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Welcome to Geosc 40, January 16 th (Lectures 1 & 2) Intro & The Nature of Scientific Inquiry and Origin of Water on Earth Today’s Music: Led Zeppelin “The Ocean” Star One “Songs of the Ocean”“Songs of the Ocean” Instructor: Prof. Chris Marone TA’s: Laura Herren, Kerry Ryan, Joe Orlando Lecture: TR 1:00pm-2:15pm Instructor: Prof. Chris Marone TA’s: Laura Herren, Kerry Ryan, Joe Orlando Lecture: TR 1:00pm-2:15pm
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A 3-Credit Course Expectations? Lecture: 3 hours per week Reading: 2-4 hours per week
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Geosciences 40: The Sea Around Us A 3-Credit Course Lecture: 3 hours per week Reading: 2-4 hours per week Book: Recommended Trujillo & Thurman“Essentials of Oceanography" (11 th Ed. or similar) Read Details on the course web page and the Preface and Chapter 1 Keep Up with Your Reading!
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Geosciences 40: The Sea Around Us Visit the Web Page: www.geosc.psu.edu/geosc040 A Multimedia,General Education, Oceanography Course Course information --schedules, policies, news and info. Lecture note outlines Graphic resources Links to interesting oceanography-related sites
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Geosciences 40: The Sea Around Us Visit the Web Page: www.geosc.psu.edu/geosc040
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Geosc. 40: The Sea Around Us Course Requirements and Grading Policy 15%--In Class Exercises (using iClickers) 15%--Homework (Angel) 15%--On-line Assignments (Angel) 20%--Two Quizzes (e-testing center) 20%--Midterm Exam; In Class 15%--Final Exam (optional); 5% Extra Credit is Possible (see Web Page for details) Lecture Quizzes and Examinations cover material in lecture and reading; you are responsible for all material discussed or assigned. Exams are multiple choice & true/false and may use figures and plots from lecture.
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Why Attend Class? 15% of your grade is based on in Class Exercises (using clickers)
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iClicker. Required for the course Follow instructions to register on Angel We will use these in every class
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How many people visited the beach in 2013? A.I did B.I didn’t Pepsi
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Student Distribution By Year: I am in my: A)1st year B)2nd year C)3rd year D)4th year E)5+ yipee!
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Which is/are true? A)I have looked at the course web site B)I have finished on-line assignment 1 C)A & B D)None of the above
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What is “Oceanography” ? Study of the origin of water, physical and chemical properties of seawater, ocean circulation (both surface and deep), air/sea interactions, the organisms that inhabit the seas and their ecology and evolution, beaches, formation and morphology of the ocean basins. Fields: Interdisciplinary Physics, Chemistry, Biology, Geology
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Organization of Course I. Water & Heat--the Key Ingredients --origin, composition, circulation II. Life Goes On --lifestyles of plankton, fish, coral reefs III. The Changing Coastline --waves, tides, beach processes IV. The Dynamic Ocean Basins --making the ocean basins and associated hazards
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The Oceans Are Important Headlines Everyday Global Average Temperature Record High again in 2012! Coral Bleaching Devastates Reefs, Caribbean/Indian Oceans Record Atlantic Hurricane Season in recent years Indian Ocean Tsunami responsible for at least 150,000 deaths in coastal regions, Dec., 2004 PA farmers to sue EPA over restrictions to limit nutrient inputs to Chesapeake Bay (2011) New Limits Imposed on Bottom Fish Catches Fish Farming: Can it Meet the World's Demand for Fish Without Ruining the Environment? 2010, First Census of Marine Life results presented. Eruption of Eyjafjallajokul volcano at midocean ridge disrupts air travel
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The Oceans: Headlines Everywhere Washington Post 8/30/03 Centre Daily Times 9/1/03 Ocean Currents Studied by Tracking Toy Ducks…
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Ocean Surface Currents
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Green Shipping, Blowing in the Wind… http://www.theage.com.au/
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Nah, you gave them a pass on Tuesday hey, maybe I should just end lecture here…
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The Origin of Water on Earth (The Oceans!) and The Nature of Scientific Inquiry Pepsi
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Water reservoirs Ah, but the oceans contain only a small portion of Earth’s total water -- most of Earth’s water is in its interior! The oceans contain nearly all of Earth's surface water (>97%) lakes & rivers = 0.01% of available water ice (glaciers and ice caps) & groundwater = 2.5% atmosphere (water vapor) = <0.001%
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The Origin of Water on Earth and in The Oceans Was it always here? What about in the earliest stages of Earth’s history Have we always had the same amount of water? Have the oceans always been the same size? Has ocean water always tasted the same?
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Oceans --How Much, How Big? Oceans cover 71% of Earth’s surface (3.6x10 8 km 2 ) That’s a lot of football fields….. 7.2x10 10 or 72 billion to be exact
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Oceans --How Much, How Big? Oceans cover 71% of Earth’s surface (3.6x10 8 km 2 ) Average ocean depth 3.8 km compare to 0.84 km avg. land height Highest point on land Mt. Everest-- 8.84 km (29,035’) Deepest point in the ocean Marianas Trench-- 11.02 km Water in oceans (how much?) 1.37 x 10 9 km 3
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Oceans --How Much, How Big? The world ocean contains 1.4 x 10 9 km 3 of (salty) water How many times would that fill this room? 100 Thomas: 0.06x0.06x0.01 = 3.6x10 -5 km 3 ~ 1.2 x 10 9 km 3 / 4 x 10 -5 km 3 = 3x10 13 30,000,000,000,000
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Two Major Hypotheses There’s a lot of water out there…. Where did it come from?
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Seawater Origin and Evolution Is it a planet ?! The chemical evolution of Earth’s ocean and atmosphere is intimately related to the processes that formed the Earth--the water planet. Why does Earth have liquid water whereas the other planets do not at present? Or do they? ET? Comet, meteorite impact
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Two Major Hypotheses There’s a lot of water out there…. Where did it come from? Earth Belch –degassing of volatile chemical species (water, C02, etc. Substances easily driven off by heat Volcanic Eruptions, Hot Springs, Seafloor Vents E.T ? Comets and meteorites. Impacts big and small
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So, Where Did the Oceans Come From, Anyway?
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How Science Gets Done And How Concepts Evolve Ah, but the oceans contain only a small portion of Earth’s total water -- most of Earth’s water is in its interior!
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The Scientific Method is Based on Empirical Observations, Skepticism and Repeated Measurements
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Empirical vs Belief-Based Approaches Truth is based on authority (of texts, self- proclaimed or selected leaders, legends, etc.) and is generally inviolable. Truth is based on application of a standardized method and repeated tests to confirm a result, and is subject to change as new methods are developed and new results discovered. In other words, theories evolve…
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Belief-based vs. empirical approaches to knowledge The Source Of Authority? Belief system Definitions are simply decrees. They are not based on Science
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The Theory of Evolution is Based on The Scientific Method A theory based on scientific principles and rigorously tested by skeptical scientists for over a century and a half!
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15% of your grade is based on in Class Exercises (using clickers) Marone’s Theory of Grades
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Empirical* system: Measurements Observations Hypotheses Theories Scientific Method Parameter “X” Parameter “Y” “Correlations” *empirical means “experiential” or “searching for interrelationships”
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Scientific method: definitions FACT : observation repeatedly confirmed HYPOTHESIS: testable statement about the natural world (a working model) THEORY: a set of verified hypotheses that explain how things work. A theory explains most or perhaps all of the observations, but ‘the jury is still out,’ for one reason or another. LAW: generalization of how some aspect of natural world behaves under stated circumstances; repeatedly-verified explanation of some aspect of the natural world
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1. Initial observation of materials/phenomena/behavior 2. Development of questions/establishment of constraints 3. Formulation of models to explain behavior: MULTIPLE WORKING HYPOTHESES 4. Testing of hypotheses through observation/experiment; COLLECTION OF DATA (MEASUREMENTS) 5. Analysis of data, evaluation/interpretation of results (ELIMINATE HYPOTHESES) 6. Formulate conclusions. THE SCIENTIFIC METHOD
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Scientific Method Hypotheses and Theories must be falsifiable. That is, we can never “prove” an hypothesis, we can only disprove it We must accept some uncertainty until substantial observations and tests have been conducted. Some problems do not yield easily and answers are complex (for example--the origin of water on Earth; the carbon cycle; global climate, earthquake preciction Hypotheses and Theories must be falsifiable. That is, we can never “prove” an hypothesis, we can only disprove it We must accept some uncertainty until substantial observations and tests have been conducted. Some problems do not yield easily and answers are complex (for example--the origin of water on Earth; the carbon cycle; global climate, earthquake preciction
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The Habitable Zone Where did Earth’s Water Come From? And Why is it Still Here?
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Seawater Origin and Evolution Earth: The Third Stone from the Sun (Jimi is not dead!) The chemical evolution of Earth’s ocean and atmosphere is intimately related to the processes that formed the Earth--the water planet. Why does Earth have liquid water whereas the other planets do not at present? Or do they? Where’s Pluto?
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Seawater Origin and Evolution Is it a planet ?! The chemical evolution of Earth’s ocean and atmosphere is intimately related to the processes that formed the Earth-- the water planet. Why does Earth have liquid water whereas the other planets do not at present? Or do they? The “Goldilocks Principle”
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Planetary mass High gravity retains light volatile gases = thick atmosphere Low gravity loses all atmospheric gases Boiling breaks chem bonds Freezing stops all biochem rxns 0° 100° LIFE ZONE s o l i d l i q u i d g a s SURFACE TEMPERATURE Distance from sun The “Goldilocks Principle” * (°C) ATMOSPHERIC COMPOSITION INTERNAL COMPOSITION http://www3.geosc.psu.edu/geosc040/40.lecture_files/
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NASA “Global Surveyor” mission map of ancient oceans on Mars (orbiter, 1997) WATER on MARS 4 BILLION YEARS AGO? Photos and mosaic JPL/ NASA The Grand Canyon of Mars - Valles Marineris 3000 km Water-formed gullies in crater
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Summary: Origin of Water on Earth and in the Oceans Two Major Hypotheses Earth Belch –degassing of volatile chemical species (water, C02, etc. Substances easily driven off by heat Volcanic Eruptions, Hot Springs, Seafloor Vents E.T ? Comets and meteorites. Impacts big and small
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But….. Remember, Theories Evolve… NASA’s LCROSS mission in 2010 discovered “significant water on the moon.” And, according to a paper just published in Nature Geoscience, Moon Water Differs from Earth Water Moon rocks show that lunar water has more heavy hydrogen than does terrestrial water, indicating a cometary origin. Could some of Earth’s water have originated from comet bombardment? “Houston, we have a problem”
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Ocean water most likely formed: a)During the first 0.5 x 10 9 years of Earth’s history b) Largely from emission (degassing) of materials (volatiles) from Earth’s interior c) From melting of glaciers and polar ice caps d) (a) and (c) e) (a) and (b) So, How Would You Answer This Question?
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Ike the Spike says “Read Chapter 5, it’s a hit!)
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