Global warming

[lucaspa]

Today at 09:21 PM Hank said this in Post #17

One more question, percentage wise how accurate is that data?

I still can't find actual literature where the data is collected from and how.

Try some of these articles and the articles referenced by them:

1:  McCulloch A.
Chloroform in the environment: occurrence, sources, sinks and effects.
Chemosphere. 2003 Mar;50(10):1291-308.
PMID: 12586161 [PubMed - in process]

2:  Harnisch J, de Jager D, Gale J, Stobbel O.
Halogenated compounds and climate change: future emission levels and reduction costs.
Environ Sci Pollut Res Int. 2002;9(6):369-74.
PMID: 12515342 [PubMed - indexed for MEDLINE]

3:  Root TL, Price JT, Hall KR, Schneider SH, Rosenzweig C, Pounds JA.
Fingerprints of global warming on wild animals and plants.
Nature. 2003 Jan 2;421(6918):57-60.
PMID: 12511952 [PubMed - indexed for MEDLINE]

4:  Menon S, Hansen J, Nazarenko L, Luo Y.
Climate effects of black carbon aerosols in China and India.
Science. 2002 Sep 27;297(5590):2250-3.
PMID: 12351786 [PubMed - as supplied by publisher]

5:  Pacca S, Horvath A.
Greenhouse gas emissions from building and operating electric power plants in
the Upper Colorado River Basin.
Environ Sci Technol. 2002 Jul 15;36(14):3194-200.
PMID: 12141503 [PubMed - indexed for MEDLINE]

6:  Beerling D.
CO2 and the end-Triassic mass extinction.
Nature. 2002 Jan 24;415(6870):386-7; author reply 388.
PMID: 11807542 [PubMed - indexed for MEDLINE]

7:  Schultz PA, Kasting JF.
Optimal reductions in CO2 emissions.
Energy Policy. 1997 Apr;25(5):491-500.
PMID: 11542949 [PubMed - indexed for MEDLINE]

8:  O'Neill BC, Gaffin SR, Tubiello FN, Oppenheimer M.
Reservoir timescales for anthropogenic CO2 in the atmosphere
Tellus B. 1994 Nov;46B(5):378-89.
PMID: 11541520 [PubMed - indexed for MEDLINE]

9:  Cox PM, Betts RA, Jones CD, Spall SA, Totterdell IJ.
Acceleration of global warming due to carbon-cycle feedbacks in a coupled
climate model.
Nature. 2000 Nov 9;408(6809):184-7.
PMID: 11089968 [PubMed - as supplied by publisher]

10:  Robertson GP, Paul EA, Harwood RR.
Greenhouse gases in intensive agriculture: contributions of individual gases to
the radiative forcing of the atmosphere
Science. 2000 Sep 15;289(5486):1922-5.
PMID: 10988070 [PubMed - as supplied by publisher]

11:  Hansen J, Sato M, Ruedy R, Lacis A, Oinas V.
Global warming in the twenty-first century: an alternative scenario.
Proc Natl Acad Sci U S A. 2000 Aug 29;97(18):9875-80.
PMID: 10944197 [PubMed - indexed for MEDLINE]

12:  Newcomb TM Jr.
Assessing data for precursors of CO2 and methane in King County, Washington,
1990.
Eval Rev. 1998 Dec;22(6):792-815.
PMID: 10345199 [PubMed - indexed for MEDLINE]

13:  Piver WT.
Global atmospheric changes.
Environ Health Perspect. 1991 Dec;96:131-7. Review.

 

[lucaspa]

Today at 09:21 PM Hank said this in Post #17

I still can't find actual literature where the data is collected from and how.

I think it was Notto that already gave you this site. Why don't you look at it or even better, do a www.google.com search under "global warming"? You'll find the data.

http://yosemite.epa.gov/oar/globalwarming.nsf/content/index.html

 

[lucaspa]

Hank, also try http://yosemite.epa.gov/oar/globalwarming.nsf/UniqueKeyLookup/SHSU5BUM9T/$File/ghg_gwp.pdf

 

[Morat]

A bit more on compression melting, and household fun. Take a cube of ice.

Stick it in the freezer. Now, take a weight, and hang it from the ice by a length of wire. (So that your weight is supported by the wire running around the ice). Leave it alone.

Come back later, and you'll find that the ice has melted under the wire and refrozen over it. Compression melting caused by the weight hung from the wire.

 

[Hank]

Yesterday at 10:24 PM lucaspa said this in Post #20

Hank, I didn't say "deflect" the radiation, I said absorb the radiation.  If you shine light on any chemical, you find that the bonds between the atoms absorb some wavelengths of light.  The atoms also absorb some wavelengths.  Microwaves work by having the H-O bonds of water absorb the light waves of the microwave which causes the molecules to move faster which means that the food becomes hotter.

So yes, shining a heat lamp in a warehouse will cause the the solid objects to warm up because there are so many photons of infrared light that there is not enough CO2 to absorb all of them and a lot get through to the solid objects. But the temperature of the air also increases a bit.

Now, remember what I said: the ground radiates the infrared light so that it would leave the earth, thus cooling it. However, the C=O bonds in CO2 absorb some of that light instead, keeping it from escaping.  Thus, the earth is warmer because it can't get rid of the heat. 

Thanks.

This I too understand. Yet gas is gas. As you can see at the schedule, where N and O is to be read as O2 and N2 the heat absorption ability is nearly the same to that of CO2.

http://pump.net/thebasics/physpropgases.htm

As for the micro-wave, here we deal with water. Water and also the vapor in the air does absorb a great deal of heat. It's classified by specific heat, meaning how much energy is required to raise the temperature of a given medium. And vapor stand out. As for the Micro-wave they are tuned to the frequency of the water molecule. The difference here is that any other radiation would heat that water also, but the micro-wave is calibrated to the frequency of water, and thus expedites the heating process. The main difference between H2O and CO2 is that the H2O molecules are polar covalent bonds and do react with radiation; and calibrating the polar bond is childsplay. I have no such luck with CO2.

I will go through your other reading suggestions and hope to find something there.  

 

[notto]

Today at 08:47 PM Hank said this in Post #25 (http://www.christianforums.com/showthread.php?postid=667840#post667840)

Thanks.

This I too understand. Yet gas is gas. As you can see at the schedule, where N and O is to be read as O2 and N2 the heat absorption ability is nearly the same to that of CO2.

http://pump.net/thebasics/physpropgases.htm

As for the micro-wave, here we deal with water. Water and also the vapor in the air does absorb a great deal of heat. It's classified by specific heat, meaning how much energy is required to raise the temperature of a given medium. And vapor stand out. As for the Micro-wave they are tuned to the frequency of the water molecule. The difference here is that any other radiation would heat that water also, but the micro-wave is calibrated to the frequency of water, and thus expedites the heating process. The main difference between H2O and CO2 is that the H2O molecules are polar covalent bonds and do react with radiation; and calibrating the polar bond is childsplay. I have no such luck with CO2.

I will go through your other reading suggestions and hope to find something there.  

Someone correct me if I'm wrong on this but . . . (its been 10 years since physics and chemistry)

The ability for a molecules (in this example, C02) radiation absorbtion by the chemical bonds is very different than specific heat or the gases ability to hold heat (which is what is shown in your linked chart).

Just because two or three gasses have similar specific heat values, does not mean that they absorb radiation at the same levels. Specific heat deals with how they hold heat once they have been heated.

(Does absorbtion of radiation tell us with how fast they can be heated up with radiation related to other gasses?)

 

[Mechanical Bliss]

What's being left out of the discussion of specific heat is that this is about long wavelength radiation being reflected--around the infrared part of the spectrum--not just the ability of a substance to change its temperature by a degree per unit mass.

The ability of a molecule to absorb this long wavelength radiation depends on the vibration of the molecule. Gases like N2 and O2 are only composed of two atoms per molecule, so they vibrate at a higher frequency and do not have any induced dipole moments as a result of this vibration because the two atoms are symmetric.

Although carbon dioxide is also a linear molecule, vibration of this molecule does cause the dipole moment of the molecule to change during vibration because it is not perfectly linear as it vibrates so the equal and opposite dipole moments no longer cancel each other out. Since there can be a net dipole moment change during the vibration of CO2, but not N2 or O2, this energy can be absorbed. This is similar to the situation with NO as a greenhouse gas. There must be a change in the net dipole moment of a molecule during its vibration for infrared radiation to be absorbed by it.

The point I'm trying to make, though it's difficult to say considering it's been a few semesters since organic chemistry, is that different molecules absorb energy of different wavelengths. The ability to absorb different wavelengths depends on the bonding pattern of the gas. CO2 has a different bonding scheme than the symmetric, diatomic gases mentioned, and when it vibrates, net dipole moments can be induced. The character of CO2 is unique such that it does absorb infrared radiation, but N2 and O2 do not as they only would vibrate at a higher energy state with no net dipole moment. That is to say, the incoming infrared radiation frequency will be close to the vibration frequency of CO2 but not O2/N2.

What matters here is not the specific heat (or heat requred to raise the temperature of a substance by degree--celcius--per gram), but is the absorption band of a substance, or the certain band of energy wavelengths a molecule can absorb. CO2 has a different absorption band than the diatomic gases.

 

[notto]

So, basically C02 can absorb this infrared radiation and other molecules can't for the same reason the water molecules heat up in the microwave. It has to do with specific molecules and their structure in relation to the wavelength of radiation they can absorb.

Is that correct?

 

[Mechanical Bliss]

Yessir...at least that's my understanding of it.

The "gas is gas" argument is irrelavent because different gases have different bonding structures and thus absorb different types of energy (infrared radiation, in this case) according to these different bonding structural characteristics.

 

[Lacmeh]

Itß´s all a matter of the bond between elements. That principle is used for Absorption spectroscopy. If Hank´s post would be correct, the entire Absorption spectroscopy wouldn´t work. Since the anorganic analysis uses this principle very often, it should work.
Infrared light is used in analysis of organic substances, which naturally contain very high rates of carbon. It is safe to assume, that the same principles used for identification of substances in laboratories apply to the particles in the atmosphere.

 

[Hank]

21st February 2003 at 05:58 PM Mechanical Bliss said this in Post #27
What matters here is not the specific heat (or heat requred to raise the temperature of a substance by degree--celcius--per gram), but is the absorption band of a substance, or the certain band of energy wavelengths a molecule can absorb. CO2 has a different absorption band than the diatomic gases.

 Can you show the paper for this?

21st February 2003 at 06:10 PM Mechanical Bliss said this in Post #29

Yessir...at least that's my understanding of it.

The "gas is gas" argument is irrelavent because different gases have different bonding structures and thus absorb different types of energy (infrared radiation, in this case) according to these different bonding structural characteristics.

When gases have similar characteristics, unless you can show otherwise, my statement is valid. As I wrote show the how, when, where IR hits CO2 differently by how much compared to N2 and or O2.

 

[Hank]

21st February 2003 at 06:33 PM Lacmeh said this in Post #30

Itß´s all a matter of the bond between elements. That principle is used for Absorption spectroscopy. If Hank´s post would be correct, the entire Absorption spectroscopy wouldn´t work. Since the anorganic analysis uses this principle very often, it should work.
Infrared light is used in analysis of organic substances, which naturally contain very high rates of carbon. It is safe to assume, that the same principles used for identification of substances in laboratories apply to the particles in the atmosphere.

What has the Absorption spectroscopy to do with my questions? Of course a solid will react to IR, I stated that before. That those solids are carbon bonds is incedental.

See link

http://chipo.chem.uic.edu/web1/ocol/spec/IR.htm

 

[DNAunion]

Hank: Can you show the paper for this?

DNAunion: This might work.

” Absorption spectra due to electronic transitions of molecular and atomic oxygen and nitrogen, plus ozone, occur chiefly in the ultraviolet region, while those due to the vibrational and rotational transitions of triatomic molecules (eg water vapour, carbon dioxide, ozone) lie in the infrared.” (http://ceos.cnes.fr:8100/cdrom-98/ceos1/science/dg/dg17.htm)

DNAunion: See the diff.

And a link in that page also gives a chart listing the respective absorption ranges for diatomic oxygen and carbon dioxide, and, they are much different. Here’s that link:
http://ceos.cnes.fr:8100/cdrom-98/ceos1/science/dg/dg1.htm#anchor5717807

 

[Mechanical Bliss]

Yesterday at 06:01 PM Hank said this in Post #31

 Can you show the paper for this?

DNAUnion already provided some good information including a chart.

When gases have similar characteristics, unless you can show otherwise, my statement is valid. As I wrote show the how, when, where IR hits CO2 differently by how much compared to N2 and or O2.

But the gases don't have similar characteristics from a molecular standpoint. N2 and O2 are diatomic and composed of the same atoms in a linear bonding scheme. No net dipole moment can exist. CO2 involves two atoms of oxygen separated by an atom of carbon. When this molecule vibrates, there will be a net dipole moment as the two oxygen atoms move "up" and "down" with respect to the carbon. The change in dipole moment occurs in CO2 but not N2 and O2 which is why it absorbs IR radiation.

This has to do with the absorption bands, not specific heat. Absorption bands of molecules are dependent on their molecular structure and how their vibrations affect that structure.

 

[Gooch's dad]

Hank,

Here's a great tutorial on greenhouse gases. C02 absorbs like crazy at around 2500 cm-1, which is roughly 4 microns wavelength.

http://chemistry.beloit.edu/Warming/pages/infrared.html

 

[Hank]

Today at 01:54 PM Gooch's dad said this in Post #35

Hank,

Here's a great tutorial on greenhouse gases. C02 absorbs like crazy at around 2500 cm-1, which is roughly 4 microns wavelength.

http://chemistry.beloit.edu/Warming/pages/infrared.html

Thanks dude

Also I found a good site last night

http://www.geo.cornell.edu/geology/classes/Geo101/101week13_f01.html

 

[Hank]

Today at 01:04 PM Mechanical Bliss said this in Post #34

DNAUnion already provided some good information including a chart.




But the gases don't have similar characteristics from a molecular standpoint. N2 and O2 are diatomic and composed of the same atoms in a linear bonding scheme. No net dipole moment can exist. CO2 involves two atoms of oxygen separated by an atom of carbon. When this molecule vibrates, there will be a net dipole moment as the two oxygen atoms move "up" and "down" with respect to the carbon. The change in dipole moment occurs in CO2 but not N2 and O2 which is why it absorbs IR radiation.

This has to do with the absorption bands, not specific heat. Absorption bands of molecules are dependent on their molecular structure and how their vibrations affect that structure.

I missed your post!

Thank you too.

Btw I am not done yet.