FINAL EXAM Flashcards
(202 cards)
1
Q
what are conventional fossil fuels?
A
the least expensive fuels to produce and supply nearly all of the energy provided by fossil fuels (coal, oil, natural gas)
2
Q
what are unconventional fossil fuels?
A
more expensive to produce than coal, oil, natural gas, may eventually replace FF;oil shales and tar sands
3
Q
what is the most widely used FF?
A
crude oil, then coal, natural gas
4
Q
what is traditional biomass comprised of?
A
fuelwood, charcoal, agricultural residues, animal dung
5
Q
what is the relationship between traditional biomass and agriculture?
A
its most widely used in rural areas where agriculture is the principal economic activity
6
Q
why is coal production highest in china?
A
to generate electricity, power the rapid expansion of their economy
7
Q
layers of the atmosphere in order
A
- troposphere
- stratosphere
- mesosphere
- thermosphere
8
Q
characteristics of the troposphere
A
temperature declines with higher altitude (negative correlation between temp and altitude), lapse stops sealing in earth’s atmosphere
9
Q
characteristics of the stratosphere
A
“just right” for ozone development, waste heat from ozone reactions warms temperature
10
Q
what is the role of ozone in the stratosphere?
A
ozone is essential and most abundant here, where it absorbs solar energy (UV-B) that is harmful to organisms
11
Q
describe the stratospheric cycle of ozone
A
it first forms when molecular oxygen absorbs solar energy and photodissociation occurs. ozone forms when the single oxygen atoms from photodissociation combine with molecular oxygen. the ozone gets split again when it absorbs ultraviolet radiation
12
Q
stratospheric ozone vs tropospheric ozone
A
smaller amounts of ozone in the troposphere, but still harmful to human health and ecosystems; its considered a pollutant, it combines with NO and VOCs to form photochemical smog
13
Q
how does the stability of the CFC molecule reduce stratospheric ozone
A
CFCs are inert chemicals meaning they do not break down easily and do not react with other chemicals; they eventually reach the stratosphere where the molecules are broken down by photodissociation, freeing chlorine, which causes a sequence of reactions in which a chlorine atom changes an ozone molecule into molecular oxygen, freeing the chlorine atom from chlorine monoxide, allowing that atom to destroy multiple atoms of ozone; O is also converted into O2 which reduces the amount of single oxygen atoms to form more ozone
14
Q
what is the halogen depletion hypothesis?
A
- fugitive CFCs can make their way into the atmosphere
- photodissociation frees all the chlorine atoms from the og CFC molecule
- the chlorine atom reacts with O3 and O to reduce total O3 in the stratosphere
15
Q
how was the halogen depletion hypothesis proved?
A
spy planes were turned into research vehicles equipped with special instruments and flown over the south pole where they found high concentrations of chlorine atoms in areas of low stratospheric ozone concentrations
16
Q
what were the readily available forms of replacement for CFCs?
A
HFCs
17
Q
what is lapse rate?
A
the rate at which temperature changes with altitude; raising a parcel of air will cause it to expand, thus cool
18
Q
what is adiabatic lapse rate?
A
the default; a given parcel of air in which temperature change due to compression or expansion is associated with changes in altitude, but does not exchange heat with surrounding air; abt 1 degree celcius per 100 m
19
Q
what is the process of cooling for the adiabatic lapse rate?
A
as air rises, pressure reduces, volume expands, fewer collisions between molecules occur, air cools (happens without any input)
20
Q
what happens if the observed lapse rate is faster than the adiabatic lapse rate?
A
air parcels experience **more rapid cooling **and are cooler than surrounding air at higher altitudes, which means they are more dense and will sink back towards their og location
21
Q
what happens if the observed lapse rate is slower than the adiabatic lapse rate?
A
air** does not cool** as quickly and becomes warmer than surrounding air at higher altitudes, making it less dense, meaning it can rise further and move away from its og location
22
Q
what does the southern polar vortex do?
A
traps gases (CFCs)
forms polar stratospheric clouds (where the breakdown of CFCs is accelerated
23
Q
how do the seasons affect the southern polar vortex?
A
- cold winter air forms vortex
- early spring brings increased solar radiation, photodissociation more Cl from CFCs
- in late spring, warmth returns, breaking up polar vortexes, throughout summer ozone levels increase again as polar air mixes with surroundings
24
Q
why are polar vortexes less of an issue in the north pole?
A
- land mass is unevenly distributed –> weaker vortex, trapping less air
- comparatively warmer temperatures: limiting formation of polar winds forming vortex & limiting formation of stratospheric clouds
25
how did policy solve the CFC problem?
companies agreed that if there was sufficient evidence of CFCs being harmful, they would stop/lessen production; basis of evidence found from research served for Montreal Protocol = 50% reduction in CFCs; HFCs become alternative
26
how is the CFC problem different from global anthropogenic climate change?
there were readily available alternatives, getting rid of CFCs is simpler because you can specifically eliminate specific type of refrigerants and in spray cans, not as much political lobbying passing disinformation
27
primary pollutants
enter atmosphere in form that is harmful to life & objects ex. Carbon monoxide, VOCs, NOx, SO2, aerosols
28
secondary pollutants
formed in atmosphere by interaction of primary pollutants with sunlight & other gases
ex. ozone formed by interaction of sunlight w/hydrocarbons & NOx, VOCs (benzine, formaldehyde), (secondary organic) aerosols, sulfuric acid
29
what is carbon monoxide & how are factors that contribute to its formation?
product of incomplete combustion of hydrocarbons, produced in combustion reactions where oxygen is insufficient, temp is too low, or air supply rate is too fast relative to insufficient oxygen, mixing in combustion chamber is insufficient;
30
why is carbon monoxide harmful?
binds to hemoglobin & disrupts transportation of oxygen
31
what are particulates?
solids or condensed liquids that are suspended or floating in the atmosphere; aerosols = mixtures of liquid & solid particles
ex. soot from fire
32
what are coarse particles?
PM10; between 10 and 2.5 microns; smaller than a cell, tend to settle more quickly, can be blocked by mucus and nose hairs, less dangerous
33
what are fine particles?
PM2.5
34
what are ultrafine particles?
PM0.1 below 0.1 microns, smaller than a virus, resists gravity settling but may be more likely to stick to larger particles or be deposited onto surface, exist in high concentrations closer to the surface, can be inhaled deeply and settle on lung surface leading to respiratory illness most dangerous
35
what are primary particulates?
emitted directly from some economic activity
36
what are secondary particulates?
formed by interaction of primary particulates with atmosphere
ex. nitrates
37
what is the weekend effect?
through nucleation, water droplets condense on particles, starting to form or seedling clouds. more rainfall and storm activity tends to happen toward the end of the week as a result of pollutants form work week, clouds form by weekend
38
characteristics of sulfur dioxide
sulfur aerosols form haze & clouds that reflect some sunlight --> cooling; FF combustion enhances flow of sulfur to atmosphere, primary pollutant, effects human respiration and plant growth, major reduction in emissions through cap and trade, respiratory irritant, can form acid rain
39
how does sulfur dioxide form a secondary pollutant?
SO2 reacts with atmospheric oxygen to form SO3, which in turn forms droplets (haze & clouds) along with sulfuric acid; removed from atmosphere as wet deposition aka acid rain
40
where is acid rain a problem?
downwind of appalachian mts, westerlies, from CA to NY, florida
41
where are the biggest sources of SO2?
where coal-fired electricity plants are
42
characteristics of NOx
NO, NO2; used in fertilizer, CAFOs, gasoline, lightning; generated during FF combustion, more of a problem for coal than oil than for natural gas, first produced as NO (harmless), oxidizes to NO2; NO is highly reactive --> can produce more secondary pollutants, cause pulmonary problems
43
what happens to nitrogen dioxide in the presence of hv?
dissociated to nitric oxide and an oxygen radical (highly reactive); the O radical in turn can react with oxygen to form ozone
44
characteristics of hydrocarbons
not all bad, some carcinogens; vocs are a subset, can arise from incomplete combustion or industrial processes, emitted by motor vehicles, also common in nature; geosmin, turpine; most aromatics and scents, important for plant-plant & plant-animal communication, some primary pollutants, can contribute to poor indoor air quality
45
what does volatile mean?
low point of evaporation
46
which hydrocarbons are harmful on their own?
benzene and formaldehyde
47
what happens when VOCs combine with NOx?
play role in photochemical smog, producing more ozone, particulates, and other secondary pollutants
48
what are concentrations of pollution shaped by?
emissions, the volume or air that they're being emitted into, and their reaction & deposition removal processes from the air
emission sources --> atmospheric concentration --> reactions/deposition
49
what is vertical mixing layer?
refers to the altitude or "ceiling" to which pollutants are able to rise
50
what is horizontal movement?
refers to the distance pollutants are carried away from their source by the wind
51
what do diurnal changes in the mixing layer depend on?
solar radiation, albedo, clouds, seasons
52
what is advection?
horizontal movements** driven by pressure gradients (winds)**; moves pollution horizontally but not necessarily away from ppl
53
what is convection?
turbulent, vertical exchange of air; more convection means a larger (higher) mixing layer, is limited by stability of troposphere
54
when is the atmosphere unstable?
when the upper air is cooler than the ALR; an adiabatically rising air parcel near the ground is warmer than the env, causing it to rise
55
when is the atmosphere unstable?
when the upper air is cooler than ALR; an adiabatically rising air parcel near the ground is cooler than the environment, causing it to sink
56
radiation inversion
if temp rises with altitude, adiabatic air parcels wouldn't rise; occur on warm clear nights when ground cools, can occur during day and trap pollutants underneath; LW radiation leaving the surface at night is absorbed by the troposphere, air very close to the ground is cooled by conduction with the cool ground (fog along ground = moisture trapped vertically)
57
what is a subsidence inversion?
occur as a large air mass sinks, causing it to heat up relative to the air underneath; 30 deg south is where most sinking of air occurs
58
what is mixing depth?
inversions cause downward mixing, unstable atmospheres allow upward mixing, stable atmospheres cause exahust to move downwind
59
what is fanning?
stable atmospheres cause exhaust to move downwind without much motion up or down only spreading out horizontally
60
what is looping?
unstable atmospheres allow upward mixing in waving pattern that indicates atmospheric convection is occurring (when the smoke moves up and down); good for us, carries pollution away
61
what is fumigation?
when inversions cause some downward mixing; bad cuz it keeps pollutants on our level
62
characteristics of the NAAQS
atmospheric concentration of pollutants have declined, established nationwide standards for max allowed concentration, forces firms to pay cost of compliance (externality) rather than ppl paying health cost of pollution, all states subject to same standards
63
what are the primary standards acc to the NAAQS?
protect public health, including sensitive populations such as children and the elderly and asthmatics
64
what are secondary standards acc to the NAAQS?
protect public welfare including visibility, damage to crops, vegetation, animals, property
65
how did the NAAQs internalize externalities?
established diff zones:
- class I (national parks) no increases allowed
- class II (most of US) increases allowed, but not up to the NAAQS
- class III where increases up to the NAAQS were permitted
66
what is a catalytic converter and how does it work?
exhaust emission control device that operates on exhaust to oxidize hydrocarbons and carbon monoxide to CO2 and reduce nitrogen oxides to N2
67
what factors determine atmospheric concentrations of primary pollutants?
mixing layer height (volume, higher mixing layer height more dispersal), emissions, advection, deposition, precipitation, gravity, wind, ways of flushing pollutants out of atmosphere, sink process
68
what affects the depth of the mixing layer?
convection
69
what determines ozone depletion?
CFCs
70
what affects secondary pollutants in the atmosphere?
ultraviolet radiation
71
where does coal originate vs oil?
coal - land vegetation
oil - aquatic organisms
72
what is the most common fuel in the US?
natural gas
73
what are considered renewable forms of energy?
biomass, biofuels, wind, solar, hydropower, biomass, geothermal
74
what country has the highest energy consumption?
china; US has highest per capita energy consumption by region
75
difference between service economy and industrial economy
industrial burns more FF
76
what are the conditions for the formation of FF?
lots of organic material available in small area that was cut off from aerobic decay
77
formation of FF in swamps
submerged organic material had little oxygen and accumulated in layers and trapped sediment as sea levels fluctuated = coal
78
FF formation in estuaries
dense systems of phytoplankton and zooplankton died and were quickly buried by sediment transported from river systems = oil and gas
79
what are concerns with coal?
dirtiest for local air pollution, contributes to acid rain from SO2, carbon monoxide, leads to creation of secondary pollutants (H2SO4, combine w NOx, VOCs --> aerosols), most carbon intensive, mines contain radioactive material and mercury, land clearing from surface mining, acidic mine drainage can erode nearby landscapes (soil and bedrock)
80
primary production/recovery of gas/oil
oil and gas flow up into a well from the internal pressure of the reservoir underground
81
secondary production/recovery or waterflooding
oil and gas drillers inject water into the reservoir, displacing the oil up into the well
82
enhanced recovery/production
oil and gas recovery from lower permeability formations
83
thermal injection
reduces oil viscosity
84
chemical injection
increases viscosity of flooding water
85
extraction efficiency
percentage of total oil that gets extracted in production/recovery; depends on how permeable the rock is, how viscous oil is, what enhanced techniques were used
86
oil shale
shales are poorly permeable, holds substantial amts of oil and combustible gas between grains preventing reservoir from occurring, recovered by fracking, contaminates water
87
fracking
process in which fractures in rocks below earths surface are opened and widened by injecting chemicals and liquids at high pressure
87
tar/oil sand
sand mixed with viscous bitumen, requires lots of processing and dilution to turn into useful fuel product
88
oil/gas exploration concerns
disturbing animal behavior, lots of water used in exploration and production, water takes on pollutants, spills, GHG emissions and local air pollutants
89
what are non conventional FF deposits?
tar/oil sands, shale/gas oil, methane hydrates
90
shale oil/gas
rocks in which very fine pockets of crude oil liquid and gaseous bubbles form; poorly permeable, holds gas between grains, preventing conventional reservoir from forming; leakage of contaminated water into ground water from flowback pipes, potential for methane to escape into atmosphere
91
what is the processing process of oil?
shipped to refineries where they're distilled to separate hydrocarbons by weight and boiling temperature; lighter hydrocarbons have lower boiling points and will stay vaporized much higher in the column
92
where is oil most used?
to fuel vehicles: gasoline, diesel, asphalt
93
where is natural gas most used?
spread across industrial, residential, commercial, and electricity production
94
what is a natural source of particulate matter?
volcanos; ash = incompletely burned carbon
95
characteristics of lead
particulate, toxic metal, released through gas burned in cars, old paints, treated gasoline, causes brain damage, affects nervous system
96
how do we go from emitting positive GHG to negative?
carbon capture (storage in trees, aforestation, forest regulation) geoengineering, CO2 from biomass can go underground (geological storage), make building materials, growing kelp and sinking it into ocean, using ocean as sink; capturing CO2 at source BECS burning emitting capturing sequestration
97
what are the 2 forms of intermittent energy?
solar & wind
98
what sources of firm energy?
electric storage, hydropower, biofuels, geothermal, tides, waves
99
what do photovoltaic cells (solar panels) do?
take light energy or electromagnetic radiation --> electric energy
100
what are the layers of a PV cell and how does it work?
N, P, and depletion zone in between; a photon with visible wavelength can dislodge an electron from the middle depletion zone layer into the top N layer, then wants to find its way back to P layer which is able to accept electrons; if layers are connected with a wire, electrons can move through it
101
what is the correlation between sunlight and PV cells?
less sunlight available (higher latitude, more clouds) the wider your array needs to be to capture a certain amt of solar energy
102
what are the area requirements of a PV cell?
wide surface area, a big, continuous, ground-level setup that is infeasible where land costs are high, but lots of co-location potential on rooftops & other land uses
103
describe the intermittency of solar energy
peak electricity usage hours (evening) can differ from peak sunlight (noon), seasonal flux: every day there are fewer hours of sunlight, lower zenith angle at midday, traveling through more atmosphere (when sun is at angle, rays are coming in at sloped angle), cloudier days, snow cover was a past concern
104
characteristics of wind energy
type of solar energy, temperature (and thus pressure) gradients drive winds towards the poles
105
where does the coriolis force drive winds?
east to west
106
wind energy land requirements
large area because power density is less than solar, but doesn't exclude use of land for other things, can be farmed around
107
how do turbines work?
any turbine generates electricity by rotating a copper wire coil in a magnetic field (or rotating a magnet around a copper wire coil), wind turbines use the air to blow fan blades that are attached to magnetic core, which rotates around copper coil; kinetic energy --> electric energy
108
how do renewables complicate energy?
intermittency; ex. during windless nights, conventional power plants need to be quickly ramped up that has monetary and emission costs
109
what are ways to store energy?
turn intermittent energy into firm energy: batteries, pumped water storage (power plant in conjunction with a dam), raising and lowering bricks, green hydrogen (hydrogen produced by splitting water through electrolysis)
110
characteristics of hydropower
mechanical energy for flood control, irrigation, used as firm energy source in colonial US, very low carbon electricity generation
111
negatives of dams
equity concerns, not carbon neutral, decomposition of organic material, limited oxygen flow --> decomposition generates methane, emissions lower than coal/gas but not wind or solar, displacement of ppl, reservoirs food rivers upstream & deplete rivers downstream, habitat destruction
112
what are concerns with biofuels?
land use change, deforestation, displaces native forests and prairies, PM, carbon from burning forests, methane production, NOx (fertilizer)
113
what is direct coupling?
products like edible corn or soybeans or sugarcane can be used for both food or fuel, the price of food is commonly linked directly to energy prices
114
what is indirect coupling?
whether biofuel is an edible product or not, high prices for biofuels can crowd out use of land for food production
115
what is an isotope?
same elements with diff #s of neutrons (same # of protons)
116
neutron
no charge subatomic particles
117
electron
negatively charged subatomic particles
118
proton
positively charged subatomic particles
119
what is binding energy?
energy contained in nuclear bonds contained between nucleus particles
120
what is mass defect?
the difference between the mass of individual particles in the nucleus summed up and the mass of the actual nucleus equals the net mass in their bonds;
mass of neutrons + mass of protons - mass of nucleus squared ---> tells how much mass an atom loses when its fissioned or fused
121
what is radioactivity?
property exhibited by some types of matter emitting some energy and subatomic particles (mass) spontaneously
122
what does fissile mean?
able to undergo fission after absorption of a slow-moving neutron
123
what does fertile mean in nuclear physics?
cannot undergo fission; can transform to fissile by absorbing neutrons
124
what is ionizing radiation?
any type of radiation that had enough energy to discharge an electron, breaking molecular bonds of an atom, dangerous for humans & env
125
nuclear binding energy
higher binding energy means more stable nucleus, very light nuclei can be fused together forming more stable nuclei; much heavier nuclei like uranium or plutonium can be fissioned apart, forming more stable nuclei --> energy lost, lower energy state supplies more stability
126
radioisotopes
molecules that naturally decay, emitting particles (including neutrons, electrons, protons) at specific rates (semi-random)
127
alpha-decay
neutron emissions; enough alpha-emitting radioisotopes together in one place will set off a rapid chain reaction
128
types of uranium
U235 is fissile, can participate in sustained fission reaction;
U238 is more common, not fissile but fertile; can absorb neutrons to become plutonium, present in all nuclear fuel
129
plutonium (P239)
fissile, nearly non-existent in nature, human made form can make up nuclear fuel
130
process of U238 becoming P239
by absorbing neutrons; **conditions have to be just right, a neutron ejected from a radioactive nucleus has to be likely to hit another fissile nucleus and hit at the right speed**
131
what are moderators?
substances that will slow down and absorb energy from **neutrons** without absorbing too many neutrons themselves (water and graphite)
132
what does reaction control look like in a nuclear power plant?
control rods control the speed of a nuclear reaction by absorbing lots of neutrons without themselves fissioning or "poisoning" of coolant or moderator with neutron absorbing materials
133
how does a pressurized water reactor work
1. coolant/moderator cycle constrains the reactor
2. steam cycle generates the electricity
3. cooling/condenser cycle condenses the steam and dissipates the heat to the greater env (cool water source)
134
describe the fuel usage cycle
| nuclear
concentrate u235 so mass is fissile enough, natural uranium is mined as an ore, has to be processed in order to be useful, depending on country could be recycled; ends up as long-term radioactive liability that must be stored carefully
135
nuclear fuel production process
raw ore is milled and concentrated to produce "yellowcake", which is converted and vaporized into uf6 which ahs a high vapor pressure (becomes a gas at a relatively low temp); gassified 235uf6 moves more quickly in the air than 238uf6; uf6 converted to uo2 powder, uo2 powder processed into ceramic pellets, ceramic pellets sealed into fuel rods
136
how can a person hold a fissile pellet without it melting?
they only undergo reactions when in proximity with other pellets; they don't produce heat until with other pellets
137
what is left in spent fuel after it's used?
significant fissile U235, fertile U238, fissile PU239
138
reprocessing nuclear fuel material
can be reprocessed (by separating uranium/plutonium from waste products by chopping fuel rods & dissolving them in acid) to return it to concentrations for which the reactor was designed; concerns abt plutonium capture by terrorists; banned in US but allowed in UK, india, japan, russia, france
139
where does fuel slated for long-term disposal go?
held in either pools or dry casks for some months in order to cool down from fission reaction
140
how does long term storage of nuclear waste work?
depending on radioactivity, waste from nuclear processes may need to be stored for years, centuries or millennia; for most of the more harmful wastes, geologic disposal
141
risks of nuclear reactions
- heat arises from both chain reaction and decay heat, must always be able to pump heat away or risk overheating --> can lead to explosive reaction of fuel rod, overheated rods react w water --> core meltdown
142
spent fuel containment failure
spent fuel must be processed via breeder reactor or stored to isolate fuel for long time
143
risks of ore mining
mining generates ore tailing but also removes radioactive radon from env; compared to coal mining, net gain
144
three mile island
scale 5;** cleaning of filters** led to water in an instrument air line (which affected instrument signals), led to **feedwater pumps shutting down, triggering emergency shutdown;** **auxiliary pumps** meant to turn on, but were **offline** for maintenance; more decay heat produced --> **overheating, pressure release valve opened to reduce pressure, stayed open --> loss coolant accident**; no direct deaths, debate abt cancer, no clear env impact, triggered partial slowdown to nuclear plant growth
145
chernobyl
scale 7; backup generators were slow, **experiment **was planned to see if steam turbine water could help power emergency systems in the first minute of a shut-down. problems during experiement led engineers **to disable a # of safety systems & manually remove control rods;** **coolant system had unstable design,** too much steam formed, nuclear reaction in interior rapidly decreased; **emergency shutdown initiated,** **dumping all control rods which had graphite tips,** leading initially to a large spike in power before control rods full lowered; **coolant water became superheated and vaporized, causing explosion**; reactor was not contained, graphite moderator flammable, roofing material flammable
146
impacts of chernobyl
nearby forests dried up and died, horses died of thyroid problems, agricultural restrictions immediately after, 28 acute deaths, 4000 cancer deaths estimated
147
fukushima
scale 9; 6 units, boiling water reactor; earthquake triggered an automatic shutdown, cut power; diesel generators were triggered to keep coolant flowing, tsunami knocked out seawall flooding generators, overheating led to hydrogen generation and explosions allowing leakage, meltdown followed but extent is unknown
148
effects of fukushima
no deaths, low est cancer effects, life expectancy impact more by relocation stress; safe ocean radiation levels
149
advances in nuclear safety
generation III plants shut down with
1. no moving working fluid
2. no moving mechanical part
3. no signal inputs of intelligence
4. no external power input or forces
150
what is the default state of a nuclear power plant not working?
control rods down, no heat generated
151
generation IV plants
feature passive safety of gen III, new advances in efficiency, smaller nuclear cores, fuel of uranium metal allows less able to create runaway reactions at extreme temps; most recent "advanced small modular reactors" SMRs
152
economics of nuclear power
lower relatively fuel costs but higher capital costs in making sure plant is safe for startup; long lead time to startup
153
what is nuclear fusion and why is it not common?
collision of atoms produces an energy yield possibly much higher than fission & w/ less radioactive byproducts; need heavy hydrogen that have multiple additional neutrons
154
what are the isotopes of hydrogen needed for nuclear fusion?
deuterium, tritium; colliding them produces a sun on earth: high temp plasma, high ion density, sufficient ion confinement time
155
what is the tokomak plasma confinement device?
a toroid shaped chamber with inner magnetic coil designed to contain a plasma magnetically, inner plasma reaches 100 mil degrees C
156
what are major causes of sulfur pollution & what reduced it?
heating oil (for buildings); citywide initiative to switch to low sulfur heating oil; no 6 oil banned, no 4 fuel phased out
157
what sector primarily uses natural gas & what for?
residental/commercial for heating and cooling, gas stoves, hot water heater
158
what percentage of renewable power is hydropower?
20%
159
explain FF creation
1. area with high NPP --> lots of organic decayed matter gets buried and cut off from aerobic decay (diagensis)
2. further burial resulting in higher pressure and temperature (catagensis)
160
what is nuclear power primarily used for?
electric power generation
161
what is the most used FF?
oil
162
what factors constrain solar panel use?
intermittency (time of day), installation costs, shading by other buildings, latitude/geography
163
what are the major sources of NO2
highways (car exhaust) & densely populated areas
164
how does tropospheric ozone form and what are its consequences?
respiratory irritant & bad for env, gets pushed downwin, UV bounces oxygen off of NO2 leaving free oxygen, which combines with elemental oxygen O2, creates O3 / NO2 molecule splits apart in presence of UV light, free oxygen is unstable and latches onto O2 --> ozone
165
what is the relationship between PM, trees, and surface area?
trees remove PM & maximize surface area --> can absorb more PM; high surface area to volume ration --> more PM can deposit; PM can cause respiratory illness
166
environmental racism
any policy, practice or directive that differentially affects or disadvantages (whether intended or unintended) individuals, groups, or communities based on race or color
167
environmental justice
the principle that all ppl and communities are entitled to equal protection of env and public health laws and regulations; fair treatment and meaningful involvement of all ppl regardless of race, color, national origin, or income with respect to the development, implementation and enforcement of environmental laws, regulations, and policies
168
goals of env justice
1. the same degree of protection from environmental and health hazards
2. equal access to the decision making process to have a healthy env to live, learn, and work
(not solution based or define meaningful involvement, addresses present/future not past, gender & ability not included)
169
what happened in warren county?
they tried to dump pcv contaminated soil
170
explain uneven penalties in environmental justice
fines for env "crimes" are higher in white communities than in black communities
171
4 components of global injustice
1. env justice is primarily about waste
2. waste is inextricable from economic growth
3. growth in inextricable from capitalism
4. where we place waste is inextricable from cultural ideas of the value of the lives of others
172
UN definition of a sustainable society
a sustainable society meets the needs of the present generation without compromising the ability of future generations to meet their own needs (doesn't account for equity, incentives, reparations)
173
4 principles of sustainability
1. dont use natural resources or produce waste faster than they are regenerated or assimilated by the env
2. connections between different interrelated parts of the env can cause decisions to succeed or fail
3. principles 1 & 2 must be guided by fairness among nations, creeds, sects, races, genders, and current and future generations
4. social incentives must reward those who act in a sustainable way and punish those who act in a non-sustainable manner
174
decline in birth rate will come from:
moving from agrarian to urban setting, higher incomes, education and access to family planning
175
inc in birth rate in higher income countries from:
better gender equality & better medical care leading to longer lives
176
population momentum
we know how many babies there are now that will be entering reproductive age later
177
kaya's equation
CO2 = population x GDP/capita x energy/GDP x CO2/energy
178
efficiency vs scale of economies
scale - population, affluence, total economic activities
efficiency - better tech, energy efficiency, renewable energy resources, agricultural --> industrial --> service
179
kuznet's curve
idea that as countries develop, they go from more polluting to less polluting
180
what is geothermal energy?
heat from radioactive decay deep within earth
181
what are the 3 techniques of converting geothermal energy into useful energy?
1. geothermal electricity generation (flash steam power plants)
2. direct use (using the heat in the water directly without converting it first to electricity)
3. heat pump (pump that uses earth as heat source & sink)
182
how does ocean thermal energy work?
the ocean is the largest solar energy collector; the sun heats surface waters creating a temp gradient w/deep water, then converts this into electricity; very expensive
183
how does tidal energy work?
"barrage" technology that **dams a tidally affected estuary** or inlet, allowing the tidal flow to **build up on the ocean side of the dam,** generating electricity **during high tide**; after max high tide gate valves are closed and water is impounded, awaiting low tide when its released back through the dam where it generates electricity
184
what are drawbacks of tidal energy?
small amt of energy generated, out of sync w/ peak electricity, largely in estuaries/coastal ecosystems --> affects env services
185
how does wave energy work?
form of potential energy due to elevation of wave above the still-water level, & kinetic energy due to orbital motion of component particles; matter of translating into mechanical/electrical energy, difficult to develop in cost-effective manner
186
how does hydropower work?
produced by force of falling water; uses dam on river to store water in reservoir; water accumulates potential energy behind the dam, transforms into kinetic energy when water rushes down a tunnel and strikes blade of a turbine, the rotation spins electromagnets that generate current in coils of wire
187
what is a pumped storage plant?
power is sent from power grid into the electric generators at a hydro facility.** generators spin the turbines to pump water from a river or lower reservoir to an upper reservoir creating storage of potential energy.** when needed, **water is released from upper reservoir back down into the river/lower reservoir, turning turbines & activating generators to produce electricity**
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hydrogen power
hydrogen must be manufactured from other materials (methane, water), has low energy density; produced by steam reforming of natural gas, splitting water into hydrogen & oxygen (electrolysis)
189
what are the primary methods of hydrogen storage?
compressed gas, liquified hydrogen, metal hydride, carbon-based systems; compressing the gas allows a greater amount of energy to be contained in a given volume
190
drawbacks to hydrogen as an energy source
not readily available as energy, costly & requires large inputs of energy, high transmission costs, low energy density
191
hydrogen fuel cells
H can be used in stationary applications to generate electricity and provide mobile power; fuel cells generate electricity through an **electrochemical process **in which the energy stored in a fuel is converted directly into DC; **it converts hydrogen fuel and oxygen from atmosphere into electricity; fuel is stored externally**
192
primary coolant vs secondary coolant
primary - used to remove heat generated by fission & to maintain temp of fuel
secondary - flows around outside of tubes & picks up heat from primary coolant
193
what are 3 components of decommissioning a nuclear power plant?
decontamination, safe storage, entombment
194
what is geological disposal?
packaging wastes inside long-lived containers that are sealed and placed deep underground
195
what are some nuclear diversion concerns?
1. terrorists stealing fissile/radioactive materials
2. countries obtaining nuclear weapons through civilian nuclear facilities
3. radioactivity released through attacks on reactors
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why are market-mechanisms the better option for sustainable policy?
helps establish continuous progress beyond set goal, otherwise there is no incentive for further reductions
197
what is the relationship between policies that focus on efficiency and energy?
seek to diminish the amt of energy used to produce an inflation correct dollars worth of GDP (energy/gdp)
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total energy use equation
energy use = energy use/GDP x GDP
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problem with solely focusing on economic efficiency
there may be ecological limits on scale of economic activity
200
downsides of subsidies
bad from economic perspective, can increase env degradation in long run by increasing scale of industry (from reducing average costs of producing a good which increases profitability of production, attracts new firms, increases output
201
why is wind energy a form of solar energy?
the uneven heating of the atmosphere by the sun, irregularities of the earths surface, and earths rotation cause it
