Perhaps South Dakota will repeal the law of gravity, next?

[Torvald Von Mansee]

http://www.scientificblogging.com/ch...d_laws_science

[Stealth Hunter]

Omg...

[August]

Well care to point out what is actually incorrect about any of these statements?

(1) That global warming is a scientific theory rather than a proven fact;
(2) That there are a variety of climatological, meteorological, astrological, thermological, cosmological, and ecological dynamics that can effect world weather phenomena and that the significance and interrelativity of these factors is largely speculative; and
(3) That the debate on global warming has subsumed political and philosophical viewpoints which have complicated and prejudiced the scientific investigation of global warming phenomena

[NeonSamurai]

Originally Posted by August

Well care to point out what is actually incorrect about any of these statements?

(1) Well its all theory, in theory at least. If you want to get really philosophical about it, you can make the valid statement that there is no proven fact at all, we can't even really prove we exist, or that anything we "sense" does.

(2) Its a lot more then simple speculation, there is considerable evidence in support of the theories relating to this topic. This isn't some theory a guy came up with one day on the back balcony having a beer, based on sheer speculation.

(3) I think it has far more prejudiced the greater populace as to its debate on the topic rather than the scientific community itself (notice how the political sides have lined up on the issue?). The scientific community at least has some training in identifying their own biases and trying to control for them. Plus of course the whole thing on the scientific method which is designed to reduce bias as much as possible.


Anyhow sounds like that group has their own agenda, probably pandering to their constituents, or business pressures.

[razark]

Originally Posted by August

Well care to point out what is actually incorrect about any of these statements?

The definition of "theory" in a scientific discussion, for one.

Also, what are the "astrological... dynamics that can effect world weather phenomena"? What does astrology have to do with anything?

That shows that the people passing the laws aren't exactly the best people to deal with the subject. Edit: This last part is a problem with a lot of laws. Politicians are great at PR and getting elected. They're not really experts in anything else. But they make the laws that affect everything.

[Stealth Hunter]

Originally Posted by The Article

(1) That global warming is a scientific theory rather than a proven fact;

Perhaps they should refresh their memories of junior high on what a scientific theory is exactly... a well-tested theoretical concept confirmed by present facts and evidence gathered by researchers that explains a wide range of observations for whatever specific field of study, or fields. (-The National Science Foundation)

Originally Posted by The Article

(2) That there are a variety of climatological, meteorological, astrological, thermological, cosmological, and ecological dynamics that can effect world weather phenomena and that the significance and interrelativity of these factors is largely speculative;

Pretty much correct, except for the "largely speculative" part- which, aside from being erroneous (you don't speculate when it comes to the sciences...), they also fail to define this usage of terminology.

Originally Posted by The Article

(3) That the debate on global warming has subsumed political and philosophical viewpoints which have complicated and prejudiced the scientific investigation of global warming phenomena

First half, well that goes without say. This happens with anything when it comes to the public's views. Very rarely, though, does something this large become that political (the majority of the scientific community is in consensus that global warming is at least partially caused by humans; source: http://en.wikipedia.org/wiki/Scienti...fic_literature) when it comes to the actual scientists who are doing the investigations and research/studies. It's never been proven in this instance that they've been influenced, anyway. The "Climate-Gate" scientists who were supposedly hiding data and discussing it in emails were cleared of all charges and found innocent by the House of Commons' Science and Technology Committee.

http://www.publications.parliament.u...h/387/387i.pdf

[SteamWake]

There is no gravity... the earth sucks

[NeonSamurai]

Originally Posted by Stealth Hunter

The "Climate-Gate" scientists who were supposedly hiding data and discussing it in emails were cleared of all charges and found innocent by the House of Commons' Science and Technology Committee.

http://www.publications.parliament.u...h/387/387i.pdf

Oh good, was wondering when that was going to finish. You should post that to the global warming thread

[August]

Originally Posted by NeonSamurai

(1) Well its all theory, in theory at least. If you want to get really philosophical about it, you can make the valid statement that there is no proven fact at all, we can't even really prove we exist, or that anything we "sense" does.

But some people act like it is indeed proven fact. Skybird does it all the time.

(2) Its a lot more then simple speculation, there is considerable evidence in support of the theories relating to this topic. This isn't some theory a guy came up with one day on the back balcony having a beer, based on sheer speculation.

They said "largely" speculation. YOU are the one changing that to "sheer" speculation and "simple" speculation.

(3) I think it has far more prejudiced the greater populace as to its debate on the topic rather than the scientific community itself (notice how the political sides have lined up on the issue?). The scientific community at least has some training in identifying their own biases and trying to control for them. Plus of course the whole thing on the scientific method which is designed to reduce bias as much as possible.

Well I agree and you'd think the scientific community would have learnt to stay out of politics by now but I guess they have to pander to the alarmists in order to get their funding.

[NeonSamurai]

Originally Posted by August

But some people act like it is indeed proven fact. Skybird does it all the time.

They said "largely" speculation. YOU are the one changing that to "sheer" speculation and "simple" speculation.

Well I agree and you'd think the scientific community would have learnt to stay out of politics by now but I guess they have to pander to the alarmists in order to get their funding.

The main thrust of my 2nd reply was that it is evidence based, not speculative in nature. They are making it sound like the science is pure speculation, which is false.

The scientific community is largely out of the picture, not really pandering to anyone. Most governmental funding comes regardless of the direction of results, they just want an accurate picture. Its these other people that are taking the science and running with it to further their own ends. Just like those on the other side are doing the same thing too. I guess this is why I like scientific discourse most, as it is by in large politics free. Everything else is poisoned by political weighting.

[August]

Originally Posted by NeonSamurai

Everything else is poisoned by political weighting.

I think that's the main point the SD legislature is trying to address here.

[tater]

Sadly, many AGW skeptics are also very creationist in their thinking (or are actually creationists). It gives those of us who are NOT a bad rep.

I'd call AGW a hypothesis, not a theory, since their models don't nearly explain the observations well enough to meet the standard required for theory. Not really reproducible, either, since they publish neither their data, nor their models.

If they'd keep "global warming" out of public policy, no one would bother with it and they could stop politicizing it in any direction and just do the science.

[Aramike]

Oh, this is rich ... somehow libs have found fault with a resolution:

...Calling for balanced teaching of global warming in the public schools of South Dakota.

which essentially simply requires that the science be taught without being presented as rock-solid conclusions.

I wonder who to trust more - the aforementioned lefties or the people who flat-out state their agendas.

[Bubblehead1980]

Looks like the bill is just saying that a balanced teaching of global warming must be taught.Let's face it guys, global warming is not a FACT, it is a theory and one that I and many people find unlikely.Now, I will not deny that man's pollution has an effect on the earth in some ways and thus we need to find ways to live and not pollute the earth so much(not things like cap and trade that will hurt us), but we do not have the impact to the extent Al Gore and company argue.Although I disagree with global warming theory, both sides should be taught as THEORY and students can make up their own minds.

I live in the Florida Panhandle(Pensacola) and the winters here do get cold but this past winter was the coldest thus far in my life.I looked up some info:

The average winter reading this season in Pensacola has been 48.4 degrees, which is 5.3 degrees below normal. Here are the coldest winters on record from the National Weather Service for Pensacola.

1.) 47.4 average temp in 1977
2.) 47.5 average temp in 1978
3.) 47.6 average temp in 1964
4.) 48.4 average temp in 2010

48.4 may have been the AVERAGE temp but there were many nights, including 11 days straight in January when the temp went below freezing, in Florida(!) Talked to some friends in south florida and was told it was cooler down there as well.Put this in with the record snow storms in the US and all.Oh yea, the climate change conference that was in copenhagen(i think) they had a record blizzard during or right before the big meeting right? Global Warming my ass OH wait, I think someone actually said that global warming was causing us to have harsher winters LOL

On a more partisan note: The envrionazis are a force in the Dem party thus their candidates have catered to them and pushed this crap as if it's real scientific fact and not a theory.Kind of a good scheme except facts and rational thinking just don't match up with it

[Stealth Hunter]

Originally Posted by Bubblehead1980

Looks like the bill is just saying that a balanced teaching of global warming must be taught.Let's face it guys, global warming is not a FACT, it is a theory and one that I and many people find unlikely.Now, I will not deny that man's pollution has an effect on the earth in some ways and thus we need to find ways to live and not pollute the earth so much(not things like cap and trade that will hurt us), but we do not have the impact to the extent Al Gore and company argue.Although I disagree with global warming theory, both sides should be taught as THEORY and students can make up their own minds.

I live in the Florida Panhandle(Pensacola) and the winters here do get cold but this past winter was the coldest thus far in my life.I looked up some info:

The average winter reading this season in Pensacola has been 48.4 degrees, which is 5.3 degrees below normal. Here are the coldest winters on record from the National Weather Service for Pensacola.

1.) 47.4 average temp in 1977
2.) 47.5 average temp in 1978
3.) 47.6 average temp in 1964
4.) 48.4 average temp in 2010

48.4 may have been the AVERAGE temp but there were many nights, including 11 days straight in January when the temp went below freezing, in Florida(!) Talked to some friends in south florida and was told it was cooler down there as well.Put this in with the record snow storms in the US and all.Oh yea, the climate change conference that was in copenhagen(i think) they had a record blizzard during or right before the big meeting right? Global Warming my ass OH wait, I think someone actually said that global warming was causing us to have harsher winters LOL

On a more partisan note: The envrionazis are a force in the Dem party thus their candidates have catered to them and pushed this crap as if it's real scientific fact and not a theory.Kind of a good scheme except facts and rational thinking just don't match up with it

Oh boy... where to begin. I guess with having us ask ourselves just one question: is the increase in CO2 man-made? And I shall address it in an at least moderately well organized format.

Simple Accounting (second order evidence)

The first thing one must look at for this is simple accounting. We know how much carbon (as in fossil fuels) we've burned since the beginning of the Second Industrial Revolution and birth of the Industrial Age. The total amount comes to around twice as much as the increase in atmospheric CO2 (we'll get into where the last part went - when we get further on in this debate; see the first three citations for this particular segment's sources of information).

Carbon Isotopes (first order evidence)

The second thing which scientists and we can base our conclusions upon are measurements of carbon (C-12) and its isotopes (C-14 and C-13) in the atmosphere (referred to as the Suess Effect; cited in the fourth and fifth sources listed).

Carbon-14 is created in the upper troposphere by high-energy reactions created by cosmic rays. It's is radioactive and has a half-life of 5730±40 years. Because it is radioactive, it undergoes radioactive decay. As such, it's frequently used in dating objects just around 100,000-years-old (radiometric dating can trace back billions of years, on a related note). Oil, coal, and other fossil fuel materials have no carbon-14 content (as it's decayed away over the 65 million years or so that the oil began formulating, around the time of the mass extinctions of the dinosaurs and 90% of all life on the surface of Earth). So, when we burn the fossil fuel materials, they release carbon with no C14 content. This means that the amount of C14 in the atmosphere should fall, and indeed it does.

Carbon-13 has the strange characteristic that causes plants to not particularly "like it", so when plants use CO2 in carrying out their metabolic photosynthesis pathway, they avoid using the C13. This means that plant material is consisting almost completely of carbon-12, and for the same reason, oil, coal, and other fossil fuel materials contain almost no C13. So when we burn it we'll see the same effect as for C14: The relative abundance of (C12,C13,C14) changes.

The latter two (C13,C14) and their relative abundance work as a fingerprint as to where the carbon is coming from. This means we can trace their sources for each cubic foot of the gases we capture and study.

Plant material has low levels of C13 but normal levels of C12 and C14.
CO2 produced from dissolution in the oceans has normal levels of C12 and C13 (normal levels of C14, but could be low if the CO2 came from the bottom, for whatever reason).

Fossil fuel materials have low levels of C13 and C14 (being almost pure C12).

So when the atmospheric level of C13 and C14 falls (as measured and documented by practically all climate change research institutes and organizations) in proportion to C12, then we can see that it comes from the burning of fossil fuels. Consequently, we know it was not produced naturally, but from human beings burning the fuels for whatever reason (cars, industrial complexes, power plants, etc.).

Paleo-data (first order evidence)

This line of evidence is primarily inferred during the last stable geological period (around 20 million years ago). CO2 in the atmosphere has varied between 180ppm (the coldest parts of a glacier) and 300ppm (the warmest part of the interiors of the glaciers). We know this from several paleo sources, particularly ones relating to ice core samples that have been taken from all around the globe. All results gathered have shown virtually the same thing: a general trend of warming followed by a violent period after the Second Industrial Revolution and the birth of the Industrial Age. During the last 150 years (or since we started to burn fossil fuels like coal in factories, steamships, and the like), the atmospheric content of CO2 has risen by 35.7% from 280ppm (has been reasonably stable here for the last 20.000 years) to currently around 380ppm (see the sixth and seventh sources listed below). That's a large increase, not at all like the natural trends found before.

Sinks and Sources (second order evidence)

This line of evidence is based upon tallying the various sources, and the various sinks of CO2; what is calculated is the net sink or net sources. The ocean, for instance is emitting CO2 (the algae in it is anyway), but is also sinking CO2 (from other types of algae, too). By subtracting these fluctuations, we can see how much the oceanic contribution to the carbon budget is (eighth source listed).

When calculating this we can see that the annual contribution to the atmosphere is around 2ppm (or 4.26 Gt CO2), and we can also see that the only source where this can come from is from human (antropogenic) sources. Since nature as a whole is acting as a sink, save for a few exceptions.

Oxygen content (first order evidence)

The last one is rather simple. When carbon is burned, it oxidizes. That means that it uses 1 oxygen molecule. So for each new carbon atom released, 2 oxygen atoms are used. This can be measured since in each 100 atoms of fossil fuel carbon burned, about 140 molecules of O2 are consumed (ninth source listed)

Addendum here: the reason that this line of evidence is important is that if the CO2 had come from the oceans as many global warming/climate change deniers claim, the oxygen level would not fall as the CO2 is released with oxygen molecules from the oceans as well (tenth source listed).

It would have been theoretically possible for the CO2 to come from the very bottom of the oceans (for example, large outgassings beyond what Henry's law could counteract and thus elude us by still making the surface waters acidic), which means that it could have been stored away for thousands of years, exhibiting the same C14 depletion as fossil fuels, so that the oxygen level falls proportionally with CO2 increase. This means that the CO2 couldn't originate in the oceans, but if this were true, then this wouldn't have the C13 signature seen though.

The same can be said for volcanoes, as they also release it as CO2 (without oxygen from the atmosphere). This happens by metamorphism of basic elements and substances. For instance, carbonates reacting with quartz, the chemistry being represented as: CaCO3 + SiO2 = CO2 + CaSiO3. The calcium silicates (CaSiO3) come back out as lava, adding to continental crust, and the CO2 comes out of the volcanoes as an explosive gas- which leaves very few atmospheric traces despite claims made by deniers and their "research".

---------------------------------------------------------------------------------------------

Sources:


CDIAC CO2 emissions http://cdiac.ornl.gov/ftp/ndp030/global.1751_2005.ems

Mauna Loa atmospheric CO2 http://cdiac.ornl.gov/ftp/trends/co2/maunaloa.co2

1 ppm by volume of atmosphere CO2 = 2.13 Gt C http://cdiac.ornl.gov/pns/convert.html

Tans et al(1979) "Natural atmospheric 14C variation and the Suess effect" Nature 280, 826 - 828; doi:10.1038/280826a0 http://www.nature.com/nature/journal.../280826a0.html

Battle et al(2000) "Global Carbon Sinks and Their Variability Inferred from Atmospheric O2 and d13C" Science 31 March 2000: Vol. 287. no. 5462, pp. 2467 - 2470 DOI: 10.1126/science.287.5462.2467 http://www.sciencemag.org/cgi/conten...;287/5462/2467

http://cdiac.ornl.gov/trends/co2/vostok.html

http://cdiac.ornl.gov/trends/co2/graphics/lawdome.gif

http://www.whrc.org/carbon/index.htm

Bender et al(2005) "Atmospheric O2/N2 changes, 1993–2002: Implications for the partitioning of fossil fuel CO2 sequestration" Global Biochemical Cycles, vol. 19, gb4017, doi:10.1029/2004GB002410 http://www.agu.org/pubs/crossref/200...GB002410.shtml

Wallace S. Broecker "Et tu, O2" http://www.columbia.edu/cu/21stC/issue-2.1/broecker.htm


The greenhouse effect itself is what keeps the earth warm and habitable for us. If we didn't have it, Earth’s surface would be about 60*Fahrenheit on average. Since the average temperature of Earth is about 45*F, the natural greenhouse effect is clearly a good thing, as are the gases in limited quantity. But the enhanced greenhouse effect means even more of energy given off by the sun is trapped by having too many of the gases in our atmosphere, the result of course being global temperatures rising.

By pumping man-made greenhouse gases into the atmosphere, humans are altering the process by which naturally occurring greenhouse gases trap the sun's energy before it can be released back into space. The main gases are as followed:

• Carbon Dioxide (CO2; unnaturally produced/exacerbated by fossil fuel combustion, land use conversion (destroying trees and other plants which are responsible for recycling it and emitting oxygen as a byproduct, and basic cement production)
• Methane (CH4; fossil fuels, farms, waste dumps)
• Nitrous Oxide (N20; fertilizer, industrial production, combustion)
• Chlorofluorocarbon-12 (CCL2F2; liquid coolants and foams)
• Hydrochlorofluorocarbon-22 (HCCL2F2; refrigerants)
• Perfluoroethane (C2F6; smelting of metals, semiconductor manufacturing)
• Sulfur Hexafluoride (SF6; dielectric fluids)

All chlorofluorocarbons listed are damaging to ozone, the greenhouse gas (albeit, a harmless one) that is there to protect us from the sun's great amount of energy and UV-rays.


Today, tropospheric composition of these gases is as follows (in parts per billion with the numbers from 1750 included for comparison):

• Carbon Dioxide - 377,700 (280,000)
• Methane - 1,847 (635)
• Nitrous Oxide - 319 (260)
• CFC-12 - .545 (0)
• HCFC-22 - .174 (0)
• Perfluoroethane - .03 (0)
• Sulfur Hexafluoride - .00522 (0)

Source of graphical information:

Blasing, T.J. ad K. Smith 2006. "Recent Greenhouse Gas Concentrations." In Trends: A Compendium of Data on Global Change. http://cdiac.ornl.gov/pns/current_ghg.html Carbon Dioxide Information Analysis Cetner, Oak Ridge National Laboratory, US Department of Energy, Oak Ridge, TN, USA.

Global CO2 flows, carbon reservoirs, and changes in the reservoirs can best be displayed via a statistical figure representative:



The tan colored pool is decreasing in size, but the blue colored pools are increasing. Intensity of the blue color indicates the magnitude of stock change. The numbers in orange indicate the total amount of carbon in the reservoir discovered by NCAR, green ones the average annual change in the amount of carbon in the reservoir. Also note that a gigaton (as the graph is displayed in; Gt.) are as follows: 1 Gt = 109 metric tons

Source of graph: Bolin et al. in NCAR, 2007a; Houghton.

As shown in the graph, the annual average human-induced flows of CO2 - 6.3 gigatons from fossil fuel combustion and 1.6 Gt from deforestation in the from the late 1990s/early 2000s- are a small fraction of total CO2 flows. However, these flows are resulting in increased carbon in the ocean and atmospheric reservoirs on Earth.

Anthropogenic emissions of CH4 and N2O comprise a much larger share of total emissions of these gases than is the case for CO2. Approximately 70% of the 550 million metric tons of CH4 emitted annually and about half of the 14 MMT of N2O emitted annually are due to human activities, concentrated over large industrial nations- chiefly being India and China (source: also Bolin et al. in NCAR, 2007a).

It should be noted that water vapor also acts as a significant contributor to the greenhouse effect (which, for the record, is not at all like how a literal greenhouse works). This is a result of the natural cycle of water.

One of the most important bits of evidence touched upon are global surface temperature trends. The global average surface temperature fluctuates over time, but in recent decades it has increased dramatically. From 1920 to the present, Earth’s average surface temperature has increased by 1.4*F. According to the National Academy of Sciences, this change is the largest global temperature rise in at least the last 2,000 years and may steal the record from the last 5,000 years. The sharpest rise occurred between 1975 and 2005, when temperatures rose steadily by about 1*F on average.

The recent increase in concentration of carbon dioxide in the atmosphere is the result of human activities, as we discussed earlier- mainly the burning of fossil fuels. As the concentration of CO2 in the atmosphere has increased, so has the average surface temperature (to reiterate). The relationship between atmospheric CO2 concentration and surface temperature is shown here for the past 150 years.





Source for CO2 concentration data: Keeling, C.D. and T.P. Whorf, 2005. Atmospheric CO2 records from sites in the SIO air sampling network. In Trends: A Compendium of Data on Global Change. Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, U.S. DOE, Oak Ridge, Tenn., U.S.A.

Source for temperature data: Brohan, P., I. Haris, S.F.B. Tett, P.D. Jones, and J.J. Kennedy, 2006. Uncertainty estimates in regional and global observed temperature changes: a new dataset from 1850. Journal of Geophysical Research, p. 111, 2003.

Over the last 400,000 years.



This data was also collected by C.D. Keeling and T.P. Whorf, published on pages 121-126 of issue #398 of Nature magazine in 2000.

The graph below this section of paragraphs compares measurements of the Earth’s past temperature variations (shown by the black line) with simulations of past temperature variations (shown by the red and blue lines) in order to determine whether the major changes in temperature were caused by natural or human-caused factors.

The black line shows observed surface temperature variations from the average. The blue and red lines show computer model results when past temperatures are simulated including different drivers of the climate system. Natural drivers include solar radiation and volcanic emissions, while anthropogenic (man-made) drivers include man-made greenhouse gases and sulfate aerosols. The blue line shows variation when natural drivers are included in the calculations, while the red line shows variation when both natural and anthropogenic drivers are included.

This graph shows that the combination of natural and anthropogenic drivers (the red line) provides a better match to the observed temperatures (black line) than only natural drivers (the blue line).

Natural drivers alone can explain much of the temperature change in the first half of the century, as demonstrated by the similarity between the black and blue lines during that time period. As can be seen with the close match between the red and black lines, human-produced drivers strongly dominated the temperature change in the latter part of the 20th century.



The source: Meehl, G.A., W.M. Washington, C.M. Ammann, J.M. Arblaster, T.M.L. Wigley, and C. Tebaldi, 2004. Of Models and Men. Journal Collective of Scientific Minds, p. 44, found in the January 2005 edition.

The graph below shows the heat content of the ocean measured at three depths: from 0-300 meters (red line), from 0-700 meters (blue line), and from 0-3000 meters (gray line). Each line on the graph corresponds to measurements taken at one of these three depths and shows a gradual increase in heat content over time. Warming of the oceans has many consequences, including sea level rise, coral bleaching, loss of sea ice, intensification of hurricanes, and higher coastal storm surges. Taken together with the graph below, this shows that increased temperatures have been observed at Earth’s surface and in the oceans.



Source: Levitus, S., J. Antonov, and T. Boyer, 2005. Journal of Geophysical Research, p. 66, 2005.

One of the projected impacts of climate change is an increase in sea level. This figure shows the results of satellite measurements of the change in average global sea level in recent times. The slope of the graph suggests that the change in sea level is accelerating, which is expected as a result of global warming.



Source: Cazenave, A. and R.S. Nerem, 2004. Present-day sea level change: Observations, Causes, and Conclusions. Rev. Geophys., p. 42.

This figure compares the extent of the summer arctic sea ice in 1979 with the extent of the sea ice in summer 2005. Since 1979, more than 20% of the Polar Ice Caps have melted away in response to increased surface air and ocean temperatures. Information and graphical representation from NASA and the Natural Resources Defense Council.

The figure below demonstrates the trend in arctic sea ice extent, as measured in September, the annual summer minimum for sea ice extent, for each reporting year. Starts in 1979, going in intervals of five years until the 2004 mark, and ends in 2006 (the quality is also downgraded, for some reason; probably the pure-white background it had in the magazine- from the National Snow & Ice Data Center).



This figure also shows the number of named tropical storms in the North Atlantic, per year, smoothed out over a decade long running average to minimize the clutter of data in year-to-year variation. Since 1996, tropical storm frequency has exceeded by 40% the old historic maximum of the mid-1950s, previously considered extreme. Recent peer-reviewed studies suggest a link between higher sea surface temperature and storm frequency. Extreme weather events are a projected impact of global climate change.



In the year 2004, the United States emitted over seven billion metric tons of greenhouse gases (CO2E). Carbon dioxide accounted for the largest percentage of greenhouse gases (83%), followed by methane (9%), nitrous oxide (5%), and the high global warming potential gases (2%).

(sources are all listed beneath the images; if they're too blurry, I'll write them out for anyone who asks)



Greenhouse gases are emitted by all sectors of the economy, including industry (30% of total), transportation (28%), commercial (17%), residential (17%), and agriculture (8%). In this figure, greenhouse gases from electricity generation have been allocated to the end-use sector. (from the EPA's website)

This figure shows the trends in US carbon dioxide emissions between 1990 and 2004. The data indicate that carbon dioxide emissions increased 15.8% between 1990 and 2004.



This figure shows the emissions of carbon dioxide from the burning of fossil fuels in the generation of electric power. The three electricity-generating fuels shown here are coal, natural gas, and petroleum.



This figure shows trends in emissions of carbon dioxide from the burning of oil to produce energy for the following five sectors: transportation, industry, electric power, residential, and commercial.



The transportation sector is the second largest contributor of greenhosue gas emissions (mainly in the form of carbon dioxide) in the United States (see the second figure in this post). This figure shows the trends in aggregate and per capita vehicle miles traveled by Americans per year.



Greenhouse gas emissions, largely CO2 from the combustion of fossil fuels, have risen dramatically since the start of the industrial revolution. Globally, energy-related CO2 emissions have risen approximately 145-fold since 1850 - from 200 million tons to 29 billion tons a year.



Most of the world's greenhouse gas emissions come from a relatively small number of countries. The United States, China, and the European Union (EU-25) together accounted for about 50% of global emissions in 2004. The eight largest emitters- the United States, China, the European Union, Russia, India, Japan, Germany and Brazil- accounted for more than 70% of global emissions.



Greenhouse gases remain in the atmosphere and contribute to global warming long after they are emitted (in most cases, for a century or more), so cumulative emissions are an important measure of a country's contribution to climate change. From 1850 to 2000, the United States and the European Union were responsible for about 60% of energy-related CO2 emissions, while China contributed 7% and India 2%.



Globally, the primary sources of greenhouse gas emissions are the energy supply sector (26%), industry (19%) and forestry (17%). Agriculture and transportation account for 14% and 13% of total emissions, respectively.



CO2 accounts for about 80% of total greenhouse gas emissions- 57% from fossil fuel use and 20% from deforestation and other activities. Methane, primarily from agriculture, is the next largest category of emissions (14%). Note that different gases have different potentials. All figures here are expressed in CO2-equivalents.



Anybody else interested might also want to check these sources:
---------------------------------------------------------------------------------------------

den Elzen, M & M Meinshausen. "Multi-gas emission pathways for meeting the EU 2°C climate target," Avoiding Dangerous Climate Change. Cambridge University Press. 2005.

Intergovernmental Panel on Climate Change, Climate Change 2001: Synthesis Report, Cambridge University Press. 2001.

Intergovernmental Panel on Climate Change, Climate Change 2001: Synthesis Report: Summary for Policy Makers.

Joint Statement of Science Academies: Global Response to Climate Change, 2005

Michaels, Patrick J. "Non-Linear Climate Change," World Climate Report. 9 Aug 2004.

Michaels, Patrick J. "Observations, Not Models," World Climate Report. 14 April 2004.

Michaels, Patrick J. "Hot Tip: Post Misses Point," World Climate Report. 31 Jan 2006.

National Acadamies of Science. "Climate Change Science: An Analysis of Some Key Questions," The National Academies Press. 2001.

Pielke, Jr., R. A., C. Landsea, M. Mayfield, J. Laver and R. Pasch. "Hurricanes and Global Warming," Bulletin of the American Meteorological Society. Nov 2005.