earth's shape
Oblait Ellipsoid
Great circles
largest circle that can be produced by bisecting a sphere (the equator)
Small Circles
A circle on the globe's surface that does not bisect the center of the Earth. Parallels of latitude are examples of small circles.
meridians
great circles. lines of longitude that trend North/South and coincide with the poles. Spaced farthest apart at the equator
parallels
entire small circles that represent east/west lines and are always parallel to each other; intersect meridians at right angles
latitude
the arc of a meridian (north/south) between some point and the equator
longitude
the arc measured of a parallel between some point and the prime meridian
1 degree
60' min
non-variable gases (amount doesn't vary in time and space)
Nitrogen (78%)
Oxygen (21%)
Argon (.93%)
pure, dry air
variable gases
water vapor (0-4%)
carbon dioxide (.039%)
density
D=M/V
atmospheric pressure
Force/Area
Increases rapidly with height
measured in bars (barometer)
Troposphere
the lowest layer of the atmosphere, in which temperature drops at a constant rate as altitude increases; the part of the atmosphere where weather conditions exist; 7 miles thick; environmental lapse rate of 6.5degrees/1000m
Stratosphere
the layer of the atmosphere that lies between the troposphere and the mesosphere and in which temperature increases as altitude increases; contains the ozone layer; 10-30 miles above ground
Mesosphere
the coldest layer of the atmosphere, between the stratosphere and the thermosphere, in which temperature decreases as altitude increases; 50km
Thermosphere
the uppermost layer of the atmosphere, in which temperature increases as altitude increases
Ionosphere
the lower part of the thermosphere; layer of electrically charged particles in the thermosphere that absorbs AM radio waves during the day and reflects them back at night
Earth's Ocean (importance)
1. climactic - oceans retain a great deal of energy and moderate temperatures across the world
2. supplies water vapor to atmosphere
3. sustains vast assemblage of life
4. source of minerals
properties/dimensions of Ocean
1. covers 71% of earth; 3,800km deep
2. most physical/biological activity found at top where theres abundance of CO2 & O2
Solar Radiation
Transmission of energy from the sun in the form of electromagnetic waves.
factors limiting solar radiation
Revolution
1. ellipticity
2. perihelion
3. aphelion
perihelion
orbital point nearest the sun
aphelion
when earth is furthest from the sun
arctic/antarctic circle
66.5 degrees N/S
earth sits at same degree tilt
tropic of cancer
A line of latitude located at 23�30' NORTH of the equator. The Sun is directly overhead the Tropic of Cancer on the summer solstice in the Northern Hemisphere (June 20 or 21). It marks the northernmost point of the tropics, which falls between the Tropic
tropic of capricorn
A line of latitude located at 23�30' SOUTH. The Sun is directly overhead the Tropic of Capricorn on the summer solstice in the Southern Hemisphere (Dec. 20 or 21). It marks the southernmost point of the tropics.
June (summer) solstice
the time when the sun's declination is at the Tropic of Cancer at 23.5 degrees north latitude, June 20-21 each year (first day of summer) 24hrs of daylight at NP and 24hrs of darkness at SP
Winter solstice
On December 21-December 22, the shortest day and longest night of the Northern hemisphere due to the fact that the Sun is directly over the Tropic of Cancer
vernal equinox
March 21-22; Occurs when the Sun is directly overhead at the equator and results in day and night of equal length for both northern and southern hemispheres. 12hrs of daylight for all latitudes
autumnal equinox
Occurs in September, in the northern hemisphere, and marks the beginning of fall in the Northern Hemisphere; 12hrs of daylight for all latitudes
Solar Declination
the latitude where the sun's noon rays are directly overhead; occurs between the tropics, earth-sun relationship. the latitude where the sun is directly overhead at solar noon. controlled by the tilt of the earth. ranges from 23.5 degrees north to 23.5 de
angle of solar incidence
The angle at which the sunlight hits Earth's surface. This affects the intensity of the light. Because the smaller the angle the lower the intensity.
atmospheric thickness
amount of atmosphere penetrated by solar radiation; varies with angle of incidence; a thicker atmosphere increases the loss of solar radiation due to
1.absorbtion
2.scattering
3.reflection
potential energy
energy stored due to an object's position or arrangement
kinetic energy
the energy an object has due to its motion(gases,water vapor, wind, rain)
heat energy
energy released in the form of heat caused by the motion of moving molecules and the breaking of chemical bonds
radiant energy
energy propagated through space in the form of electromagnetic waves
conduction
heat transferred through material by molecular action
convection
heat transfer by fluid movement (gases & liquids)
radiation
the process of propagating energy through space in a wavelike or harmonic manner
the electromagnetic spectrum
gamma (short radiation)-->X-Rays-->UV-->visible light-->near-infared
physical radiation laws
anything warmer than absolute zero (0 kelvin) that radiates energy
the Stefan-Boltzman Law
the total amount of energy emitted by a blackbody is proportional to the 4th power of its absolute temperature
E=xT^4 (if T=2, T^4=16)
Wien's Law
The higher the temperature of a body the shorter the wavelength of it's maximum radiation. (hotter = shorter wavelength)
2897/Temperature of object
solar energy
energy from the sun that is converted into thermal or electrical energy
energy production of the sun
sun = shortwave radiation; 0-.4micrometers
the solar constant
the amount of solar radiation at the outer boundary of earth's atmosphere; perpendicular to earth's surface
global insolation
Uneven throughout the earth because of ground cover, clouds, angle, and water
world latitude zones
divisions that we use to describe climatic and other geographic zones; includes equatorial, tropical, subtropical, midlatitude, subarctic/subantarctic, arctic/antarctic, and polar zones
Insolation losses in atmosphere (WHY?)
1. scattering
2. absorption (the atmosphere greenhouse effect)
3. reflection
scattering (
why the sky is blue
)
the process by which small particles in the atmosphere deflect radiation from its path into different directions; lose radiation by back scatter
absorption
various gases absorb selectively at different wavelengths; O-Zone absorbs UV rays; h2o &co2 selectively absorb longwave (infrared) radiation at various wavelength peaks
the greenhouse effect
natural situation in which atmospheric gases trap heat energy and maintain the earth's temperature range; , The chemical bonds in carbon dioxide molecules absorbing solar energy and trapping it within the atmosphere. The trapping and returning of infrared
reflection
the bouncing back of a ray of light, sound, or heat when the ray hits a surface that it does not go through (clouds, ground, dust/molecules,)
49% is absorbed at earth's surface
Net Radiation
the difference between all incoming energy and outgoing energy carried by both shortwave & longwave radiation
***amount of energy entering atmosphere must = amount leaving
Latitude and radiation balance
-generally there is a net surplus of radiation at lower latitudes; amounts decline rapidly in middle latitudes reaching 0 at 40N/S latitudes
Poleward heat transfer
1. 75% accounted for by atmospheric (horizontal movement) advection in the form of sensible heat (warm air masses) and latent heat (water vapor)
2. 25% accounted for by warm ocean currents
temperature
a measure if the mean kinetic energy per molecule (speed) in an object
heat
an energy form; a measure of the total kinetic energy of all molecules
Tropical and Subtropical deserts
have the greatest diurnal temperature difference because of the amount of water vapor in the air
Annual Range
generally at a high maximum at middle and high latitudes over land with extreme values at about 65degrees related to the affects of continentality in asia and North America
Principle of Continentality
tendency of large land mass in middle & high latitudes to impose a large annual temperature range on the air temperature cycle
temperature near ground level
at dawn the air temperature is the coolest and at 3:00 its is the warmest
general points
1. both day and night temperature extremes are most likely to be found at ground level because ground surface is the most active heat exchanger in the soil-atmoshpere system
2. for a given height difference, greater differences in temperature are found ne
differential heating & cooling
it takes 3x as much heat energy to raise the temperature of h2o as it does soil; therefore land surfaces heat up more rapidly and greater than h2o surfaces
temperature patterns
1. the least annual temperature ranges occur in equatorial ranges
2. largest annual ranges in air temperature occur over land masses in mid/high heats
isobaric surfaces
surfaces of equal barometric pressure; pressure differences on earth's surface result from temperature differences
pressure gradient force
diff.Pressure/diff.Distance
the initial force that causes wind to blow
sea land breezes
daytime - land heats up rapidly causing a pressure gradient from sea to land - sea breeze
the coriolus effect
a deflective force resulting from earth's rotation- deflects objects to the right in the N. hemisphere & left in the SH
strengthens as a result of latitude and wind speed
anticyclone
a large-scale circulation of winds around a central region of high atmospheric pressure clockwise in the Northern Hemisphere. Air sinks within this type of system.
cyclone
a low-pressure center characterized by a counterclockwise flow of air in the Northern hemisphere
Monsoonal winds of SE Asia
formation of anticyclone (high pressure) winds; cold dense air flow from land to sea; low precipitation and clear skies
Summer winds
cyclones form over Pakistan; air flow takes moist unstable air over land-heavy precipitation;monsoon
santa ana winds
anicyclones over N. Great Basin (UT); blow from NE out to sea (hot dry winds); prevalent in fall months
Upper Level Winds
1. geostrophic winds-upper level winds that flow parallel to isobars
2. westerly winds & rossby winds
3. polar front jet stream-narrow zones of high wind speeds: 200mph
Ocean currents
pushed poleward by surface winds associated with high pressure cells; east side of continents there are warm currents; cool ocean currents on west side-sends it equatorward
phase changes
1.evaporation
2.condensation
3.sublimation
*the 3 states of water changes of states involve absorption or release of heat
specific humidity
the mass of water vapor contained in a kg of air = (g/kg)
dewpoint
the critical point at which air becomes saturated during cooling; below this point, condensation occurs usually producing water droplets
relative humidity
the ratio of water vapor present compared to the maximum quantity that could be , the ratio of the amount of water in the air at a give temperature to the maximum amount it could hold at that temperature (usually inverse related)
the dry adiabatic lapse rate
The rising and subsequent cooling of air at the rate of 10�C per 1,000 meters is called ________.
the wet adiabatic lapse rate
100% saturation 6�/1000m
Cloud forms
-cumilonimbus (vertical development)
-cirrus
-nimbostratus
-stratus
Cumulonimbus
a dark cloud of great vertical extent charged with electricity
cirrus
a wispy white cloud (usually of fine ice crystals) at a high altitude (4 to 8 miles)
nimbostratus
clouds that are low-level, uniform layer, usually very dark, that bring strong precipitation
stratus
Clouds that form in low, horizontal layers, cover all or most of sky