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How Do We Study Earth's Systems? © Jones & Bartlett Learning, LLC © Jones & BartlettCHAPTER Learning, LLC NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION 1 Introduction:© Jones & Bartlett Learning,How LLC Do We ©Study Jones & Bartlett Learning, LLC Earth’sNOT Systems? FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION Chapter© Jones Themes & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION Why study the history of Earth? How did the science of Earth systems arise? What is a system and how does it work? © Jones & WhatBartlett are Earth’s Learning, systems LLC and what are their basic ©characteristics? Jones & Bartlett Learning, LLC NOT FOR SALEHow do OR Earth’s DISTRIBUTION systems interact? NOT FOR SALE OR DISTRIBUTION Why is geologic time important to understanding how Earth’s systems interact? How do different processes act on different durations of time? How do we use the scientific method to study Earth’s systems and the history of their interactions? © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION Chapter Outline © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION 1.1 Why Study the History of Earth? 1.5 Geology as an Historical Science 1.2 What Are the Major Earth Systems and 1.6 The Scientific Method and the Study of What Are Their Characteristics? Earth’s Evolving Systems © Jones & BartlettGeologic Learning, Time and LLCProcess © JonesSummary & Bartlett Learning, LLC NOT FOR SALE 1.3 OR DISTRIBUTION NOT 1.7 FOR SALE OR DISTRIBUTION 1.4 Directionality and Evolution of Earth Systems © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION 3 © Jones & Bartlett Learning, LLC. NOT FOR SALE OR DISTRIBUTION. 7 © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION 6 5 Green Revolution © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC World War II 4 NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION Advances in medicine/sanitation Railroads and steamships 3 Industrial Revolution Emigration to New World begins ©Population (billions) Jones2 & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC Black Death—the plague NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION Rome Rise of Crusades begin Neolithic agricultural revolution falls Islam 1 0 © Jones & Bartlett8000 Learning,1 LLC 500 © Jones &1000 Bartlett Learning,1500 LLC 2005 B.C. A.D. NOT FOR SALE OR DISTRIBUTION NOTYear FOR SALE OR DISTRIBUTION FIGURE 1.1 Human population growth. Global human population growth since 8000 B.C. [Data from: U.S. Census Bureau, Inter- national Programs Center, 2001.] Why Study© Jones the History & Bartlett of Earth? Learning, LLCenvironments at rates much© Jones faster than& Bartlett the rates Learning, of LLC 1.1 NOT FOR SALE OR DISTRIBUTIONnatural processes. The rapidNOT growth FOR of humanSALE popula OR DISTRIBUTION- This book is about Earth, the natural processes tions (FIGURE 1.1) has led to the spread of agriculture that shape it, and the history of these processes and their and deforestation, heavy industry and power plants interactions through vast intervals of time. Geology is fired by fossil fuels, and the dependence on petroleum the science that studies the history of the Earth and its (oil and gas) to power automobiles for transportation life© Jonespreserved & as Bartlett fossils. Learning, LLC (FIGURE ©1.2 Jones). & Bartlett Learning, LLC NOT FORWhy SALEshould weOR be DISTRIBUTION concerned about Earth’s NOTThe burning FOR ofSALE fossil fuelsOR releasesDISTRIBUTION greenhouse history? Because understanding how Earth changes gases, especially carbon dioxide, into the atmosphere. tells us about how natural processes affect humans Greenhouse gas traps solar radiation as heat in Earth’s and how humans affect natural processes. Many natu- atmosphere, causing the atmosphere and Earth’s sur- ral processes act so slowly we would be unaware of © Jones & Bartlett Learning, LLC © Jonesface & to Bartlett warm (FIGURE Learning, 1.3). Without LLC carbon dioxide in them except for the geologic record of their activities the atmosphere, Earth’s surface temperature would be NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION preserved in the rocks. Most people are unaware that about -18°C (Celsius), or about -0.5°F (Fahrenheit), Earth’s environments are constantly changing. We instead of its current (and more comfortable!) tem- assume landscapes—mountains, valleys, rivers and perature of +15°C (59°F). But humans have begun to streams, coasts, and oceans—do not change because burn fossil fuels at an unprecedented rate, and no one the changes are typically© Jones so slow & Bartlett and subtle Learning, they take LLCreally knows what the outcome© Jones will & be Bartlett of the rapid Learning, LLC place over time spansNOT equivalent FOR SALE to many, OR manyDISTRIBUTION hu- accumulation of carbon NOTdioxide FOR in the SALE atmosphere. OR DISTRIBUTION man generations: from many millions of years down to In fact, carbon dioxide levels in the atmosphere have millennia and centuries. Also, some processes are so increased about 30% since the beginning of the Indus- infrequent or sudden we would not know they occur trial Revolution (FIGURE 1.4). We know this based on except, again, to look at the geologic record. carbon concentrations in gas bubbles found in cores © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC Scientists have only recently begun to appreci- taken through the glacial ice of Greenland and Ant- ateNOT just FOR how strongly SALE changesOR DISTRIBUTION in Earth’s environments arctica becauseNOT FOR the bubbles SALE record OR DISTRIBUTIONthe composition of have affected—and still affect—humankind, from our ancient atmospheres. As the use of fossil fuels has in- evolutionary beginnings through the origins of ancient creased, so too has Earth’s average surface temperature, settlements and civilizations, and perhaps their col- so that the greenhouse effect is no longer considered © Jones & Bartlettlapse, right Learning, up to the LLCpresent (refer to this chapter’s© Jones by most& Bartlett scientists Learning, to be purely LLC natural. As far as scien- NOT FOR SALEfrontispiece). OR DISTRIBUTION Humans have now begun to affect Earth’sNOT FORtists canSALE tell, ORthe warmingDISTRIBUTION will continue through the 4 CHAPTER 1 © Jones & Bartlett Learning, LLC. NOT FOR SALE OR DISTRIBUTION. © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC 800 NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION 700 History Projections 600 500 World energy consumption © Jones400 & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION 300 Quadrillion BTU 200 100 © Jones & Bartlett 0Learning, LLC © Jones & Bartlett Learning, LLC 1970 1975 1980 1985 1990 1995 2000 2005 2010 2015 2020 2025 2030 NOT FOR SALE OR DISTRIBUTION Year NOT FOR SALE OR DISTRIBUTION BTU = British thermal unit. FIGURE 1.2 Historical and projected trends of world energy consumption. [Adapted from: the United States Department of Energy, Energy Information Administration, International Energy Annual, 2002, 2003 (May–July 2005), 2005 and System for the Analysis of Global Energy Markets, 2005 and 2006.] © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION (a) Total reflected 3% © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC CO2 Water vapor NOT FOR SALE21% OR DISTRIBUTION NOT FOR SALE ORCH4 DISTRIBUTION Reflected 1–2% Absorbed NO from clouds 5% 2 by plants Reflected Heat 67% Heat from dust Heat Heat © Jones & Bartlett Learning, LLC Heat © Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION 6% Reflected from Absorbed by air, water, soil, air, land, and water and vegetation converted to heat © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC (b) NOT FOR SALE OR DISTRIBUTION (c) NOT FOR SALE OR DISTRIBUTION FIGURE 1.3 (a) How a greenhouse works. Solar energy penetrates through the glass and is reflected by the floor of the greenhouse as infrared radiation. The infrared radiation is trapped by the glass ceiling and warms the interior of the greenhouse. (b) The atmospheric greenhouse effect works in the same way. Atmospheric carbon dioxide acts like the glass ceiling of the greenhouse by trapping solar energy that has been reflected by (c) the Earth’s surface as infrared radiation; this warms the atmosphere. © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION Introduction: How Do We Study Earth’s Systems? 5 © Jones & Bartlett Learning, LLC. NOT FOR SALE OR DISTRIBUTION. © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC NOT FOR SALE OR
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