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Environmental Issues Final
Terms in this set (91)
OBSTACLES TO IMPROVING ENERGY EFFICIENCY
-oil industry is the world's larger company (Exxon) it generates tremendous wealth
-here in U.S which is the world's leading consumer of oil and natural gases etc. but it is still a cheap fuel and relative to the price of gas that people are paying in other countries it is very cheap
-Individuals Matter: There is of course much that an individual can do to promote energy efficiency and reduce society's energy footprint. Recognizing that individual decisions, when they occur in mass, have the ability to affect major change: walk or bike, get a fuel efficient car, turn downy he thermostat and put on a sweater, plug all leaks in your home, get an energy audit in your house or office
renewable energy sources?
hydropower, solar, geothermal, wind, and biomass fuels
currently about how much of the world's commercial energy comes from renewable energy sources?
How much of the world's commercial energy comes from non-renewables?
85% - coal, oil, Nuclear power, and Natural Gas
How much of the U.S's commercial energy comes from renewable energy sources?
Are there benefits to converting to renewable energy sources?
the environmental, economic, and social benefits of converting to these forms of energy are enormous. In fact, humanity has no choice but to develop sustainable energy supply.
The world's leading renewable resource in terms of commercial energy production?
generation of electricity through moving water
How much of the world's electricity does hydropower produce?
How much of U.S commercial energy does hydropower produce
Leading Hydro power generating states in Order?
Quebec, then Ontario, then the U.S, and then Brazil
Where does most of the hydropower generated come from?
Disadvantages of Hydropower?
- Large land disturbance and displacement of people
- High CH4 emissions from rapid biomass decay in shallow tropical reservoirs
- Disrupts downstream aquatic ecosystems
- Habitat destruction
- people displacement
Result of Disadvantages of hydropower?
because of the disadvantages, industries like the world bank have pulled out their funding for big dam projects because of their controversial nature and because the best sites have already been damed - hydropower is actual today a low growth industry
- a plant has the capacity of up to 100 kilowatts
- rowing water is used to turn floating turbines or waterwheels generating enough electricity for a home, farm, or small village
- takes care of the big environmental issues
- being developed in rural areas with rivers
- some people try selling that extra power they make to energy companies or neighbors
Passive Solar Heating System
is becoming increasingly pervasive we have lots of small scale applications of it but the large plants are still under development
- you can use solar energy to do a lot of heating in a structure
- involves warming a building from the energy from the sun
- structures that have the ability to absorb and store heat energy from the sun
- involves carefully designing interior spaces so that they have solar energy collection
- Usually need to start from scratch
Active Solar heating system
Can be installed to a home - uses roof solar collectors
Advantages of Passive and Active Solar heating
net energy is moderate (active) to high (passive), very low emissions of CO2 and other air pollutants, very low land disturbance, moderate cost (passive)
Disadvantages of Passive and Active Solar heating
- need access to sun 60% of time during daylight
- sun can be blocked by trees and other structures
- high installation and maintenance costs for active systems
- need backup systems for cloudy days
Solar Thermal Systems- Commercial Solar Power Production:
these are currently in experimental use and are producing electricity in the U.S and other countries, it collects radiant energy from the sun and transforms it into high temperature heat
- most use systems of mirror that track the suns path through the sky throughout the day- systems use mirrors to concentrate sunlight and contains heat absorbing fluids which then boils water, creating steam and creating electricity ex) Andalusian countryside in Seville, Spain
advantages of Solar Thermal Systems:
moderate environmental impact, no direct emissions of CO2 and other air pollutants,
Solar Updraft Tower
the solar tower works like a giant inverted funnel, with a large gently sloping transparent outer section leading into a steep chimney-like neck in the center. greenhouse effects heat the air underneath, pulsing it faster and faster toward the chimney where turbines convert it to electricity
proposed building a solar plant in Australia that would be nearly 400m high and cover several kilometers. At its base is a solar collector — a 25,000 - acre, transparent circular skirt. The air under the collector is heated by the sun and funneled up the chimney by convection. As it rises, the air accelerate to 70mph, driving 32 wind turbines, which generate electricity for 200,000 homes
Why has the construction of solar updraft been delayed
Advantages of Solar Energy for High Temperature Heat and Electricity
- moderate environmental impact
- no direct emissions of CO2 and other air pollutants
- lower costs with natural gas turbine backup
Disadvantages of Solar Energy for High Temperature Heat and Electricity
- Low net energy and High Costs
- Needs backup or storage system on cloudy days
- High water use for cooling
Photovoltaic Cells (solar cells)
- converts solar energy directly to electricity, sunlight penetrates a thin transparent silicon semi - conductor, a very small flow of electrons is released, a small electrical current is produced which can power small things such as watches and calculators. - has enormous potential to power larger things- more money is going into this than solar thermal production
-want to use this on power plants - this is still experimental
Fastest Growing industry?
Solar cell energy
Worlds largest solar cell plants
Arizona power plant in Springerville and then Sacramento, CA
Advantages of Solar Cell plants
- moderate net energy yield
- little to no direct emissions of CO2 and other pollutants - easy to install more around and expand when needed
- competitive cost for newer cells
Disadvantages of Solar Cell plants
- need access to sun
- need electricity storage system or backup
- high costs for older systems but decreasing rapidly
- solar- cell power plants could disrupt ecosystems
-the cost of wind power has dropped so dramatically that it is currently the cheapest form of energy
- wind is an indirect form of solar energy wind is created by temperature gradients
- a wind turbine converts wind to electricity right at the turbine site - today's wind turbines are very large and very efficient
- a modern turbine can be 20 stories tall and can cost millions of dollars each to install
- part of the installation costs come from the large foundation
- no wobble in the structure or else the turbine will fall apart, this is often caused by poor construction
- this is the second fastest growing energy industry right behind solar cell manufacturing
How much electricity in the world is produced by wind power?
World's leader in wind power production?
China - surpassed the U.S in 2010
Where is the U.S in terms of wind power production?
Most Wind Reliant country and produces 50% of the world's wind turbines
How much of all electricity produced comes from wind?
How much did the world increase its wind energy production between 2000 and 2012?
the world increased its wind energy production 13 fold and in that same time there was a 25 fold increase in production in the U.S
Leader in the U.S for windpower
Texas - more than 40 commercial wind farms in Texas - has low population density across West Texas so it is good for it - Texas is a part of the Great Plains
Places good for windpower
- lots of areas good for wind power happen to be off shore
- best places for turbines: Ridge lines - Mountains, Great Plains b/c high average wind speed due to temperature gradients, offshore environments (very little friction and very significant temperature gradients)
-The Great Plains has tremendous potential for wind power generation - Saudi Arabia of Wind Power - if developed the Great Plains could potentially have electricity enough to power the whole U.S
NYS and windpower
15th in the U.S for wind potential and is 11th in the state for production as of 2013, there are presently 20 commercial scale wind farms in the state. Accounts for about 3% of NYS electricity production, enough to power 500,000 homes - on Atlantic Cost off of long island there is a lot of potential and Lake Ontario
Advantages of windpower
- moderate to high net energy yields
- widely available
- low electricity cost
- little or no direct emissions of CO2 and other air pollutants
- easy to build and expand
Disadvantages of windpower
- huge problem that wind power faces is transporting the energy - must build a transmission line
- Needs a backup storage system when winds die down
- low- level noise bothers some people
- can kill birds if not properly designed and located
For Industrial Wind Turbines - "Not in my back yard" - opposition by residents to a proposal for a new development because it is close to them, often with the connotation that while the development may be needed in society, it should be cited further away, or "Not in my backyard."
Solid Biomass Fuels
- wood logs and pellets
- Agricultural waste (stalks and other plant debris)
- Timbering wastes (branches, treetops, and wood chips)
-Animal wastes (dung)
- Aquatic plants (kelp and water hycinths)
- Urban wastes (paper, cardboard and other combustive materials)
conversion to gaseous and liquid biofuels
Synthetic natural gas (biogas) wood gas
Ethanol, Methanol, Biodiesel
Hydrogen gas as an energy source'. Producing hydrogen gas takes electricity heat or solar energy to decompose water, thus leading to a negative net energy yield. However, hydrogen is a clean-burning fuel that can replace oil, and other fossil fuels and nuclear energy, Using solar energy (Probably solar cells and wind turbines) to produce hydrogen from water also could eliminate most air pollution and greatly reduce the threat of global warming.
A Hydrogen Fuel Cell
takes in hydrogen gas and separates the hydrogen atoms' electrons from their protons. The electrons flow through wires to provide electricity, while the protons pass through a membrane and combine with oxygen gas to form water vapor.
The Hydrogen Problem:
Hydrogen gas (H2) is a rare compound in Nature. Water molecules (H2O) can be decomposed (split) to create H2 gas using electrolysis. Electrolysis requires energy inputs (electricity) to create H2 gas and the current technology is too expensive. Current technology produces a negative net energy yield.
A SUSTAINABLE ENERGY FUTURE:
Achieving a sustainable energy future requires:
immediately improving energy efficiency
increasing use of renewable sources- this will likely be a gradual trends given their supplies and artificially low prices fossil fuels will continue to be used for years to come- the challenge lies in meditating their harmful environmental impacts as we wean from them
Shifting our energy economy to a decentralized micropower system
A sustainable energy economy relying on the development of locally available renewable energy resources will require a switch away from a small number of centralized power plants to a decentralized system of smaller, more dispersed and diverse micropower systems
Why mustn't we be afraid to pursue a sustainable energy future?
b/t 1800 and 1970 the world shifted from a dependence on solid fuels like wood and coal to liquid and gaseous forms. innovation is one of the hallmarks of humankind and only economics and politics stand in the way of a new shift towards renewable energy resources such as solar and wind power and solar hydrogen revolution
- all life is dependent on the healthy functioning of the atmosphere
- about 75-55% of the mass is found in its inner most layer (troposphere)- this extends approximately 12 miles above sea level - gas rich - 78% Nitrogen, 21% Oxygen, smaller amounts of other gases like water vapor, argon, and CO2 - changes in concentration of these other gases is what causes the changes
- Ozone layer is found in the stratosphere and makes up 24% of the Earth's atmosphere
Warming of the Earth's lower atmosphere (troposphere) as a result of increases in the concentration of greenhouse gases primarily as a result of human activity
In order, the most abundant greenhouse gases in the Earth's atmosphere are . . .
water vapor, carbon dioxide, methane, nitrous oxide - all of these occur naturally
- of these four the last three are the most significant in terms of human production
How do greenhouse gases act?
- like the panes of glass - traps the heat - allows sun in and warmth energy and then traps it in place
Layer of greenhouse gases in the troposphere allows short wave infrared radiation to pass down to earth's surface which is absorbed and degraded and turned into long wave heat radiation - this rises back up into the atmosphere - the greenhouse gases then act like a pane of gas and traps the heat
Problem with the Greenhouse effect
widely believed that humans are increasing the concentration of greenhouse gases = global warming = warming of lower atmosphere (troposphere) as a result of human activity - amplifies the natural process
Rising Greenhouse Gas Concentration
- CO2: since 1959, when CO2 Concentrations first began to be directly measured, the concentration of atmospheric CO2 has increased by 14%.
-Other climate data - ice core- sampling, indicates that atmospheric CO2 concentration increases began in the 1850's. There has been a 28% increase in CO2 levels overall since 1850 (industrial revolution)
- most significant concentration = water vapor and CO2
water vapor impacts are very small and are usually not considered a greenhouse gas of concern - what we add is small to the atmosphere
Most essential in the heat trapping effect
Why is there more Co2 in the winter
Other Greenhouse gases
-Methane (CH4) levels have more than doubled since 1850 and Nitrous oxide (N2O) levels have increased by 20%
How much have GG concentrations increased since 1970?
- in total climatologists believe that GG levels in the troposphere are the highest they have been in 160,000 years
data that provides information in Co2 levels in the past- ice is used - layers in the ice represent past snow falls and determine atmospheric conditions at the time - small bubbles in the ice that can determine this
Causes of Greenhouse Gas Increases (Anthropogenic)?
1) Fossil Fuel Combustion - when we burn oil coal and natural gas we generate a significant amount of GG - nitrous oxide, carbon dioxide, methane
2) Deforestation - by reducing tree cover we are increasing CO2 emissions- less plants to take it in by reducing photosynthesis - burning of trees = transferring directly CO2 to the atmosphere
3) Commercial Agriculture - use of inorganic chemical fertilizers - releases nitrous oxides - meat production and cattle raising etc. - lots of methane is produced
Greenhouse gases and their human sources
Carbon Dioxide (CO2): fossil fuel burning, especially coal (70-75%) - deforestation, and plant burning ( 20-25%)
Methane (CH4) : Rice paddies, guts of cattle and termites, landfills, coal production, coal seams, and natural gas leaks from oil and gas production pipelines
Nitrous Oxide (N2O): fossil fuel burning, fertilizers, live stock wastes, and nylon production
Air conditioners, refrigerators, plastic foam - CFC use is being fazed out but it will take 50-100 years to come for the ozone layer to recover
Most significant contributors to GG emissions
Who accounts for the vast majority of current CO2 emissions?
world's largest CO2 polluters
China and the U.S
-China and the US alone produce more than half of the world's annual greenhouse gas emissions. But the USA's per capita emission of Co2 are about 5x that of China's
Countries with the highest per capita CO2 emissions?
Australia, U.S, and Canada
Rising surface temperatures
- Earth's climate fluctuates naturally - because of fluctuations in solar radiation, wobble in the Earths' axis, meteor impacts, volcanic events (produces huge volumes of particulate matter in the atmosphere and trigger climatic change), and ocean temp fluctuations
over the past 130 years - b/t 1906 and 2005 mean global temp have risen 1.4 degrees Faranheit - occurring in the absence of the natural triggers that could be producing this change - most of the increase happened in the 1980's
What do graphs of temperature changes show over the past 1000 yrs?
the 20th century shows a steep incline in temperature
-over the past 130 years - b/t 1906 and 2005 mean global temp have risen 1.4 degrees Faranheit - occurring in the absence of the natural triggers that could be producing this change - most of the increase happened in the 1980's
intergovernmental panel on climate change - every year they release an annual review on climate science - data what scientists are showing on greenhouse gas concentrations and other environmental factors - made up of more than 2k climate scientists in more than 100 countries around the world - work to summarize climate change
Anecdotal Evidence of Temperature increases
meteorological data suggesting that we are living in a very warm period
1) based on casual data, non statistical data ten warmest years on record since 1881 have all occurred since 1990 - 1998, 2005, 2010
2) over the past 50 years Arctic temps have risen almost twice as fast as those in the rest of the world and glaciers and floating sea ice are melting and shrinking at increasing rates
3) During the 20" century, the world's average sea level rose 19cm (7in)
The caution behind anecdotal evidence
Anecdotal meterological evidence is commonly used by non-experts to both support and disprove global warming
IPCC predictions of CO2 levels based on climate models
Using climate models, the IPCC predicts that at the present rate of increase in CO2 concentrations in the atmosphere, the Earth's mean surface temp is very likely to increase 2-4 degrees celsius (3.6-8.1 degrees farenheit) b/t 2005 and 2100 (90-99% confidence level)
- the most probably increase is 3 degrees celsius - 5.4 degrees farenheit
- this would really have a devastating impact on the Earth and lots of economic impacts - greenhouse gas concentration must go down
Possible beneficial effects of global warming
- some people think that humans would benefit from warmer winters and summers
- cost of heating would not be as high
- northern latitudes would be more hospitable to humans
- increase in rainfall would equal an increase in food production
- for every 1% increase in atmospheric carbon dioxide, the rate of photosynthesis will increase
- animals will move towards higher latitudes to match their old climates
Harmful Effects of Global Warming
- create better more suitable biomes for some animals but then other animals in other biomes would suffer
under sever climate change would be a likely trigger of an extinction episode - can't adapt to changing atmospheric conditions
Food and Water Supplies - climate changes will shift the climate belts polar - making equatorial areas less productive as they become drier and potentially more northern areas more productive as they are getting more rainfall - more productive for agriculture - could we shift the North American Bread basket into Canada, and have more northern areas in relation to the equator produce more of the agriculture - could reorient the food production system in such a way to make sure that food output continues coming out - the problem is that the areas that are getting the ideal climate might not have the proper soil conditions or surrounding conditions to grow the same food - you can't do that - in general scientist and other believe that food supplies would be significantly effected by the change in temperature - the places that are already struggling with food and water supply would be in an even worse situation - Abandoned cities? widespread migration, starvation, disease, war? Collapse of agricultural economies?
Rising Sea Levels- changes in avg. sea levels over the past 250,000 years base on data from ocean cores -melting ice (1/3 Polar Ice & Glaciers) 20% loss in Arctic Sea once since 1979 - - ice serves to reflect radiation back into space - more heat energy absorbed - loss— and the biggest factor - thermal expansion of water - water expands when heated (2/3 of sea level increase) - flooding out of low lying coastal zones - human displacement - destruction of cities - forced adaptations - coastal areas contain 1/3 of the world's populations - huge population centers would be devastated - lots of the world's arable land would be lost - pollution from flooding - biodiversity impacts - coastal estuaries, wetlands, coral reef loss
Biodiversity Impacts - if we shift climates we shift biomes - the majority of the world's biomes would change - animals would shift themselves into new climate belts assuming they could get up and move themselves - animals that could not move quickly enough would die out - Northern migrations of forests would have to occur - ecosystems already under threat would be most disrupted - mass extinctions - warming would reduce biodiversity
Extreme Weather Changes - more heat on the Earth's source would create higher wind speeds and more clashing warm and cold air - increase intensity in the number of damaging weather events like hurricanes, tornadoes, blizzards - violent, extreme, weather - more people would be dying from this - then the economy would also be impacted like the insurance industry
Human Health Impacts - more people dying of heat exhaustion, more violent weather that would kill people, if we disrupt food and water supplies there will be more starvation and diseases
Dispute: Are we really experiencing global warming - Does Causation= Correlation
it has not yet been scientifically proven that human are causing it
atmospheric concentrations of CO2, and the atmospheres average temperature for the period 1880-2009. The data shows a strong positive correlation between these two variables but a small number of climate scientists do continue to argue that a casual relationship - these variable have not yet been firmly established - correlation between rising greenhouse gases and rising temperatures
How much warming is likely to occur and what are the effects?
lots of scientific uncertainty surrounding this
a # number of natural and human factors how feedback mechanisms interact with each other may amplify of dampen global warming
ex) CLOUD COVER- believed that if we warm the surface of the Earth as a result there would be more evaporation and cloud cover - increase rates of evapotranspiration. but certain types of cloud can have an isolating effect and other types of cloud can shade the Earth from solar radiation - more ex 2) PHOTOSYNTHESIS
Uncertainty surrounding the role of these and many other climate feedback mechanisms is responsible for the wide range of climate predictions scientists are producing
it remains a fact - the climate community has not come to an agreement not he scope of future temperature increases — the amount of warming that is likely to occur. Subsequently , the likely impacts of GW remain in question
GW skeptics have latched on to this uncertainty arguing that, "there is no scientific consensus on global warming"
Is this accurate? is there no scientific consensus on global warming
The scientific consensus of global warming
consensus: does not mean unanimity, it means that most agree - a judgement arrived by most of those concerned
Cook 2013 study of global warming consensus:
scientists estimated 11, 944 peer reviews climate changed articles finding that among those taking a position of anthropogenic global warming. 97.1% endorsed the consensus positions that humans are causing global warming
- This study showed that the number of studies rejecting anthropocentric global warming is decreasing - a vanishingly small proportion of published research
The vast majority of climate scientists agree on the following issues
- the physics of the greenhouse effect
- since the beginning of the industrial revolution, humans have dramatically increased levels of greenhouse gases in the troposphere
- Over the 140 years of weather observations, global surface temperature have been rising
Most importantly, the earth's troposphere is warming, mostly because of human actions. Global warming is occurring
Does siding with the scientific majority and erring on the side of caution make more sense than denying the likely existence of global warming?
Hoax Approach/ "Wait and See" strategies : preparing for the possibility of the worse case scenario happening but not actually doing anything in the process
Precautionary/ "no regrets" strategies: even if we are wrong about global warming these are things that we still have to do anyways so might as well do them- whether or not global warming is real we still have to do these things
Solutions to Global Warming
1) Reduce Greenhouse Gas Emissions - reduce concentrations in the troposphere and we need a preventative approach
2) Improve Energy Efficiency - we need to increase this - fossil fuel combustion is the leading source of greenhouse gas emissions
3) Develop Renewable Energy Resources
4) Tax or Cap Greenhouse Gas Emissions- tax carbon, cap and trade initiatives: political policy approaches
carbon and energy taxes trade offs
easy to implement and there would be a clear price on carbon
- is a regressive tax - makes fuel more expensive and it does impact people low on the socioeconomic
-does not guarantee lower emissions
vulnerable to loopholes
- Simple to administer
- clear price on carbon
- covers all emitters
- predictable revenues
Cap and Trade policies trade offs
- egulation of sulfur dioxide and nitrous oxides as it correlates with acid rain
- get credits and it does well in getting companies to reduce acid rain generating pollutants
- can trade these to other people - free market trade system ex) EU has one - their cap is slowly moving down as they get the people to work with them in reducing emissions
- Low expense for consumers
- Record of success
-Revenues not predictable
-Vulnerable to cheating
- Rich polluters can keep polluting
-Puts a valuable price on carbon
another approach - involves carbon sequestration technology that involves capturing and storing CO2 not letting it get out into the atmosphere solutions:
- plant forests that will take the carbon - assists in the process
- using switch grafts as possible sequestration units- today they mostly refer to industrial
- sends CO2 into an underground mine or deep into the ocean where it can dissolve
- mostly experimental use - very expensive to operate
- many nations are implementing carbon taxes to attempt to make these
-Oil fields, gas fields, saline formations, unminable coal seams, and saline-filled basalt formations have been suggested as geological storage sites. Various physical (e.g., impermeable caprock) and geochemical trapping mechanisms would prevent the CO2 from escaping to the surface. CO2 is sometimes injected into declining oil fields to increase oil recovery.
Examples of Carbon Sequestration
As of 2007, four industrial-scale storage projects are in operation. The Sleipner Gasfield, is the oldest project (1996). Located in the North Sea, Norway's StatoilHydro strips carbon dioxide from natural gas and disposes the carbon dioxide in a deep saline aquifer. The carbon dioxide is a waste product of the field's natural gas production. Storing it underground saves Statoil hundreds of millions of Euro in avoided carbon taxes.
There is, of course, much that an individual can also do to reduce CO2 and other greenhouse gas emissions.
Recognizing that individual decisions, when they occur in mass, have the ability to affect major change.
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