
The percentage of light reflected by an object
Have a general idea of how different earth materials would rank with regards to their albedo.
highest to lowest:
water when the sun is near the horizon
water when the sun is nearly vertical
What is the sky a blue color when the sun is high in the sky?
rayleigh scattering - with a clear sky, the blue light is scattered while the longer waves of green and red are not affected as much
Why is the sky a reddish or orange tint when the sun is near the horizon?
when the sun is near the horizon, the blue light is absorbed, red light passes most easily through the atmosphere and is scattered along the way
What is the "greenhouse effect?"
short wavelengths of visible light from the sun pass through the atmosphere and are absorbed, but the longer wavelengths of the infrared re-radiation from the heated objects are unable to go back out of the atmosphere, raising the temperature: global warming
Explain adiabatic heating and cooling
Adiabatic is the temperature change associated with pressure change - no loss or gain of total energy in adiabatic processes
warm air rises, air expands, air cools
cool air descends, air compresses, air warms
What does temperature change, but there is no gain or loss of heat energy in the air with adiabatic heating and cooling?
The pressure is causing the molecules to speed up and slow down.
What is latent heat?
stored energy, like the heat in condensation. when water turns into vapor and condensation, it releases some of the heat from within
What is differential heating and cooling?
Differential heating is when one area (in meterological situations land) heats faster than another area (a sea or a lake).
This causes air to flow across the border (the rising heated air pulls the cooler air into the volume it has vacated).
Why does water heat slower and cool slower than land? Provide three reasons discussed in class.
1. water is translucent, light can penetrate to around 600 feet
2. water circulates, redistributes heat
3. high specific heat (1.0)
Explain how Ocean currents (ocean gyers) help to distribute energy around the world, thus moderating the Earth's climate.
Acting at times as a climate and weather moderator, the surface temperature of the ocean affects air temperature over adjacent land. Cooler ocean currents and higher specific heat of water compared to land lead to minimal temperature fluctuation. Warmer currents can completely alter the weather and climate of a region. Comparing San Diego, California and Savannah, Georgia, both of which lie at 32 degrees north latitude, is a good example of this. According to the National Weather Service San Diego exhibits an average August temperature of 72 degrees Fahrenheit while Savannah is at 90 degrees.