GG101 Notes PDF

Preview

Summary

Hamilton...

Description

GG101 Final Notes Chapter 1:  Spatial – refers to the nature and character of physical space, its measurement and the distribution of things within it Open system – transfers energy and matter with surroundings, you put something in and get something out Closed system –doesn’t exchange energy or matter with surroundings, self-contained System feedback – the outputs that influence the way a system operates  Change one variable  reaction that increases or decreases initial variable  Temperature rises  ice melts  ocean absorbs more  more melting  If feedback discourages change in system then it is negative feedback  If feedback encourages change in system then it is positive feedback Equilibrium  Steady state – inputs and outputs are equal, energy and matter constant  Dynamic state – changing trend over time, gradual Threshold – the tipping point where a system can no longer maintain its character so it lurches to a new operational level Abiotic = non-living, biotic = living Earths Four Spheres 1. Atmosphere – thin, gaseous veil surrounding earth, held to the planet by the force of gravity. Formed by gases arising within the earths curst and interior and the exhalations of living things on earth. Combination of nitrogen, oxygen, argon, carbon dioxide, water vapor and trace gases 2. Hydrosphere – earths waters exist in the atmosphere, on the surface, and in the curst near the surface and collectively form the hydrosphere. The cryosphere is the portion of the hydrosphere that is frozen 3. Lithosphere – earth’s crust and a portion of the upper mantle directly beneath the crust form the lithosphere. There is an uneven distribution of heat energy and pressure on this level 4. Biosphere – are in which physical and chemical factors form the context of life. The biosphere exists in the overlap of the three abiotic spheres and evolves, reorganizes, undergoes extinction and manages to flourish

Latitude + Longitude: Latitude – an angular distance north or south of the equator measured from the center of the earth (0-3600) Parallel – a line connecting all points along the same latitudinal angle, lines that run east and west, parallel to the equator, does not cross over or converge, intersect meridians at right angles Longitude – an angular distance east or west of a point on the earth’s surface measured from the center of the earth (1-1800) Meridian – a line connecting all the points along the same longitude, lines that run north and south If standing on 900 latitudes, there is no east and west. Only two points like this are 900 North and 900 South where you are facing either North or South at all times Prime meridian – a meridian designated as 0 degrees, runs N-S connecting poles, ½ of great circle, spaced farthest apart at equator, lines runs E or W of the prime meridian Great circle – a plane on our surface that intersects our globe, dividing it into two halves and passes through its center Small circles – a plane that intersects the globe along a small circle, splits the globe into unequal sections, this plan does not pass through the center of the globe Geodesy – a measurement of shape of earth – sphere, slight equatorial bulging because spinning of earth

Global Time: Greenwich Mean Time (GMT) – official standard for world time zone, prime meridian set in Greenwich, England 60’ (minutes), 10, 60” (seconds) 1-hour spans 7.50 on either side of these central meridians Longitude runs from: 00 to 1800 E or W Latitude runs from: 00 to 900 N or S Coordinated Universal Time (UTC) – legal reference for official time in all countries, based on average time calculations from atomic clocks collected worldwide International Date Line (IDL) – 1800 meridian on the opposite side of the planet, marks the place where each day officially begins at 12:01 A.M, new day sweeps westward causes by earth’s eastward turning on its axis, west side is always a day ahead of east side Daylight Saving Time – setting time ahead 1 hour in the spring and back 1 hour in the fall

Scale of Maps + Map Projections Cartography – the science and art of map making Map – generalized view of an area, as seen from above and reduced in size Scale – the ratio of the image on a map to the real world  Written ratio, fraction or graphically  1:250,000 = 1cm on map is 250,000cm on ground  Large scale map = low detail  Small scale map = high detail

Projection – process of transforming spherical Earth to flat map Standard parallel/standard meridian – a standard line true to scale along its entire length without any distortion Mercator projection – a cylindrical projection with meridians appearing as equally spaced straight lines and parallels appearing as straight lines that are spaced closer together near the equator, these maps present false notions of size Rhumb line – line of constant direction that is straight and therefore facilitates plotting directions between two points Global Positioning System (GPS) – system comprised of at least 27 orbiting satellites, in 6 orbital planes that transmit navigational signals to earth-bound receivers

Chapter 2: Milky Way Galaxy – a flattened, disk shaped collection of stars in the form of a barrel spiral – a spiral with a slightly barred or elongated core Gravity – the mutual attraction exerted by every object upon all other objects in proportion to their mass Planetesimal hypothesis – how suns condense from nebular clouds (nebula = large, slowly rotating and collapsing cloud of dust and gas) Speed of light – roughly 300,000km/s-1 (299,792) or about 9.5 trillion km per year, which is captured by the term light-year Perihelion – earth’s closest position to the sun, which occurs on January 3rd during the northern hemispheres winter Aphelion – earth’s farthest position from the sun, which occurs on July 4th during the northern hemispheres summer Sun is located in the middle of our solar system, but it is not centered, it is slightly offset to one side, which is the cause of perihelion and aphelion Fusion – the suns abundant hydrogen nuclei are joined together due to high temperatures and deep pressure forming helium Sunspots – surface disturbances on the sun causes by magnetic storms that appear as dark spots, a solar minimum is a period of years with few sunspots visible and a Solar flares – magnetic storms that cause surface explosions Solar wind – movement of these outburst in space Aurora Australis – Northern lights, caused from coronal mass ejections from the sun

Aurora Borealis – Southern lights, caused from coronal mass ejections from the sun Corona – suns rim Magnetosphere – surrounds earth and extends beyond atmosphere, deflects the solar wind toward both of earths poles so that only a small portion enter upper atmosphere, generated by dynamo-like motions within our planet Coronal Mass Ejections (CME’s) – massive outbursts of charged material, aimed towards earth and often cause auroras in the upper atmosphere near the poles, which is referred to as the northern and southern lights Electromagnetic spectrum – spectrum of all possible wavelengths of electromagnetic energy, all traveling away from the sun at the same time, energy is different at the top of our atmosphere then at the surface at earth, we receive everything on the right side of visible light on the spectrum at the surface of Earth, left of visible light is referred to as shortwave length while right side of visible light is referred to as long wave Wavelength – distance between corresponding points on any two successive waves, distance from crest to crest or trough to trough Frequency – time it takes for successive waves to pass a fixed point, unit of time The sun emits radiant energy comprised of 8% ultraviolet, X-ray and gamma ray wavelengths (shortest wavelength); 47% visible light wavelengths and 45% infrared wavelengths (longest wavelength) Sun is hotter so radiates shorter wave energy, mainly visible and near infrared, Earth is cooler so it radiates longer wave energy, mainly thermal infrared High frequency is associated with small wavelengths and high energy High energy (or short wave radiation) is associated with higher temperature Low energy (or long wave radiation) is associated with lower temperature Blackbody radiator – a perfect absorber of radiant energy, it absorbs and subsequently emits all the radiant energy that it receives Thermopause – region at the top of the atmosphere, roughly 480km above the earth’s surface Insolation – solar radiation that reaches a horizontal plane at earth, incoming solar radiation  Insolation at the top of the atmosphere is expressed as the solar constant (1372W/m2)  Tropics receive more concentrated insolation (energy per unit area) due to the Earths curvature, tropics receive 2.5 times more the amount than the poles receive

Solar constant – the average insolation received at the thermopause when earth is at its average distance from the sun, a value of 1362W/m-2 Subsolar point – location where insolation is perpendicular to the surface Net radiation – the balance between incoming shortwave energy from the sun and all outgoing radiation from earth and the atmosphere, energy inputs minus energy outputs, not the same rays being reflected but rather different wave lengths 3 types of light – short wave, long wave and visible light Length of days on Earth – poles experience total darkness at some points in the year, equator experiences 12 hours of day and 12 hours of night every day, poles have greatest variation whereas equator has the least Seasonality – the seasonal variation of the sun’s position above the horizon and to changing day lengths during the year, seasonal variation is a response to the change in the sun’s altitude or angle between the horizon and the sun Reasons for Seasons – Revolution (Earth moving around the sun), rotation (spinning of Earth), tilt of Earth’s axis, Axial parallelism, Sphericity Declination – the latitude of the sub solar point Revolution – earth’s travel around the sun Rotation – earth’s spinning on its axis Tilt – alignment of axis at about a 23.50 angle from perpendicular to the plane of the ecliptic (plane of the earth’s orbit) Axial Parallelism – unchanging axial alignment, with Polaris directly overhead at the North Pole throughout the year Sphericity – oblate spheroidal shape lit by sun’s parallel rays, the geoid Linear velocity of rotation at any point on earth’s surface varies dramatically with latitude; at the poles the velocity is 0 Plane of the ecliptic – a plane touching all points of earth’s orbit Tropic of Cancer – suns declination at its farthest point north Tropic of Capricorn – suns declination at its farthest point south Equinox - equal hours of day and light

December solstice – northern hemisphere winter The circle of illumination excludes the North Pole region from sunlight but includes the South Pole region. The Subsolar point is about 23.50 S latitude, the Tropic of Capricorn parallel. The Northern Hemisphere is tilted away from these more direct rays of sunlight-our northern winter-thereby creating a lower angle for the incoming solar rays and thus a more diffuse pattern of insolation Annual March of the Seasons – Winter solstice (December 21 or 22, sub solar point at Southern Tropic), Spring equinox (March 20 or 21, subsolar point at Equator), Summer solstice (June 20 or 21, subsolar point at Northern Tropic), Fall Equinox (September 22 or 23, Subsolar point at Equator) March equinox – the circle of illumination passes through both poles, so that all locations on earth experience a 12-hour day and a 12-hour night June solstice – Subsolar point migrates from the equator to 23.50 N latitude, the Tropic of Cancer September equinox – all parts of the globe experience a 12 hour day and a 12 hour night; the subsolar point returns to the equator, with days growing shorter to the north and longer to the south

Chapter 3: Normal Lapse Rate – average temperature decrease with a raise in altitude, 6.4C 0 per km, it is C0 because it refers to a range of temperatures, change of 60 Environmental Lapse Rate – actual lapse rate, can vary depending on weather, measured at a place at a specific time Atmospheric temperature varies greatly depending on temperature and by composition By Temperature: Troposphere – surface to 18km, final layer encountered by incoming solar radiation, supports life, the biosphere and is the region of principal weather activity, roughly 90% of total mass of the atmosphere and the bulk of all water vapours, average temperature of -570C Stratosphere – extends from about 18km to 50km above Earth’s surface, temperatures increase with altitude from -570C at 18km to 00C at 50km, the stratospheres outer boundary is called the stratopause and is the location of the ozone layer, temperature increases with altitude because of the absorbtion of ultraviolet radiation Mesosphere – area from 50km to 80km above earth and is within homosphere, coldest portion of atmosphere at -900C, contains noctilucent clouds, temperature decreases with altitude

Thermosphere – “heat sphere”, roughly corresponds to the heterosphere, from 80km out to 480km out, upper limit of the thermosphere is the thermopause, thermopause may lower in altitude from 480km to 250km or may raise to 550km, temperatures rise sharply in the thermosphere to 12000 and higher, high temperatures in the thermosphere excite molecules to vibration creating kinetic energy which we can then measure to find temperature, would feel cold to our bodies due to not enough molecules to transfer heat to our skin Heat – the flow of kinetic energy from one body to another resulting from a temperature difference between them Noctilucent clouds – tenuous cloud-like phenomena that are the "ragged edge" of a much brighter and pervasive polar cloud layer called polar mesospheric clouds in the upper atmosphere, visible in a deep twilight, they are made of ice crystals By Function: Ionosphere – 50km outwards, extends throughout the thermosphere and into the mesosphere below, absorbs cosmic rays, gamma rays, X-rays and shorter wavelengths of ultraviolet radiation, changes atoms to positively charged ions Ozonosphere/Ozone Layer – 19-50km, portion of stratosphere that contains an increased level of ozone, ozone is a highly reactive oxygen molecule made up of three oxygen atoms, absorbs shorter wavelengths of ultraviolet radiation CFC (Chlorofluorocarbons): refrigerant, propellant CFC + Ultraviolet  Chlorine Chlorine breaks down ozone UV Index – breakdown of exposure risk of UV rays Air – a simple mixture of gases that is naturally colorless, tasteless and formless, blended so thoroughly that it behaves as if it were a single gas, N2 (78%), O2 (21%) and others (1%), Water vapor varies from 0-4% and CO2 roughly (0.0035%) 4Less: odorless, colorless, tasteless and formless = Air Atmosphere thickness is about 480km (thermopause), beyond that altitude is the exosphere (outer sphere) Density = mass/volume, air density = 1.2kg/m-3, liquid water density = 1000kg/m-3 Air density decreases with increase of altitude

Elevation = height above point on earth, can stand on it Altitude = something above the surface, cannot stand on it Exosphere – “outer sphere”, where the rarefied, less dense atmosphere is nearly a vacuum, contains scarce lightweight, hydrogen and helium atoms, weakly bound by gravity as far as 32,000km from the earth By Composition: Heterosphere – 80~480km, distinct layers due to gravity, H2, He2 at the top of heterosphere, N2, O2 in the lower heterosphere Homosphere – below heterosphere, uniformly missed except for Ozone (O3), ozone in the “ozone layer” (19~50km) Compositionally, what are the layers on the atmosphere? Atmospheric Temperature Profile  Troposphere, Stratosphere, Mesosphere, Thermosphere Troposphere  Temp goes down with height, tropopause Stratosphere  Temp goes up with height (limited arc, cold air rises), stratopause Mesosphere  Temp goes down with height, mesopause Thermosphere  Temp goes up with altitude, low density, auroras, thermopause

Chapter 4: Transmission – refers to the passage of shortwave and long wave energy through the atmosphere or water Absorption – the assimilation of radiation by molecules of matter and its conversion from one form of energy to another Kinetic energy – energy of motion Potential energy – energy that is stored that has the capacity to do work under the right conditions Heat always flows from an area of high temperature into an area of lower temperature Sensible heat – heat that can be sensed by humans as temperature because it comes from kinetic energy of molecular motion Latent heat – “hidden heat”, energy gained or lost when a substance changes from one state to another like water vapor to liquid water = a change in phase Radiation – the transfer of heat in electromagnetic waves such as that from the Sun to Earth, the temperature of the object or substance determines the wavelength of radiation it emits, transfer of energy through outer space Conduction – the molecule-to-molecule transfer of heat energy as it diffuses through a substance, from higher to lower temperature Convection – the transfer of heat by mixing or circulating, transfer by vertical movement Advection – the transfer of heat by the flow of a fluid, horizontally dominant movement Insolation – the single energy input driving the Earth-atmosphere system yet it is not equal at all surfaces across the globe Scattering - atmospheric gases, dust, cloud droplets, water vapor and pollutants physically interact with insolation to redirect radiation, changing the direction of the lights movement without altering its wavelengths, accounts for the percentage of the insolation that does not reach Earth’s surface and is reflected back instead Diffuse radiation – incoming energy that reaches the Earth’s surface after scattering occurs Mie scattering – the process of larger particles scattering all wavelengths of visible light evenly, making the sky appear almost white

Reflection – a portion of arriving radiation that bounces directly back into space without being absorbed or performing any work Albedo – the ratio of reflected solar radiation to the incident solar radiation, high albedo surfaces are shiny,  Smooth surface reflects more than rough  Light color surfaces reflect more than dark Rayleigh Scattering Rule – the shorter the wavelength, the greater the scattering; the longer the wavelength, the less the scattering The sky is blue because blue light is scattering in our atmosphere because it is shortwave, red sunrise because red is longer wavelength than blue so as the sun rays come through the larger part of the atmosphere we see red Refraction – change in speed and direction of light as light passes from one medium to another, creates rainbows through water vapor acting as a prism dividing light Winds rapidly spread aerosols worldwide resulting in an increase in global atmospheric albedo and a temporary average cooling of 0.50C Global dimming – general term describing the pollution related decline in insolation to Earth’s surface Sun emits energy in longer wavelengths from its surface and atmosphere toward space Greenhouse Effect and Atmospheric Warming:  Atmosphere absorbs heat energy  A real greenhouse traps heat inside  Atmosphere delays transfer of heat from Earth into space Enhanced greenhouse gas emissions in a problem because they are further delaying the transfer of heat from earth to space, which further warms the planet, which really began to take off during the industrial revolution Cloud-albedo forcing – an increase in albedo caused by low, thick stratus clouds that reflect 90% of insolation Cloud-greenhouse forcing – trapping long wave radiation from Earth and raising minimum temperatures causing warming of Earth’s climate Net radiation (NET R) – the sum of all radiation gains and losses at any defined location on Earth’s surface, outgoing short wave = albedo x insolation, incoming shortwave = (1-albedo) x insolation, net radiation = incoming short wave – outgoing long wave

Open system – input  storage  output Energy Conservation Law – input – Output = storage change Steady State Equilibrium – input = insolation, output = reflected short wave + outgoing long wave, if ...