3ObjectivesObjective 1: Students know the Sun is the major source of Earth’s energy, and provides the energy driving Earth’s weather and climate.Explain how solar energy powers the water cycle.Explain how uneven heating of Earth’s surface determines weather and climate patterns.Objective 2: Students know the composition of Earth’s atmosphere has changed in the past and is changing today.Explain how variations in the ozone layer affect the amount of ultraviolet radiation entering the Earth’s atmosphere.Describe how life forms have affected the composition of the atmosphere over time.Describe how natural events have affected the composition of the atmosphere over time (e.g., volcanoes and meteorites).
4ObjectivesObjective 3: Students understand the role of the atmosphere in Earth’s greenhouse effect.Explain how the proportions of gases in the atmosphere affect weather and climate.Identify sources of greenhouse gases.Explain why a certain level of greenhouse effect is essential for life on Earth.Objective 4: Students know convection and radiation play important roles in moving heat energy in the Earth system.Explain how the processes of radiation, conduction, and convection occur in the atmosphere.Explain how the processes of radiation, conduction, and convection affect weather and climate.Objective 5: Students know Earth’s rotation affects winds and ocean currents.Identify that wind and ocean currents form global patterns based on Earth’s rotation.
5Key InfoEarth's atmosphere is a very thin layer wrapped around a very large planet.Two gases make up the bulk of the earth's atmosphere: nitrogen (78%), and oxygen (21%). Various trace gases make up the remainder.Based on temperature, the atmosphere is divided into four layers: the troposphere, stratosphere, mesosphere, and thermosphere.Energy is transferred between the earth's surface and the atmosphere via conduction, convection, and radiation.Ocean currents play a significant role in transferring this heat poleward. Major currents, such as the northward flowing Gulf Stream, transport tremendous amounts of heat poleward and contribute to the development of many types of weather phenomena.
6Interaction-Sun and Earth More than 99% of the Earth’s energy comes from the Sun in the from of visible light.The Earth also sends energy back into outer space, mostly as infrared radiation.On average, this transfer of this incoming and outgoing energy is nearly equal.Where does the Sun’s energy go on Earth?30% is reflected back to space.19% of the incoming solar energy is absorbed by the Earth’s atmosphere and clouds.The remaining 51% is absorbed by the Earth’s surface.Most of the energy that reaches the Earth’s surface is in the form of visible light.
7Energy – From Earth to Where? To maintain equilibrium, the Earth returns the energy it receives from the Sun back to space as infrared light.Only 6% of the energy goes directly from the Earth’s surface to space.About 15% of the Earth’s surface energy is absorbed by water vapor, carbon dioxide and other gases in the atmosphere. (greenhouse effect)The remainder of Earth’s surface energy is transferred to the atmosphere in a more complex exchange involving sensible and latent heat.Sensible heat is the energy associated with the temperature of a body. A warm surface will be at a higher temperature. Sensible heat flows from the surface to the atmosphere via convection (air circulations) or conduction (molecular motion).Latent heat is the energy associated with phase changes. In the atmosphere, water vapor condenses forming clouds and precipitation. This releases latent heat to the atmosphere. Latent heat also flows from the atmosphere to the surface during evaporation. Evaporation cools the atmosphere.So, infrared radiative transfer combined with flux of sensible and latent heat provides the energy to the atmosphere. This energy, which ultimately originated from the Sun, drives all of Earth’s weather and climate.
8What Does The Sun Energy Do On Earth? Powers the water cycle. (and many of the other biochemical cycles).Warms the atmosphere and surfaceDrives weather and climate through the uneven heating of the Earth’s surface.Provides needed energy for photosynthesis in plants
10The Water CycleWater: essential for life on earth. It is recycled through the water or hydrologic cycle.Amount of water on earth remains nearly constant and is continually recycled through time.Water molecules may remain in one form for a very long period of time and in other forms for very short times.Remember, this is all driven by energy from the sun!
11Water Cycle ProcessesEvaporation: changing of water from a liquid to a gas Condensation: changing of water from a gas to a liquid Sublimation: changing of water from a solid to a gas Precipitation: water molecules condense to form drops heavy enough to fall to the earth's surface
12Water Cycle ProcessesTranspiration: moisture is carried through plants from roots to leaves, where it changes to vapor and is released to the atmosphere Surface runoff, the flowing of water over the land from higher to lower ground Infiltration: the process of water filling the porous spaces of soil Percolation: groundwater moving in the saturated zone below the earth's surface
14Atmosphere – Its RoleAtmosphere Role: protects the Earth’s surface from the sun’s radiation and helps regulate the temperature of the Earth’s surface.What is the atmosphere?A mixture of gases the surrounds a planet.All weather on Earth occurs in the atmosphere and it is essential to life.
15Atmosphere Composition Composition of the atmosphere:Nitrogen 78%Oxygen 21%Carbon dioxide 0.03%Other gases 0.17%Water vapor (variable) 1-3%
16Layers of the Atmosphere (The Most Important Ones) Troposphere: closest to the Earth’s surface and where weather occurs. You can find the majority of the water vapor and carbon dioxide here (hey, it’s the greenhouse glass!)Stratosphere: from the top of the troposphere (known as the tropopause) to altitude of 50km. Ozone lives here (well almost all of it).Mesosphere: from the stratopause (the top of the stratosphere) to altitude of 80km. Coldest temperatures in the atmosphere!Thermosphere: Almost to the top. The only thing beyond is the ionosphere (aurora borealis zone) and exosphere (transition to space). Nitrogen and oxygen absorb solar radiation here.
17Greenhouse Gases and the Greenhouse Effect Greenhouse gases: carbon dioxide, methane, water vaporImportance of greenhouse gases: these gases help keep some of the radiation from going back to space. They help regulate the temperature of Earth and keep it habitable for life.Note: Interference from humans can cause increases of greenhouse gases in the atmosphere. When this happens, the Earth may get too hot!
18Sources of Greenhouse Gases Naturally through the biochemical cycles (Water cycle, carbon cycle, nitrogen cycle, etc), volcanes, etc.Human interference through CFC emissions and industrial activities.
19Atmosphere & OceanOceans cover nearly three-quarters of the earth's surface and play an important role in exchanging and transporting heat and moisture in the atmosphere.Most of the water vapor in the atmosphere comes from the oceans.Most of the precipitation falling over land finds its way back to oceans.About two-thirds returns to the atmosphere via the water cycle.You may have figured out by now that the oceans and atmosphere interact extensively. Oceans not only act as an abundant moisture source for the atmosphere but also as a heat source and sink (storage).
20Atmosphere-OceanOcean currents play a significant role in transferring this heat poleward. Major currents, such as the northward flowing Gulf Stream, transport tremendous amounts of heat poleward and contribute to the development of many types of weather phenomena. They also warm the climate of nearby locations. Conversely, cold southward flowing currents, such as the California current, cool the climate of nearby locations.
21Energy Heat TransferEnergy is transferred between the earth's surface and the atmosphere via conduction, convection, and radiation.Conduction: process by which heat energy is transmitted through contact with neighboring molecules.Convection transmits heat by transporting groups of molecules from place to place within a substance. Occurs in fluids such as water and air, which move freely.Radiation: the transfer of heat energy without the involvement of a physical substance in the transmission. Radiation can transmit heat through a vacuum.
23Conduction Air and water are relatively poor conductors. Most energy transfer by conduction occurs right at the earth's surface.At night, the ground cools and the cold ground conducts heat away from the adjacent air.During the day, solar radiation heats the ground, which heats the air next to it by conduction.
24ConvectionIn the atmosphere, convection includes large- and small-scale rising and sinking of air masses and smaller air parcels.These vertical motions effectively distribute heat and moisture throughout the atmospheric column and contribute to cloud and storm development (where rising motion occurs) and dissipation (where sinking motion occurs).
25Convection CellsConvection cells distribute heat over the whole earth.Consider a simplified, smooth earth with no land/sea interactions and a slow rotation. Under these conditions, the equator is warmed by the sun more than the poles. The warm, light air at the equator rises and spreads northward and southward, and the cool dense air at the poles sinks and spreads toward the equator. As a result, two convection cells are formed.Meanwhile, the slow rotation of the earth toward the east causes the air to be deflected toward the right in the northern hemisphere and toward the left in the southern hemisphere. This deflection of the wind by the earth's rotation is known as the Coriolis effect.
27RadiationEnergy travels from the sun to the earth by means of electromagnetic waves.The shorter the wavelength, the higher the energy associated with it.Most of the sun's radiant energy is concentrated in the visible and near-visible portions of the spectrum. Shorter-than-visible wavelengths account for a small percentage of the total but are extremely important because they have much higher energy. These are known as ultraviolet wavelengths.
29ObjectivesObjective 1: Students know how successive rock strata and fossils can be used to confirm the age, history, and changing life forms of the Earth, including how this evidence is affected by the folding, breaking, and uplifting of layers.Explain the basics of the process of fossil formation.Apply the principles of superposition to relative dating of rock layers.Describe the process of absolute dating.Sequence the age, history, and changing life forms of Earth using strata and fossil evidence.Describe how folding, breaking, and uplifting of strata complicate geological evidence.Objective 2: Students understand the concept of plate tectonics including the evidence that supports it (structural, geophysical and paleontological evidence).Describe how convection in Earth’s mantle has changed the locations + shapes of continents based on tectonic plate movement.Identify the evidence for seafloor spreading.Identify the three major types of tectonic plate boundaries.
30ObjectivesObjective 3: Students know elements exist in fixed amounts and move through solid earth, oceans, atmosphere and living things as part of biogeochemical cycles.Explain how matter and energy are transferred chemically through systems that include living and non‐living components.Objective 4: Students know processes of obtaining, using, and recycling of renewable and non‐renewable resources.Identify the differences between renewable and non‐renewable resources.Explain how recycling reduces the rate of depletion of nonrenewable resources.Identify the processes used to obtain natural resources (e.g., mining, oil production, water, and agriculture).Objective 5: Students know soil, derived from weathered rocks and decomposed organic material, is found in layers.Describe the structure of soil, its components, and its formation
31FossilsDifferent rock layers contain different fossils (key to dating the geologic past)Fossils: the remains of animals or plants that lived in a previous geologic timePaleontology: the study of fossilsFossils provide information to the relative and absolute ages of rocks, as well as provide clues to past geologic events, climates, and evolutiom
32FossilizationGenerally, only the hard parts of organisms become fossils. Fossilization processes are:MummificationAmber: hardened tree sapTar SeepsFreezing: almost completely preservedPetrification: replica of the original organism
33Fossil TypesTrace fossil: a fossilized mark that formed in sedimentary rock by the movement of an animal on or within soft sedimentIndex fossil: fossils that occur only in rock layers of a particular geologic age (used to determine the relative age of rock layers)Must be present in rocks scattered over a large regionMust have features that clearly distinguish it from other fossilsOrganism must have lived during a short span of geologic timeMust occur in fairly large numbers within the rock layers
34Rock CycleRocks: naturally occurring aggregates of one or more minerals.Composed of material that has been present on Earth since it first formed – excluding that material which has been delivered by meteoritesRock Cycle: a model that illustrates the changes to rocks that have taken place through time.Rocks are recycled into other rocks through processes which occur in mainly two locations; at or near Earth’s surface such as weathering, erosion, and deposition; and deep below the surface such as melting and increased heat and pressure. Most rocks are formed from other rocks and a “rock” may take more than one path through the rock cycle.
36Rock Cycle and Rock Types Metamorphic rock: metamorphic rock would need to experience an increase in temperature to the point of melting it, creating magma.Eventually this magma body would enter an environment where the heat contained would transfer from it (cooling) and the process of solidification (crystallization) occurs. This rock is now classified as an igneous rock.Igneous rock: several more changes must occur in order to turn this igneous rock into a sedimentary rock.The igneous rock needs to be subjected to the agents of weathering and erosion, which over geologic time creates pieces or fragments of rock called sediment. As this sediment piles up, compaction and cementation turn the loose sediment into a solid rock through the process of lithification. This rock is now classified as a sedimentary rock.Continuing clockwise this sedimentary rock will become a metamorphic rock with the addition of heat and pressure causing a partial melting of some of the minerals in the sediment. This process is referred to as metamorphism and results in creation of a metamorphic rock. The straight arrows within the rock cycle diagram indicate that any one rock type can turn into any other rock type by passing through several common processes.
37Rocks and Minerals Key Points: Fossils Superposition Absolute dating Rock TypesMineral Information
38External Forces Processes that wear the Earth’s surface down 1. Weathering: the breaking down of rocks into smaller pieces (assists in the formation of soil)Physical weatheringChemical weathering2. Erosion: the process by which rock material at Earth’s surface is removed and carried awayGravity and waterGlacierWind
39Physical WeatheringRock is broken into smaller fragments by physical agentsExample: water seeps into cracks, in a rocks and freezes, the water expands, breaking the rock apartExample: roots of plants growing in cracks can also force rocks apart
41Chemical WeatheringThe breaking down of rocks through changes in their chemical make-upChanges take place when rocks are exposed to air or waterExample: rainwater + carbon dioxide = weak acid that dissolves certain minerals in rocks causing rocks to fall apartExample: oxygen + water + iron in rocks = iron into rust, crumbles easily
42ErosionGravity and water: gravity moves water downhill, running/flowing water erodes rock materialExample: Grand CanyonGlaciers: masses of ice that from in places where more snow falls in winter than melts in summerGlacier moves downhill slowly, grinding and removing rock materialWind: dry desert areas, sand grains blown along by the wind scrape and scour rock outcrops, slowly carving them into unusual shapes
43Check for Understanding Erosion is the process by which rocks at the Earth’s surfaceA. Are removed and carried awayB. Crumble and decayC. Turn into rustD Melt to form magma
44Internal Forces Processes that shape the Earth’s surface. Produces: Mountains: produced by faulting and foldingEarthquakes: produced by strong vibrations along faultsVolcanoes: a hole in Earth’s crust through which lava flows from underground; lava cools to form solid rockPlains: broad flat regions found at low regions; often made of layered sedimentary rocks that were formed underwater and slowly raised above sea levelPlateaus: large areas of horizontally layered rocks with higher elevations than plains; formed by either a large block of crust rising up along faults, or being gradually uplifted without faulting, or built up by lava flows
45FoldingForces in Earth’s crust press rocks together from the sides, bending the layers into folds. The land is squeezed into upfolds and downfolds, forming ridges and valleys.
46FaultingOccurs when forces in the crust squeeze or pull rock beyond its capacity to bend or stretch. The rock then breaks and slides along a crack or fracture, called a fault, relieving the stress in the crust
47Plate TectonicsTheory that explains how internal forces that shape the Earth’s crust move and work.Movements cause mountain building, volcanic activity, and earthquakes along the plate edgesEarth’s crust is divided into multiple plates that slowly move.Divergent plates: plates that are moving away from each otherTransform plates: plates that are sliding past each otherConvergent plates: plates that collide
49How Plate Tectonics Work Plate motions caused by heat circulating in Earth’s mantle (the thick zone of rock beneath the crust)
50How Plate Tectonics Work Continental plate collision produces mountain ranges (ex. Himalayas)Plates sliding past each other produce fault zones and earthquakes (ex. San Andreas Fault)Plates spreading apart produce ocean basinsContinental drift: large continents are broken into smaller landmasses that move away from each other.(Have you ever heard of Pangaea?)
51Ocean Floor FeaturesMid-ocean ridge: a long underwater mountain chain where rising magma forms new ocean crust; new crust is added to crustal plates that spread away from the ridge (seafloor spreading)Trenches: underwater valleys that from the deepest part of the ocean floor; found where where a plate of ocean crust collides with another plate and is forced to slide under it, back into Earth’s mantle (causes volcanic activity and mountain building along the edge of the upper plate)Continental shelves: areas of the seafloor that slope gently away from the coastlines of most continentsContinental slopes: drop away from the outer edges of continental shelves to the great depths of the ocean; level off into the deep ocean floor
52Cool Fact Along the ocean floor, there are ridges and valleys Seamounts are tall underwater mountains. Most were formed by volcanoesWhen the top of a seamount rises above the water’s surface, an island is forms.The Hawaiian Islands are the tops of a chain of volcanic seamounts.
53Check for Understanding The theory that Earth’s crust is broken up into large pieces that move and interact is called(a) evolution(b) mountain building(c) the rock cycle(d) plate tectonics
54Rock DatingRelative Age: the age of an object in relation to the ages of other objectsLaw of superposition: an un-deformed sedimentary rock layer is older than the layers above it and younger than the rock layers below itAbsolute Dating: numeric age
55Absolute Dating Rates of erosion or depositions Varve count: definite annual sedimentary depositsRadiometric dating: method of using radioactive decay to measure absolute ageHalf-life: the time it takes half the mass of a given amount of a radioactive isotope to decay into its daughter isotopeCarbon datingFossil record