Text Flashcards
the __ parallel in western north America served as the border for US and Canada
49
US-CAN border longest nonmilitarized border in the world
IBC
International Boundary Commision established in 1908
IPCC(Intergovernmental Panel on Climate Change)
the lead international scientific body assessing the current state of knowledge about climate change and its impacts on society and the environment
Physical geographers study the environment by analyzing ____,___,____, and ______
air,water,land, and living systems
Geography defined
is the science that studies the relationships among natural systems, geographic areas, society, and cultural activities, and the interdependence of all of these over space.
-geography is the spatial consideration of earths processes interacting with human actions
spatial defined
refers to the nature and character of physical space, its measurement, and the distribution of things within it
5 original spatial themes of geography (explain each)
6 recognized by the US
- location
- identifies a specific address or absolute and relative position on Earth.
ex: This highway marker is at 23.26 degrees north latitude and 109.42 W longitude - region
- uniform physical or human characteristics.
ex: The east cape regions of Baja California Sur on the sea of cortez is known for windsurfing, diving, and the relaxed lifestyle of old mexico - human-earth relationships
ex: sustainable growth and water resources - movement
- Communication, migration, and diffusion across Earths surface represent movement in our interdependent world
ex: Carbo San Lucas receives over 2 million visitors each year - place
- No two places on earth are exactly alike. Place is the characteristics, both human and physical, of a location.
ex: Cienega de santa clara, a restored wetland on the Colorado river delta, is a specific study area and a new ecotourism destination.
spatial world, places and regions, physical systems, human systems, environment and society, and uses of geography in todays society
Two main fields of geography
Physical
-is the spatial analysis of all the physical elements, processes, and systems that make the environment
spatial analysis
the synthesis of many different topics from many fields, integrating info to form a whole earth concept
Earth System science
area of study that seeks to understand Earth as a complete entity, an interacting set of physical, chemical, and biological systems.
theory
constructed on the basis of several extensively tested hypothesis and can be revaluated or expanded according to new evidence
Scientific Method (6)
- Observations
- ask questions, observe nature, collect primary data
- search for patterns - Questions and Variables
- Hypothesis
- Testing
- Results
- Theory Development
less developed countries posses __% or about __ billion of the population
81
5.75
human denominator
totality of human impact on Earth
_______ is the name for the most recent years of geological history, when human have influenced Earths climate and ecosystems.
anthropocene
system
is any set of ordered, interrelated components and their attribution, linked by flows of energy and matter, as distinct from the surrounding environment outside the system.
-may comprise any number of subsystems
Define energy
Define matter
is a capacity to change the motion of, or to do work on, matter
is mass that assumes a physical shape and occupies space
open systems
systems in nature are general not self-contained: inputs of energy and matter flow into the system, and outputs of energy and matter flow from the system.
ex: earth an open system in terms of energy but not matter
- most natural systems are open in terms of energy
ex: hurricanes and tornadoes
4 types of energy that powers terrestrial systems
kinetic( motion) potential( position) chemical (setting fluid atmos in motion) mechanical (setting ocean in motion) -earth radiates energy back out in heat
closed systems
a system that is shut off from the surrounding environment so that it is self contained
-very rarely found in nature
feedback loops
pathways carrying ‘information’ that guide and sometimes control further system operations
define geographic term : information
outputs or system feedback acts as information that can guide and sometimes control further system operations
_____ feedback information discourages change in the system
negative
- further production of such feedback opposes system changes and leads to stability
- causes self regulation in a natural system
______ feedback loops are common in nature
negative
If feedback information encourages change in the system it is ______ feedback
positive
- further production of positive feedback stimulates system changes
- unchecked positive feedback can create snowball effect
- in natural systems this can lead to instability, disruption, or death of the organism
ex: global climate change
steady state equilibrium
an energy and material system that remains balances over time in which conditions are constant or recur is in a steady state condition
-when rates of inputs and outputs in the system are equal and the amounts of energy and matter in storage are constant
dynamic equilibrium
a steady state system demonstrating a changing trend over time
-slow changes allowed for and maintained by the equilibirum
cryosphere
portion of the hydrosphere that is frozen
geodesy
the science that determines Earths shape and size by surveys and mathematical equations
Earth’s shape is called ______ ______
oblate ellipsoid
-earths equatorial bulge and polar oblateness
geoid surface
earths geoid is a sea level surface that extends uniformly worldwide, beneath the continents
-heights on land and depths in the oceans measure from this hypothetical surface
Earths Polar circumference is ______km
Earths Equatorial Circumference is ______km
40,008
40,075
=67km
Latitude
is an angular distance north or south of the equator, measured from the center of earth. -run east to west, parallel to equator .equator assigned 0 degrees latitude .North pole= 90 degrees north latitude .South Pole= 90 degree south latitude
A line connecting all points along the same latitudinal angle is a _______
parallel
Latitude vs Parallel
Lat: is the name of the angle (49 degrees north latitude)
parallel: names the line (49th parallel)
from the equator to the poles a degree of latitude is fairly consistent, about ___km; at the poles a degree of latitude is slightly larger by _.__km then the equator
100
1.12
latitudinal geographical zones (9) from North to South
- Arctic- 66.5 to North Pole
- Subarctic- 55 to 66.5
- Midlatitude- 35 to 55
- Subtropical- 23.5 to 35
- Equitorial and Tropical- 23.5 N to 23.5 S
- Subtropical- 23.5 S to 35
- Midlatitude- 35 to 55
- Subantarctic- 55 to 66.5
- Antarctic- 66.5 to south pole
Longitude
is an angular distance east to west of a point on Earths surface, measured from the center of Earth
- run north to south
- A line connecting all the points along the same longitude is a meridian
Longitude
is an angular distance east to west of a point on Earths surface, measured from the center of Earth
-run north to south
-A line connecting all the points along the same longitude is a meridian
-meridians run at right angles(90 degrees) to all parallels including the equator
- as they converge towards the poles, the actual distance on the ground spanned by a degree of longitude is greatest at the equator and diminish to 0 at the poles
east has a positive value, west a negative
A line connecting all the points along the same longitude is a ______
meridian
longitude vs meridian
long= name of the angle
meridian= names the line
both measure distance both east and west of the prime meridian
prime meridian
a meridian designated as 0 degrees
-passes through the old royal observatory at Greenwich, england
Latitude is determined by sighting the ___ or the ___ ___.
Longitude is determined by the use of ____ and came much later then latitude
sun, North Star
time
Great Circle
is any circle of earths circumference who’s centre coincides with the centre of Earth
- every meridian is one half of a great circle that passes through the poles
- on flat maps, aircraft routes appear to arch their way across oceans and landmasses
- only one parallel is a great circle (equatorial parallel)
______ circle routes trace the shortest distances between two points on earth
great
_____ ______ is the only parallel which is a great circle
equatorial parallel
small circle
is any circle that has a centre that does not coincide with the centre of the earth
-all parallels, other the equator, are small circles
time system is based on _____ and the _____ ______
longitude and prime meridian
earth rotates at __ degrees per hour
15
360/24=15
Greenwhich Mean Time(GMT)
- 1884
- 24 standard meridians
- time zone of 1 hour spanning 7.5 degrees on either side of the central meridians
Coordinated Universal Time (UTC)
replaced GMT and became the legal reference for official time in all countries
-based on average time calculations from atomic clocks which were invented in early 1950’s
International Date line
the meridian 180 degrees on the opposite side of the Prime meridian
- marks the place where each day officially begins (12:01 AM)
- new days sweep westward from this point
- created by earth turning eastward on its axis
At the IDL, the ____ side of the line is always one day ahead of the ___ side
west
east
Daylight savings time
- followed by 70 countries
- set ahead 1 hour in the spring, 1 hour back in the fall
- extends daylight for early evening activities at the expense of early morning daylight
Daylight savings in spring is the _____ sunday of ____
Daylight savings in fall is the _____ sunday in ______
2nd of march
1st of November
map
is a generalized view of an area, usually some portion of the earths surface as seen from above and greatly reduced in size
scale
the ration of the image on a map to the real world
-relates to size of a unit on the map to the size of a familiar unit on the ground
3 types of scale
describe each
- representative fraction or fractional scale
. is expressed with either a colon or a slash
.no actual units of measurement are mentioned because any unit is applicable as long as both parts of the fraction are in the same unit - Graphic scale or bar scale
. is a bar graph with units to allow measurement of distances on the map
. an important advantage is that if the map is enlarged or reduced, the graphic scale enlarges or reduces along with the map
-does not work with fractions scale or written scale - written scale
1: 50,000,000= _____ scale
1: 10,000= _____ scale
small
large
-the greater the denominator in fractional scale or the number on the right in a ration expression, the smaller the scale of the map
small scale maps show:
a greater area with less detail
large scale maps show:
a smaller area in more detail
a _____ is the only true representation of distance, direction, area, shape, and proximity on earth
globe
Globe model characteristics in comparison to other map projections
- Parallels are always parallel to each other, always are evenly spaced along the meridians, and always decrease in length towards the poles
- meridians always converge at both poles and always are evenly spaced along any individual parallel
- The distance between meridians decreases towards the poles, with spacing between meridians at the 60th parallel equal to 1/2 the equatorial spacing
- parallels and meridians always cross each other at right angles
map projection
reduction of the spherical earth to a flat surface
-no flat map projection of earth can ever have all the features of a globe
selecting a map projection is based off of 2 properties where only one can be selected
- Equal Area (equivalency)
2. True Shape (conformality)
The main map projection classes include(3): give examples
name 1 nonperspective shape
cylindrical:
ex: Mercator Projection
- standard line
planar(azimuthal):
ex: Gnomonic Projection
- standard point
conic:
ex: Albers equal-area conic projection (two standard parallels)
- two standard lines
- Oval Projection
- standard line
Projections have a contact line/point between the wire globe and the projection surface (standard line or standard point) it is…
the only place where all the globe properties are preserved
- a standard parallel or standard meridian is a standard line true to scale along its entire length without distortion
- areas away from this critical tangent line or point become increasingly distorted
- should be centered
Mercator Projection
.shaped like a sheet of paper showing entire globe minus very top and bottom
. a cylindrical projection
. conformal projection with meridians appearing as equally spaced straight lines and parallels appearing as straight lines that are spaced closer together near the equator
. poles are infinitely stretched with the 84th N parallel and 84th S parallel fixed at the same length as that of the equator
-cut off near the 80th parallel in each hemisphere because of sever distortion at higher latitudes
. presents false notion of size (area) of midlatitude and poleward landmasses
-ex: Greenland looks larger then south America when in reality it is 1/8th the size
.great circle line appears curved
.rhumb line appears straight
Advantages:
.A line of constant direction, rhumb line, is straight and therefore facilitates plotting directions between two points
-useful in navigation and is standard for nautical maps
A _____ line on a Mercator map is straight and therefore facilitates plotting directions between two points
rhumb
- easy to follow as you can use one compass bearing
- not the shortest route though
- great circle shortest route
Gnomonic or Planar projection
.is a flat image of the top or bottom of a globe
.cannot show an entire hemisphere
. all great circle routes, which are the shortest distance between two points on Earths surface are projected as straight lines
. the great circle routes plotted on a gnomonic projection then can be transferred to a true-direction projection such as a Mercator, for determination of precise compass headings
.great circle appears as a straight line
.rhumb line appears as a curved line
GPS ______ _______ _______
GIS _______ ________ ______
global positioning system
Geographic information system
GPS
.instrument that receives radio signals from satellites, you can accurately determine latitude, longitude, and elevation anywhere on or near the surface of Earth
.comprises 27 orbiting satellites, in 6 orbital planes
-transmit navigational signals to Earth-bound receivers (backup GPS satellites are in orbital storage as replacements)
.GPS receiver senses signals from at least 4 satellites- a minimum of three satellites for location and a fourth to determine accurate time
-the distance between each satellite and GPS receiver is calculated using clocks built into each instrument that time radio signals travelling at the speed of light between them
Remote Sensing
the acquisition of information about distant objects without have physical contact
.Satellite remote sensing:
- physical elements of earths surface emit radiant energy in wavelengths that are sensed by satellites and other craft and sent to receiving stations on the ground
- receiving stations sort those wavelengths into specific bands, or ranges
infrared sensing(longer then visible light): .produces images based on temperature of objects on the ground
microwave sensing(longer then visible light): .reveals features below earths surface
radar sensing:
.shows land-surface elevations, even in areas that are obscured by clouds
photogrammetry
deriving accurate measurements from photographs
Geostationary(or geosynchronous) orbits, typically at an altitude of __,_____km are high earth orbits that effectively match earths rotation speed so that one orbit is completed in about 24 hours
35,790
used by many communications and weather satellites as they remain motionless and therefore satellite antennas do not have to move
GPS satellites, at altitudes of about __,___km, have a medium Earth orbit that moves more quickly then high earth orbit.
20,200
Low earth orbits at altitudes of less then __,___km are the most usefull for scientific monitoring
1,000
Satellites inclination: define
the angle of a satellites orbit in relation to Earths equator
.some satellites orbit near the equator to monitor earths tropical regions; this is low inclination orbit which acquires data only from low latitudes
.Monitoring the polar regions requires a satellite in polar orbit, with a higher inclination of about 90 degrees
Sun-Synchronous orbit
___ to ___ km altitude
.important for scientific observation
.low earth orbit is synchronous with the sun, so that the satellite crosses the equator at the same local solar time each day
.ground observation is maximized in sun synchronous orbit because earth surface viewed from the satellite are illuminated by the sun at a consistent angle
-allows for better comparison of images from year to year because lighting and shadows do not change
.600-800 km altitude
Passive remote sensing
.record wavelengths of energy radiated from a surface, particularly visible light and infrared
.our own eyes are passive remote sensors, as was appollo 17 astronaut camera that made the film photograph of earth
our own eyes are an example of ____ _____ _____
passive remote sensors
active remote sensing
.direct a beam of energy at a surface and anylyze the energy reflected back
- ex: radar: emits short bursts of energy that have relatively long wavelengths (0.3-10 cm) toward the subject terrain, penetrating clouds and darkness.
- energy reflected back to a radar receiver for analysis is known as a backscatter.
- radar images collected in a time series allow scientists to make pixel-by-pixel comparisons to detect earth movement, such as elevation changes along earthquake faults
.airborne LiDAR(light detection and ranging)
-collects highly detailed and accurate data for surface terrain using a lasar scanner with up to 150,000 pulses per second
backscatter
energy reflected back to a radar receiver for analysis
GIS
IS A COMPUTER-BASED DATA PROCESSING TOOL FOR GATHERING, manipulating, and analyzing geographic info
.spatial data is arranged in layers or planes containing different kinds of data
.first layer is a map with its associated coordinates in order for future layers to base off of
.capable of analyzing patterns and interrelationships within a sing data plane
.when the layers are combined, the resulting synthesis (a composite layer) is ready for use in analyzing complex problems
a ______ layer is when layers are combined in GIS
composite
Roger Tomlinson
.father of GIS
.created Canada Geographic Information System (1933-2014)
-was key in development the Canadian GIS
Geovisualization
is the technique of adjusting geospatial data sets in real time so that users can instantly make changes to maps and other visual models
-used to transform scientific knowledge into resources for non scientists like decision makers
Global Net Radiation
the balance between incoming short wave energy from the sun and all outgoing radiation from earth and the atmosphere-energy inputs minus energy outputs
isolines
lines connecting points of equal value, to show radiation patterns
the largest net radiation net radiation values, averaging __ W x m(-2) are above the ______ oceans
the lowest net radiation of -____ are over ______
the sahara is interesting as it shows a -20 because of constant clear skies
-lack of clouds and atmospheric pollution
80, tropical
114, antarctica
latitudinal imbalance, shown in the isoline image(pg 51) in energy is critical as it drives global circulation in the ______ and ______
atmosphere and oceans
Seasonal variations are a response to changes in the suns ________ or the angle between the horizon and the sun
altitude
zenith
when the sun is found directly overhead or at 90 degrees altitude
-when insolation is at maximum (subsolar point)
suns declination
is the latitude of the subsolar point
-declination annually migrates through 47 degrees of latitude, moving between the tropic of cancer and tropic of Capricorn latitudes
why are there seasons?
.result from variations in the suns altitude above the horizon, the suns declination (latitude of the subsolar point), and daylength during the year
- these are all created by physical factors:
- earths revolution in orbit around the sun, its daily rotation on its axis, its tilted axis, the unchanging orientation of its axis, and its sphericity
Earths revolution
orbit around the sun; requires 365.24 days to complete at 107 280 km/h
.Number based on the tropical year
-measured from equinox to equinox, or the elapsed time between two crossings of the equator by the sun
Earths rotation
when viewed from the north pole, the earth rotates __________ about its axis
Earth turning on its axis; takes approximately 24 hours
.when viewed from the north pole, the earth rotates counter clockwise about its axis (west to east)
.the linear velocity of rotation at any point on Earths surface varies dramatically with latitude as parallels shrink
-ex: 1675 km/h at equator
838 km/h at 60th parallel
0 km/h at poles
Earths tilt
___ degree angle
alignment of axis at about 23.5 degrees angle from perpendicular to the plane of the ecliptic (the plane of earths orbit)
.imagine a perpendicular (at a 90 degree angle) line passing through the plane
-from this perpendicular, earths axis is tilted about 23.5 degrees; it forms a 66.5 degree angle from the plane itself
Earths axial parallelism
unchanging (fixed) axial alignment, with polaris directly overhead at the North pole throughout the year
Earths Sphericity
oblate spheroidal shape lit by suns parallel rays; the geoid
.spherical shape causes the parallel rays of the sun to fall at uneven angles on Earths surface
Earth-Sun distance averages about ___ million km
aphelion to perihelion might seem a seasonal factor but it is not significant as it varies about __% (__ million km)
150
3, 4.8
the linear velocity of rotation at any point on Earths surface varies dramatically with latitude as _______ shrink
parallels
moons rotation and revolution are __________
counter clockwise like the earth
plane of the ecliptical
imagine a plane(flat surface) that intersects Earths elliptical orbit around the sun, with half of the sun and earth above the plane and half below
.earths tilted axis remains fixed relative to this plane as earth revolves around the sun
Tropic of Cancer: _________(Month) __(day)
Tropic of Capricorn: ________(Month) __(day)
June 20 or 21
. june solstice or summer solstice in the N hemisphere
- the subsolar point migrates from the equator to 23.5 degrees N
-the circle of illumination now includes the North polar region, everything North of the arctic circle receives 24 hour light
-south pole in complete darkness
December 21 or 22
-December solstice or N Hemisphere Solstice
.solstices are specific points in time at which the suns declination is at its position farthest north at the tropic of cancer or farthest south tropic of Capricorn
. circle of illumination excludes the north pole region from sunlight but includes the south pole region
-subsolar point is 23.5 degrees S latitude
.locations between 66.5 degrees N and 90 degrees N, the sun remains below the horizon the entire day
-66.5 parallel marks the arctic circle
_____(Month) Equinox or vernal equinox in the northern hemisphere occurs on ______(Month) ___(day)
_____(Month) equinox in southern hemisphere on _____(Month) ___(day)
March 20 or 21
.at this time the circle of illumination passes through both poles so that all locations on earth experience a 12 hour day and night
September 22 or 23
.Autumnal equinox in the northern hemisphere when earths orientation is such that the circle of illumination again passes through both poles
.subsolar point returns to the equator
Antipode
the point diametrically opposite on the other side of the Earth
Gradient
is a line along which the value of some measureable variable changes and the rate of change per unit of distance is greater for steep gradients and less for gentle gradients
Explain these 4 isoline map types
- Isotherm
- Isobars
- Isohyets
- Topographic Contours
- temp
- barometric pressure
- rainfall
- land elevation
Earths average distance from the sun lis ___ million km
150
_____ is the closest the earth is to the sun
_____ earths farthest position from the sun
perihelion-jan 3rd
aphelion-July 4th
sunspots
surface disturbances caused by magnetic storms
-appear as dark areas on solar surface
solar minimum vs. solar maximum
is a period of years when few sunspots are visible
is a period during which sunspots are numerous
solar wind
emmited clouds of electrically charged particles that surge outward in all directions from the suns surface
- takes 3 days to reach earth
- first interact with earths magnetic field
- deflects solar wind towards poles
magnetosphere
earths magenetic field
wavelength and frequency
didtsnance between corresponding points oon any two successive waves
the number of waves passing one point in 1 second
sun emits _____ energy
radiant
Wiens displacement law
everything on earth emits energy related to their individual surface temperatures: the hotter the object the shorter the wavelengths
thermopause
___ km above surface
region at the top of the atmosphere approximately 450 km above surface
-outer boundary of earths energy system and provides a useful point at which to asses the arriving solar radiation before it diminishes
solar radiation that is intercepted by earth is ______
INSOLATION
solar constant
average insolation received at the thermopause when earth is at an average distance from the sun
the only point where insolation arrives perpendicular to the surface is the _____ point
subsolar