Exam 1 Study Guide - Introduction to Physical Geography | GEOG 1111, Study notes of Geography

Download Exam 1 Study Guide - Introduction to Physical Geography | GEOG 1111 and more Study notes Geography in PDF only on Docsity! Geog1111 May 14, 2013 [Intro and Chapter 1]  Warm ocean current along the east coast is the Gulf Stream o The Gulf Stream and the North Atlantic Drift is why London never receives snow.  Storms come off pacific and move across the continent o Carried by mid latitude westerly winds  Winds always flow from west to east  Mid-latitude Westerly Winds cross over the north Atlantic. o Water of N. Atlantic is 40 degrees Fahrenheit. o The wind picks up the warm air from water and carries it to London. o The is called North Atlantic Drift  1300 years ago, the North Atlantic Drift stopped, which caused the Ice Age  Colorado wildfires 2012 o Serve drought caused the fast spread of the wildfires o The topography, winds, the sun, etc. increased the fires o Air rises up the mountain valley which brings the fire oxygen o Also the clear cutting for timber and fire suppression (undergrowth); and pine bark beetles [it kills pines which increases the amount of dead trees which is kindling] o Low snow pack means that the following summer will be drier and hotter  Geographers are interested in understanding processes and patterns that happen on the surface of the earth  Geographers use spatial analysis; everything is connected to the things around it o Use an Earth systems science approach o Study how all the variables connect over space  Geographic Continuum o Left side is Physical and Life---Right side is Human and Life  Physical Geography is the spatial analysis of all the physical elements and processes that make up the environment  Four major spheres: Hydrosphere, Atmosphere, Biosphere and Lithosphere  Thunder Heads lead to summer storms  Conditions in the tropical pacific is the largest predictor of Southern conditions  Ice has a really high albedo [which has to do with heat absorption]  From the Gulf of California to North of San. Fran, is on a different plate that Georgia  Sea ice and its importance in the Artic Basin  Anasazi: o Ancient pueblo people that disappeared o The area was a lot drier, so climate change might have lead to their movement  Rupert is the Cat. Will be tested on him.  Also likes the Toronto Maple Leaves. 4-1 lead with 8 minutes to go. Would have played Ottawa  Chapter 1 is about Earth Systems  Open Systems o Open to input and open to output o A car is an open system. Input fuels, outputs heat, waste, etc. o The car holds the energy and material conversions o The earth is an open system o 99.99% of energy on Earth is based on energy from the sun (input) o The output is the energy from earth that goes back to space o If there were more energy leaving the earth that is coming, the earth would get colder. [Opposite for the other direction] o Open in terms of energy; not for matter [closed for matter] o Photosynthesis and Respiration are open systems  Input for photosynthesis: sunlight, carbon dioxide, water  Output: O2 and CH2O and H2O  System Feedbacks o Albedo is the portion of visible light that is visible on the surface of the earth o Sea ice, snow, & glaciers have high albedo o System feedback describes what happens as you reduce ice  The area exposed has lower albedo, so it absorbs more solar radiation, it gets warmers, reduces ice  Reducing sea ice leads to elevated temperatures  System Equilibrium o Describes fluctuations around a steady state mean o Dynamic equilibrium is when the system fluctuates around a stable average, but there is a trend; like increasing system operations o A near instantaneous shift where the system gets re-centered is what they are afraid of  These are thresholds [aka tipping point or non-linear response] also, think of the canoe parallel  Sea ice contracts in summer, expands in winter time  The four spheres are all interconnected  The Earth is known as an oblate ellipsoid, which means it is slightly flattened at poles, and slight bulge at the equator.  Latitude is 0o to 900 (top at poles). o Also known as parallels o Angle of latitude is 490 o Border between US and Canada is the 49th parallel o 66.50 is the artic circle either N or S o North from equator is the tropics [cancer 23.5o N]  Longitude o Known as meridians o The position of the Prime Meridian is arbitrary [not the equator] o 60o is the angle of longitude o 1800 away from Prime Meridian takes you to the international date line o angular direction E or W of the Prime Meridian o measured in degrees, minutes, seconds  Distance between lines of latitude never change, however lines of longitude change  We have time based upon Standard Time Zones  The sun emits Electromagnetic Radiation [EM] o Joule=standard unit of energy o Watt=rate of energy flow [W= 1J/s]  Remember Kinetic and Potential energy  Methods of energy transfer o Conduction: molecule to molecule transfer  Heat flow; warm to cold  The molecules begin to vibrate in the skillet because they are heated  The energy geos all the way up the handle o Convection: transferred by vertical movement  e.g. boiling water  Keep in mind that the atmosphere is a fluid, so the behavior is modeled like a fluid; you heat the atmosphere and it moves in vertical movement o Radiation is propagated without a medium  All mater emits radiation [waves]  [Well all mater that is above absolute zero, but there is nothing in the natural world that will reach that; not even produced in lab]  Absolute zero in Celsius is -273O; we have yet to reached it  Radiation travels at the speed of light  Radiation [continued] o Quantity= Amplitude o Quality= wavelengths o The shorter the wavelengths, the more intense the energy, e.g. X-Rays o Slightly longer than red is infrared  Electromagnetic Spectrum: all radiation fits on it o Radiant energy emitted by Sun:  7% gamma, X-Ray, UV [high energy]  47% visible  46% infrared o Radio to Gamma [longest to shortest wavelengths] o X-Rays tell us bone density; it moves through the body, and gets bounced back to the sensor. It doesn’t show soft tissue, because it isn’t dense enough.  Predator [The Movie] o Arnold Schwarzenegger leads a team in the jungle to find an alien o About drugs and leftist guerrillas in South America o The alien predator does not use the visible portion to see the world, it uses thermal infrared [the energy being emitted in slightly longer wavelengths] o Arnold covered himself in mud because it would drop the body’s temperature [the infrared being exposed] so the predator could not see him. o Jessie Ventura and Apollo Creed are also in the movies  This is important because [like the wolves in Day After Tomorrow] because they are governors of states now. [Jessie Minnesota]  SARS is a respiratory disease that killed people. o People would move through thermal imaging t see if they had high body temperatures to check to see if they carried SARS  Energy Emission Related to Temperature o Total energy any object emits is a f(x) of temperature o We all emit roughly the same amount of energy o Peak wavelength of earth is 10 microns o Look at the rest of that slide  Insolation: Incoming solar radiation o Input: solar radiation to Earth; concentrated in shorted wavelengths ultraviolet visible and shortwave infrared o Output: earth’s infrared emission to space; longer wavelengths: thermal infrared  Kelvin is the scale used to report temperature that has no negative values o Absolute 0= -273 degrees Celsius and 0 kelvin o Earth’s average is 15 degrees Celsius and 288 K [or 300 K] o Sun is equal to 6,000 K  Curvature of the Earth o Sphericity: reason for unequal receipt of insolation from equator to poles o Where the sun hits a 90O angle, the more energy that is absorbed o The suns rays hit the equator more directly year-round o The point at the surface where it hits 90O called the subsolar point  The annual amount of insolation decreases poleward from Equator o The subsolar point moves northward in June o In June and July, the N. Pole receives more energy than we do o The energy incident does not change at the equator year round  Global Net Radiation is the difference between incoming radiation (insolation) and out-going long wave radiation o Highest surplus over the equatorial and tropical regions  It redistributes the energy north and sourh  The reasons for seasons is the tilt of the axis o Winter and summer solstice and the fall and spring equinox o Winter is when the N. Hemisphere is pointing away the sun o Summer, the N. Pole is pointing towards the sun o Tropic of Capricorn (S.) is when it hits at 90O in the winter o Tropic of Cancer is the subsolar point in the summer o Sun’s rays (position of subsolar points) moves up and down between Cancer and Capricorn  Without tilts, no seasonal changes would happen  24 hours of daylight happens in the Artic Circle on June 21st o Antarctica is dark o Opposite on December 21st  Start of Chapter 3 after this…  The atmosphere acts as a membrane; protects organic life from harmful UV radiation  Exosphere extends to 32,000 km from the top of the atmosphere  Three criteria to examine o Composition o Temperature o Function  Earth exerts a gravitational pull on the atmosphere o The density of the atmosphere decreases higher up [molecules are further apart]  Troposphere is the lowest part of the atmosphere [TSMT]  Average sea level pressure is the pressure the atmosphere exerts of a square meter [1kg/m2, 1013.2 mb, 101.32 kPa]  Clear skies are during high pressure. o This is because the atmosphere is sinking; rising air-cools. o Sinking air is clear because it is sinking towards earth’s surface and condensation doesn’t form  There are 4 layers of the atmosphere when broken down by temperature o Troposphere; where weather is o As you move away from earth, temperatures decrease while moving through the troposphere. o In stratosphere, temperatures increase  Know composition of Atmosphere o 78% nitrogen o 21% oxygen o these to make up 99% o other important: argon.  Also important are green house gasses:  Water vapor  CO2  methane o For first time in 2 million years, CO2 concentration are above 400 parts per million  Temperature in Atmosphere o Slight gradient as to where the troposphere ends depending on where you are o Tropopause is where you fly [between troposphere and stratosphere]  Stratosphere is more stable  Tropopause is -57 C o Normal lapse rate is 6.4 C/1000m o Stratosphere is next layer up  Temp. increases because the ozone layer absorbs heat from the sun (ultraviolet) which leaves visible light and longer wavelengths o Mesosphere continues to get colder [-90 C] called the mesopause o Thermosphere is when the temperature increases again [around 300 F]  Freezes up there because of the decrease in density  Temperature measures the vibration [kinetic movement of molecules].  Temperature is very different than heat  Energy is transferred by molecule to molecule contact  The low pressure cause the molecules to be far apart  Pressure high; molecules close together  Troposphere:  Albedo and reflection: o Albedo is the reflective quality of a surface  The higher the albedo, the higher the reflectivity  The lower the albedo, the higher the absorbency o Fresh snow: 95% o Pavement: 5-10% o Water bodies: 10-60%  Oblique angle will absorb  Direct angle will reflect [look this up] o Earths average albedo is 31%; this mean 31% is reflected back into space  Clouds= 21%  Ground= 3%  Atmospheric gases and dust= 7%  Clouds and Albedo: o Cloud albedo forcing= reflect insolation [increase albedo] it cools the surface; reflects shortwave energy back to space o Cloud greenhouse forcing= trap longwave; heat surface  Absorption: 69% of insolation is absorbed o Converted into infrared radiation or chemical energy o Emit longwave radiation  Input of energy must match the output of the energy [remember, it is an open system] o If the input is larger than outputs, the earth will get warmer  A greenhouse works by trapping heat, so it gets warmer o The light gets trapped because energy gets into the room, molecules vibrate and cannot escape o It enters as shortwave radiation from the sun, it moves through the window, hits whatever is in the space, the objects absorb the energy; the objects emit longwave radiation o Longwave radiation cannot pass through windows, so the heat stays in the room  Stratus clouds are low lying clouds o Thick low lying clouds are affective at scattering shortwave radiation, bounced back into space o Net albedo forcing  Cirrus clouds are high, wispy clods o Trap long wave radiation that emanate from Earth’s surface o Poor at intercepting shortwave radiation  Net greenhouse forcing  Looking at the the figure that has a lot of stuff [Earth-Atmosphere Radiation Balance; fig 4.13] o Left=shortwave o Right=longwave o Ozone absorbs 3 units/100 energy o Energy from the sun interacts with clouds (3 units) o Atmospheric Gases and dust is very affective [18 units]  18+3= 21; atmospheric heat input that is now longwave o 25 units is direct absorption of the ground  end up with 45 units of shortwave unit is now longwave o 45+21=66 units that have to be converted back o Latent heat transfer: evaporation of water, turned into gas or vapor in the atmosphere o Green house makes 110 units leave the earth  Energy gets reemission o 66 units of energy that are emitted back into space [longwave] o Never going to ask units, but will ask what the 3 units that make up Earth’s albedo  Incoming energy gain, exceeds outgoing energy loss o Between the tropics there is an energy surplus o 36O N/S is where the deficit starts  The job of atmosphere and oceans is to take excess energy from the equator and take it to the higher latitudes  Energy balance at Earth’s surface o Hottest time of the day is 2-4pm o Coolest time of the day is right after the sun peaks above the horizon o 6 am is coder than 2 am because there is no insolation, energy is only leaving  Longwave radiation is leaving  No input, only output o The moment the sun cracks the horizon, the input begins again o The earth continues to absorb a lot of energy until 2pm, the rays begin to go oblique o This same phenomenon explains the seasonal lag in heat [summer solstice is June 21st, but hottest part is August]  Simplified surface energy balance: o +SW= insolation [shortwave coming] o –SW= reflection [shortwave leaving] o +LW= infrared o –LW= infrared  IN the tropics there are lower amounts of Net Radiation because lots of energy comes in, but a lot of energy also goes out due to lack of clouds o The lack of clouds means that there is nothing to trap the emitting longwave radiation  Latent heat is evaporation; energy leaving earths surface in association to the evaporation of water o This is so important because energy is moved away from Earth’s surface o Greatest amount of latent heat is around the Gulf Stream and around Japan [Japan current, identical to the gulf stream]  Both on East coast of a continent  West coast of N. America there is a cold water current, along with W. coast of Africa o Also high in the tropics and equatorial regions  These areas have in common very warm water  Easier to evaporate warm water rather than cold water o Very little latent heat transfer over land due to lack of water  Sensible heat is the heat you can sense; the heat you feel while walking on the beach o Centered on the tropics  The Urban Environment Factors; 1. Material 2. Geometric shape 3. Human activity 4. Impermeable surface 5. Pollution o There is essentially a dome if dust o The wind gets tunneled because of “urban canyons” Start of Chapter 5  Temperature is the measure of average kinetic energy  Heat is a form of energy that flows along a gradient  Room temperature is about 21O Celsius  Won’t ask to convert  Water boils at 100 degrees Celsius  Latitude affects insolation o Temperature does not vary is Bahia (Salvador) Brazil, 13 degrees S latitude, 9m elevation  Close to the equator; has more sunlight, no variability in the sunlight o In New Orleans it is warmest in the Summer because the subsolar point is at the tropic of cancer (23.5 degrees) o Scotland does not vary much because it is close to the Gulf Stream  Altitude will affect temperature too. o Denver will always be colder than a city that is in the foothills  Amount of water present is big on temperature too o When energy hits terrestrial surface, and there is no moisture available, it goes to heating the surface [it is opaque] o Water takes a lot of energy to heat up o If landlocked, and far from water, there will be much more extreme temperatures  Earth’s temperature patterns o Thermal equator: the warmest part on the surface of the earth [January] o Isotherms are the temperature lines on the map o Thermal equator is closer to the tropic of Capricorn in January o Thermal equator moves northward [towards Tropic of Cancer] in July o Obviously, the hemispheres flip between July and January  Wind chill: correlates cold and wind speed  Heat index: correlates heat and humidity