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Earth System Science (ESS) • The study of the interactions between and among events and Earth’s spheres • A relatively new science (1988) 1.1 What Is Earth Science? Encompasses all sciences that seek to understand • Earth • Earth's neighbors in space Earth science includes 1. geology, the study of Earth a. Physical geology examines the materials composing Earth b. Historical geology is the study of the origin and development of Earth •topics including minerals and rocks, volcanoes, earthquakes, faults and folds, soils, erosion, mountains, plate tectonics, and geologic history. 1.1 What Is Earth Science? Earth science includes 2. oceanography, the study of the ocean a. Oceanography integrates 1. Chemistry 2. Physics 3. Geology 4. Biology We will explore our four major oceans, the properties of seawater, ocean floor and coastline features, ocean sediments, and major ocean currents. 1.1 What Is Earth Science? Earth science includes 3. meteorology, the study of the atmosphere and the processes that produce weather This Includes the study of: clouds and precipitation types, storms such as hurricanes and tornadoes, and fronts, pressure systems, and weather maps. 1.1 What Is Earth Science? Earth science includes 4. astronomy, the study of the universe Includes such topics as the sun and other stars, planets and other objects in our solar system, lunar phases, tides, and eclipses. Fields of Earth Science • • • • • • • • • Astronomer Cartographer Geologist Petroleum Geologists Oceanographer Meteorologist Volcanologist Seismologist Hydrologists Formation of Earth Most researchers believe that Earth and the other planets formed at essentially the same time from the same primordial material as the Sun.. Nebular Hypothesis • The solar system evolved from an enormous rotating cloud called the solar nebula. Formation of Earth Nebular Hypothesis • The nebula was composed mostly of hydrogen and helium. • About 5 billion years ago, the nebula began to contract. • It assumed a flat, disk shape with the protosun (pre-Sun) at the center. Nebular Hypothesis • Inner planets begin to form from metallic and rocky clumps. • Larger outer planets began forming from fragments with a high percentage of ices. A B C D E Layers Form on Earth • As Earth formed, the decay of radioactive elements and heat from high-velocity impacts caused the temperature to increase. • Iron and nickel began to melt and sink toward the center • Lighter rocky components floated outward, toward the surface. • Gaseous material escaped from Earth’s interior to produce the primitive atmosphere. Earth’s Sphere • Atmosphere • Hydrosphere • Lithosphere /Geophere • Biosphere • Cryosphere • Anthrosphere 1.2 A View of Earth 1. Hydrosphere • Ocean is the most prominent feature of the hydrosphere. - Is nearly 71% of Earth's surface - Holds about 97% of Earth's water • Also includes fresh water found in streams, lakes, and glaciers, as well as that found underground • A gaseous sphere and it envelopes the Earth, • Thin, tenuous blanket of air • One half lies below 5.6 kilometers (3.5 miles) • Consists of a mixture of gases composed primarily of nitrogen, oxygen, carbon dioxide, and water vapor. Atmosphere http://player.discoveryeducation.com/index.cfm?guidAssetId=0 E074343-4F75-4D95-815B4329F2FD016F&blnFromSearch=1&productcode=US Biosphere • All life on earth, including man, and all organisms. • The life zone on our planet distinguishes our planet from the others in the solar system. 1.2 A View of Earth 4. Geosphere: Lithosphere & Asthenosphere • Based on compositional differences, it consists of the crust, mantle, and core. - Crust—the thin, rocky outer layer of Earth. - Mantle—the 2890-kilometer-thick layer of Earth located below the crust. - Core—the innermost layer of Earth, located beneath the mantle. 2. Divisions of outer portion based on how materials behave • a. Lithosphere - rigid outer layer – 1. Crust – 2. Uppermost mantle • b. Divisions of Earth’s surface – 1. Continents (Continental Crust) – 2. Ocean Basins (Oceanic Crust) • C. The asthenosphere is a semi-fluid layer of partly molten rock located below the Lithosphere Earth’s Layered Structure Lithosphere • The Earth's solid surface, often called the crust of the earth. It includes continental and oceanic crust as well as the various layers of the Earth's interior. 8/1/2012 Unit 1 Cryosphere • The portion of the Earth's surface where water is in a solid form • Snow or ice: includes glaciers, ice shelves, snow, icebergs, and arctic climatology Anthrosphere • Man and his direct ancestors, hominids. • The human population, it’s buildings, dams, and other constructions. IV. Earth system science Interconnected Spheres • Spheres are closely connected • Changes are often chain reactions • A change in one sphere results in changes in others - called an event – Forest fire destroys plants in an area • Interactions between spheres – No plants => erosion – Soil in water => increased turbidity – Turbidity => impacts water plants/animals Event <=> Sphere • Causes & Effects • Interactions • Event <=>Sphere • Sphere<=>Sphere ESS Analysis • Events – Cause-effect events – Interactions – Natural events • Earthquake, hurricane, forest fires – Human caused events • Oil spill, air pollution, construction Understanding Interactions • Global implications • Helps people predict outcomes • Preparation for natural disasters • Environmental impacts of human activities 1.4 Earth System Science Earth is a dynamic body with many separate but highly interacting parts or spheres. Earth system science studies Earth as a system that is composed of numerous parts, or subsystems. 1.4 Earth System Science A system is any size group of interacting parts that form a complex whole. Closed systems are self contained (e.g., an automobile cooling system). Open systems allow both energy and matter to flow in and out of the system (e.g., a river system). Earth Systems • Although we study four branches of earth science, there are many interactions between earth’s systems. You are standing on the ___sphere. You are breathing in part of the ______sphere. If you went to the beach or canoed down the Chattahoochee River you where visiting the ______sphere. And you and all the other living things on earth make up the _____sphere. 1.4 Earth System Science Consists of a nearly endless array of subsystems or cycles Cycles Include: Hydrologic Cycle, Rock Cycle, Geochemical Cycles (carbon, nitrogen, and phosphorous) Humans are part of the Earth system. All Matter above and beneath the Earth’s surface moves in cycles. What drives the earth cycles? Sun radiates heat down on Earth’s hot core or the ocean of air and geothermal energy water spreads upward 1.4 Earth System Science Sources of Energy • Sun—drives external processes such as weather ocean circulation erosional processes • Earth’s interior—drives internal processes volcanoes, earthquakes mountain building Magic School Bus Water Cycle http://www.youtube.com/watch?v=AQKdkponoZM&feature=relate d Water cycle constantly transfers the world’s water between three basic storage reservoirs. • Oceans contain 97% of Earth’s water • Of the 3% of the Earth’s freshwater: – 2.15% is locked away in glaciers and ice sheets – 0.62% is groundwater, stored as soil moisture – 0.009% is in rivers and lakes – 0.001% is in the atmosphere Fresh water Amazingly, water in lakes & rivers, water in rain & snow, water in our bathtub, shower, and drink bottles, amounts to only about 1% of the water in the world. The Water (Hydrologic) Cycle • Ocean to Atmosphere – 84% vapor from oceans; 16% from continents • Atmosphere to Surface – Vapor cools, condenses & precipitates out in a week, or few hours or few centuries; depends. – 77% precipitation falls on the oceans • Surface to Ocean – 23% of precipitation in water cycle meets our needs via “surface water” and “ground water.” Major steps in the water cycle: • Ocean to Atmosphere • Atmosphere to Surface • Surface to Ocean Water Cycle Animation by NASA http://www.youtube.com/watch?v=Az2xdNu0ZRk How do the different types of precipitation form? • Rain--Vapor condenses around aerosols and falls from sky. How do the different types of precipitation form? • Snow—ice crystals that assemble themselves as they fall through a cloud How do the different types of precipitation form? • Hail--large frozen rain formed in a giant cloud of an intense thunderstorm. How do the different types of precipitation form? • Sleet--falling snow may partially melt and then refreeze into a frozen raindrop. S U N WATER CYCLE Precipitation Precip and Conden Movement of water vapor by wind Evaporation & Transpiration Mountains Run Off LAKES Streams Evaporation OCEANS Aquifer Groundwater Humans affect the water cycle • Higher global temperature increased evaporation. • Higher ocean temps increase evaporation • Reduction in rainforest reduces transpiration. • Reduction of plant life increases runoff • Glacial melting reduces amount of reflected light Geochemical Cycles Carbon Cycle • Early atmosphere of Earth 95% CO2. Photosynthetic plants removed some of the CO2 and added O2. Today’s atmosphere is 0.04% CO2! • Reactions of photosynthesis and cellular respiration Carbon is found in the couldn’t take place without carbon. These two reactions form a atmosphere continuous primarily cycle. as CO2 • Two important sources of Carbon are the ocean (since CO2 dissolves easily in H20) and rocks (such as coal, ore and limestone formed fromRespiration dead organisms) Photosynthesis : Cellular : Plants taking CO2 out of the atmosphere and using it to produce sugar. Organisms take that sugar and in the process of burning energy release CO2 back into the atmosphere. And, another way to look at the carbon cycle: Humans affect the Carbon Cycle • Burning of fossil fuels, (oil, coal and natural gas). • Fossil fuels were formed very long ago and is “fixed”: essentially locked out of the carbon cycle. • By burning fossil fuels the carbon is released back into the cycle. Humans affect the Carbon Cycle • We presently release more carbon into the air than can be reabsorbed by photosynthetic organisms, thereby we have a net INCREASE of carbon in the cycle. • This atmospheric carbon has a role to play in the warming of the atmosphere. Geochemical Cycles • • • • Nitrogen Cycle Organisms require Nitrogen to form amino acids for the building of proteins. Lots of N2 in our atmosphere Unfortunately, most organisms CANNOT use atmospheric nitrogen. Nitrogen-fixing Nitrogen-fixing bacteria CAN usebacteria N2 fromconvert the atmospheric N2 into ammonia atmosphere. (NH4) which is a form of nitrogen that plants CAN use. Nitrogen Cycle Summary • Nitrogen makes up 78% of atmosphere as N2 • Nitrogen-fixing bacteria are very important - N2 needs to be “fixed” before it can be used by most living things. NITROGEN CYCLE N2 Fertilizer Production Lightning Denitrification (GAS ) Crops Sheep LegumeFixation Nitrogen-Fixing Bacteria in soil & roots Decomposers Ammonia Nitrates Nitrites Nitroge n Humans affect the Nitrogen Cycle • From the production and use of nitrogen fertilizers to the burning of fossil fuels in automobiles, power plants, and industries, humans impact this cycle. • Excessive nitrogen additions can pollute ecosystems Humans affect the Nitrogen Cycle • Increased global concentrations of nitrous oxide (N2O), a potent greenhouse gas, in the atmosphere • Increased concentrations of nitric oxide, (NO) that drive the formation of smog along with N2O • Losses of soil nutrients such as calcium and potassium that are essential for long-term soil fertility Humans affect the Nitrogen Cycle • Acidification of soils and of the waters of streams and lakes • Greatly increased transport of nitrogen by rivers into estuaries and coastal waters where it is a major pollutant. How do “rocks” “cycle” ? http://www.youtube.com/watch?v=Jslupi0iW7g Igneous, Sedimentary, Metamorphic Each type of rock records a different complex past. Each type of rock can be changed from one form to another and back again. geologists call these transformations the “rock cycle” Rocks • Igneous = formed by the cooling and crystallization of magma (melted rock) • Sedimentary = formed from accumulation of weathered material (sediments) • Metamorphic = formed from preexisting rocks that have been transformed (changed) Rock Cycle http://www.youtube.com/watch?v =ehcshoYIIM4&feature=related