SWES 210 1st Edition Final Exam Study GuideChap 20 – conventional energy-What are the alternatives to fossil fuels? What direction should we go?Natural gas-What are the advantages and disadvantages of nuclear energy for commercial power plants?Advantages= no CO2 emissions, no problems with intermittencyDisadvantages= radioactive waste storage, meltdowns (cherenobyl and fukushima)-What percentage of the electricity in the US is produced from nuclear power?20%-What percentage of France’s electricity comes from nuclear power?76%-How many nuclear power plants are there worldwide? How many in the US?Worldwide= 436In US= 1/4th of them-How is the nuclear power industry changing in China?Has some of the worlds most advanced nuclear reactors, have a great increase in constructions of them. China has become largly self sufficient in reactor design and constrution.-Describe how uranium ore is processed into nuclear fuel.Extracted by open pit mines. Uranium ore crushed into fine powder and processed into yellowcake. This yellowcake is then converted to gas and centrifuged to produceuranium fuel pellets. These fuel pellets are packed into rods which are then packed into assemblines. 3,000 assemblies make up one reactor core.-How much of the nuclear fuel rod is actually “burned” or used during the time the rod is in the reactor?4%-What is the difference in abundance between U238 and U235 in natural systems and in a nuclear fuel prepared for use in a nuclear power plant?U235= is fissleU238 is not (unless fast neutrons in breeder reactors)-What is an open fuel cycle (in terms of nuclear power)?Fuel is not completely used upWhat are some of the proposed necessary improvements to nuclear power industry (fuel and plant design) to make it a viable energy alternative for the future?Do we need nuclear power? If not, what should we replace it with?No, we can replace it with hydroelectric power, biomass, and wind powerWhat is currently done with nuclear waste? Stored until it can decayWhat is a Generation IV nuclear power plant?Plants that reuse their waste and are the most efficient and sustainableWhat kind of reactor does Kirk Sorenson think we should move towards?Biofuels/BiomassWhat is the fuel in a biomass power plant? (the word biomass does not count)Burn crops (produced through agriculture) to produce heat. Ethanol from corn, biodiesalWhat kinds of biofuels are produced from fats and lipids?Bio diesalWhat biofuel is produced from sugar?EthanolWhat are the sugar sources?Corn and sugar caneWhat is the difference between say corn or sugarcane and cellulosic materials in biofuel production?Cellulostic materials are harder to break down (require more energy), and serve as no competition with food supplyWhat are cellulosic biofuel materials?SwitchgrassWhat are some difficulties with ethanol from corn as a biofuel?Competes with food and can drive up food prices. It can impact the ecosystem (pesticides, fertilizers, irrigation) and takes up land that could be left unfarmed. Causes deforestation, erosion, and desertificationCan cars run on 100% ethanol?YesWhat does E-85 mean at a gas station?85% ethanol, 15% gasolineWhat does B20 mean at a gas station?20% biodiesalWhat is an advantage of biofuels over fossil fuels in terms of CO2 emissions?Fuel economy is good, therefore less gas is needed= reduces emissions Is bioenergy carbon neutral?YesWhich two countries dominate in ethanol biofuel production?Brazil and SweadenDifferentiate between corn based (the food) ethanol, cellulosic based ethanol and biodiesel.Biodiesel comes from fats (vegetable oils, cooking grease, palm oil, animal fats, or algae). Cellulosic-based ethanol requires more energy to break down into sugar which makes it more difficult to be processed, however, it is a better alternative. Corn based ethanol is easiest to break down.Key Concepts for Chapter 17-Atmospheric Sciences1. Atmospherea. What are the four layers?Troposphere, stratosphere, mesosphere, thermosphereb. What are some of the functions (ecosystem services) of the atmosphere as discussed in class? Moderates climates, provides us with oxygen, absorbs hazardous solar radiation, burns up incoming meteors, transports and recyles water and nutrientsc. What are the main chemical constituents of the atmosphere (composition)? Carbon dioxide, nitrogen, carbon monoxide, hydrogend. How has the composition changed to what it is now from billions of years ago? Through autotrophic microbes that photosynthesized and thus produced oxygen in our atmospheree. How does the temperature vary within each layer of the atmosphere as a function of distance from the Earth’s surface? Decreases in troposphere, increases in stratosphere, decreases in mesosphere, and increases in thermosphere. Why does the temperature increase as you move away from the Earth in some cases and why does it decrease in other cases?f. Know characteristics of each layer:i. Troposphere= where weather happensii. Stratosphere= ozoneiii. Mesosphere= outer layersiv. Thermosphere= very outer layer2. Properties of Aira. Atmospheric pressure, relative humidity and temperaturei. Atmosphereic pressure= measures force per unit area produced by a column of air. b. Why does atmospheric pressure decrease with altitude? Decreases with altitude because there are less gas molecules at higher altitudesc. Why is our body sensitive to changes in relative humidity? When humidity is high, sweat evaporates slowly taking the body longer to coold. What are two causes for the temperature variation around the globe?i. Suns rays stick at varying anglesii. Tilt of earths axis gives seasons as direct/ indirect sunlight hits the surfacee. What are the properties used to classify air masses?i. humidity1. Humid= maritime air masses (form over oceans as water evaporates)2. Dry= continental air masses (form over land)ii. Temperature1. WARM tropical air masses form within tropics OR equatorial air masses for directly over equator. BOTH have LOW air pressure2. COLD polar air masses from north of 50N latitude and south of 50S latitude OR arctic air masses form in arctic’s. BOTH have HIGH air pressureiii. All air masses are either maritime or continental 3. Weather-driven by air circulationsa. What initiates all air circulation? How?i. Solar energy powers air circulations by unevenly heating the earth’s surface and causing air to rise and fall. this is