Science Section 4 Flashcards
What is an organism that is used to study air pollution because it holds pollutants in its tissues?
lichens!
Who was the researcher who led a group environmental scientists to study pollution using lichens to monitor pollution from the copper smelter town of Karabash (in Russia)?
O. William Purvis (ik cool name right)
In what layer of the atmosphere does air pollution refer to the pollution of?
the troposphere
What are the six major air pollutants (according to the resource guide)?
- these are considered to be the most widely harmful to human health
- sulfur dioxides
- nitrogen oxides
- carbon monoxide
- lead
- particulate matter
- ground-level ozone
As a part of what act, did scientists identify the six major air pollutants?
the Clean Air Act (CAA)
Where does sulfur dioxide come from?
naturally: volcanic eruptions
humans: burning fossil fuels
Why is sulfur dioxide particularly harmful to mammals?
harmful to mammalian respiratory systems because it can reduce lung function
Why might sulfur dioxide be harmful when its released into the atmosphere (environmental-wise)?
it can undergo a chemical reaction in the atm. and form sulfuric acid = acid rain!!
What element makes up the majority of the atmosphere?
nitrogen gas (N2)
What percent of the atmosphere is nitrogen?
78%
What process is nitrogen oxide a product of in the atmosphere?
combustion leads to formation of a wide variety of nitrogen oxides
Why is nitrogen oxide harmful to ecosystems?
Like SO2, NOx (x meaning it can have a number of oxygen molecules) can undergo chemical reactions in the atm. to form nitric acid
How is carbon monoxide formed?
natural: during INCOMPLETE combustion of most organic matter
human: major part of automobile emissions
Why is carbon monoxide harmful to living organisms?
CO binds with the hemoglobin (responsible for transporting oxygen through blood) and doesn’t allow oxygen transport, thus causing dizziness, headaches, confusion, loss of consciousness, and even death
Where does lead (Pb) come from?
natural: naturally occurring element that is a part of Earth’s crust
human: used as additive in gasoline, emitted into atm. when burned
What decade did sale of leaded gasoline end in the US?
1970s
What year did sale of leaded gasoline end globally?
2021
Why is lead harmful to living organisms?
impacts animal blood production, producing anemia
- adverse neurological impacts, particularly on young children
What does particulate matter refer to?
solid or liquid particles suspended in the air
Where does particulate matter come from?
most combustion products, commonly known as a class of pollutants resulting from “dirty burning”
Particulates that range in diameter between 10 microns - 2.5 microns is classified as what?
coarse
Particulates that are SMALLER than 2.5 microns are classified as what?
fine
Between “course” and “fine” particulates, which group poses a greater health risk?
fine particulates
- they can deposit deeper into lungs than course particulates
Why might particulate matter be bad for the environment (aside from posing a health risk to living organisms)?
they can block sunlight and reduce photosynthesis
Ground level ozone is also known as what?
smog. photochemical air pollutants (class of air pollutants formed from the sun reacting with oxides, like nitrogen and sulfur oxides)
What is photochemical smog?
term referring to the haze that appears over cities
What is the molecular composition of ozone?
three oxygen molecules
In what layer of the atmosphere does the ozone layer form?
stratosphere
What is the purpose of ozone in the STRATOSPHERE?
absorbs ultraviolet light, removes harmful radiation
What happens if ozone is in the TROPOSPHERE?
it becomes harmful to plants and animals because it causes chemical burns on organic material
What does VOCs stand for?
volatile organic compounds
Where do VOCs come from?
Chemicals with a scent that evaporate easily. Can be human-produced like gasoline, paints, pharmaceuticals, and refrigerants or natural like eucalyptus. Part of the reaction that creates photochemical smog
human produced VOC’s are bad bc it results in more smog, which has ozone
In manufacturing which of the following are VOCs NOT produced?: paints, pharmaceuticals, peanut butter, refrigerants
peanut butter
How are primary pollutants different from secondary pollutants?
primary pollutants remain in the form that they were emitted
How are secondary pollutants formed?
they are the result of chemical reactions involving primary pollutants
Is smog considered a primary or secondary pollutant?
secondary
Would CO (carbon monoxide) be considered a primary or secondary pollutant?
primary
How are VOCs naturally released?
living plants release VOCs (causing the smell of conifer trees and citrus fruits)
What are some natural sources of pollutants?
volcanoes, forest fires, grassland fires, living plants, and dead plants, even the intestinal tracts of domestic livestock contribute to air pollution via methane emissions
What is atmospheric (thermal) inversion?
when a layer of warm air blankets a layer of cooler air below it and trap pollutants that were released at ground level in the troposphere, and cause a severe pollution event
NORMAL AIR (in order from highest to lowest) = cool air, cool air, warm air
THERMAL INVERSION AIR (in order from highest to lowest) = cool air, warm air, cool air
What is the most common unit used for the comparison of energy sources?
Btu, British thermal unit!!
What is 1 Btu the equivalent of?
the quantity of heat required to raise the temperature of 1lb of liquid water by 1 degree Fahrenheit at the temperature water has its greatest density (approx. 39 degrees F)
In 2021, about how many quad Btu of energy did the US use?
97 quadrillion Btu of energy
In 2021, about how many Btu of energy did China consume?
165.168 quad Btu of energy
What is the difference between nonrenewable and renewable fuels?
nonrenewables go like VROOOMM
and renewables go like hhhhhhh *spaceship noises
no but actually, nonrewables have a FINITE amount present on Earth (in the context of thousands of years) whereas renewables are those that are replenished by a process such as shining of the sun or blowing of the wind
Why is the use of fossil fuels not sustainable?
future generations will not have access to these fuels if we completely use them up over the next few decades
High-tech electronic industries in California and the Pacific Northwest use electricity generated from what?
renewable energy sources!
Northern parts of the US use more of what two fuels during the winter months to generate heat and electricity?
oil and natural gas
The central US use what fuel source for their steel manufacturing?
coal (boooo)
The Northeastern US uses more of what fuel sources for electricity generation (there’s 3)?
nuclear, natural gas, and hydropower
Electricity generation is the Midwest and Southwest of the US is dependent upon what primary fuel source?
coal
Coal combustion is _____common in areas of ______ population density because coal creates the most air pollution.
less; high
What is energy efficiency?
measure of ow effective we are at getting useable work from a given input of energy (the amount of energy or work output, in desired form / total energy output)
What are the two main factors that can make energy INefficient?
- heat loss, no energy source is ever 100% efficient, although some are close
- the number of steps in the system, the more steps, the more opportunities for energy loss
What does the United Nations Development Program World Energy Assessment estimate is the global energy efficiency (in percentage)?
about 37%
What are some ways that transportation can be made more energy efficient?
- fuel efficiency of the mode of transport (AKA miles per gallon)
- how much energy contained in the fuel source
- how many people are being transported at the same time
- the amount of “work” demanded from the mode of transport
If an energy source has FEWER energy conversions to get to the desired form of energy, is it more or less efficient?
MORE efficient because there are less opportunities for energy to be lost as heat
What is an energy source that is commonly used throughout the developing world to generate heat?
animal dung
Is electricity classified as an energy source or a fuel?
ENERGY SOURCE, it is not a fuel because it is no the original source of energy, it must be generated by fuels
Describe the general steps in generating electricity.
- Fuel extracted
- Fuel burned or heated to generate heat
- Heat used to boil water
- Boiling water generates steam
- Steam used to turn a turbine
- Spinning turbine powers a generator
- Generator generates electricity
What is the power grid?
large electricity delivery system, grid loosely connecting power plants to provide electricity to homes in a given area
As of 2022, what percentage of US electricity is generated by natural gas?
40%
What does the resource guide say that coal was originally formed from 160-400 million years ago?
tropical plants growing in swamps and marshes
How is coal formed?
- organic matter dies, and decomposes
- decomposed matter is buried by sediments over decades
- continued burial, and as this matter travels deeper into Earth’s lithosphere it is exposed to high pressure and temperatures
- intense conditions compact the matter into a dense, and energy-rich carbon material
= coal, petroleum, and fossil fuels in general
What is the order of coal classification from least to greatest energy content (and therefore time and pressure needed for formation)?
- peat
- lignite
- bituminous coal
- anthracite
What is the most concentrated, greatest energy form of coal?
anthracite
What form of coal has the least amount of energy?
peat
What are the two main methods of coal mining?
- deep shaft (underground, subsurface, digging tunnels to dislodge goal)
- surface mining (digging into a pit, removing a mountain top, strip mining, etc.)
What are some environmental impacts of mining?
- emissions of harmful air pollutants
- mining degrades water quality
- can cause acid mine drainage (precipitation carries mine pollutants with it to nearby waterways and pollutes them, creating dead zones, or excessively acidic water)
What is elements is petroleum a mix of (three elements)
hydrocarbons, water, and usually sulfur
What living organism is petroleum said to be formed from 65-250 million years ago?
ocean-dwelling plankton
How is petroleum extracted?
wells, drilled on land, and under water, pumped from the ground
When the gas is separated from petroleum it is called what?
crude oil
Crude oil (from petroleum) is refined into what?
gasoline, diesel fuel, and kerosene
How does petroleum compare to coal as a fuel source in terms of its environmental impact?
Petroleum is a lot more “clean-burning” than coal, but its remains a significant source of water pollution
80-95% of natural gas is what compound?
methane (CH4)
Where does natural gas naturally occur?
lies above oil in rock strata
What are the benefits of using natural gas as a fuel source?
- contains fewer impurities, giving rise to virtually no SO2 and particulates during combustion (burning)
- only produces 60% as much CO2 as coal for the same amount of energy produced = lower GHG contributor
most natural gas is methane, which is released from landfills. Methane traps more solar energy than carbon dioxide, so releasing it is a big no-no, and it’s hard to store. That’s why it can be especially good to burn natural gas from landfills cuz it’d be a worse pollutant otherwise and it’ll be there anyway unless you burn it, then just CO2 is released
What are the drawbacks of using natural gas as a fuel source?
- releases GHGs when its extracted
- MAJOR cause of CH4 pollution when leaks occur (remember methane is SIGNIFICANTLY more potent as a GHG compared to CO2, so it traps a lot more heat in lower concentrations in the atm.)
this is specifically about using nat. gas from underground that you get through fracking. It’s not much better than other fossil fuels. Natural gas from landfills doesn’t have most of these risks though because it is already a by-product of the landfill and the burning gives energy and lowers the amount of GHG equivalent released. obviously still worse than renewables though
What does hydraulic fracturing involve?
injecting high-pressure streams of water, sand, and chemicals into bedrock to create fractures in the rock formation, basically mining with water pressure and chemicals
you do this to form cracks so that nat. gas can escape the rock
What are some benefits of hydraulic fracturing?
- allows previously unreachable reservoirs of oil and natural gas to be tapped
- fracking = major reason why natural gas has overtaken coal as second most used energy source in the US
What are some drawbacks of hydraulic fracturing?
- fluid that is used to “frack” contains chemicals that are hazardous to human health
- large scale fracking operations use tremendous amount of water
- dramatically lowers key aquifers
What color is uranium??? (when its oxidized)?
YELLLOW
Are uranium and nuclear fuel the same thing??
NO!: as much as 2,000 lbs of uranium must be mined to produce just 7lbs of uranium oxide for nuclear fuel (but this 7 lbs is mighty concentrated with energy)
has to be refined to be fuel!
Describe the steps to convert uranium rock to energy.
uranium is extracted from rock and concentrated –> uranium is then enriched to remove impurities –> it is processed into pellets —> these pellets are put into hollow fuel rods –> the pellets undergo rapid radioactive decay (splitting into more atoms) and releasing heat, then begins the rest of the typical electricity generation steps
What is a fission reaction?
when an atom splits and releases heat energy
1lb of enriched uranium (smaller than a baseball) has the energy content of how many gallons of gasoline?
1 MILLION GALLONS!!
What are some benefits of using nuclear power?
- it is considered “clean” because power plants do not produce any air pollution when they are operating
- emits less CO2 per kilowatt-hour of electricity generated compared to coal
What are some consequences of using nuclear power?
- fossil fuels are used during other parts of electricity generation using nuclear fuel, i.e; transportation, when plant is constructed, when fuel rods are transported to the storage location
- the waste is dangerous and requires lots of effort to store and manage
- the water used in cooling is warmed, so it causes thermal pollution in neary waterways it is released into
Which nuclear accident occurred on March 28, 1979?
Three Mile Island, Pennsylvania nuclear accident
Which nuclear accident occurred on April 26, 1986?
Chernobyl, Ukraine nuclear accident
Which nuclear accident occurred in March 2011?
Fukushima power plant accident in Honshu, Japan
What happened in the Three Mile Island, PA nuclear accident?
human error caused a cooling valve to be closed, loss of coolant around nuclear core, core overheated, small amount of radiation released
What happened in the Chernobyl nuclear accident?
plant operators disconnected emergency cooling systems and removed control rods, nuclear reactions were out of control, the plant overheated, plant exploded
- due to a lot of construction materials for the plant being made out of lead, fires burned more intensely!
What happened in the Fukushima power plant nuclear accident?
major earthquake, resulted in a tsunami that flooded the reactors of the plant, caused radioactive leakage, est. it will take 40 years to finish decontamination work
What are the three forms/levels of radioactive waste?
- high-level waste from spent fuel rods
- low-level waste from contaminated maintenance materials
- the uranium-residue that is left over after uranium mining and enrichment
What is the MOST dangerous form of radioactive waste that requires the most careful handling?
spent fuel rods (nuclear fuel rods that don’t have enough fuel left to produce enough heat to generate electricity)
What are spent fuel rods?
nuclear fuel rods that don’t have enough fuel left to produce enough heat to generate electricity
Why are spent fuel rods still dangerous, even though they’re “spent”?
still contain highly radioactive fission fragments that will remain a threat to humans and organisms for tens of thousands of years
Currently, where are nuclear power plants required to store their spent fuel rods?
in the plant itself, in pools of water (at least 20ft deep)
- water acts as a shield from radiation
- rods then moved to onsite cement storage canisters called dry cask storage
What was significant about the site at Yucca Mountain, Nevada?
in 1978, the US Department of Energy began examining the site at Yucca Mountain, NV as a possible long-term repository for the country’s spent nuclear fuel and radioactive waste
- ultimately did not come together due to scientific uncertainty in geological stability
What are TWO MAIN ways to increase energy sustainability?
- using less energy through improving energy efficiency
- energy conservation
What is the difference between renewable energy and potentially renewable energy?
renewable energy sources are based on sources that cannot be depleted, as long as the Sun and Earth survive
- potentially renewable is only renewable if the source is managed properly, used in moderation/balance so that the source can replenish
Fossil fuels, hydrologic power, and wind power are examples of what type of solar energy?
indirect solar energy
What is the solar constant?
the amount of solar energy reaching the top of the Earth’s atm.
What is the solar potential?
the energy that is potentially available for use by people
About how many watts of solar energy arrive at Earth’s surface near the equator because the atm. reflects and absorbs a good portion of solar energy?
200 watts
Building a house out of material with greater thermal inertia, positioning the house so it absorbs the most energy, and using dark materials for the building are examples of harnessing what type of solar energy?
passive solar energy
What is passive solar energy?
collecting solar energy directly from the rays of the Sun without an immediate technology (like a pump or blower)
What is active solar energy?
systems that utilize energy from the Sun with assistance of fans, blowers, and pumps
= used for two primary applications: heating hot water and generating electricity
What kind (what element is used) of tubing is used in water heating active solar systems?
copper
Using what element/material do photovoltaic solar cells generate electrical currents?
silicon dioxide (generate current when exposed to sunlight)
Normally, how many photovoltaic cells are joined together in one solar panel?
24
What is a wind turbine?
device that converts the kinetic energy of wind to the potential energy of electricity
How many offshore wind farms are in the US?
2 (yea it’s kind of sad, but more are being planned)
About how many offshore wind farms are in operation in Northern Europe?
40, with over 2,000 total wind turbines
What are some benefits of using solar and wind energy?
- provide heat and/or electricity w/out - producing air or water pollution
- no fossil CO2 emissions
- provide energy to remote locations
- produce energy savings and offset pollution
- wind turbines compatible w/ other land uses
What are some drawbacks of using solar and wind energy?
if you said any of these you’re good:
- the sun doesn’t shine and the wind doesn’t blow all the time
- some of the energy produced when conditions are good will need to be stored
- storage requires large-scale battery production = difficult and expensive
energy is lost, even in battery storage
- batteries require heavy metals to be mined
- has an aesthetic disadvantage: people do not like living near turbines
- estimated 10,000 -40,000 birds die each year in collisions w/ windmills
What are the two factors that determine how much electricity is generated from hydropower?
- vertical distance fallen
- flow rate of the water
What are the TWO main types of hydroelectric generation?
- run-of-the-river
- water impoundment
What is a run-of-the-river hydroelectric generation system?
water is diverted from a river, passed through a narrow channel, and directed toward a turbine, returned to the river after
What are the main characteristics of a run-of-the-river system?
- mostly small scale
- not stored in a reservoir, dependent on natural flow
- limited usefulness during drier months
What are the benefits of using a run-of-the-river system?
- much less impact on aquatic plants and animals than water impoundment
- high and low flow periods continue, species swimming upstream not disrupted
What is a water impoundment hydroelectric generation system?
storing water in a reservoir behind a dam–flow of water is controlled, and allows for electricity generation on demand
What are some drawbacks of using a water impoundment system to generate electricity?
- water that was formerly free flowing is now stored, an area of land is flooded
- could mean loss of forest, rich bottom land ideal for agriculture, canyons, or wild river recreation
- ecological communities destroyed, people displaced
- Hydro dams create conditions for anaerobic bacteria to thrive in flooded vegetation, mobilizing mercury to be converted to methyl mercury, easily bioaccumulates in fish and ultimately humans
- large scale projects alter the ecology of the water and land areas
life cycles of organisms like salmon, trout, and clams depend on natural variations in water flow
cottonwood trees depend on sandbars created by natural flooding
What are the benefits of using a water impoundment hydroelectric system?
- produce large amounts of electricity , much more than any run-of-the-river station could produce
What is biomass?
is the potential energy contained in organic matter
List some examples of biomass that are burned to heat homes or water or to cook food, or produce electricity.
- plant remains
- wood, charcoal
- ethanol
- animal dung
Biomass products account for what percent of renewable energy consumed in the US?
~37%
Why does burning biomass not contribute to pollution like burning fossil fuels does?
biomass is modern carbon, whereas fossil fuels are fossil carbon
What is modern carbon?
the carbon was in the atm. until fairly recently (time span ranges from a few months to a few hundred years ago)
- once the biomass is removed, new growth replaces it and offsets the carbon released from removing it
- no large effect on global CO2 concentrations
What is fossil carbon?
carbon removed from the atm. MILLIONS of years ago
fossil carbon burned = net increase in global CO2 concentrations, that carbon cannot just be offset easily by new growth, that carbon was previously sequestered for millions of years
Is animal dung modern or fossil carbon?
modern
Is petroleum modern or fossil carbon?
fossil
What crop is ethanol derived from?
corn
How is ethanol made?
fermentation of corn and corn by-products
What is ethanol used for?
- mixed with gasoline to help oxygenate it and absorb moisture in gasoline to prevent freezing
- reduces the amount of gasoline used and replaces fossil carbon with modern carbon
What are some drawbacks to using ethanol?
growing corn and converting it to ethanol uses fossil fuels
- also takes up agricultural land
What is geothermal energy?
heat produced from the radioactive decay of elements deep in the Earth
What are the benefits of using geothermal energy?
- easily tapped and relatively inexpensive
- energy can be used directly to heat water
- can be used as primary energy source to produce electricity by creating steam to power turbines
- no greenhouse gases or other pollutants from fossil fuels
What are some drawbacks of using geothermal energy?
- can emit other localized, dangerous gases
- geographically limited to those areas that are geologically active
What country is known for its active volcanoes and gets 100% of its electricity from renewable resources?
Iceland
How is tidal energy produced?
from the natural rise and fall of tides
Why is tidal energy not common?
- difference between water level in high and low tide isn’t great enough to provide enough kinetic energy to generate sufficient electricity
- power stations must be build directly on coastline, which is ecologically disruptive to valuable estuary habitat
What is conservation?
a consumer-based approach that focuses on reducing energy use by changing users’ habits and actions. this approach is available to anyone, but it’s drawback is that it requires changing long-standing habits.
What would you be practicing if you take shorter showers, turn off lights and unplug when they’re not in use, or wear warmer clothes instead of turning on the thermostat?
CONSERVATION
Increasing energy efficiency means to do what?
use less energy to do the same work
What is peak demand?
the certain time of day, or certain time of the season when people are using more energy than normal
How can one reduce peak demand?
- conduct optional activities that demand electricity at non-peak times!!
- peak demand electricity is billed at a higher rate, businesses or consumers might choose to wait to run appliances until after peak demand period (8AM-8PM)
- purchasing Energy Star appliances to designate compliant appliances that do their job at a specified level of efficiency
What label should you look for on appliances to ensure energy is conserved and efficient?
Energy Star
What is the radioactive gas that results from breakdown of uranium?
radon
Why is radon dangerous to humans?
humans exposed to radon from seeping into homes or drinking water, underlying rock, soil, or groundwater at risk for lung cancer
What are the three steps in accounting for risks?
1) Risk Assessment: How much risk is there?
2) Risk Acceptance: How much risk is acceptable?
3) Risk Management: How can we manage the risk?
What is ecological risk assessment?
the risk to non-human populations and ecosystems that results from our use and manipulation of the environment
