envs 100

What is a main problem associated with food and agriculture today?

- Unequal production of food - Unequal consumption of food - Overconsumption of resource intensive foods - Diversion of food to other products and waste

What environmental problems could be addressed if China increased their use of nuclear energy production and decreased use of coal?

A decrease in pollution from sulfur, heavy metals and carbon dioxide.

Name one pro and one con to utilizing wind energy.

A: Pros ● Cost is very competitive with fossil fuels ● Renewable ● Almost no pollution once built Cons ● Reliability ● Can require some storage mechanism to compensate for reliability ● Aesthetics ● Killing of bats and birds

What are the two types of solar energy and how are they used?

Active solar: using technology to convert the sun's energy directly to electricity (e.g. photovoltaics) Passive solar: using the sun's energy to directly heat a building.

Which of these use or extraction techniques is correctly matched with the fossil fuel for which it would perform the most environmental benefit?

Applying carbon sequestration techniques during the burning of coal.

Do we currently produce enough food to feed all 7 billion people on the planet today? Please explain your answer.

Arguably Yes - we produce enough food to feed everyone on the planet but there are problems with transportation, storage, distribution, nutritional content, and cost of food.

Which of the following is the main technical challenge with running a nuclear reactor?

Avoiding the production of too much heat and/or explosive gases.

Why is climate change an "intergenerational equity" problem?

Because the climate change impacts of greenhouse gas emissions aren't felt for 50 years or more after those GHGs were emitted -- which means one generation benefits from the burning of fossil fuels, while later generations pay the price.

what greenhouse gas does not naturally occur in the atmosphere?

CFCs

During a catastrophic nuclear meltdown, certain changes occur in the reactor that can lead to the loss of containment of the materials in the reactor core. Which of the following might be a reasonable response to this worst-case scenario?

Increase the flow of coolant and add more neutron absorbing rods into the reactor.

Imagine you are home for a family dinner and the next door neighbor goes into a long monologue about how the US needs to develop nuclear power to break our dependence on foreign energy sources. What's wrong with this idea?

Nuclear energy would just displace domestic coal and natural gas.

Which of the following is NOT a concern when deciding whether to increase nuclear power generation on a global scale?

Nuclear power produces more CO2 than coal-fired power plants.

If you were in charge of air pollution regulations in Colorado and could choose to generate energy from any non-renewable source, which of the following lists best represents the best to worst fuel choices if your goal is to reduce both greenhouse gas and air pollution emissions?

Nuclear>natural gas>coal

How does a non-renewable energy resource differ from a renewable energy resource?

Renewable: Use rate is less than replacement rate. Non-Renewable: Use rate is higher than replacement rate. Examples: Coal, solar... etc.

What does the US currently do with its high level nuclear waste?

Store it above ground in temporary facilities.

Although extracting petroleum from shale oil is highly energy and resource intensive, why would companies such as Shell Oil want to develop this energy source?

The products of shale oil are easily integrated into our current system of energy use.

Why will we likely emit more CO2 per unit of energy consumed as we use more unconventional fuel sources in the future such as tar sands and oil shale?

Unconventional fuels often take more energy to extract, which uses more fossil fuels and hence creates more CO2.

the younger dryas involved a cooling of 10 degrees celsius in the north atlantic region that occurred over a period of _____. this cooling event was caused by _____?

a decade; the melting of large ice sheets in north america

why is hydrogen hard to store?

as a liquid, it needs to be stored at very cold temperatures, and as a gas, the molecules tend to escape through tiny cracks in the containers

what scenario would result in a negative feedback loop?

as atmospheric carbon dioxide level and temperature increase, more carbon is available for plants to take up during photosynthesis, causing increased uptake of carbon dioxide by plants

This type of energy comes from the organic molecules of recently living plants or algae or from animal manure.

biomass

Suppose that in the future, solar energy became extremely inexpensive, and air pollution was the most critical concern. Based on air pollution produced, which fuel would be best to phase out?

coal

Which fossil energy source is the most plentiful on Earth?

coal

do light or dark colors have the largest absorption of solar energy and reradiation of this energy in longwave (infrared) forms?

dark

how much CO2 emissions could be reduced or increased by using biofuel instead of gasoline?

decreased emission of 1.5 kg CO2

what would happen to global temperatures if there were no greenhouse gases in the atmosphere?

earth would be very cold

general circulation models (GCMs) suggest that?

earth's recent warming trend cannot be explained solely by natural forcings

even if the production of solar and wind energy increases quickly, these technologies are likely to play a minor role in the global energy supply over the next few decades. why?

energy demand is growing fast, and these renewable energy sources are currently small relative to fossil fuels

what is not associated with the warmest periods of the past 500 million years of earth's history?

extinction rates far exceeding modern day extinction rates

what is the difference between first and second generation biomass fuels?

first generation fuels are made from plant materials that can also be used as food second generation fuels are made from non-food plant materials

which combination could provide 100% renewable energy mix? base demand refers to the period of the day when the most energy is used-usually in the afternoon when many people are at work.

hydroelectric power provides energy to meet the base demand, solar energy us used to meet peak demand during the day, and wind energy is used at night

what is a potential regional benefit of a slight increase in atmospheric temperatures during the 21st century?

improved agriculture would allow for increased food production

precipitation is expected to _____ across the globe during the 21st century, and areas over water are expected to experience a _____ temperature increase that areas over land

increase; smaller

how does geothermal heat pump (residential) technology work?

it takes advantage of the relatively constant temperature of the surface earth to cool the house in the summer and warm it in the winter

what is an environmental impact resulting from concentrated solar power plants?

land disturbance, impact on wildlife, potential use of water in drought-prone areas

while most of the major rivers in the united states could not support additional hydropower dams, what statement describes a viable decentralized alternative that would still harness hydropower?

micro-hydropower facilities could be installed that generate a lesser amount of electricity with low environmental impacts

as polar sea ice disappears due to warming, this will result in _____ at earth's surface, which then functions as a _____ to climate change

more energy absorption; positive feedback

analyses indicate that only 2% of the net climate forcing of the atmosphere since 1750 is a result of?

natural changes in solar energy reaching earth

What non-renewable energy source has the least greenhouse gas and air pollution emissions?

nuclear

what is not a major environmental benefit of wind energy?

protection of wildlife and aesthetics

what is the difference between renewable energy and sustainable energy?

renewable energy resources cannot be used up, whereas sustainable energy can meet current and future needs without impacting future generations

what would be required to make hydrogen part of a renewable energy system?

renewable energy would need to be used to make hydrogen gas

greenhouse gases trap heat in the atmosphere when?

shortwave radiation from the sun is absorbed by earth's surface and reradiated as infrared

one day you are chatting with a friend about the environmental benefits of integrating large-scale renewable energy into the current power generation system. your friend is skeptical; he argues that wind farms kill birds, solar facilities interrupt animal migrations and habitats, and hydropower ruins river habitats-how could all of that possibly be environmentally friendly? what argument could you respond with to demonstrate some of the positive benefits you were thinking of and that might balance the points that your friend mentioned?

the integration of renewable energy on a large scale could drastically reduce CO2 and other pollutants in the air, which are currently damaging the environment for humans, plants, and animals alike at an alarming rate by causing climate change and widespread contamination

scientists use several types of analysis to demonstrate that human activities are responsible for warming. what is not an analysis that shows that human activity is responsible for warming?

the measurement of global temperatures using satellite observations to determine that global temperatures are rising

Which of the following statements is NOT a reason why fossil fuels are so cheap?

there are so many fossil fuels available to everyone around the globe that there is no major economic demand for them to drive the prices up.

which is not a proxy record of global temperature?

thermometer readings

what is the difference between traditional biomass fuels and liquid biomass fuels?

traditional fuels are burned directly while liquid fuels are synthesized from plants and algae

urban heat islands occur in metropolitan areas where the air temperature is several degrees warmer that the surrounding rural areas. how can the concept of a climate forcing be used to explain the urban heat island phenomenon?

urban areas contain cast expanses of paved surfaces and other surfaces that absorb shortwave radiation and reradiate it as heat. rural areas tend to be more heavily vegetated and so reflect more shortwave radiation

what is an example of an aerosol?

volcanic ash

for a geothermal heat pump to work, the ground has to be________ than the air in winter and _________ that the air in the summer

warmer, cooler

how is electricity produced from moving water in a hydropower dam?

water is store as potential energy snd turned into kinetic energy as it moves downhill through the dam and turns a turbine creating electricity

which area has experienced the greatest surface temperature increase since 1900?

siberia and northern canada

Which of the following statements about the relationship between traditional fossil fuels and unconventional fossil fuels is true?

Traditional fossil fuels are located in large pockets relatively near to the earth's surface, whereas unconventional fuels are present in deeper or smaller pockets and require new technology or greater expensive to extract.

Why can we count on energy demand increasing globally?

"Haves": ~1.5-2 billion people are affluent and use massive amounts of energy "Soon-to-Haves": ~2.5-3 billion people are in rapidly rising economies and use an increasing (but still small) amount of energy. Per capita use is still far behind! "Have Nots": ~2-3 billion people live in areas with very little energy. We can count on the "Soon-to-Haves" group driving energy demands up, as members of that group aspire to more energy-intensive lifestyles.

some people argue that replacing gasoline with biofuels is an important step in transitioning from fossil fuels to renewable energy that must be completed right away, especially because we have the technology and products to do it. while this argument may hold so validity, what drawbacks may these people be overlooking when making this argument?

-mass production of some biofuels could potentially limit food supplies -it requires a lot of energy to convert biomass into biofuel -regular gasoline engines cannot use pure biofuels without being converted (and biodiesel can only be used in diesel engines)

What limits our ability to change the way we use energy? Provide one major reason.

1. Infrastructure and investment - takes time and money - Path Dependency 2. Embedded economic interests - status quo always has more defenders than uncertain future technologies - Politics 3. Effectiveness and reliability - what we have works. It's not perfect but... - Risk

Globally speaking, what is a potential downside to climate change?

Downsides: ● Changes in weather patterns threaten to decrease our food and water supplies ● Winners and losers among countries potentially causing conflict ● Pace of change can be beyond the ability for natural adaptation ● Less water for the Western US ● Higher sea level costly and disruptive

Countries meet their energy needs differently. The U.S. relies mostly on ________, while France relies mostly on ____________. What are two factors that contribute to countries' energy choices?

Fossil fuels, nuclear. Relative national availability of energy resources; national ethics and societal priorities. (Some other examples for convo: Iceland and geothermal; Norway and hydropower; Germany's use of solar power even though it has much lower solar potential than the U.S., etc.

What is geoengineering and provide an example.

Geoegineering is using a range of technologies from activities to sequester carbon dioxide to physically controlling the earth's energy balance (i.e. climate engineering). Possible examples include removing carbon dioxide from smoke stacks before it enters the atmosphere, using solar reflectors to keep energy from entering the atmosphere, or growing more trees to sequester carbon dioxide.

which of the following is emitted as a result of the electricity generation in a hydrogen fuel cell?

H2O

Which of the following renewable energy sources provides the most reliable (or consistent) source of energy and why?: Solar, Wind, Hydro

Hydropower, because dams can run at any time of the day (unlike solar) and in any weather (unlike wind).

Define mitigation and adaptation in the context of climate change and give an example of each.

Mitigation means taking steps to reduce or eliminate the causes of climate change ("protecting the climate from us") Adaptation is a human process that leads to a reduction in the risks associate with changing climate ("protecting us from the climate")

How can we calculate the lifetime of a fossil fuel reserve? Also, what are two different categories of "reserves" for fossil fuels?

Lifetime = Reserves/Production Rate. Proven reserves (known to exist and economically recoverable) vs. estimated reserves (what we think is there and can recover)

The technology used to carry out hydraulic fracturing of subsurface fossil fuel deposits has only been widely available for a couple of decades. What has happened to natural gas prices and availability as the result of the use of this technology?

Natural gas has become cheaper and more available because the use of this technology has greatly increased the amount of gas that can be extracted.

Tar sands are currently an economically viable and widely used unconventional fuel source. What non-renewable fuel source do tar sands replace? Why?

Oil. The sands are heated, and crude oil separates from the sand.

Assuming that there are abundant quantities of fossil fuels in the ground, when the prices of these fuels rise, do reserve estimates increase, decrease, or stay the same? Why?

Reserve estimates increase because when we pay more for fossil fuels, we are able to extract from reserves that were simply too expensive to access before.

Nuclear power is promising in terms of energy production with no greenhouse gas consequences, but what are the three major drawbacks to nuclear power?

Safety of power plants; Storage of wastes; Proliferation of nuclear weapons

Which of the following is NOT true about the US' switch over to natural gas as a major source for electricity generation rather than coal?

There are larger reserves of natural gas in the ground than coal.

Globally speaking, what is a potential upside to climate change?

Upsides: ● Higher plant productivity likely ● Globally, more precipitation ● Areas once inhospitable now reachable (Arctic)

Explain the difference between breeding process for traditional crops and genetically modified (GM) crops List one argument in favor and one argument against GM crops.

Traditional breeding uses sexual reproduction where as GM breeding alters the crops' genetic make-up through modern genetic techniques. (b) Pros: 1. Could reduce herbicide/pesticide use (e.g. Bt corn) - not much evidence for this. 2. Can increase yields - some evidence 3. Can be used to resist disease. 4. Could reduce fertilizer use, improve drought resistance. (maybe in the future) 5. One of the few ways we can get more out of the land we already have (at least in the developed nations) Cons: Will affect non-target organisms (e.g. Bt corn will kill butterflies). Yes 2. Genes can move from one organism to another (herbicide resistance can move to weeds). Yes 3. Increases corporate control over agriculture (must buy seeds every year). Probably true, but some non-profit GMO work beginning. 4. Concern for human health. (Uncertain)

As developed countries grow economically, what fundamental shift to you tend to see in their citizen's diets, and what impacts does this have on agriculture and natural resources?

Transition to more of a meat-based diet, as opposed to a plant-based diet. Meat production requires more resources (e.g., animal feed production and irrigation), and can have increased negative environmental impacts.

What is most of the oil in the US used for? What is most of the natural gas in the US used for?

Transportation; electricity generation and domestic (home) use

one concern with a warming climate is how it will affect ecosystems. in one scenario that scientist are studying, a warming arctic climate will melt permafrost, which will then stimulate the decomposition of frozen organic matter, thus increasing the release of large quantities of CO2 and CH4 and causing further warming of the climate. this scenario would be an example of what?

a positive feedback loop

what is not a barrier to incorporating renewable energy techniques at a large scale in the united states?

no opportunities exist to build renewable energy resources in the united states

List one benefit and one problem with energy generation from natural gas in the US.

abundant resource in US and lower CO2 emissions than coal; Problems: fracking issues, natural gas still produces CO2 emissions.

the thawing of permafrost from rising temperatures in the arctic is expected to?

accelerate climate change via positive feedback loop as carbon dioxide and methane are released from these soils

what is not a negative environmental effect of hydropower?

air pollution

what most accurately describes average global temperature changes since 1990?

average global temperatures climbed during the early 1900s, with a 20 year period of relative stability between 1950 and 1970

what is nota mitigation strategy to deal with climate change?

building sea walls to protect coastal areas from storm surges

how could batteries help address some limitations of renewable energy?

by storing energy

what greenhouse gas is short lived and exhibits the most variation in atmospheric concentrations from season to season?

water vapor

list molecules in order from most to least powerful in terms of their climate-forcing impacts during the 20th century

carbon dioxide > methane > halocarbons > aerosols

what is not a component of milankovich cycles?

changes in the distance and shape of the moon's orbit around the earth

What two countries are the world's largest CO2 emitters overall?

china and u.s.

what scenario is projected by the IPCC if we were to dramatically reduce our global greenhouse gas emissions immediately?

continued global warming, but less warming that would occur without greenhouse gas reduction

what is the main drawback to geothermal heating and cooling of buildings?

cost of installation

in what ways do the government policies inhibit widespread use of sola and other renewable energy sources?

current policies are built around a fossil fuel energy system

you know that u.s. electricity grid; in fact, it is actually separated into three major grids with few connections between sections. however, you are wondering why these three major grids don'y just become mini-grid systems that remain centralized but run completely on the renewable resources that are available in each respective section. what major issue still stands in the way of this plan to implement renewable power on a large, centralized scale in the future?

energy from many renewable sources, such as solar and wind, are only available at certain times and are difficult to store for use during "off" times, regardless of the size of interconnectivity of the grid

what statement is an accurate characterization of a potential benefit of second generation biomass fuels as an energy source?

second generation biomass fuels would not require the use of food crops like corn and sugar cane

the sun releases energy across the electromagnetic spectrum. which forms of electromagnetic energy from the sun affect climate?

shortwave radiation, such as visible light

how does concentrated solar thermal power differ from solar photovoltaic systems?

solar photovoltaic power converts solar energy directly into electricity concentrated solar thermal power uses heat to turn a turbine

what describes an example of the use of passive solar?

south facing windows that allow sunlight during the winter

the combustion of coal produces what? which tends to have a cooling effect on the climate

sulfate aerosols

what statement best explains why the widespread use of solar is limited at present?

sunlight is only available part of the day and it is expensive to produce electricity from solar

what line of evidence most strongly suggest that current global climate change is a result of increased levels of greenhouse gases in the atmosphere rather than increased solar radiation?

temperatures in the stratosphere are actually decreasing, suggesting that the atmosphere is not warming because of increased solar radiation

what most accurately describes global temperature patterns over the past 12,000 years?

temperatures increased over a period of 2-3 thousand years, leveled off, declined gradually over the past sever thousand years, and then recently increased rapidly to the highest level of that time period

based on your understanding of projections of future climate change, what statement is most true?

the amount of 21st century warming will depend to a large degree on the speed with which we can reduce the emission of greenhouse gases

what describes the global warming potential of gas?

the amount of heat a gas can trap in the atmosphere in a certain amount of time

how quickly is the use of wind energy growing?

the amount of power generated by wind globally doubles every three years

what generates the heat produced deep inside earth?

the decay of radioactive elements

why is there concern about the impact of biomass fuel production on food prices?

the diversion of food crops to energy production decreases the amount of food available for human consumption

what is the main reason that wind cannot be used to provide all of the energy needed to meet electricity needs?

the grid cannot store electricity, and the wind is an intermittent source of energy

what is not predicted to directly result from rising global temperatures?

the increased acidity of the ocesn

albedo is the measure of the surface's ability to reflect solar radiation. what has the highest albedo?

the snow on top of a dormant volcano

which of the following is a major barrier to the increased use of solar photovoltaic energy in homes?

there are large up-front costs to solar PV installation

what best characterizes the size and current status of geothermal resources in the united states?

there is great resource potential in the country but relatively little new development

how would you characterize the potential for new large-scale hydropower projects in developed countries?

there is little potential for further large-scale hydropower development in developed countries since many of the large rivers have already been dammed

some people have said that water vapor is a more powerful greenhouse gas that industrially produced gases such as CO2, and for this reason, we shouldn't worry about the rising concentrations of industrially produced greenhouse gases. what is wrong with this claim?

water vapor has a short residence time in the atmosphere and therefore cannot serve as a forcing for climate change

how do we know what global temperatures were before we had a widespread network of thermometers?

we can determine this by looking at the patterns of tree rings or the isotopes of certain elements that vary with temperature

one of the projections of the effects of climate change is an increase in the intensity of extreme events such as floods and droughts. would this be important to human society?

yes, extreme events are difficult to plan for and place a large amount of stress on human systems and infrastructure

What is one of the four main reasons an overall yield from agriculture has increased in the last 100 years?

● mproved crop varieties ● Fertilizer use ● Advances in pest control ● Irrigation

Name two limitations to widespread energy production for solar energy.

● production is limited by cloudiness or darkness -land disturbance caused by large solar fields ● distribution is limited by a fragmented grid and limited ability to store/transport energy