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
Net radiation is highest at _______
lowest at_______
tropical oceans
anarctica
atmosphere around for ___ billion years
4.6
4 distinct temperature based Atmosphere layers
- _______=-
- ______=-
- ______=-
- ______=-
.bound by gravity
- Thermosphere(heat sphere)= 80km-480km
.within heterosphere
.upper limit is thermopause
. can swell and unswell(raise or lower in altitude) based on solar activity
. high kinetic energy in vibration of molecules
-measured as temperature - Mesosphere= 50-80km above earth
.within homosphere
.outer boundary is mesopause
. mesopause is the coldest part of the atmos - Stratosphere= 18-50km
.temps increase with latitude in this layer
.outer boundary calles stratopause
.holds the ozone layer
.chlurofluorocarbons on rise while ozone decreasing - Troposphere=0-18km
.supports life, biosphere and contains weather
. 90% of total mass of atmos is here (bulk being water vapour, air pollution, and clouds)
. tropopause is outer layer (-57 degrees celcius)
. tropopause fluctuates with temperature of land below so equator pushes it to 18 whiles at poles its around 8km
-tropopause keeps prevents whatever is in the cooler(denser) air below from mixing into warmer stratosphere
TEACH SHARON MATH TONIGHT
exosphere
beyond 480 km altitude
gravity compresses air, making it _______ At earths surface
denser
heterosphere
80-480km altitude
. is the outer atmosphere in terms of composition
. 0.001% of the atmospheres mass is found here
.gases not evenly mixed
homosphere
80km-earths surface
.blend of gases nearly uniform throughout
-only exception is the ozone layer from 19-50km asl
ozone layer is found between __km and __ km asl
19-50
______ makes up 78% of the homosphere
nitrogen
- vast reservoir
- integrates through food we eat
oxygen makes up __% of the homosphere
20
-a by-product of photosynthesis
-
carbon dioxide
climatic threshold of ___ppm to be reached in 2020s
. natural biproduct of lifes processes
- important to global temperatures
- CO2 percentage increasing due to human activity
- burning fossil fuels
450
Heat VS. Temp
Heat= is created when kinetic energy is transferred between molecules and thus between bodies or substances
-resulting in temp difference between them
Temp=is a measure of the average kinetic energy of individual molecules in matter
Why could we feel heat at earths surface and not in the thermosphere?
the density of molecules is so low that little actual heat is produced
at surface the atmosphere is denser, greater number of molecules transmits their kinetic energy as sensible heat, meaning we can measure and feel it
sensible heat
meaning we can measure and feel it
______ is the coldest part of the atmos
mesopause
Normal Lapse rate is __ degrees celcius per km
explain
environmental lapse rate
6.4
.is an average
the actual lapse rate may vary considerably because of local weather conditions
Two zones in atmosphere based on function:
- Ionosphere=50-480 km
.outer layer
.absorbs cosmic rays, gamma rays, xrays, and shorter wavelengths of ultraviolet radiation,
. changing atoms to positively charged ions and giving the ionosphere its name
.hold northern lights
. inner layers include D,E,F1,F2 - Ozonosphere=0 to 50 km
.contains increased level of ozone
.ozone is a highly reactive oxygen molecule
.ozone absorbs the shorter wavelengths of UV
. UV converted to heat energy
. UVA 320-400 nm is not absorbed and makes up 95% of all UV radiation that reaches surface
T OR F
natural sources produce greater quantities of air pollutants than do sources attributable to humans
T
3 natural most significant sources of air pollution
volcanoes(sulphur oxide), forest fires(carbon dioxide), dust storms
aerosols
particulates produced by certain events like pollen release
.the diverse mixture of fine particles, both solid and liquid, that pollute the air and affect human health is reffered to as particulate matter
human made air pollution has caused __ million deaths worldwide
1.3
photochemical smog
responsible for hazy sky and reduced sunlight
.results from interaction of sunlight and combustion products in automobile exhaust, primarily nitrogen oxides and volatile organic compounds such as hydrocarbons that evaporate from gasoline
_____ _____ is the chemical that interacts with water vapour to create acid rain
nitric acid from nitrogen dioxide
main sources of sulphur dioxide:2
coal-burning electric utilities and steel manufacturing
the diverse mixture of fine particles, both solid and liquid, that pollute the air and affect human health is referred to as _______ matter
particulate
particulate matter of __ um or less in diameter pose the greatest health risks
- 5
pm0. 1 is new and even more dangerous
Air pollution is made worse by 3 factors
wind
-gather and move pollutants
local and regional landscape characteristics
temperature inversions in troposphere
CAA
US Clean Air Act 1970
still no such legislation in Canada
sea ice reflects __-__% of solar energy it receives
ocean surface reflects about __% of solar energy it receives
80-95
10
Transmission
refers to the uninterrupted passage of shortwave and longwave energy through either the atmosphere or water
Earth-atmosphere energy budget is comprised of ___wave radiation input(ultraviolet light,visible light, near infrared wavelengths) and ___wave radiation outputs(thermal infrared wavelengths)
short
long
energy defined
as the capacity to do work, or move matter`
kinetic,potential energy
kinetic: is the energy of motion
- produced by vibrational energy of molecules that we measure as temp
potential: is stored energy that has the capacity to do work under the right conditions
- potential converts into kinetic energy
two types of heat energy
sensible heat:
. can be sensed by humans as temperature, because it comes from the kinetic energy of molecular motion
Latent heat:
. is the energy gained or lost when a substance changes from one state to another, such as from water to ice (liquid to sold)
.differs from sensible heat transfer in that as long as physical change in state is taking place, the substance itself does not change temperature
How is heat transferred?
Radiation
. is the transfer of heat in electromagnetic waves such as that from the sun to earth
conduction
. is the molecule to molecule transfer of heat energy as it diffuses through a substance. As molecules warm, their vibration increases causing collisions that produce motion in neighboring molecules thus transferring heat from warmer to colder material
.convection(vertical) ocean currents vs advection( horizontal motion) wind flows
insolation
incoming solar radiation is the single energy input driving the earth-atmosphere system
scattering
incoming radiation is redirected, changing the direction of the lights movement without altering its wavelengths
-result from interaction with atmospheric gases
.accounts for a percentage of insolation that does not reach earths surface
-reflected back to space
.incoming energy that reaches earths surface after scattering occurs is diffuse radiation
-weaker radiation composed of waves travelling different directions
diffuse radiation
incoming energy that reaches earths surface after scattering occurs is diffuse radiation
-weaker radiation composed of waves travelling different directions
Rayleigh scattering
principle applies to radiation scattered by small gas molecule and relates the amount of scattering in the atmosphere to wavelengths of light
- shorter wavelengths are scattered more, longer are scattered less
- blues and violets are the shorter wavelengths then orange and red
- at its lowest spot on the horizon, shorter wavelengths are scattered out leaving only longer wavelengths(red and orange)
Insolation effected by 5 factors
- Scattering
- Refraction
- Reflection and Albedo
- Absorption
- Clouds, Aeosols and atmos albedo
refraction
.as insolation enters the atmosphere it passes from one medium to another, from virtually empty space into atmospheric gases
. a change in medium also occurs when insolation passes from air into water
.insolation subjected to change of speed which also shifts its direction through a bending action
-ex: mirage, setting sun, rainbow
.adds 8 minutes of daylight
.can see sun about 4 minutes before it peeks over horizon
Reflections and Albedo
. a portion of the arriving energy bounces directly back into space
. reflective quality of a surface is albedo
-affected by cloud and ground cover
-19-38% albedo between tropics, up to 80% at poles`
earth and its atmosphere reflect about __% of all insolation when averaged over the year
31%
absorption
.insolation, both direct and diffuse, that is not part of 31% reflected from earth is absorbed either in the atmos or by the surface
.is the assimilation of radiation from one form to another
. 45% by land and water
.24% by atmos gases, dust, clouds, and ozone
-selective about the wavelengths they absorb hence lower percentage
.converted to longwave energy or chemical energy
-raises temperature of absorbing surface
Insolation is absorbed:
__% by land and water
__% by atmos gases, dust, clouds, and ozone
45
24-selective about the wavelengths they absorb hence lower percentage
oxygen and ozone effectively absorb _______ radiation
do gases absorb visible light?
water vapour and carbon dioxide are good absorbers of ____wave radiation emmited by earth
ultraviolet
no
long
clouds, Aerosols, and atmos albedo
.presence or absence of clouds can make a 75% difference in the amount of energy that reaches the surface
.clouds reflect shortwave insolation and absorb longwave radiation leaving earth (can create warming affects-greenhouse)
.affects of clouds depends on cloud cover percentage, cloud type, altitude, and thickness (water content and density)
presence or absence of clouds can make a __% difference in the amount of energy that reaches the surface
75
Greenhouse concept
glass is transparent to shortwave insolation, allowing light to pass through to the soil, plants, and material inside where absorption and conduction take place
absorbed energy is then emitted out as longwave energy heating up the air inside the greenhouse
glass holds in both heat and longwave energy preventing it from mixing with the cooler outside air
glass a one way filter
in atmosphere longwave energy is not trapped rather its passage is delayed as long wave radiation is absorbed by gases, clouds, and dust and reradiated back to earth
cloud-albedo forcing vs cloud greenhouse forcing
refers to an increase in albedo caused by such clouds, and the resulting cooling of earths climate
- albedo effects exceed greenhouse effects
ex: low, thick stratus clouds reflect about 90%
refers to clouds acting as insulation, trapping longwave radiation from earth and raising minimum temperatures
- causes warming of earths climate
- greenhouse effects exceed albedo effects
ex: high altitude ice crystal clouds reflect only about 50%
What effect do Jet Contrails have?
jets produce high cirrus clouds which both cool and warm the atmoshphere, which makes it difficult to understand overall change it creates
_____ clouds are found low altitude and are cloud albedo forcing
_____ clouds are found high lat and are cloud greenhouse forcing
stratus
cirrus
Earth-Atmos energy balance: defecit, surplus, or equal
seperately the atmos has a deficit, surface has a surplus, and together are equal
Out of 100% of arriving solar energy:
__% is reflected back to space. __% scattering, __% reflected by clouds and aerosols, and __% reflected by earths surface.
another __% is absorbed by the atmos. __% by clouds, __% by atmospheric gases and dust, stratospheric
ozone absorption accounts for __%
__% transmits through earth’s surface as direct and diffuse shortwave radiation
31 (average albedo), 7, 21, 3
21, 3, 18,(atmos heating)
3
45(surface heating)
Earths atmos and surface absorb __% of incoming shortwave information
Total longwave radiation radiated to space (surface losses+atmos losses)= __%
69
69
Energy balance between incoming solar radiation and outgoing radiation exist around the __ parallels in N and S
In between them exists an energy ______
North of the tropics and south of the tropics past the point of balance exists an energy ______
36
surplus
deficit
during a 24 hour day highest daily temp occurs around __ pm or __ pm
3,4
.time of highest temp does not perfectly line up with time of most insolation because there is a lag
-occurs when a maximum of insolation has been absorbed and emmited to the atmos from the gorund
What is the boundary layer?
lower atmosphere at earths surface
microclimatology
is the science of physical conditions, indluing radiation, heat, and moisture, in the boundary layer at or near earths surface
-microclimates are local climate conditions over a relatively small area
Net radiation at the ground level involves ___wave rad coming down and going down into the ground. At night the heat transfers from going down to moving up toward the surface and out as ___wave radiation
short
long
How does the earths surface dissapate/lose heat? 3 Non-radiative processes that move heat from surface to the boundary level include
- Latent heat of evaporation is the energy that is stored in water vapour as water evaporates. Water absorbs large quanitities of latent heat as it changes state to water vapour, therby removing this heat energy from the surface. Also works in reverse when it rains
- dominant expenditure of earths entire NET R, especially over water surfaces
- mostly occur in tropics and decrease towards poles - Sensible heat is the heat transferred back and forth between air and surface in turbulent eddies through convection and conduction within materials. depends on temperature differences
- 1/5 of earths entire NET R is mechanically radiated especially over land
- mostly in dry regions
- highest in tropics - Ground Heating and cooling
is the flow of energy into and out of the ground surface (land or water) by conduction
-stored energy from spring and summer is averaged by the losses in fall and winter
Urban heat island effect: Cities are usually about _ degrees higher then suburban ares
6
define temperature
is a measure of the average kinetic energy of individual molecules in matter
-temp is a measure of heat
-___ degrees celcius is absolute 0 where molecular motion ceses
-273
Land Surface Temperature
satellites do not measure air temperature in the same way as a thermometer, instead measuring LST or land “skin” temp which is heating of the land surface and is often much hotter then air temp
ex: sand temp vs air temp
5 factors that influence temp variations
- Insolation
- latitude
- intensity of incoming solar rad - altitude and elevation
- temps decrease with increase alt because of creased density - cloud cover
- reflect and absorb radiation
- most variable factor - land-water heating differences
- water bodies tend to have more moderate temp patterns, continetal has more temp extremes
- land heats and cools faster then water
- evaporation,transperency,specific heat,movement,ocean currents and sea surface temps
Elevation vs. Altitude
refers to height of a point on earths surface above some plane of reference like ASL
ex: height of mountain resort
refers to airborne objects or heights above earths surface
ex: jet planes height
5 Reasons for Land -Water temperature differences
- Evaporation
- 84% of all evaporation comes from oceans - Transperency
- ground (opaque) vs. water (transperent)
- light hits the ground and is immediately absorbed
- light hits water and is distributed evenly throughout - Specific Heat
- energy needed to increase the temp of water is greater then that of soil - Movement
- water is fluid and capable of movement - Ocean currents and sea-surface temps
- warm or cold currents
- gulf stream carrying warm water up into the north atlantic
specific heat
the heat capacity of a substance
.water can hold 4 times that of soil
marine effect vs. continental effect
. refers to moderating influences of the ocean and usually occurs in locations along coastlines or on islands
.refers to greater range between maximum and minimum temperatures on both a daily and yearly basis that occurs in areas that are inland from the ocean or distant from other large water bodies
thermal equator
is an isotherm connecting all points of highest mean temp, roughly 27 degrees;it trends southward into the interior of S.A and Africa, indicating high temps over the interior landmasses
the thermal equator shifts northward with high summer sun and reaches the persian gulf-pakistan-iran area.
Verkhoyansk, Siberia
63 degree season temp chage
-most dramatic change
present temperatures are higher then any time during the past ___ thousand year
125
geography defined
study of the evolving character and organizations of the earths surface
-interconnectedness of human and natural phenomena
Regional Geog
looks at places and what makes them unique
- uses boundaries to enclose similar attributes
- is scalable
Systematic Geog
looks at common principles and phenomena -this class fits within this area
4 physical realms of earth
Atmosphere, hydrosphere, lithosphere, biosphere
systems
Systems:
. are structure by pathways along which matter and energy flow
. positive and negative feedbacks determine system behaviour
. behaviour may be highly dynamic or exhibit relative equilibrium
-equilibrium does not mean no change, just becomes a back and forth around a equilibrium
. Positive feedbacks: reinforce or accentuate change
-ex: hurricanes are out of control heat engines running on water vapour
. Negative feedbacks: compensate or reduce change
- Ex: shivering in the human body works to heat you up, sweating does the opposite
. Equilibrium: flow rates in different pathways remain the same
- usually regulated by negative feedbacks
. Time cycles: matter and energy may flow at different rates
- these rates may be subject to cyclical change
earths path around the sun:orbital revolution; an _______ path around sun
each orbit is on the plane of the _____
elliptical
ecliptic
aphelion(Away) ______km on _____(date) – Perihelion (Proximity)______km on _______(date)
152 million km-July 4
147 million km- Jan 3
4 effects from axial rotation of earth
. daily cycle of night and day . Coriolis effect -deflection of wind and flowing water . tides . deformation of the solid earth -flattening of earth at poles -bulging of earth at the equator
Rotation of earth is ____ to ____
west to east (counter clockwise)
Subsolar point is the compliment of the _____
. subsolar point is the compliment of the latitude
-ex: at the equator (0 degrees) the subsolar point is 90 degrees
-ex: at the 40th latitude the subsolar point is 50 degrees
. HAVE TO ADD UP TO 90 DEGREES
Solstices
. SUMMER SOLSTICE: Tropic of Cancer (23.5 degrees north) June 21
. WINTER SOLSTICE: Tropic of Capricorn (23.5 degrees south) December 21
. MAXIMUM POINTS THAT THE SUN REACHES AWAY FROM THE EQUATOR BACK AND FORTH
.it doesn’t matter what latitude you’re at, the angle that the sun is at during the year changes by exactly 47 degrees
Declination
change in angle
.it doesn’t matter what latitude you’re at, the angle that the sun is at during the year changes by exactly 47 degrees
Saskatoon at 52 degrees North when is equinox in September?
Question: What angle is the sun at June solstice: 38 +23.5=
What angle is the sun at December solstice:
Saskatoon at 52 degrees North when is equinox in September?
Answer: 38 degrees
Question: What angle is the sun at June solstice: 38 +23.5= 61.5 degrees
What angle is the sun at December solstice: 38- 23.5= 14.5 degrees
4 types of cartographic techniques
Choropleth Map:
. uses tonal shading that are proportional to the density of phenomena (population density)
Isopleth Map:
. uses a series of lines that connect the same values
Hypsometric Tints:
. uses graduated colours to indicate change (elevation map)
Dot Map:
. uses dots to show the concentration of phenomena in an area, where each dot represents a value
Scale:
. Large scale, _____ area
. Smaller scale, _____ area
. Large scale, smaller area
. Smaller scale, Larger area
Describe UTM
Universal Transverse Mercator (UTM)
. 60 longitudinal zones (1 to 60) starting at 180 degrees west. Zones are 6 degrees wide
. 20 latitudinal zones from 80 degrees south- 84 degrees North denoted by letters C to X, omitting the letters I & O. Each zone is 8 degrees south-north (except X is 12 degrees)
. Areas are references by quoting the longitudinal zone number, followed by the latitudinal zone letter
Ex: southern Saskatchewan is 13U
. Within each longitudinal zone the TM projection is used to give co-ordinates (easting and northiings) in meters
Troposphere Atmospheric Variability (4)
. Several properties of the troposphere are highly variable:
-temperature and lapse rates
-water vapour content
-particulate and aerosol content
-atmospheric pressure and motion
. more water vapour means more energy retention
Rate of energy inflow is about ____ W per square meter (solar constant)
Water vapour can more effectively absorb _______ wavelengths
1370
longer
Insolation can be met with 4 fates when coming to earth
- scattering
- refraction
- reflection
- Absorption= 2/3
Roughly / of the energy is absorbed, most at the surface
2/3
. Heating occurs when net radiation is ______
. cooling when it is _______
. Heating occurs when net radiation is positive
. cooling when it is negative
Barometer
what affects readings
Barometer:
.measures atmospheric pressure
-measurment is dependent on whether the air is moving, wind changes results
Movement of air: Warm and Cooler air and matching pressure
. Warmer air rises due to buoyancy
-rising air can also expand
. cooler air becomes compressed
-sinking air becomes compressed
-upward=lower pressure
-downward= higher pressure
.Horizontal motions occur in response
-these are called winds
-named by direction or origin
what is the main thing that heats the air at the surface? the _______ is primary source of heating and cooling for atmosphere
earth
If there is a SSE wind then which direction is the wind going?
NNW
Isobars
Wind is set in motion by THE _____ ______ FORCE
Isobars: .Lines of equal atmospheric pressure -units in millibars (mb) or kilopascals (kPa) . closely spaced -steep gradient -strong wind . Widely spaced -gentle gradient -light winds
High pressure: Isobars widely spaced (Light winds)
Low Pressure: Isobars are slimly spaced (Strong winds)
Wind is set in motion by THE PRESSURE GRADIENT FORCE
Coriolis effect in the hemispheres and equator
The Coriolis Effect/Force: .Earths rotation influences air motion .creates deflection to the right or left .creation of rotating cells of air flow VIDEO: .All free moving objects are deflected by the Coriolis effect, including air masses -In the North it deflects to the right -In the South it deflects to the left -On the equator there is very little effect - Poles is maximum deflection
PRESSURES INFLUENCING AIR MOTION: 4
PRESSURES INFLUENCING AIR MOTION:
- Resultant wind
- Coriolis Force
- Pressure Gradient
- Friction Force
air pressure
created through motion, size,, and number of the molecules that constitute air
.warmer air is less dense and therefore lighter, than colder air and exerts less pressure
.as water vapour in the air increases density decreases, so humid air exerts less pressure then dry
.warm humid air is associated with low pressure
.cold dry air is associated with high pressure
aneroid barometer
means no liquid used
High pressure approximately ___ mb
Low Pressure approximately ___mb
1050
980
two principle parts of wind
speed and direction
wind speed measured by _______
wind direction determined by _____
anemometer= km/h
WIND VANE- winds named from wwhere they originate
Pressure Gradient Force
. drives air from areas of higher barometric pressure (more dense air) to areas of lower barometric pressure (less dense air) therby causing wind
.a gradient is the rate of change in some property over distance
.caused by the earth bbeing unequally heated
isobar
is an isoline plotted on weather map to connect points of equal pressure
.closer isobars denote steepness in the presure gradient-faster air movement from a higher to lower pressure
low pressure rotates _____ and _____
high pressure rotates _____ and ______
rotates inwards and up
outwards and down
rotational speed of earth is ___ km/h at poles
____ km/h at the equator
0
1675-no coriolis effect at equator
friction force
4 factors affecting it
drags on the wind as it moves accross the earths surfaces but decreases with height above the surface
. without friction, surface winds would simply move in paths paralell to isobars and at high rates of speed
.upper air winds are not affected
.depends on 1.surface texture, 2.wind speed, 3.time of day and year, and 4.atmos conditions
geastrophic winds
winds produced by the combination of coriolis effect and pressure systems: winds that do not flow directly from high to low, but that flow around pressure areas, remaining parallel to isobars
-characterisitic of upper tropospheric circulation
. not possible near the surface because of the friction forces
In the N.hemisphere surface winds spiral out from a high pressure area in a _______ clockwise direction, forming an _______, and spiral into a low-pressure area in a _______ clockwise direction forming a ______
clockwise, anticyclone
counter clockwise, cyclone
In the S.hemisphere surface winds spiral out from a high pressure area in a _______ clockwise direction, forming an _______, and spiral into a low-pressure area in a _______ clockwise direction forming a ______
Counter clockwise, anticyclone
clockwise, cyclone
as air moves away from centres of an anticyclone, it is replaced by ______ air. These high pressure systems are typically characterized by ______ skies.
As surface air flows toward the centres of a cyclone, it converges and moves ______ and this promotes the formation of _____ skies
descending(sinking)
clear
upward
cloudy/stormy weather
three levels of atmos circulation
primary circulation:
. consiting of general worldwide circulation
secondary circulation:
. consiting of migratory high-pressure and low-pressure systems
tertiary circulation:
. including local winds and temporal weather paterns
winds that move principally north or south along meridians of longitude are called _____ _____
winds that move east to west along parallels of latitude are _____ _____
meridional flows
zonal flaws
Four broad primary pressure areas in each hemisphere
1.equatorial low (warm and rainy)
2.polar highs (cold/dry)
.
3.subtropical highs (hot/dry)
4.subpolar lows (cool/wet)
1&2= stimulated by thermal (temp) factors 2&3= formed by dynamic(mechanical) factors
Intertropical convergence zone formed by the _____ _____
equitorial low
Equitorial low
.constant high sun altitude and consitent daylength make large ammounts of energy available in the region throughout the year
-warming creates lighter,less dense, ascending air, with surface winds converging along the entire extent of the lowpressure trough
-extremely moist and full of latent heat energy
-as air rises it expands and cools producing condensation(heavy rainfall)
-forms Intertropical convergence zone
.Trade Winds: winds converging at the equatorial low are called Northeast and southeast trade winds
.hadley cells in each hemisphere that begin with winds rising along the ITCZ
.equitorial calms in the ITCZ are called doldrums
-winds move either north or south from the equator and turn towards the east beginning around 20 N and S
Subtropical Highs
.brings clear, frequently cloudless skies over the sahara and other deserts
.subtropical anticyclones generally form as air above the subtropics is mechanically pushed downward and heats by compression on its descent to the surface
.warmer air has greater capacity to absorb water vapour making this descending warm air relatively dry
-moisture is removed as heavy percipitation at the equitorial portion of the circulation
.known as “calms of cancer and capricorn”
.surface air diverging within the subtropical high-pressure cells generaates earths principal surface winds: the trade winds that flow toward the equator and the westerlies, which are dominant winds flowing from the subtropics toward high latitudes
Horse latitudes
subtropical highs-hot,dry desert air
westerlies
which are dominant winds flowing from the subtropics toward high latitudes
stonger in winter
Subpolar Lows
.dominant in the winter and almost unrelevent in summer with the strengthening of high pressure systems in the subtropics
. the area of contrast between cold air from higher lat and warm air from lower lats forms the POLAR FRONT where masses of air with different characteristics meet
.where warm moist air from the westerlies meets cold, dry air from the polar and arctic regions
. low pressure cyclonic storms migrate out of aleutian and icelandic frontal areas and may produce precipitation in N.A and europe.
polar front
.the area of contrast between cold air from higher lat and warm air from lower lats forms the POLAR FRONT where masses of air with different characteristics meet
.where warm moist air from the westerlies meets cold, dry air from the polar and arctic regions
. warm air is displaced upward above the cool air at this front, leading to condesation and precipitation
Polar Highs
.are weak
. polar atmospheric mass is small, recieving little energy from the sun to put it in motion
. winds move away from the polar region in an anticyclonic direction and descend and diverge clockwise in the N.A(counter clockwise in S.A) and form weak variable winds of the polar easterlies
.Antarctic has the stronger and more persistent high pressure system
Ridges and Troughs upper atmos circulation
ridges: winds slow and converge to create conditions promoting anticyclonic circulation as it pusshes downwards
troughs: winds accelerate and diverge (creates upward draft for cyclones at the surface because it creates an outflow of air aloft that stimulates inflow of air into a low pressure cyclone
Rossby waves
.within the westerly flow of geostrophic winds are great waving undulations
.occur along the polar fronts where colder air meets wasmer air; and brings toungues of cold air southeward with warmer tropical air moving northward
jet streams
. the most prominent movement in the upper level westerly geostrophic wind flows
. irregular concentrated bands of wind occuring at several different locations that influence surface weather systems
.jet streams in each hemisphere tend to weaken during the hemispheres summer
.polar jet stream between 30 degrees and 70 degrees N latitudes at the tropopause along the polar front
.Subtropical jet stream flows near tropopause in subtropical latitudes near the boundary between tropical and midlatitude air (20 to 50 degrees latitude)
Monsoons( think Asian ex)
.seasonally shifting wind systems and involve an annual cycle of returning precipitation with the summer sun
. Asian Monsoon Pattern:
. driven by inequal heating between Asian landmass and the indian ocean-heavily influenced by shifting migration of the ITCZ during the year, which brings moisture laden air northward during the northern hemisphere summer
winter= high pressure cold dry winds
summer= continental interior develops low pressure associated with high temperatures and high pressure system dominates over the indian ocean causing warming of sea surface temp
pressure gradient is reversed in summer compared to winter
- hot subtropical air sweeps over the warm ocean towards india producing high evaporation rates
- producing monsunal rains
High pressure: Isobars widely spaced (____ winds)
Low Pressure: Isobars are slimly spaced (_____winds)
Light or strong winds
light
strong
Local winds: belong in the _____ category of atmos circulation
tertiary
.land and sea breezes
.different heating characterisitics of land and water surfaces create these breezes
-during the day land heats up and rises and marine cool breeze is sucked into fill the space, at night the opposite occurs as cool land air goes to fill the space of rising warm air over the sea
Mountain and Valley breezes
slopes heat up faster then the valleys which makes a low pressure system and results in valley winds blowing up the slope towards the system
Ocean currents are affected by 5 factors
- Wind frictional drag
- Coriolis effect
- density differences caused by temp and salinity
- configuration of continents and ocean floor
- astronomical forces that cause tides
the oceanic circulation systems are known as ____ and generally appear to to be offset towards the _____ side of each ocean basin. Remember in the N. Hem winds and ocean currents move _____ about high pressure cells; S. Hem circulation is ______
gyres, west
clockwise
counterclockwise
Equtorial Currents
Trade winds drive the ocean surface waters westward in a concentrated channel along the equator
upwelling current
where surface water is swept away from a coast either by surface divergence(Coriolis) or by offshore winds
.cool water generally rich in nutrients and rises from great depths to replace vacating water
downwelling current
with an accumulation of water such as the western end of an equatorial current or in the labrador sea, or along the margins of anarctica- the excess water gravitates downward
-deep currents that flow vertically and along the ocean floor and travel the full extent of the ocean basins redistributing heat energy and salinity over the globe
thermohaline circulation
deep ocean currents
-slower then wind driven currents, driven by temp and salinity
El Nino
southern oscillation
.in the pacific ocean forces the greates interannual variability of temperature and precipitation on a global scale
.pressure patterns and surface temp shift from their usual locations in the pacific
.higher pressure then normal develops over the western pacific and lower pressure develops over the eastern pacific
.shifting of atmos pressure and wind pattern from westerlies to easterlies is the southern oscillation
.results in a warm pool of water at the surface across the pacific and change in wind direction
3 to 5 years or 2 to 12 years
La Nina
ENSO’s cool phase
. when surface waters in the central and eastern pacific cool o below normal by 0.4 celcius or more
-usually weaker then El Nino and amost counteracts warmed water
oceanic circulation primary influence is _____
wind
gyres
Gyres:
. large circular currents
. subtropical gyre corresponds to subtropical high pressure
Oxygen is the ____ side and Hydrogen is the ____ side
Both work together to attract the opposite creating the polarity of water molecules
creates surface tension
negative, positive
capillarity
towel draws water because hydrogen bonds make each molecule pull on its neighbor
condensation
is the process through which water vapour in the air become liquid water
- forms clouds
- energy released
evaporation
liquid water becomes water vapour
-energy absorbed
deposition
is the process through which water vapour attaches directly to an ice crystal, leading to the formation of frost
-energy released
sublimation
is the process by which ice changes directly to water vapour
-energy absorbed
water is at its greatest density at __ degrees celius
4
when water is in the process of freezing its _____ increases and its _____ decreases
volume
density
the heat energy of a phase change is called ____ heat
latent
for water sensible temp stays the same
Ice to liquid water = __ calories of latent heat
0 degree water to 100 degree water= __ calories
100 degree water to water vapour= __ calories
80
100
540
Relative Humidity
a ratio expressed as percentage of the amount of water vapour that is actually present compared to the maximum that could be present in the air at a given temp
.tells us how close the air is to saturation
dew-point temp
the temperature at which a given sample if vapour containing air becomes saturated and net condensation begins to form water droplets
Two ways to express humidity
- Vapour pressure
- as free water molecules evaporate from surfaces into the atmos, they become water vapour
- the share of air pressure that is made up of water vapour molecules is vapour pressure expressed in mb - Specific Humidity
- is the mass of water vapour(in grams) per mass of air (in kg) at any specified temp.
- not affected by changes in temp or pressure
- useful in describing the moisture content of large air masses that are interacting in a weather system
two tools for telling humidity
Hair Hygrometer
-uses the principle that human hair changes as much as 4% in length between 0 and 100% humidity
sling psychrometer
- two thermometers mounted side by side
- one dry bulb thermometer which records ambient(surround) air temp and one wet-bulb thermometer which is covered in a moistened cloth wick
- tells you how dry/wet air is
Two opposing forces decide the vertical position of a parcel of air:
- upward Buoyancy
- downward gravity
.a parcel that is lower density then the surrounding air rises and expands as external pressure decreases
.higher density parcel descends under the force of gravity and compresses as external pressures increase
______ of a volume of air determines its density
temp
buoyancy depends on ________ and it depends on ________
density
temp
diabatic vs adiabatic
Diabatic= occurring with an exchange of heat
adiabatic= occurring without a loss or gain of heat, that is without any heat exchange between surrounding environment and the air parcel
Moist Adiabatic rate is _ C x 1000m
Dry Adiabatic rate is _ C x 1000m
6
10
Elevation found at and description
Stratus
Cumulus
Cirrus
Altostratus
cumulonimbus
up to 2000 m: uniform, featureless, gray clouds that look like high fog
near surface to 13000 m: sharply outlines, puffy, flat based clouds with swelling tops associated with fair weather
6000-13000m: wispy, feathery, streaks or plumes
2000-6000m: thin to thick clouds, suns outline just visible through clouds on gray day
near surface to 13000 m:towering giant, rainstorm thundercloud, anvil shaped top
clouds have three basic forms
flat, puffy, and wispy
3 Types of fog:
- Radiation Fog
- when radiative cooling of surface chills the air layer directly above that surface to the dew point temp, creating saturated conditions - Rime Fog
- consists mostly of tiny supercooled droplets that turn into rime frost on contact with freezing objects
- common in cold weather
- aircrafts must deice before takeoff - Ice-crystal Fog
- at low temps in continental artic air mass, ice crystal fog may develop, for example when the air becomes full of ice crystals that formed with sublimation - Advection Fog
- when air in one place migrates to another place where conditions are right for saturation
- ex: when warm moist air moves over cooler ocean currents, lake surfaces, or snow masses, the layer of migrating air directly above the surface is chilled to the dew point - Evaporation(steam) Fog
- related to both advection and evaporation forms when cold air lies over warm water
- is a shipping hazard called sea smoke
4 Main air masses affecting N.A
- Continental Polar (cP)
. for only in the northern hemisphere and are most developed in winter and cold weather conditions
. major players in middle and high latitude weather as their cold, dense air displaces moist, warm air in their path lifting and cooling the warm air and causing its vapour to condens
.cold stables air, clear skies, high pressure, and anticylonic wind flow
.S. Hemisphere lacks land mass to have a similar air mass - Maritime Polar(mP)-one on each northern coast
.air masses in N. hemisphere sit over the northern oceans
.within them is cool, moist, unstable conditions throughout the year
. Aleutian and Icelandic subpolar lows lie within the mPs - Martitime Tropical(mT)-one at southwest N.A one southeast
.mT gulf/atlantic air mass is particularly unstable and has more moisture and available energy
.as a result the western united states, affected by the weaker of the two mTs receives lowe average precipitation then the rest of the country
-warm, humid - Continental Arctic(cA)surrounded by cP
- very cold, dry, stable
Four principal mechanisms lifting mechanisms for an airmass
- Convergent: results when air flows toward an area of low pressure
- Convectional: when air is stimulated by local surface heating
- Orographic:occurs when air is forced over a barrier such as a mountain range
- Frontal Lifting: as air is displaced upward along the leading edges of contrasting air masses
chinook winds
are the warm downslope air flows characteristic of the leeward side of mountains
. can bring 20 degree C jump in temp
cold front vs warm front
.the steep face of an advancing col air mass reflects the ground hugging nature of cold air, caused by greater density and more uniform characteristics compared to warmer air mass it displaced upwards
squall line
a sudden episode of high winds that is generally associated with bands of thunderstorms
warm front
warm air masses can be carried by jet stream into regions with colder air such as when an air flow called “pineapple express” carries warm moist air from Hawaii and the pacific coast to north America
.the leading edge of an advancing warm air mass is unable to displace cold air upwards so instead the warm advances wedging itself on top of the cold air mass
midlatitude/wave cyclone created by contrasting ____ _____
explain them
air masses
.are migrating low-pressure systems that occur in the midlats outside the tropics
. low pressure centre with converging, ascending air spiraling inwards counter clockwise in N.H and inward clockwise in S.H
.storm tracks move with the seasons, farther N in summer and S in winter
Last about 3-10 days
4 stages of midlat cyclone
Generally Travel west to east
- Cyclogenisis: atmospheric process in which low pressure wave cyclones develop and strengthen
- usually begins at the polar front where cold and warm air masses converge and are drawn into conflict crating unstable conditions - Open Stage:to the east of the developing low pressure centre of a N.H cyclone, warm air begins to move northward along an advancing front while cold air advances southward to the west of centre
- Occluded stage: when the colder cP air mass is denser then warmer mT air mass the cooler, more unified air mass acting like a bulldozer moves faster then the warm and overtakes it and wedges beneath it created an occluded front.
- turns into a stationary front until one front becomes dominant and the whole thing becomes a warm or cold front - Dissolving stage: occurs when its lifting mechanisms is completely cut off from the warm air mass, which was its source of energy and moisture
Synoptic analysis
is the evaluation of weather data collected at a specific time
weather related damage has risen by ___% in three decades
500
mesocyclone
deep, persistently rotating updraft
. a spinning cyclonic rising column of air associated with a convective storm: thunder/supercell
-produce heavy rain, large hail, lightning, possibly tornado acitivity
Tropical Cyclones
. originate within tropical air masses
. are powerful manifestations of the earth-atmos energy budget
.classified according to wind speed; the most powerful being hurricanes(NA), typhoons(Western Pacific), or cyclones(Indonesia) which are different regional names for the same type of storm
.wind speeds greater then 119 km/h
a fully fledged hurricane, typhoon or cyclone has wind speeds of atlest ___ km/h
119
Why are cyclone in tropics different then those in midlats
what triggers a tropical cyclone?
. air of the tropics is essentially homogenous with no front or conflicting air masses of differing temps
. warm air and warm seas ensure abundant water vapour and thus the necessary heat to fuel the storms
.convert heat energy from the ocean into mechanical energy in the wind-the warmer the ocean and atmos, the more intense the conversion and powerful the storm
what triggers it:
.cyclonic motion begins with slow moving easterly waves of low pressure in the trade wind belt of the tropics
. if sea-surface temp exceeds 26 degrees a tropical cyclone may form on the eastern sides (leeward) sides of one of the troughs of low pressure
Tropical Cyclone Classification 4
- Tropical Disturbance
- Tropical Depression
- Tropical Storm
- Hurricane
there are _ categories for hurricanes
this scale is called _____-_____ wind scale
5
saffir-simpson
World oceans __% of water , __% not in oceans(__% ice and glaciers, __% Ground Water, __% accessible water)
World oceans 97 , 3% not in oceans(2.1% ice and glaciers, 0.63% Ground Water, 0.02% accessible water)
Precipitation=_____+_____
evaporation+runoff
2 Empirical(numerically based) climate classification approaches- Know that these are empiracal in nature for midterm
1.koppen-greiger system
. uses mean monthly temp and precipitation data
. five climate regions (macroclimate)
-letter coded (A,B,C,D,E)
-4 Based on temp criteria
- 1 based on moisture in relation to temperature
.highland areas excluded
A= tropical rainy climates
-all monthly means > 18 degrees C
C= mild humid climates
-1 or more monthly means < 18 degrees, but >-3 degrees and atleast one is >10 degrees
D= snowy forest climates
- Warmest month mean >10 degrees
- Coolest month mean means annual precipitation
- Varying formulae depending on seasonal precipitation patterns
. additional codes for climate types
2.Thornthwaite water balance system
. Thornthwaite classification . Based on soil moisture regimes . Water budgets -storage in soil pore spaces -withdrawal and recharge -surpluses and deficits Soil water budget: . the interrelationship between -precipitation -water need (potential evapotranspiration) - water use (actual evapotranspiration) - storage in soil water zone/compartment . soil water balance in a soil column . surplus = RUNOFF
