EnSci Final Exam
Which of the following is an effect of climate change already happening in Iowa?
An increase in annual precipitation
Imagine that a coal-fired power plant has the option to buy either a lignite coal with 5% sulfur content or a bituminous coal with 2% sulfur content. Assuming both types of coal have the same price, which type of coal would be preferred by the power plant operators? Why?
The bituminous coal with 2% sulfur content would be preferred, because it has a higher energy density. Less effort and expense would be required to reduce sulfur emissions from the power plant once the coal was burned.
As developing nations continue to experience economic growth, we should expect to see growth in global energy consumption. Which of the following energy resources has been preferentially used by developing nations to generate electricity?
Coal
Which of the following terms is defined as the connectivity between open spaces (i.e., pores) in rock?
Permeability
How do photovoltaic (PV) cells work?
Photons can "excite" or "eject" electrons from N-type semiconductor to P-type semiconductor generating unidirectional flow of electrical charge (DC) in attached conducting material
Choose the option that best completes the following sentence: Anthropogenic oil spills have a detrimental impact on wildlife and ecosystems by ________ .
Releasing carcinogenic materials, like PAHs, into the environment.
What are relief wells in the context of well blowouts?
Relief wells are drilled to intercept and seal a production well that has lost pressure control.
What is the intermittency problem with wind energy?
Wind energy can be intermittent or unpredictable in comparison to the predictability of electrical demand
What is compressed air storage? What is the benefit?
Wind energy during non-peak hours used to power compressor and pump air into underground chamber (e.g., salt cavern, exhausted aquifers, etc) Released air is reheated by recuperator, mixed with fossil fuel, and combusted to turn generator turbine Significant reduction in the amount of natural gas burned at the power plant (up to 66% less
What are mature fine tailings in the context of oil sand extraction?
a mixture of high salinity water, fine-grained sediment, and unrecovered bitumen
What was an impact of the Three Mile Island disaster of 1979?
a nearly 30 year moratorium on construction of new nuclear power plants
Under geoengineering, examples of solar radiation management and carbon cycle management, respectively, are
atmospheric aerosols and ocean fertilization
In the context of photochemical smog, if the _______________ is lower than the rate at which a mass of polluted air _______________, the polluted air will stop rising and stay concentrated over a city.
atmospheric lapse rate; loses heat with altitude
Which two forms of renewable energy dominated renewable electrical generation in 2021?
solar power & hydroelectric
Temperature control was lost at two stages during the Fukushima Daiichi nuclear power plant disaster in 2011. First,________ cut primary power to the cooling system. Second, the back-up generators for the cooling system _______
the Tohoku earthquake were flooded by a tsunami
Corexit, the dispersant chemical used in the Deepwater Horizon clean up, was found to be moderately toxic, because it facilitated __________ the tissue of aquatic organisms.
the absorption of small hydrocarbon particles into
Treating frac wastewater at municipal wastewater treatment plants was determined to be insufficient because ________ .
the effluent from the treatment plants deposited naturally-occurring radioactive material in stream sediment.
What are rare earth elements (REE)? What are they used for wind power technology?
- Lanthanum (La), Neodymium (Nd), Dysprosium (Dy) -Rare earth elements are used to produce small, yet power batteries and magnets for electronics and green technology
Under current and future climate change, _______ water in high latitude oceans ________ , decreasing the transport of carbon into the deep ocean reservoir.
warmer weaken ocean convection currents
What are common elements of the "not in my backyard" opposition to wind power?
- Noise Pollution - Aesthetic Pollution - Lower property values -Fear of eminent domain
Birds, bats, and wind turbines: What is the connection?
-140,000 - 328,000 birds die each year from collisions with wind turbines -600,000 to 800,000 bats die each year from encounters with wind turbines -Low pressure localized to blades causes rapid expansion of lung tissues and rupturing of capillaries (lung explosion)
Longwall coal mining causes sinking, or subsidence, of the ground surface above the mine. Which of the following is a negative consequence of this subsidence?
-Crops grown above the mine can more easily flood due to their lower elevation. -Roads above a longwall mine may become gradually deformed over time and require additional maintenance. -Buildings built above or near the mines may develop damaged foundations.
What are common environmental issues of geothermal electricity
-High Water Demand in Water Stressed Areas -Induced seismicity -Land Use and NIMBY issue
How does average solar insolation and irradiance of an area impact its ability to produce electricity via solar power?
-Solar irradiance = rate of energy (power) received per unit area (W/m2 ) -Solar insolation = amount of energy received per unit area (kWh/m2 ) Average insolation per day = 5.7 kWh/m2 /day = average irradiance = 239 W/m2 Insolation/irradiance varies with latitude and cloud cover (humidity)
What are the general environmental hazards of mining REEs?
-Uses toxic chemicals
What are the general environmental issues of solar power?
1) Occupy large land area, impacting desert wildlife 2) Water usage for cooling and steam production (CSP) 3) PV manufacturing (green?) - Silicon doped with heavy metals - Gallium arsenide & cadmium selenide semiconductors 4) Carbon debt (land use change & installation CO2 emissions) 5) Energy payback time >2 yrs
Recall our discussion of the power density of a solar photovoltaic array. The efficiency of a solar array is the proportion of solar energy that is converted to electricity. If an area of land receives solar energy at a rate of 200 W/m2 and the efficiency of the solar array is 15%, what is the expected power density of the solar array?
30 W/m2
What percentage of U.S. energy (i.e., total energy consumption) was derived from fossil fuels in 2020?
75-84%
Given that the Earth's surface encounters incoming solar radiation at a rate of 184 W/m2 and, on average, reflects 12% back into outer space, what is the average emissivity of Earth's surface?
88% or 0.88
What are the minimal average wind speeds for utility-scale wind power?
> 6.4 m/s or 14.3 mph is optimal for wind energy
Which of the following coals experienced the highest intensity of burial diagenesis?
A bituminous coal that is 300 million years old.
Which of the following options correctly explains why more progress has been made in reducing sulfuric acid deposition relative to nitric acid deposition?
A large proportion of sulfur emissions are derived from point source emitters, like power plants. The Clean Air Act Amendments were more effective at reducing emissions from point source emitters than non-point source emitters of NOx compounds.
Which of the following best describes the meaning of social sustainability at a national scale?
A nation that provides a good quality of life (e.g., education, health, and equality) for current citizens and future generations.
Boreal forests are being cleared for expansion of oil sand mining in Alberta, Canada. Which of the following statements correctly describes an environmental impact of clearing boreal forests?
ALL
Which of the following correctly lists a human or mechanical error that contributed to the Macondo Well blowout and the 2010 Deepwater Horizon spill?
ALL
What are proxy data in the context of studying Earth's ancient climate?
ALL -Climate data derived from sources such as plankton and stable isotopes. -Measurements taken from natural recorders of Earth's climate in the past -Data interpreted from our understanding of how climate change impacts chemical, physical, and biological processes
Which of the following is TRUE about wastewater related to conventional and unconventional hydrocarbon production?
ALL -Wastewater from conventional and hydraulic fracturing production can be recycled for secondary phase recovery and future frack treatments (i.e., stimulations). -Produced water can have a salt content that exceeds that of seawater by 10,000 times. -Disposal of waste water underground is regulated by the Safe Drinking Water Act
Choose the option that correctly explains why the following statement is FALSE. Combustion of sulfur-bearing organic compounds in coal is the primary source of acid mine drainage.
Acid mine drainage is primarily caused by oxidation of sulfur-bearing, inorganic minerals that are exposed at mining sites.
The assigned reading from the American Geological Institute entitled "Coal Mining and the Environment" discusses several ways that acid mine drainage can be treated. Which of the following is one of the methods discussed in the reading?
Add neutralizing materials, such as pulverized limestone, to streams affected by acid mine drainage.
Choose the option that best completes the following statement. Enhanced chemical weathering using olivine minerals may involve __________ .
All -Releasing pulverized olivine in the ocean to react with dissolved CO2. -Expanding current olivine mining efforts by 12,500 times. -Pumping CO2-enriched solutions down into subsurface olivine-bearing rocks.
What is a "well blowout"?
An uncontrolled release of hydrocarbons due to loss of pressure control at the production site.
As developing nations continue to experience economic growth, we should expect to see growth in global energy consumption. Which of the following regions has contributed the most to growth in global energy consumption in the past 30 years?
Asia
What is band gap energy? How does it affect the efficiency of a PV cell?
Band-gap energy = minimal energy needed to "eject" electron Band-gap energy of silicon corresponds to wavelengths in near infrared range of spectrum → ¼ of solar radiation too long to create electrical current
Biofuels provide both positive and negative impacts on human health and environmental conditions. Briefly describe one way that production and/or consumption of biofuels may have a positive impact, relative to fossil fuels. (2 points) Briefly describe one way that production and/or consumption of biofuels may have a negative impact, relative to fossil fuels. (2 points)
Biofuels have a positive impact, relative to fossil fuels in several areas. One of which is that biofuels release less carbon monoxide to the environment than fossil fuels. An area in which biofuels have a negative impact in comparison to fossil fuels, is that biofuels result in a greater use of nitrogenous fertilizers which releases the harmful NOx compounds to the environment. Producing the crops needed for biofuels can also cause water stress on the areas that grow the crops.
What is the relationship between concentration ratio and energy efficiency of CSP?
CSP systems characterized by concentration ratio = ratio of concentrated sunlight to direct sunlight
From which country does the United States derive most of its oil imports?
Canada
Which of the following are TRUE regarding the transportation of dilbit crude?
Companies do not need to invest in syncrude upgrading facilities before transporting dilbit by either rail or pipeline.
When estimating power density of a coal power plant in lecture, the power plant's electrical capacity was 1 gigawatt (GW) whereas its thermal capacity was 3 GW. Why is the thermal capacity of a power plant always higher than its electrical capacity?
Converting thermal energy to mechanical and electrical energy is an inefficient process. A large proportion of heat produced by burning a fuel is lost to the environment as waste heat.
What is the potential for expanding hydropower in the U.S.?
Current locks/dams on the Mississippi, Ohio, Alabama, and Arkansa rivers → 8 GW capacity Compare to the installed capacity at the Grand Coulee Dam, WA → 6.8 GW
What are the major components of impoundment hydropower systems?
Dam + reservoir creates a steady supply of water for generating electricity Electrical capacity is proportional to discharge (volume/time) and head (vertical drop of water)
How do deposition and erosion limit the life spans of dams and impoundments?
Decrease river velocity behind dam increases sedimentation rates while eddies at front increase erosion rates → finite lifespan of dam and reservoir (consider average age of large dams in US: 56 years
Domestic drinking water wells in northeastern Pennsylvania were contaminated with methane in 2007-2009, coincident with the expansion of hydraulic fracturing operations in the area. Which of the following statements explains the link between methane contamination and hydraulic fracturing (HF) in this context?
Drilling of HF wells disturbed shallow sources of methane. Then, improperly abandoned wells acted as migration pathways that connected the methane source and drinkable groundwater.
What are general pros and cons of the three processes used to currently generate electricity via geothermal resources?
Dry Steam Process:•Rare conditions •Expected decline in steam production •Waste-water disposal Flash Steam Process: •Most common •Change in pressure leads to flash boiling •Separation stage(s) decrease efficiency Binary Process: •Heat transferred to working fluid with lower boiling temperature •Isopentane (28°C) •Lowest efficiency but more sustainable
What are enhanced geothermal systems?
EGS involve artificially creating hydrothermal flow by: • Hydraulically fracturing subsurface rocks (increase permeability) • Regularly inject water to maintain reservoir volumes and pressures
How does a concentrated solar power (CSP) system produce electricity?
Effectively concentrates irradiance into smaller area to run heat engine CSP systems characterized by concentration ratio = ratio of concentrated sunlight to direct sunlight
What is pumped storage hydropower?
Excess electrical generation during times of low demand used to pump water to higher elevation basins or reservoirs
Corexit 9500 is a chemical solution used extensively during the clean-up of the Deepwater Horizon oil spill in 2010. What was the purpose of applying Corexit 9500? (1 point) Was Corexit 9500 effective? Explain your reasoning (3 points)
Experiment results showed that bacterial productivity and metabolism of hydrocarbons decreased in the presence of Corexit, indicating that the efficacy may have been low.
Carbon monoxide (CO) results from incomplete combustion of fossil fuels due to presence of excess oxygen.
False
In one of our lectures, we used a simple two layer model of the Earth to test the hypothesis that modern global warming is due to an enhanced greenhouse effect. The hypothesis was supported by the observation that the stratosphere is warming at the same rate as the lower troposphere.
False
NOx compounds form when nitrogen-bearing compounds in fossil fuels completely oxidize during combustion.
False
Which of the following options is not a common frac fluid additive?
Gels that thicken frac fluid to better transport proppant.
There are many economic risks of not reducing fossil fuel consumption in regional and global energy systems.Which of the following options is NOT one of these risks?
Gradual decline in energy returned on investment (EROI) of nuclear and renewables.
Which of the following explains the gaps in the infrared emission spectrum (i.e., transmissivity spectrum) of the Earth?
Greenhouse gases, such as water vapor, ozone, and CO2, absorb significant amount of energy at those infrared wavelengths.
If Hypothesis 1 is that enhanced greenhouse conditions caused the observed 1oC increase in the surface temperature, which two parameters above should be modified to test this hypothesis? (1 point). If Hypothesis 2 is that an increase in solar radiation caused the observed 1oC increase in the surface temperature, which two parameters above should be modified to test this hypothesis? (1 point).
Hypothesis 1 - need to modify emissivity of the atmosphere and the surface temperature. We modify the greenhouse effect by increasing the proportion of infrared radiation absorbed and re-emitted by the atmosphere. We also need to increase the surface temp by 1 degree Celsius to match empirical measurements. Hypothesis 2 - modify P-out and temperature of the surface. Again, need to increase surface temp to match measurement. The energy budget of our planet must be balanced (P-in = P-out). So, if the rate of incoming solar radiation increase (P-in), then P-out must increase, too.
Which of the following provides a detailed record of Earth's climate over the past 800,000 years?
Ice cores from Antarctic ice sheets
Hydrocarbons produced via hydraulic fracturing and oil sand extraction are considered unconventional hydrocarbons derived from unconventional hydrocarbon systems. Why are they considered "unconventional"? Be specific. (2 points) Describe a difference in the environmental impacts of hydraulic fracturing and oil sand extraction (2 points).
In in oil sand deposits, the seal rock allowed lighter hydrocarbons to seep upwards, leaving only the denser, relatively immobile hydrocarbons in place. Improper waste water treatment can be an environmental problem for both HF resources and oil sands.
What is the most likely direct cause for the increase in the number of 3.0 magnitude earthquakes in the U.S. (i.e., 100+ events per year after the year 2000)?
Increase in wastewater disposal well injections
In the context of ocean fertilization, a form of geoengineering, what is the purpose of seeding the ocean with soluble iron? Choose the option that best answers t
Iron is a limited nutrient in the ocean. Adding iron may increase photosynthetic productivity and remove carbon from the atmosphere at a higher rate.
Which of the following options is NOT a unit of power?
Kilowatt-hour (kWh)
Why has there been limited development of geothermal electricity?
Large upfront expenses to ensure adequate resource Compare $3000 - 5000/kW geothermal vs $900/kW natural gas
How do line focus (e.g., trough concentrators) CSP systems work? Point focus systems?
Line focus systems (troughs) typically have lower concentration ratios than point focus systems (power towers & dish systems)
The majority of cases of hydrocarbon contamination in marine environments during oil exploration and extraction can be attributed to what?
Loss of pressure control at the well or borehole (i.e., well blowout).
Which of the following contributes to the substantial reclamation debt of oil sand operations in Alberta, Canada?
Mature fine tailings in impoundments can take 30 years or more to settle out of wastewater.
Which of the following options is not a method for preventing explosions in underground coal mines?
Minimizing the concentration of rock dust (pulverized limestone) in the mine shafts
Which of the following options explains why sulfate (SO42-) concentration can be used as a proxy for extent of coal mining in a watershed?
More coal mining = an increase in activity of anaerobic bacteria. The anaerobic bacteria produce hydrogen sulfide waste that oxidizes into dissolved sulfate.
Describe at least one of the hazards of MTM/VF. Frame your discussion as a process starting with the human action that initiates the environmental hazard and ending with how aquatic organisms are affected by it.
Mountaintop removal mining + valley fill technique is when coal seams are mined from a mountain top and the overburden is put in the adjacent stream valley. This act means the land is not returned to it's original landscape after the mining job is completed, this can cause issues with the land such as flooding. Another big issue is is acid mine drainage which can get into water supplies and affect the local aquatic organisms. The way this affects aquatic organisms is called bioaccumulation. As toxic chemicals from the mine, such as selenium, enter the water it is absorbed by the local organisms. They start with a small amount, but as they have offsprings, and their offsprings have offsprings more selenium is present each time. This happens until eventually the toxic threshold is reached and the organisms die. Other organisms can be affected by eating the previously affected organisms as well.
Emissions of some airborne pollutants are reduced during the production or use of biofuels, as compared to gasoline, but not all. Which of the following pollutants are NOT reduced when producing and/or using biofuel blends?
NOx compounds
Which of the following energy resources has the highest energy density?
Natural Gas
What is the largest contributor to hydrocarbons "leaked" into the oceans?
Natural seeps
Which of the following is a difference between point source and nonpoint source emitters of airborne pollution?
Nonpoint source emitters are widely distributed while point source emitters are localized.
Describe one way that nuclear power may be better for human health or environmental conditions than coal. (2 points) Describe one way that nuclear power may be worse for human health or environmental conditions than coal. (2 points)
Nuclear power may be better for human health or environmental conditions than coal, because there are little to no air pollutants that are released from nuclear power plants. Air pollutants such as CO2 and sulfuric pollutants are harmful to human health and increase the rate of climate change. Nuclear power may be worse for human health or environmental conditions than coal because it does produce radioactive waste and a disaster at a nuclear power plant can cause health issues (from the radiation released) for the global population. Radioactive waste is difficult to store, normally it is cooled in cooling pools and then transferred to dry casks to reduce radiation emissions, but that is only a short-term solution. Radioactive waste is dangerous to humans and the environment if released.
Which of the following describes a difference between a nuclear power plant and a coal burning power plant?
Nuclear power plants do not require emission control mechanisms, like ash filters and electrostatic precipitators.
Which of the following is (are) evidence used in class to argue that natural climate forcings are not responsible for modern global warming?
Observed modern warming of 1°C per century is 2-5 orders of magnitude faster than temperature change associated with tectonic forcing.
Choose the option that best completes the following statement. The temperature and pressure conditions between 3 and 6 km depth that produce hydrocarbons are termed the _______ .
Oil window
Which of the following statements is TRUE about the response to the Deepwater Horizon spill?
Only 25% (1.25 million barrels) of the oil released is currently accounted for.
Which of the following describes an advantage of burning municipal solid waste (MSW) to generate electricity?
Only the ash is sent to a landfill. Reducing landfill use by 85%.
Choose the option that best completes the following statement. Under increasing heat and pressure, the formation of conventional hydrocarbons proceeds in a prescribed order as follows ________ .
Organic remains, kerogen, oil, natural gas
What is the benefit of pumped storage?
Overall, net consumer of energy that makes generation of electricity more economical > 120,000 MW installed capacity worldwide Additional storage option for intermittent wind energy
Which of the following correctly lists a fossil fuel-derived airborne pollutant and its corresponding impact on human health?
PM2.5; atherosclerosis and other cardiovascular diseases
Which of the following correctly describes a process through which carbon is removed from the atmosphere and stored in the lithosphere carbon reservoir?
Precipitation with dissolved carbonic acid chemically weathers silicate minerals exposed at the surface.
Which of the following units describes the largest quantity of energy?
Quad (Q)
What is a trap/seal in the context of conventional hydrocarbon systems?
Rock layers with a particular geometry that keep a large volume of hydrocarbons locally concentrated and prevents the hydrocarbons from seeping to the surface.
In parts of the country where areas of photochemical smog often occurs, why does the peak concentration of ozone (O3) occur in the afternoon between noon and 3 pm?
Solar UV radiation is necessary to produce ozone, and the sun is highest on the horizon during the early afternoon.
How do temperature and salinity differ upstream and downstream of a dam?
Substantial temperature and salinity differences between reservoir and upstream portions of river → further fragmentation of river habitat
Which of the following statements is FALSE regarding the importance of plate tectonic processes and energy resources?
Tectonic stresses cause subsidence. Subsidence causes organic material to become buried in the crust where it is transformed into fossil fuels.
What three general requirements are necessary to produce electricity from a geothermal resource?
Temps in excess of 90°C, hydrothermal fluids, permeable rocks
What are the 3 major reservoirs of carbon besides the atmosphere?
Terrestrial plants/soil, the deep ocean, and the lithosphere
Which of the following is not a relevant factor when estimating the power density of a coal-fired power plant?
The area of the wetland that produce peat in the geologic past.
What information can be directly measured from bubbles in ice cores?
The atmospheric concentration of carbon dioxide in Earth's past
During the enhanced oil recovery process (EOR), what is the purpose of pumping carbon dioxide, steam, and liquid water into a conventional oil reservoir?
The carbon dioxide and steam lower the viscosity and surface tension of the remaining oil in the reservoir. The liquid water drives the oil into a production well.
Examine the PIT results of a newly completed (hypothetical) production well in the graph above. Which of the following options describes a correct interpretation of the PIT results?
The casing and cement of the well are intact, because the observed leak-off pressure matches the expected leak-off pressure.
Why did the 2010 Kalamazoo River dilbit spill require two phases of clean-up?
The first phase of the clean-up primarily removed the low-density diluent. A second phase of dredging river sediment was necessary to remove settled, high-density bitumen.
How did the moderator at the Chernobyl Nuclear Power Plant contribute to the release of radioactive material during the disaster?
The graphite moderator ignited, sending a plume of radioactive material high into the atmosphere.
When hydrocarbons "leak" into the ocean, either at natural seeps or due to anthropogenic spills, what is the expected fate of the heavy, tar-like hydrocarbons?
The heavy hydrocarbons will be incorporated into the sediment on the seafloor.
What carbon reservoir has the largest capacity for storing atmospheric carbon?
The lithosphere
Which of the statements below correctly describes the impact of acid deposition on biodiversity in freshwater ecosystems?
The lower pH preferentially kills or decreases the productivity of nutrient-rich plankton. The loss of productivity at lower levels of the food web cascades throughout the ecosystem decreasing biodiversity at all levels of the food web.
Which of the following describes a decision made during construction of the Fukushima Daiichi power plant that made it more susceptible to tsunamis?
The natural seawall was reduced in elevation to facilitate ocean delivery of heavy equipment and prefab modules.
What happens to the overburden at surface coal mines, like open pit mines and mountaintop removal mines?
The overburden at an open pit mine is typically used to back fill mining pits and return the landscape to its approximate original contours (i.e., original topography). The overburden at a mountain top removal mine is placed in adjacent stream valleys, resulting in a lower relief landscape.
Steam assisted gravity drainage (SAGD), a form of in situ oil sand production, was found to generate more carbon dioxide emissions than ex situ bitumen mining. Which of the following statements correctly explains the greater carbon emissions of SAGD?
The poor quality of the bitumen recovered from SAGD requires mandatory upgrading to synthetic crude oil, a process that requires 2000 cubic feet of natural gas for every barrel of synthetic crude.
The process of hydraulic fracturing or "fracking" of a thermally-mature source rock is necessary to produce natural gas and oil because:
The pore spaces in the source rock are not well connected. Hydraulic fracturing will connect the pores artificially.
Which of the following conditions is necessary for the formation of peat in a wetland system?
The rate of accumulation of organic material must exceed the rate of decomposition.
Which of the following statements is TRUE regarding mountaintop removal mining + valley fill (MTM/VF) and selenium in stream water?
The water concentration of selenium within a watershed increases as more of the watershed is disturbed by MTM/VF operations.
How does water demand for oil sand production compare with water demand during conventional oil production?
The water-oil ratio (WOR) for ex situ extraction is on the low end of the conventional oil WOR range. The in situ extraction WOR may be equal to or higher than the conventional WOR range.
Oil sand products generate via ex situ or in situ techniques are indistinguishable in terms of: environmental impacts greenhouse gas emissions, and energy-returned-on-investment (EROI)."
This statement is false. In terms of the greenhouse gas emissions, in situ techniques are shown to produce more greenhouse gasses than ex situ techniques. In terms of environmental impacts, both have drawbacks but I would consider in situ to be worse due to the steam injection which can cause harmful wastewater to migrate towards drinking water or marine life and can cause earthquakes.
Changes in the characteristics of severe weather events over long time scales (e.g., decades to centuries) are evidence of climate change.
True
Converting the kinetic energy (mechanical energy) of the wind to mechanical energy in a wind turbine involves a low conversion efficiency, because of the high potential for unordered states among the innumerable and independently moving air particles in wind.
True
Data from the Multi-Ethnic Study of Atherosclerosis found that not all components of PM2.5 were associated with an increase in carotid artery thickness (CIMT). More specifically, exposure to PM2.5 components emitted by the use of fossil fuels exhibited the greatest effect on CIMT.
True
In his TED talk entitled "Magic Washing Machine", statistician Hans Rosling argues that future growth in the population and economic activity of developing countries will greatly increase global energy consumption.
True
Multiple fluids may travel upward through an oil and natural gas well and "leak" into sources of drinking water. These fluids include hydrocarbons from the reservoir rock, methane from shallow sources, and salt-rich formation water.
True
The US Environmental Protection Agency (EPA) classifies coal ash as a non-hazardous waste and has established rules for coal ash disposal similar to those for household garbage.
True
The application of bacteria, along with nitrogen- and phosphorous-based fertilizers, to oil spills in marine environments is thought to increase the biological breakdown of the hydrocarbons
True
Areas in which human activities use a significant amount of available water are called ________ .
Water stressed areas
Why is it more difficult to estimate the power density of an energy resource, like coal, than it is to estimate its energy density?
When measuring energy density, you measure the mass of coal and the amount of heat it produces when you burn it. An accurate power density estimate requires a full life cycle approach, in which one needs to evaluate all of the land used when producing and utilizing the resource.
Under what circumstances could biofuel production potentially generate a larger carbon footprint than conventional hydrocarbons?
When natural environments are converted to agricultural land for energy crops.
Does the graph above indicate any intrinsic benefit of increased energy consumption? In your answer, be sure to: describe the change in slope of the graph's trend line; correctly define "energy poverty"; and provide an example of how greater energy consumption may contribute to sustainability.
Yes, there is an intrinsic benefit of increased energy consumption for most countries. Energy poverty is defined as households lacking access to electricity or other household appliance. And many countries that have a global average energy consumption rate below the average have a population that is living in energy poverty. But you also need to follow the graphs trend line and see that not all countries with a high energy consumption also have a high SDI. If that was the case then the trend line would be increasing linearly, which it is not. If you follow the asymptote of the trend line you can see that yes, for most countries there is an intrinsic benefit to energy consumption, but as the rate of energy consumption increases, the SDI does not increase along with it. Meaning for a small sample of the countries there is not an intrinsic benefit, however this is not the case for the majority.
Expanded biofuel production under ______ scenario could potentially lead to greater ________ than predicted under RCP8 scenarios.
a RCP4.5 water stress in the United States
A recent studying combining satellite imagery, direct sampling, and oceanographic modelling indicates that oil from the Deepwater Horizon Disaster may have spread _____________________
beyond closed fisheries and contaminated other areas of the Gulf of Mexico.
Agricultural studies involving greater incorporation of organic carbon into soils reveal a ________ effect, suggesting that the terrestrial carbon reservoir may reach its capacity in the near future.
carbon saturation
There is substantial economic inertia against transitioning away from a fossil fuel-dominated energy economy in the U.S. Which of the following is NOT a contributing factor to this inertia?
comparably high EROI values for renewable energy resources
Spent nuclear fuel (i.e., nuclear waste) in the United States is stored in two stages. Spent fuel rods are temporarily stored in _______ and then transferred to _______ .
cooling pools until they sufficiently decrease in temperature and radioactivity dry casks
The amount of greenhouse gas (GHG) emissions of oil sand operations _______
depend on the extraction process and the bitumen pathway used by a company
What are the two ideal characteristics of a watershed for hydroelectric power?
flood control and irrigation
Evaporation of leachate to prevent _______is a beneficial use of _________ .
groundwater contamination burning landfill gas (biomethane) in an on-site boiler system.
Which of the following units would be best for describing the rate at which the thermal energy is converted to electrical energy?
megawatt (MW)
The historical (~1880-present) increase in atmospheric carbon dioxide concentrations is correlated with a large negative excursion in atmospheric carbon isotopes. This correlation suggests that the major source of historical carbon dioxide emissions is ________ .
organic carbon
The U.S. energy economy shows two major transitions over its history. Each transition involved _____________________.
reducing the use a lower energy density resource and increasing use of a higher energy density resource.
Choose the option that best completes the statement below. Energy transitions that are perceived to __________________________ often face significant inertia that prevent or slow large-scale evolution of energy systems.
result in riskier, unreliable energy access
The Stefan-Boltzmann Radiation Law was used in lecture to test hypotheses concerning the cause of recent global warming.Generally speaking, the Stefan-Boltzmann Law describes the relationship between the______ of an object and the_______ .
temperature rate of energy radiated from the object.
What is pore pressure?
the pressure exerted by fluids within the pores of rocks
