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Wednesday, October 6, 2010

Greenhouse gases and society

Give credit to Nick Hopwood and Jordan Cohen


  Greenhouse gases naturally blanket the Earth and keep it about 33 degrees Celsius warmer than it would be without these gases in the atmosphere.  This is called the Greenhouse Effect.  Over the past century, the Earth has increased in temperature by about .5 degrees Celsius and many scientists believe this is because of an increase in concentration of  the main greenhouse gases:  carbon dioxide, methane, nitrous oxide, and fluorocarbons.  People are now calling this climate change over the past century the beginning of Global Warming.  Fears are that if people keep producing such gases at increasing rates, the results will be negative in nature, such as more severe floods and droughts, increasing prevalence of insects,  sea levels rising, and Earth's precipitation may be redistributed.  These changes to the environment will most likely  cause negative effects on society, such as lower health and decreasing  economic development.  However, some scientists argue that the global warming we are experiencing now is a natural phenomenon, and is part of Earth's natural cycle.  Presently, nobody can prove if either theory is correct, but one thing is certain; the world has been emitting greenhouse gases at extremely high rates and has shown only small signs of reducing emissions until the last few years.  After the 1997 Kyoto Protocol, the world has finally taken the first step in reducing emissions. 

The Greenhouse Effect
    The "greenhouse effect" is the heating of the Earth due to the presence of greenhouse gases.  It is named this way because of a similar effect produced by the glass panes of a greenhouse.  Shorter-wavelength solar radiation from the sun passes through Earth's atmosphere, then is absorbed by the surface of the Earth, causing it to warm.  Part of the absorbed energy is then reradiated back to the atmosphere as long wave infared radiation.  Little of this long wave radiation escapes back into space;   the radiation cannot pass through the greenhouse gases in the atmosphere. The greenhouse gases selectively transmit the infared waves, trapping some and allowing some to pass through into space. The greenhouse gases absorb these waves and reemits the waves downward, causing the lower atmosphere to warm.(www.eb.com:180)
Diagram to help explain the process of global warming and how greenhouse gases create the "greenhouse effect"
www.eecs.umich.edu/mathscience/funexperiments/agesubject/lessons/images/diagrampage.html

Greenhouse Gases
This graph shows the distribution of GHG in Earth's atmosphere. Carbon Dioxide is clearly the majority.
www.abcnews.com/sections/us/global106.html
 
Carbon Dioxide
       Carbon Dioxide (CO2) is a colorless, odorless non-flammable gas and is the most prominent Greenhouse gas in Earth's atmosphere.  It is recycled through the atmosphere by the process photosynthesis, which makes human life possible. Photosynthesis is the process of green plants and other organisms transforming light energy into chemical energy.  Light Energy is trapped and used to convert carbon dioxide, water, and other minerals into oxygen and energy rich organic compounds.  (Encyclopaedia Britannica Volume 25)    Carbon Dioxide is emitted into the air as  humans exhale,  burn  fossil fuels for energy, and deforest the planet.  Every year humans add over 30 billion tons of carbon dioxide in the atmosphere by these processes, and it is up thirty percent since 1750 (www.envirolink.org/orgs/edf/sitemap.html).    An isolated test at Mauna Loa in Hawaii revealed more than a 12% (316 ppm in 1959 to 360 ppm in 1996) increase in mean annual concentration of carbon dioxide. Mauna Loa, located in Hawaii,  is the worlds largest volcano at 40,000 cubic km and 4,170 meters above sea level.  (Encyclopedia Britannica Volume 27) .  Ice core samples have also shown a dramatic increase in carbon dioxide levels.  Drilling deep into glaciers and polar ice caps and taking out samples of ice, then melting the ice and capturing the gas has shown an increase in carbon dioxide concentrations over the past 100 years.  Ice core samples are essentially "drilling through time", because the deeper the ice is, the older the ice is.
     In 1996, carbon dioxide world emissions increased by 2.8%.  The U.S. reported a 3.3% increase in CO2
 concentrations. The U.S. continues to emit more than any other country in the world, accounting for 25% of all emissions. The European Union had an increase of 2.2%, much larger than a small increase of 1.1% in 1995.  Eastern Europe had a decreasing rate of -2.4%.  China's increase in 1996 was 4.7%.(http://infoweb.magi.com/~dwalsh/wfsesr.html)
     Fossil Fuels were created chiefly by the decay of plants from millions of years ago. We use coal, oil and natural gas to generate electricity, heat our homes, power our factories and run our cars.  These fossil fuels contain carbon, and when they are burned, they combine with oxygen, forming carbon dioxide.  The two atoms of oxygen add to the total weight.  The World Energy Council reported that global carbon dioxide emissions from buring fossil fuels rose 12% between 1990 and 1995. (www.eb.com:180)  The increase from developing countries was three times that from developed countries. Middle East carbon dioxide emissions from burning of fossil fuels increased 35%, Africa increased 12%, and Eastern Europe increased rates by 75% from 1990-1995.
 This graph shows the increase of carbon dioxide in the air over the past few centuries
 
Ice Core samples and samples at Mauna Loa, Hawaii, reveal an increase CO2 concentrations
Pie chart shows how CO2 is produced
www.envirolink.org/orgs/edf/sitemap.html
Cars also contribute to CO2 in the atmosphere.
www.abcnews.com/sections/us/global106/index.html
       Deforestation is another main producer of carbon dioxide.  The causes of deforestation are logging for lumber, pulpwood, and fuel wood.  Also contributing to deforestation are clearing new land for farming and pastures used for animals such as cows.  Forests and wooded areas are natural carbon sinks.  This means that as trees absorb carbon dioxide, and release oxygen, carbon is being put into trees.  This process occurs naturally by photosynthesis, which occurs less and less as we cut and burn down trees.  As the abundance of trees declines, less carbon dioxide can be recycled.  As we burn them down, carbon is released into the air and the carbon bonds with oxygen to form carbon dioxide, adding to the greenhouse effect.  About 860 acres, the size of Central Park in New York, is destroyed every 15 minutes in the tropics.
Deforestation and Forest Fires contribute to an increase in CO2 levels
www.envirolink.org/orgs/edf/sitemap.html
 
 The Amazon Rain Forest, which is in parts of Brazil, French Guiana, Suriname, Guyana, Venezuela, Nicaragua, Costa Rica, Panama, Columbia, Ecuador, Peru, and Bolivia, is subjected to a great deal of deforestation
www.abcnews.com/sections/us/global106.html

 Methane
      Methane is a colorless, odorless, flammable gas.   It is formed when plants decay and where there is very little air.  It is often called swamp gas because it is abundant around water and swamps.  Bacteria that breakdown organic matter in wetlands and bacteria that are found in cows, sheep, goats, buffalo, termites, and camels produce methane naturally.  Since 1750, methane has doubled, and could double again by 2050.  Each year we add 350-500 million tons of methane to the air by raising livestock, coal mining, drilling for oil and natural gas, rice cultivation, and garbage sitting in landfills.(www.envirolink.org/orgs/edf/sitemap.html)  It stays in the atmosphere for only 10 years, but traps 20 times more heat than carbon dioxide.
Methane is on the rise since 1750
www.envirolink.org/orgs/edf/sitemap.html
      Rice cultivation has developed into a large business; farmland has doubled in the past 45 years.(www.envirolink.org/orgs/edf/sitemap.html)   It feeds 1/3 of the World's population.  It grows mostly in flooded fields, where bacteria in waterlogged soil releases methane.
     Livestock such as cows, sheep, goats, camels, buffaloes, and termites release methane as well.  Bacteria in the gut of the animal break down food and convert some of it to methane. When these animals belch, methane is released.  In one day, a cow can emit ½ pound of methane into the air.  Imagine 1.3 billion cattle each burping methane several times per minute!
Cows such as these contribute a large amount of methane to the air.
www.envirolink.org/orgs/edf/sitemap.html

Nitrous Oxide
     Nitrous oxide is another colorless greenhouse gas, however, it has a sweet odor .  It is primarily used as an anesthetic because it deadens pain and for this characteristic is called �laughing gas.�  This gas is released naturally from oceans and by bacteria in soils.  Nitrous oxide gas risen by more than 15% since 1750.   Each year we add 7-13 million tons into the atmosphere by using nitrogen based fertilizers, disposing of human and animal waste in sewage treatment plants, automobile exhaust, and other sources not yet identified.  It is important to reduce emissions because the nitrous oxide we release today will still be trapped in the atmosphere 100 years from now. (World Book Volume 13)
Nitrous Oxide has been on the rise since 1750
www.envirolink.org/orgs/edf/sitmap.html
     Nitrogen based fertilizer use has doubled in the past 15 years.  These fertilizers provide nutrients for crops; however, when they breakdown in the soil, nitrous oxide is released into the atmosphere.  In automobiles, nitrous oxide is released at a much lower rate than carbon dioxide, because there is more carbon in gasoline than nitrogen.

Fluorocarbons
    Fluorocarbons is a general term for any group of synthetic organic compounds that contain fluorine and carbon.  Many of these compounds, such as chlorofluorocarbons(CFCs), can be easily converted from gas to liquid or liquid to gas.  Because of these properties, CFCs can be used in aerosol cans, refrigerators, and air conditioners.  Studies in the 1970s showed that when CFCs are emitted into the atmosphere, they break down molecules in the Earth's ozone layer (World Book).  Since then, the use of CFCs has significantly decreased and they are banned from production in the United States.
The substitute for CFCs are hydrofluorocarbons (HFC's).  HFCs do not harm or breakdown the ozone molecule, but they do trap heat in the atmosphere, making it a greenhouse gas, aiding in global warming.  HFCs are used in air conditioners and refrigerators.  The way to reduce emissions of this gas is to be sure that in both devices the coolant is recycled and all leaks are properly fixed .  Also, before throwing the appliances away, be sure to recover the coolant in each.
 
Refrigerators and  Air Conditioners using CFC's were a huge problem for the ozone layer, but now HFC's are a problem for the climate.
www.envirolink.org/orgs/edf/sitemap.html

Global Warming is Here
    Naturally, if there are more greenhouse gases in the atmosphere, this greenhouse effect will be more significant and raise the temperature of Earth more than if humans didn't emit as much greenhouse gases.  Peter Tans, a physicist with National Oceanic and Atmospheric Administrations (NOAA) Climate Monitoring and Diagnostics Lab says, There is no doubt that both land and ocean surface temperatures have gone up significantly in the last 100 years or so. (www.abcnew.com/sections/us/global106.html)  This statement supports the trend of global warming, but does not acknowledge the source.  The director of NOAAs Geophysical Fluid Dynamics Lab at Princeton, Jerry Malhan, says, The Earths surface temperature has warmed about one degree Fahrenheit in the last 100 years, and there is no credible hypothesis for this, other than the net effect of greenhouse gases." (www.abcnews.com/sections/us/global106.index.html)  Jerry Malhan offers a quote supporting the theory of global warming and also states that it is directly related to the increase of greenhouse gases.  The planet is heating up and the evidence suggests that human activities are having a significant impact, Jane Lubchenco said. (www.abcnews.com/sections/us/global106/index.html)  Jane was the past President of the American Association for the Advancement of Science, who briefed President Clinton on global warming in July, 1997.  The world's leading authority on global warming, the Intergovernmental Panel on Climate Change (IPCC), is a United Nations sponsored organization made up of 2500 scientists from around the world. They have concluded by consensus that "The balance of evidence suggests a discernible human influence on global climate." They project that global warming will have severe impacts on human health, natural ecosystems, agriculture, and coastal communities. (www.toowarm.org./factsheets/basfact.html)
 This evidence supports the common belief that Global Warming is occurring due to the increased concentration of greenhouse gases in the atmosphere, carbon dioxide, nitrous oxide, methane, and HFCs.
 
Average yearly temperature rise: 1860-1998
www.evirolink.org/orgs/edf/sitemap.html

Effects of Global Warming on Environment
     There are many  environmental problems coming from the increase concentration of greenhouse gases in Earth's atmosphere.  As Jeff Rubin of ABC NEWS reported, Several signs indicate that we've begun changing Earth's climate:  increased water vapor in the atmosphere, glaciers and polar ice caps appear to be melting, floods and droughts are becoming more severe, and sea levels have risen, on average, between 4 and 10 inches since 1990.  (www.abc.com/sections/us/global106.html)  Experts concur, We are already beginning to see this (global warming) taking place - a lot more flooding, a lot more droughts, Jane Lubchenco said. Jerry Malham added, By 2100, we might get a 2 foot sea level rise, but the catch is, levels might continue to rise 2 or 3 feet per century, for 1000 years.(www.abcnews.com/sections/us/global106.html)  These rises in sea level can increase the salinity of freshwater throughout the world, and cause coastal lands to be washed under the ocean.  Warmer water and increased humidity may encourage tropical cyclones, and changing wave patterns could produce more tidal waves and strong beach erosion on the coasts.
 
Flooding form global warming may be already happening.
www.abcnews.com/sections/us/global106.html
Picture of a typhoon from space
www.envirolink.org/orgs/edf/sitemap.html
The effects of droughts on crops
www.abcnews.com/sections/us/global106.html
  
Effects of Global Warming on Society
    Agriculturally, Dr. Sylvan H. Wittwer believes that global warming is good for the human race, because it helps increase food production. "The most determinant factor in agriculture production is climate.  History reveals that for food production, warming is better than cooling."  Dr. Wittwer says that carbon dioxide is an essential nutrient for the production of food, and food is one of the most important things in our lives. As the temperature rises, more farmland will be open towards the poles and the length of the growing season will also lengthen. With all  the people who go hungry each day, Dr. Wittwer believes food production should be one of our main concerns.  Dr. Wittwer is the scientific pioneer who conducted the original studies on atmospheric CO2 enhancement of the production of food crops.(www.comnett.net/~wit/food.html)    Increasing amounts of greenhouse gases in the atmosphere and global warming could also lead to more health concerns.  A statement released from the Intergovernmental Panel on Climate Change (IPCC) said, "Climate change is likely to have wide-ranging and mostly adverse impacts on human health, with significant loss of life."  As temperatures increase towards the poles, similar to farmland, insects and other pests migrate towards Earth's poles. These insects and pests could be allowed to migrate up to 550 Km or 550 miles.  Some insects carry diseases such as malaria and dengue fever.  Thus, an increase in these particular insects and pests closer to the poles results in an increase in these diseases.  This could lead to 50 to 80 million additional cases of Malaria annually, a 10-15% increase.  "Malaria and dengue fever are already beginning to spread pole wards", said Jane Lubchenco, past president of American Association for the advancement of science. (www.epa.gov/oppeoeel/globalwarming/impacts/health/index.html) Physician Paul Epstein, of Harvard's School of Public Health, says "Climate change is already a factor in terms of the distributions of malaria, dengue fever, and cholera." (www.aloha.net~jhanson/page70.htm)
 
    The most obvious health effect is directly from the heat itself.  With an increase in heat waves, there will be more people who will suffer from heatstroke, heart attacks and other ailments aggravated by the heat.  According to the EPA, "In July 1995, a heat wave killed more than 700 people in the Chicago area alone."  (www.epa.gov/oppeoeel/globalwarming/impacts/health/index.html)  If this is happening already from heat, imagine what would occur in the future with global warming.  Hot conditions could also cause smoke particles and noxious gases to linger in the air and accelerate chemical reactions that generate other pollutants. (www.envirolink.org/orgs/edf/sitemap.html) This leads to an increase in risk of respiratory diseases like bronchitis and asthma.
    Global warming causes the oceans to warm and expand, inducing a rise in sea level. Eventually, the rising waters could take away land inhabited by people, forcing them to move.  Dr. Robert Buddemieir, of the Kansas Geological Survey said, "Bangledesh is massively populated, achingly poor, and something like a sixth of the country is going to go away" (www.envirolink.org/orgs/edf/sitemap.html)  Bangladesh cannot afford to build barriers to hold back the sea, so people would have to move inland, increasing the populations density and leading to an increase in hunger and disease. (www.envirolink.org/orgs/edf/sitemap.html)  The Maldive Islands in the Indian Ocean have the same problem  They are a nation of 1190 islands with an average height of about 1.5 meters above sea level.  If the sea level rises, more than 200,000 people will have to abandon their homes. (www.envirolink.org/orgs/edf/sitmap.html)  Warming of the oceans could also promote toxic algae which can lead to cholera.
 
Graph showing history of sea level and extrapolating possible increases in sea level over the next century
The blue line represents the history of sea level.  The yellow line is a high estimate of sea level extrapolated.  The red line a central estimate, and the green line is a low projection.
www.envirolink.org/orgs/edf/sitemap.html
  
The Present ways of Producing Energy
This pie graph shows the breakdown of how the world produces its energy
www.envirolink.org/orgs/edf/sitemap.html
    Fossil fuels, chiefly coal, oil and natural gas, now supply most of the world's energy. Only a small amount comes from renewable sources , which do not release gases that trap heat in the atmosphere. If we could get more of our energy from renewable sources, we could reduce the amount of fossil fuels we burn.  By the year 2050, renewable sources could provide forty percent of the energy needed in the world. Use of renewable energy can help both to slow global warming and to reduce air pollution. (www.doc.mmu.ac.uk/aric/gcc/cell.html#pos6)   These fossil fuels, coal, oil, and natural gas also emit greenhouse gases when burned.  Coal emits high amounts of greenhouse gases, and the world may be supplied with enough of it to last over 100 years.  Oil  emits high amounts of greenhouse gases and also other types of air pollution harmful to the environment. The world's oil supply is also estimated to last over 100 years.  Natural Gas is the lowest of all fossil fuels in greenhouse gas emissions; supplies are projected to last over 100 years. (www.doc.mmu.ac.uk/aric/gcc/cell.html#pos6)

1996 Processes Carbon Dioxide was Produced
Country (region)
OIL
Natural Gas
Coal
World
44.7%
18.4%36.9%
Canada51.8%30%18.2%
United States45%21.3%33.7%
European Union56.2%19%24.8%
China17.4%1.1%81.5%
Japan64.6%9.9%25.5%
  This chart shows what percentage of CO2 comes from Oil, Natural Gas, and Coal. For example, in 1996, 44.7% of the world's CO2 emissions came from the combustion of oil.
http://infoweb.magi.com/~dwalsh/wfsesr.html
This chart shows how much coal different areas of the world have produced and consumed over time
 
 
 Coal accounts for 24% of the worlds energy; Natural gas 18%
www.envirolink.org/orgs/edf/sitemap.html

Solutions for Producing "Cleaner"Energy
 
  Hydro power, currently supplying only six percent of the world's energy, is a renewable energy source. Energy is produced by hydraulic turbines that rotate with the force of rushing water (higher to lower elevation).  It is one of the most clean and cheapest way of producing energy, but it can also change the flow of rivers and increase sediment which kills fish.  It is a large
investment for developing countries. (www.abcnews.com/sections/us/global106)
]
Hydro Power plant on a river
www.envirolink.org/orgs/edf/sitemap.html


   Denmark is currently the world leader in wind power.  By 2030, fifty percent of Denmark's energy could be produced by wind power.  Randall Swisher, executive director of the American WInd Energy Association says, "If this country made an aggressive development push, by 2020 eighteen percent of the country's energy could be supplied by wind power."  (www.abc.com/sections/us/global106.html)  Wind power emits no greenhouse gases, but it takes up large amounts of land.  In order for it to be a reliable source, scientists must develop better power storage techniques.  Another concern of people is noise pollution that the large windmills produce along with the reliability of wind.
 
A field of wind mills
www.envirolink.org/orgs/edf/sitemap.html
 


    Solar power uses photovoltaic cells (PV's) to gather thermal energy directly from the sun and use it to produce electricity.  One community could be supplied by one field of PV's .  Passive solar cells could also be used to heat water, replacing the need for today's hot water heaters.  PV's do not emit any greenhouse gases, but they are very expensive and more development is needed in order for this to be realistic energy source for the future. (www.abcnews.com/sections/us/global106.html)
 
 
A field of PV's gathering sunlight to produce power
www.abcnews.com/sections/us/global106.html

    Nuclear power is strong is Europe with about forty-two percent of their energy produced by fission. Nuclear generation provides about 17% of world electricity, avoiding the emission of up to 2.3 billion tonnes of carbon dioxide annually. France produces 76% and Lithuania produces 85.6% of its energy by nuclear fission.(http://infoweb.magi.com/~dwalsh/wfsesr.html)  In the United States, people are antinuclear because of 3 Mile Island in 1979 and Chernobyl in 1986.  However, many experts say that it is a safe, clean, and reliable source of energy.  Nuclear Fission produces no greenhouse gases, but does produce highly toxic radioactive wastes.
Nuclear power plants have had success in Europe, but not in the United States
www.envirolink.org/orgs/edf/sitemap.html

 Kyoto Protocol
    One of the major conventions concerning global warming resulted in the Kyoto Protocol, held in Kyoto, Japan, between December 1-11, 1997. Delegates from all over the world were present in order to find a universal agreement to reduce greenhouse gas emissions.  The results had most developed nations doing most of the reducing; the United States must cut emissions 7%, Japan 6%, and the European Union 8% below 1990 levels. (www.state.gov/global/oes/fs_kyoto_climate_980115.html)
     The United States proposed a plan to have these levels cut over a five year period between 2008-2013.   The United States also said it will not sign the protocol if other developing/undeveloped countries do not sign it as well, fearing the economy will falter.  The U.S. was successful in emissions trading with other countries who have less emissions. This means that the U.S. or other developed countries can purchase emission permits from other countries who have extra permits.  This stresses the importance of flexibility the U.S. was looking for when it said it cannot lower the emission levels until at least 2008.  Again, the U.S. is trying to look out for it's own economy first.  If a country shall fail in completing its goal, the country will then not be able to receive joint implementation projects.  However, this Protocol is not yet law; it must be ratified by at least 55 countries, accounting for 55% of the world's total greenhouse gas emissions..  It can be signed by countries starting in March of 1998.  The next convention is in November 1998, in Buenos Aires. (www.state.gov/global/oes/fs_kyoto_climate_980115.html)

    If the Kyoto Protocol becomes the law of the land, there are potential economic problems that may lead to a  change in quality of life for many Americans.  By reducing greenhouse gas emissions, people will be more healthy due to better air quality and water quality.  However, there may be a reduction in the rate of economic development because industries will have to adapt and find different ways of producing goods.  People will have to drive smaller, lighter cars, ride bicycles more often, and increase efficiency in many ways.

Greenhouse Gas Overview

Give credit to US EPA
Gases that trap heat in the atmosphere are often called greenhouse gases. This section of the EPA Climate Change Site provides information and data on emissions of greenhouse gases to Earth’s atmosphere, and also the removal of greenhouse gases from the atmosphere. For more information on the science of climate change, please visit EPA's climate change science home page.
Some greenhouse gases such as carbon dioxide occur naturally and are emitted to the atmosphere through natural processes and human activities. Other greenhouse gases (e.g., fluorinated gases) are created and emitted solely through human activities. The principal greenhouse gases that enter the atmosphere because of human activities are:
  • Carbon Dioxide (CO2): Carbon dioxide enters the atmosphere through the burning of fossil fuels (oil, natural gas, and coal), solid waste, trees and wood products, and also as a result of other chemical reactions (e.g., manufacture of cement). Carbon dioxide is also removed from the atmosphere (or “sequestered”) when it is absorbed by plants as part of the biological carbon cycle.
  • Methane (CH4): Methane is emitted during the production and transport of coal, natural gas, and oil. Methane emissions also result from livestock and other agricultural practices and by the decay of organic waste in municipal solid waste landfills.
  • Nitrous Oxide (N2O): Nitrous oxide is emitted during agricultural and industrial activities, as well as during combustion of fossil fuels and solid waste.
  • Fluorinated Gases: Hydrofluorocarbons, perfluorocarbons, and sulfur hexafluoride are synthetic, powerful greenhouse gases that are emitted from a variety of industrial processes. Fluorinated gases are sometimes used as substitutes forozone-depleting substances (i.e., CFCs, HCFCs, and halons). These gases are typically emitted in smaller quantities, but because they are potent greenhouse gases, they are sometimes referred to as High Global Warming Potential gases (“High GWP gases”).
Greenhouse Gas Inventories
A greenhouse gas inventory is an accounting of the amount of greenhouse gases emitted to or removed from the atmosphere over a specific period of time (e.g., one year). A greenhouse gas inventory also provides information on the activities that cause emissions and removals, as well as background on the methods used to make the calculations. Policy makers use greenhouse gas inventories to track emission trends, develop strategies and policies and assess progress. Scientists use greenhouse gas inventories as inputs to atmospheric and economic models.
To track the national trend in emissions and removals since 1990, EPA develops the official U.S. greenhouse gas inventory each year. The national greenhouse gas inventory is submitted to the United Nations in accordance with the Framework Convention on Climate Change Exit EPA Disclaimer.
In addition to the U.S. inventory, greenhouse gas emissions can be tracked at the global, state and local levels as well as by companies and individuals:
The Intergovernmental Panel on Climate Change (IPCC) Exit EPA Disclaimer publishes internationally accepted inventory methodologies that serve as a basis for all greenhouse gas inventories, ensuring that they are comparable and understandable. The 2006 IPCC Guidelines Exit EPA Disclaimer were completed and accepted by the IPCC in May 2006.
Emission Trends & Projections
Estimates of future emissions and removals depend in part on assumptions about changes in underlying human activities. For example, the demand for fossil fuels such as gasoline and coal is expected to increase greatly with the predicted growth of the U.S. and global economies.
The Fourth U.S. Climate Action Report concluded, in assessing current trends, thatcarbon dioxide emissions increased by 20 percent from 1990-2004, while methane and nitrous oxide emissions decreased by 10 percent and 2 percent, respectively. The declines in methane emissions are due to a variety of technological, policy, and agricultural changes, such as increased capture of methane from landfills for energy, reduced emissions from natural gas systems, and declining cattle populations. At least some of the decline in nitrous oxide emissions is due to improved emissions control technologies in cars, trucks, and other mobile sources. (Fourth U.S.Climate Action Report, 2007)
Many, but not all, human sources of greenhouse gas emissions are expected to rise in the future. This growth may be reduced by ongoing efforts to increase the use of newer, cleaner technologies and other measures. Additionally, our everyday choices about such things as commuting, housing, electricity use and recycling can influence the amount of greenhouse gases being emitted.
The United States government prepares projections of emissions and removals of all greenhouse gases. The following links provide more detailed information on projections:
Project Methodologies
EPA has developed several Climate Leaders Offset Project Methodologies that use a standardized approach to determine project eligibility, address additionality, select and set the baseline, identify monitoring options, and quantify reductions.  This approach seeks to ensure that the GHG emission reductions from offset projects meet four key accounting principles—they must be real, additional, permanent, and verifiable.   
To be eligible as offsets, project activities must be surplus to regulation.  Projects are also required to demonstrate additionality by achieving a level of performance with respect to emission reductions and/or removals that is significantly better than business-as-usual.  Business-as-usual is determined from similar, recently undertaken or planned practices, activities or facilities in the same geographic region.  This level of “performance” may be defined as an emissions rate, a technology standard or a practice standard.  Data used in setting the performance standard is primarily collected from publicly available historic data (although planned or projected activities may be used in certain cases as well).  The performance standard approach minimizes the risk of accepting a project that is not additional or rejecting a project that is additional.  A performance standard approach also reduces the complexity, cost, and subjectivity of constructing individual project-specific reviews

Materials Management & Human Health

Give credit to US EPA
The intergenerational dimension of sustainability means that society must be particularly mindful of the long-term threat posed by chemical and biological impacts on the environment. Protecting humans and the environment from toxic chemicals has long been central to EPA's mission and is at the heart of many EPA programs that promote the use of cleaner materials and seek to reduce material waste and chemical contamination. A major priority of the EPA administrator is to enhance and improve the Agency’s chemical management program.
EPA programs provide information on green product design and manufacturing processes that reduce pollution, often at lower costs than conventional techniques. These programs include the development of inherently benign materials and chemicals through green engineering and chemistry, biotechnology and industrial ecology, recovery and reuse of materials, renewable bio-based feedstocks, life cycle assessment, and remediation of polluted areas. Each year, EPA awards the President’s Green Chemistry Challenge Awards in recognition of innovations in cleaner, cheaper, smarter chemistry.
EPA’s E3 Program (Economy, Energy and the Environment) is a coordinated federal and local technical assistance initiative to help manufacturers adapt and thrive in a new business era focused on sustainability. The program provides technical assessments of production processes and training in four key areas: Lean, Clean, Energy, and Greenhouse Gas Emissions.
EPA is also assessing the effects of using nanotechnology to develop safer, more efficient, and sustainable products. 

Energy, Biofuels & Climate Change

Give credit to US EPA



Fossil fuels such as coal, natural gas, and oil provide most of the energy used in the United States but also contribute to climate change and other environmental problems. In September 2009 EPA and the Department of Transportation’s National Highway Safety Administration proposed a national program that would reduce greenhouse gas emissions and improve fuel economy for new cars and trucks sold in the United States.  And in December 2009, EPA’s administrator signed two findings that assessed the possible impact of climate change on human health and declared greenhouse gases a threat to public health and welfare. Activities are underway to begin to inventory and regulate emissions of greenhouse gases.
Adapting to possible effects of climate change will be critical to support environmental protection and economic growth. EPA's global change and climate programs provide timely and useful information and decision support tools to help policy makers and resource managers adapt to a changing climate. EPA’s Global Change Research Program helped support development ofAlaska’s Adaptation Strategy, one of the most comprehensive strategies developed by any state.  This strategy covers public infrastructure, health and culture, natural systems, and economic activities.  Alaska has also published reports om its mitigation strategy and research needs .
Efforts are underway in the Unites States to promote renewable energy sources and the sustainable production of biofuels.  The sustainability of the biofuels supply chain from feedstock production to end use will determine the degree to which biofuels reach their full environmental potential and reduce reliance on petroleum. EPA is finalizing a new Renewable Fuel Standard for 2010 and beyond.  In 2010, EPA will launch a new research program to assess possible environmental and health impacts resulting from expanding use of biofuels derived from different feedstocks and will prepare a report mandated by Congress on current and potential future impacts of biofuels on the environment.

Water & Ecosystem Services

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EPA programs and resources are helping states and communities to manage, protect, and restore water and ecosystems through sustainable management of natural resources. EPA also provides information that assists the agricultural sector to achieve regulatory compliance through sustainable practices.
EPA’s Office of Water is focusing attention on sustainable infrastructurefor water and waste water and has prepared a report on Sustaining Our Nation’s Water Infrastructure.
EPA’s ecosystem research helps communities develop tools to support sustainability and good stewardship.
Ecosystem services are the many life-sustaining benefits we receive from nature--clean air and water, fertile soil for crop production, pollination, and flood control. These ecosystem services are important to our health and well-being, yet they are limited and often taken for granted as being free.

Urban Sustainability & the Built Environment

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Nearly 80 percent of U.S. residents were living in urban environments in 2000 and that proportion is continuing to grow, according to state and national data on rural and urban population available from the U.S. Census Bureau.
Buildings account for more than 40 percent of total energy consumption in the United States. It follows that how and where urban development occurs can affect ecosystem quality and services, habitat protection, water resources, energy consumption, and indoor and outdoor air quality. A National Science and Technology Council (NSTC) report on net-zero, high-performance green buildings sets out a broad agenda for technological research and development to reduce use of natural resources and improve indoor environments while reducing emissions from buildings of greenhouse gases and other harmful pollutants.
EPA programs and resources are helping states and local communities to promote urban sustainability by supporting smart growthgreen communities   and green buildings. Also, check out EPA’s new green homes Web site offers information and practical advice relevant to residential uses. 

Sustainability

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The Sustainability Program of EPA's Office of Research and Development maintains this Web site to provide one-stop access to EPA and related programs and the latest research and activities related to the four topic areas listed specified under the four photos below:
photo - Boston skylinephoto - arial view of riverphoto - windmillsphoto - worker with chemicals