1AnnouncementsGraduate Homework #1 due todayReminder: First Presentations on ThursdayAi i lddi tiit•Asian monsoon in a warmer world - predictions, impactsKen LeRoy, Loren Hill• Global warming and climate extremes: hurricanesPercival Gou, Kimberly Makar•Nuclear Energy: the new green option? AStddTh BAaron Seastrand and Thomas Benson• Peak oil - what is it, has it come and gone, and why should we care? Matt Wander, Rhys Smith, Audra Antczak2Reminder: First Presentation one week from next Tuesday The assignment (see the website for details): (1) Address a question (don’t just summarize the readings)(2) Explain the issue, define the terms, be scientifically balanced(3) Explain what is known about the topic, but just as important, what the uncertainties or gaps are. (4) Stay on point (don’t get sidetracked by tangents not relevant to the question)Reminder: First Presentation one week from next Tuesday How to give a good presentation:(1) Timing is everything (don’t go over!)(2) Practice it first!(3) Simple, uncluttered slides(4)Cite your sources(4)Cite your sources(5) Use well-designed figures- simple, unambiguous titles- clearly visible axes, in large type, with units(6) Timing is everything!3Lectures on Global Change DriversI. Energy (14 Sept) II. Population and Consumption (21 Sept)III. Land Use change (Later)Why lectures on Energy, Population, Consumption, and Land use in a class on Global Change?It is clear that the future course of history will be determined by the rates at which people breed and die, by ypp,ythe rapidity with which nonrenewable resources are consumed, by the extent and speed with which agricultural production can be improved, by the rate at which the under-developed areas can industrialize, by the rapidity with which we are able to develop new resources, as well as by the extent to which we succeed in avoiding future wars. All of these factors are interlocked.Harrison Brown (1917-1986), The Challenge of Man’s Future, 1954(a book given to me by my first advisor in grad school, John Holdren)4Lectures on Global Change DriversI. Energy (14 Sept) Readings: Holdren (1991) “Population and the Energy Problem”Pop & EnvironmentEnergy Problem Pop. & EnvironmentPacala & Socolow (2004), Stabilization Wedges: solving the climate problem for the next 50 years with current technologies, ScienceII. Population and Consumption (21 Sept)Readings: Cohen (2005), “Human Population grows up”, Sci. AmericanRaupach, et al. (2007), “Drivers of accelerating CO2 emissions”, PNASGlobal Change Drivers: ENERGYI.OVERVIEW: Why a lecture on Energy in aGlobal Change Lecture #7, S. Saleska, 14-Sept-2010*I.OVERVIEW: Why a lecture on Energy in a class on Global Change? II. Sources and uses of energy in the world today III. What are the near-term possibilities for changing the energy infrastructure to fixchanging the energy infrastructure to fix Global climate change?* With thanks to Dan Kammen (UC Berkeley) and John Holdren (Harvard – now at the White House!!)5Why a lecture on Energy in a class on Global Change?Atmospheric carbon dioxideFirst: human patterns of energy-use cause global warming!Flow of energy needed to generate a unit of economicFraction of energy derived from non-renewable carbon-based forms (fossil fuels)dioxideeconomic outputforms (fossil fuels)Second: energy is the single largest component (by far!) of the global economyWhy a lecture on Energy in a class on Global Change?Third: human energy-use is a global change!Lights at night25% of global energy use?Lights from space (NASA)6Four things to come away from this lecture with:(1) Basic energy concepts/calculations(2) The relation between Energy use and economy (energy and economic growth can be decoupled)(3) The energy-economy environment dilemma:(hint: it is not that we are running out of energy)(4)Technological options for sustainable non-carbon ()gpenergy are feasible nowBrief primer on energy concepts• Energy is the ability to do work (e.g. move a itf th hdit )mass against a force through a distance)(forms: kinetic = energy of motionheat = thermal energy (molecular motion)chemical = energy of molecular bonds nuclear = energy of atomic nuclear bonds• Poweris energy per unit time (the rate at which energy is transferred or consumed)7Energy (an amount) Power (a flow)• 1 Joule (J) (SI unit, e.g. scientific lit.) Watt (J/sec)= 1 kg m2/sec2Brief primer on energy conceptsUNITSPower (energy per time = a flow)= 1 kg m2/sec2= 1 newton-meter (force x distance) (and:(energy to raise ~100g 1m high)= 0.239 calories(1 cal = energy to raise 1 gram water 1C)• Calorie (for food = 1000 cal = 1 kcal) Cal/hour (useful for exercising!) •Watt-hour, kilowatt-hourkilo-watt = 103wattsMega- 106Giga- 109tera- 1012peta- 1015exa- 1018metricWatthour, kilowatthour • British Thermal unit (Btu)= heat to raise temp. of 1 lb water by 1◦F= 1,055 Joules• Quad (quadrillion Btu = 1015Btu) Note: 1 TW  33 Quads/year Horsepower (33,000 ft-lb per minute• Tons of Oil equivalent (TOE) (or Barrels of oil) ~ 746W)• Tons of Coal equivalentenglishGetting Facile with Energy Units and Data(e.g. Homework #4!)Converting units -- the “multiply-by-one” rule:To convert units, multiply by a ratio equal to one (keeps the value the same, but changes the units). EXAMPLE: 20 km/liter = ?? miles per gallonmilitersmikm 785.32.620785.32.620galmigalgalxkmxliter9.461010118Getting Facile with Energy Units and DataA useful energy-unit calculator http://www.iea.org/Textbase/stats/unit.aspData sources on energy statisticsU.S. Gov’t Energy Information Agency (EIA): http://www.eia.doe.gov/International Atomic Energy Agency: http://www.iaea.org/DataCenter/index.htmlOrders of Magnitudein Terawatts (TW) = 1012W• Solar energy intercepted by earth: 175,000 (top of atmosph)87 000(t f )87,000 (at surface)(~ 170 W/m2)• Latent & convective heat flow fromearth’s surface to atmosphere: 50,000 (drives general circulation & weather)• Net Primary Productivity of the biosphere 100 •World energy consumption13World energy consumption13• U.S. Energy consumption 4 • Energy content of food consumed by <1 world’s human population(about 100 watts/person = 2100 Calories/personx 6 billion people = 0.6 TW)9II. What are the sources from which energy is derived, and what do we use it for?August 15, 2003: 8:15 PM10U.S. Total ~ 100 Quads ~ 3.3 TWWorld Energy