2. The Changing Global EnvironmentFigure 2.2, Plate TectonicsFigure 2.3, Global Tectonic PlatesGeology & Human Settlement: A Restless EarthSlide 5Figure 2.7, Global Earthquakes and VolcanoesClimate ChangeFigure 2.11: Global Pressure SystemsClimateTable 2.1 (3rd edn): the World’s Major CO2 PollutersTable 2.1 (4th edn): the World’s Major CO2 PollutersWater on Earth: A Scarce & Polluted ResourceHuman Impacts on Plants & AnimalsFigure 2.19: World BioregionsFood resources: environment, diversity, globalizationWorld Population & Grain ProductionGrain for people vs grain for biofuelsThe next 50 years in energy (“this is your life” part 1)PowerPoint PresentationThe next 50 years in the environment (“this is your life” part 2)Books worth reading2. The Changing Global EnvironmentGeological Base; Climate & Climate Change; Water; Human Impacts on Plants & Animals; Food ResourcesFigure 2.2, Plate TectonicsFigure 2.3, Global Tectonic PlatesGeology & Human Settlement: A Restless Earth•Plate Tectonics/Continental Drift•Break-up of Africa centered supercontinent Pangaea c. 250 million yrs Before Present (BP)•Formation of Tethys Sea•Removal of Australia from main evolutionary line in Pangaea and around Tethys Sea•Removal and return of India to create Himalayan Mountain Range•Formation of major fold mountain ranges along leading edges of North and South American Plates•At human scale, problems of earthquakes and volcanic activity along plate boundaries•Plate Tectonic Theory confirms Evolutionary Theory•Collapse of Reptiles as dominant species c. 65 million years BP, probably because of impact of asteroid in Yucatan peninsulaFigure 2.3, Global Tectonic PlatesFigure 2.7, Global Earthquakes and VolcanoesClimate Change•Climate change: natural, anthropogenic, or both?•Glacial, interglacial, & interstadial climates•Natural change--a historic pattern of 400 to 600 years interval for the past 2,000 years?•Evidence for change (the church & wine production in Europe).•Shift in North Atlantic Drift•Rice cultivation in China•Deforestation in Europe•Recent anthropogenic change•Burning hydrocarbons produces carbon dioxide. CO2 main contributor to Global Warming (Table 2.1)•Large scale CO2 production began late 1770s w/Industrial Revolution & coal burning•Modern CO2 production largely from automobile fleet•Only EU has attempted to mitigate automobile CO2 outputFigure 2.11: Global Pressure SystemsClimate•Planetary heat transfer from Equatorial to Polar regions•Planet takes in more solar radiation between Tropics of Cancer and Capricorn than it loses, loses more from Polar regions than is coming in (see Fig. 2.1)•Hot air and water masses move polewards, cold air and water returns toward Equator•Planetary heat transfer & us•Warms west coasts of continental masses•W. Europe main beneficiary•Provided main power source (wind) for planetary movement (ships) from late 1400s to mid-1800sTable 2.1 (3rd edn): the World’s Major CO2 PollutersTable 2.1 (4th edn): the World’s Major CO2 PollutersWater on Earth: A Scarce & Polluted Resource•Only 3% of world’s water is fresh water, most of it is ice, & there is rarely enough where humans want it! •Except when it floods. Floods cause more fatalities than any other natural disaster. Too many people live in flood prone regions (e.g. Bangladesh) •Much water is polluted & runoff has been increased by deforestation•Water more valuable than oil•Most destructive use of water is in agriculture (evaporation)•Use in closed systems (water for sewage disposal, washing etc.) allows recycling (tho at some cost)•When there is water policy it tends to underprice water•Texas had no comprehensive water plan until Senate Bill 2 took effect 9/1/2001Human Impacts on Plants & Animals•For most of human history we collected and hunted food•C. 20,000 BP Agricultural Revolution (AR) improved food supply, but still erratic. Protein, inputs dropped. AR encouraged human crowding (bad for health-poor waste disposal etc.) Food surplus made urban life & civilization possible, allowed division of labor, elites•Population rose rapidly, then leveled off•AR Plants chosen for productivity, ease of cultivation•Animal resources added later to do work, for protein, & for fiber•Organic Society marked by 3Fs. Food, Fiber, Fuel all grown in Organic Society•Land resources allocated between 3Fs according to population pressure, environmental needs etc.•Humans lived on, at best, c. 3 million cals. each per yearFigure 2.19: World BioregionsFood resources: environment, diversity, globalization•Industrial Revolution c. 200 years BP transformed human societies and economies•Better transport made food supply much more reliable•Better public health began inexorable increase in human life expectancy•Fossil fuel inputs took fuel out of 3F equation, then fiber, thus more land for food•Population skyrocketed, in part because of more reliable food supply (remember that deaths drop before births in classical version of Demographic Transition-DR)•Global population currently showing signs of reduced rates of increase (i.e. reaching stage 3 of DR)•Fossil fuel inputs to food now immense in developed world (10 calories in, 1 cal vegetable energy out: 10 cals vegetable energy in, 1 cal beef protein out)•Calorie consumption per head in America now c. 100 million calories per year•Rest of developed world much lower (Germany c. 40, Japan below 30)•LDCs starting to catch up very quickly in consumption (remember increase in China’s CO2 output)World Population & Grain ProductionGrain for people vs grain for biofuels•World grain supply only just keeping pace w/world population growth•North America and EU are world’s only large scale exporters of grain•Grain in NA, EU requires high fossil energy inputs•Public policy in US has reduced world grain supply by diverting corn to biofuel production, causing sharp rises in grain prices•Biofuels from food grains actually have negative impact (more calories in than calories out) as well as other negatives (increase in greenhouse gasses)The next 50 years in energy (“this is your life” part 1)•Serious and accelerating climate change (now looks fundamentally irreversible, although better public policy could reduce impact)•“Short” term energy crisis (likely to see 30 years of steadily rising prices and accelerating demands for efficiencies in usage of fossil