White roofs, streets could curb global warming

Sep 17, 2008 by Lisa Zyga weblog

The idea of painting our roofs and roads white to offset global warming is not new, but a recent study has calculated just how significantly white surfaces could impact greenhouse gas emissions. Last week, researchers at Lawrence Berkeley National Laboratory and UC Berkeley presented their study at California's annual Climate Change Research Conference in Sacramento.

If the 100 largest cities in the world replaced their dark roofs with white shingles and their asphalt-based roads with concrete or other light-colored material, it could offset 44 metric gigatons (billion tons) of greenhouse gases, the study shows. That amounts to more greenhouse gas than the entire human population emits in one year, according to a recent article in the Los Angeles Times. The strategy could also offset the growth in carbon dioxide emissions, which account for about 75% of greenhouse gases, for the next 10 years.

The reason for white is simple: white reflects the sun´s rays more than black does. The study´s coauthor, LBNL physicist Hashem Akbari, explained that it takes about 10 square meters of white roof to offset 1 metric ton of carbon dioxide. In warm climates, white roofs have the additional benefit of lowering the cost of air conditioning by up to 20% in hot months.

It´s this second reason of reduced cooling costs that prompted the state of California to require in 2005 that flat-roofed commercial buildings have white roofs. In 2009, the state will require that new and retrofitted residential and commercial, with both flat and sloped roofs, be installed with heat-reflective roofing. The requirements are part of California´s energy-efficient building code.

Globally, roofs account for about 25% of the surface of most cities, and pavement accounts for about 35%. Even without cutting industrial pollution from current levels, installing white roofs and pavements could offset more than 10 years of emissions growth, according to the conference data.

Economically, the scientists estimate that white roofs and roads could save billions of dollars per year in reduced carbon dioxide emissions. Besides offsetting global warming and reducing cooling costs, white surfaces offer a third benefit: they could cool a city by a few degrees, which dramatically reduces smog.

The LBNL physicists plan to work with the United Nations to persuade the world´s major tropical and temperate cities to adopt white roofing and pavement strategies.

Akbari, along with coauthors Surabi Menon of LBNL and California Energy Commissioner Arthur Rosenfield, will publish the study, called "Global Cooling: Increasing Worldwide Urban Albedos to Offset CO2," in an upcoming issue of the journal Climate Change.

More information: Global Cooling Presentation

via: Los Angeles Times

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Doggonit
3.9 / 5 (20) Sep 17, 2008
You know, people laughed when Obama suggested that keeping your tires inflated to the right pressure could save a lot of gas. But, it turned out he was right. White roofs and roads might sound silly at first as well but I bet they are right. Every little bit is going to help.
deatopmg
2.2 / 5 (26) Sep 17, 2008
I laughed (after I picked myself up off the floor) when Obama said that there were ...uh, about 57 states... in the uSA - ( 50 isn't even "about 57") so based on that we have to discount properly inflated tires and just about everything else the pol says. White roofs and roads are another thing though.
Ausjin
3.2 / 5 (12) Sep 17, 2008
Asphalt was chosen to be our primary pavement for more than just being cheap. In terms of traction, there is no better surface. Would there be any safety issues that would arise if we suddenly switched to concrete roads?
barakn
2.7 / 5 (11) Sep 17, 2008
Asphalt gets rid of ice and snow faster at higher latitudes.
Roach
3.8 / 5 (13) Sep 17, 2008
Working at a facility with silver roofs on some equipment, tanks and such, light color only helps as long as you can keep it clean and rain does little to help and more to obscure the color. As far as concrete roads, the biggest thing I remember about them, if I remember right East Germany, wow, that's an out dated referance, had them and they were more prone to problematic cracking and more dificult to repair well. Asphalt naturally heals itself with small cracks where concrete cracks tend to grow rather quickly. It's also more expensive to build a concrete road. Wouldn't another issue would be an increase in glare?
@barakn
But look at the positive, it'd be easy to see the black ice on the road...j/k
THEY
3.6 / 5 (9) Sep 17, 2008
Most UPS trucks have white paint on the roof to keep them cooler.

I can't imagine how I would drive with the awful glare from white roads, but I would contemplate a light colored roof.
alq131
2.4 / 5 (10) Sep 17, 2008
I didn't understand where they were saying all the greenhouse gas emissions saved would come from. Is it that asphalt is a petrochemical product, and it's more costly to manufacture? I could see moving to concrete would use less oil, but asphalt is essentially a by product of gasoline production's fractionization process
GrayMouser
4.2 / 5 (12) Sep 17, 2008
Asphalt also out-gasses a bunch of really neat aromatic compounds...
Wasabi
4.6 / 5 (9) Sep 17, 2008
Valid or not we really could stand to rethink asphalt. It's been around a long, long time with very little improvement over the decades, would be nice to see science take a good long look at it and see what they can come up with for a more durable, less oil dependent etc. surface.
MikeB
3 / 5 (16) Sep 17, 2008
It would be a good idea if everyone wore white hats like the good guys. :)
We should also purchase only white pets. In the stores, only white paint should be sold. We better get busy, we have a bunch of laws to write. :)
TJ_alberta
4.5 / 5 (10) Sep 17, 2008
white on flat roofs is SOP in hot climates. The new polymer roofing compounds (white) are very durable and certainly easier, safer and longer lasting than hot tar. Don't people in the southern US use these white roofing compounds? In desert climates, where there is no rain to wash the dust off the roof a broom and garden hose work well.
NotParker
2.2 / 5 (17) Sep 17, 2008
So ... dark roogs cause AGW? Not Co2?

Wow. Big news!
kerry
4.3 / 5 (10) Sep 18, 2008
White roofs reflect more energy as light rather than storing as heat. Less heat means less air conditioning use. Less air conditioning use means less coal burned. Less coal burned means less CO2 released. That's my theory, at least.
Dismay
3 / 5 (5) Sep 18, 2008
Or instead of white roofs, have community's with parabolic solar reflectors and a collector in the center. The reflected light will keep the house cooler providing the benefits of reduced air conditioning use, and the community would split power credits generated by the solar collector. New housing developments could be constructed with this in mind, the placement, architecture, roof angle etc could be optimized for solar collection. Solar Community tm :)
sleidia
3.5 / 5 (10) Sep 18, 2008
Hey guys, white roads doesn't necesserally means concrete. There must be a way to create white asphalt ... or like Wasabi said, rethink asphalt.

Some people really lack some imagination :)
fleem
2.8 / 5 (10) Sep 18, 2008
NotParker I thought the same thing--how much do black roofs, compared to natural ground cover, ~contribute~ to global warming? Maybe roof color effects the temperature more than carbon emission ? In any case I do believe the satellite sensors are also right--solar output really has increased by what those sensors show (which translates to .7C degrees per century), plus there's the same sort of short-term variation astronomers see in other stars.

Another question I didn't see answered in the article: did the researchers consider the carbon that would be emitted to produce and apply the white?
mikiwud
3.3 / 5 (9) Sep 18, 2008
Cement (for concrete) production is one of the main producers of carbon dioxide.
Every "up" has a "downside".
flubber
4.6 / 5 (9) Sep 18, 2008
more prone to problematic cracking and more dificult to repair well.


Epoxy compound...

Asphalt naturally heals itself with small cracks


Not really.

concrete cracks tend to grow rather quickly. It's also more expensive to build a concrete road.


Yup, but they last longer.

But look at the positive, it'd be easy to see the black ice on the road...j/k


Nope, black ice is a very thin CLEAR coating.

Also, asphalt can be made in almost any color, but ya'll wouldn't wanna pay for it.
MHR
3.5 / 5 (14) Sep 18, 2008
anti-gravity hovercars would solve everything.
chewi
1.8 / 5 (13) Sep 18, 2008
How does reflecting sunlight off of roads curb global warming? I thought once sunlight made it into the atmosphere, and was reflect around it's energy remained in the atmosphere... still going have the heat, maybe higher, but overall the heat is not escaping or is it?
Falcon
4.6 / 5 (9) Sep 18, 2008
How does reflecting sunlight off of roads curb global warming? I thought once sunlight made it into the atmosphere, and was reflect around it's energy remained in the atmosphere... still going have the heat, maybe higher, but overall the heat is not escaping or is it?
Yes but instead of absorbing the light and creating heat with the black color, white will reflect the light and remain cooler. Seriously go into a car lot and feel a black car and a white car. Notice any difference? Our main problem is getting the heat out of the atmosphere not the light (i think). Im no scientist but that seems to make since because i have heard that greenhouse gasses trap heat but i never heard that it trapped light. Hell when volcanoes erupt it sends ash into the air that clouds the sky with ash causing a small cooling trend.
Roach
4.5 / 5 (8) Sep 18, 2008
Flubber;
My Experiance with concrete epoxy repairs has been increased spalling unless the surface is cleaned abraded and pretreated. Kind of pricy and certainly more dificult that squirting in some tar.
The oil base in asphalt does reseal cracks what it does not do and what most people see is address subsurface issues such as poor road base or errosion, concrete would have the same problem.
Even with all the downs I'll agree concretes roads well maintained do last a while.
and the Black Ice comment was purely a joke.
I agree that asphalt can be dyed, but I think you are limited to darker colors with true asphalt.
Falcon:
Light=heat. But you are close, Long wavelengths like those emited by dark anythings have a harder time punching though the upper atmosphere as well as high frequency waves can get in light or highly reflective materials push back closer to what is coming in making it easier to get back out. Kinda the way the atmosphere filters UV moreso than IR.
GrayMouser
3 / 5 (6) Sep 18, 2008
Valid or not we really could stand to rethink asphalt. It's been around a long, long time with very little improvement over the decades, would be nice to see science take a good long look at it and see what they can come up with for a more durable, less oil dependent etc. surface.


Robert A. Heinlein came up with a solution. "Let the roads roll"
fleem
4.3 / 5 (6) Sep 18, 2008
"Robert A. Heinlein came up with a solution. "Let the roads roll"

Yeah, but do you remember the big accident in that book? LPC -- Large Pedestrian Collider.
murf26
5 / 5 (7) Sep 19, 2008
I used to live in Lake Charles, Louisiana. It got very warm down there and if I remember correctly, the streets and roads were made of Portland cement which greatly reduced the temperature of the road. I rode a bicycle to school everyday and could really tell a difference...
KenWD0ELQ
4.6 / 5 (9) Sep 19, 2008
I've been telling people for YEARS to have white (or light-color) roofs to keep the house cool. And from the time people started getting all exercised about "global warming", I've been telling folks that white roads would do more, cheaper, than all of the CO2 insanity in the world.

I'm glad that somebody is finally listening. But it ought to have been GLARINGLY obvious....
MikeB
2.8 / 5 (9) Sep 20, 2008
Speaking of obvious, if we're going to have white roads, won't we need white tires too?
Bazz
4.2 / 5 (5) Sep 21, 2008
Yes ,obviously.
Going
3.3 / 5 (6) Sep 21, 2008
You can roll a layer of white chips into the surface of asphalt and you have a white road with all the properties of an asphalt one.
sundoc
2.3 / 5 (12) Sep 21, 2008
Repave the entire US and make our roofs white.

What an overkill for some absurdly miniscule gain in "preventing global warming" which is not man made anyhow.

Wow.

That's practical.

Once he's elected, just have your Messiah shut off all the volcanoes and that'll do it. Its the CO2, dummy.
superhuman
4.4 / 5 (9) Sep 21, 2008
Just to clear up some confusion:

Solar radiation is both absorbed and reflected by objects on Earth.

White surfaces reflect much more solar infrared radiation (IR, infrared radiation is the type of electromagnetic radiation associated with heat transfer) then they absorb, the opposite is true for dark ones.

Large portion of energy reflected back into atmosphere will eventually escape into space (being absorbed and reemitted many times on its way).

IR energy which is not reflected into the atmosphere is trapped as heat on Earth surface which leads to rise in surface temperature.

So by changing to white surfaces we lower the ability of human structures to trap heat, which in turn should lower average global temperature.

This change in global temperature is equivalent to lowering global CO2 emissions by some amount.

This is what they mean when they say this strategy could offset CO2 emissions.
sundoc
1.6 / 5 (10) Sep 23, 2008
Correct me if I'm wrong, but won't the heat be reflected right back to earth? Mebee heating up the air below the beloved ozone layer? Would that raise the ambient lower atmosphere temperature?

Bah...I seriously doubt the number would be significant or offset your "CO2 footprint". And b4 you start...our CO2 emmisions are NOT the cause of global warming. The hubris of man to believe that we are the cause of such change....

Be worth a look to see if cooling costs would be lower with lighter shades of roofing or reflective surfaces tho.
Bazz
3.4 / 5 (9) Sep 23, 2008
Sundoc, whats your reason for believing that?
Velanarris
2.8 / 5 (9) Sep 24, 2008
This isn't really an interesting study. Anyone ever seena picture of Morocco from the Straight of Gibraltar? They build everything with either white materials or they paint them white specifically to reflect rather than absorb the heat from the sun.
sundoc
1.9 / 5 (9) Sep 24, 2008
The theory of Global Warming assumes that CO2 is the most important atmospheric greenhouse gas and as it increases temperatures rise. It is supposed that since humans are producing more CO2 than before, the temperature must inevitably rise. The theory was accepted before testing had started, and effectively became a law.

There is no scientifically valid mechanism for CO2 causing global warming. The truth is that carbon dioxide cannot trap radiant energy near the surface of the earth. The insignificant increase in ppm of CO2 is easily stabilized by the oceans for one, which regulate the amount of CO2 in the air through absorption equilibrium. I'll also say global warming is happening, but the majority of the current warming cycle preceeds 1940!

Global warming has been seized upon by political opportunists who proceed to claim the moral high ground by appealing to natural instinct to protect children and the world for future mankind. Combining such sentiments with religiosity and an adolescent 'we can do anything' approach, they end up with assertions so removed from the real world as to be laughable, were the consequences not so serious.
Bazz
3 / 5 (8) Sep 25, 2008
There is a small possibility that there is an alternative explanation instead of the accepted mechanism described by science.So far many have tried but noone as a convincing alternative.

Do you agree with velanarris that its a conspiracy? Or do you have better arguments to discredit the findings of some of the biggest and most trusted scientific organisations?

I hope you do.
Velanarris
2.5 / 5 (11) Sep 25, 2008
There is a small possibility that there is an alternative explanation instead of the accepted mechanism described by science.So far many have tried but noone as a convincing alternative.

Do you agree with velanarris that its a conspiracy? Or do you have better arguments to discredit the findings of some of the biggest and most trusted scientific organisations?

I hope you do.


Well if there is a mechanism that we don't understand that's acting as a driving force, then your statements of "All scientists KNOW that Humans are causing global warming" is intellectual mistreatment and generalization.
Bazz
2.8 / 5 (9) Sep 25, 2008
You trying to do a bazz on me? If you want to i can imagine but if you going to be that anal, there is no such post in this thread.But i suppose you didnt liked to be connected to the word conspiracy.

I suppose that was a little mean but you deserved it, karma if you like.

In other threads i suppose i have said something like,the overwhelming majority of climate scientists agree on, global climate change is happening and CO2 is the main driver of the change.

There is no real discussion there, that has been done many years ago, skeptic scientists had time to disprove that but they didnt so far.

There is no way i phrased"All scientists KNOW that Humans are causing global warming".If i did i would have been factually wrong and would be expected to be criticised.
This is the first time you bring it up, either i messed up, or you are trying to mess with me like you have tried before.

So you either deserve a rectification wich i have given here or disrespect from all.
Velanarris
2.7 / 5 (12) Sep 26, 2008
You trying to do a bazz on me? If you want to i can imagine but if you going to be that anal, there is no such post in this thread.But i suppose you didnt liked to be connected to the word conspiracy.

I suppose that was a little mean but you deserved it, karma if you like.

In other threads i suppose i have said something like,the overwhelming majority of climate scientists agree on, global climate change is happening and CO2 is the main driver of the change.
But they don't. There is no discernable majority on the issue. There is simply the loudest and most well backed financially.

There is no real discussion there, that has been done many years ago, skeptic scientists had time to disprove that but they didnt so far.
But scientists don't have to disprove a theory. Scientists have to prove a theory is a truth. AGW is a hypothesis, not a theory, and certainly not a truth.
Bazz
2.8 / 5 (9) Sep 26, 2008
So not the scientists with the best arguments are taken seriously?

Scientific truths are whats accepted to be true by the whole scientific community, the whole point is what is the best explanation.

Noone has to prove a theory if its convincing other scientists have to disprove the theory for it to go away, therefore many theories can live next to each other and compete to become the dominant theory.

The dominant theory is that CO2 is the main driver of climate change, there are other theories but they dont convince the majority of scientists/organisations/governments.

Show me that my theory is wrong by giving me information how this mechanism i describe is wrong, and not some web page, or a marginal research centre like the heartland institute wich is as trustworty as the greenpeace homepage for unbiased information.

Prove me wrong by showing me a representative and unbiased organisation that disagrees with my assumption that i can trust the general concensus among scientists.

Velanarris
2.7 / 5 (12) Sep 26, 2008
Well first, do me a great favor and lay out exacty how CO2 is increasing the world's temperature, and if possible elaborate as to by how much we can expect to see the teperature rise. Once you do that, I can speak to the value of your position, or against it.
Bazz
2.6 / 5 (10) Sep 27, 2008
CO2 is generating enery itself, they are tiny little zero point enery generator,Tesla told me in a dream.

And Tesla is omniscient,end of dicussion.
Velanarris
2.7 / 5 (13) Sep 27, 2008
CO2 is generating enery itself, they are tiny little zero point enery generator,Tesla told me in a dream.

And Tesla is omniscient,end of dicussion.


This is why I can't take a debate with you seriously.
Bazz
3.3 / 5 (7) Sep 28, 2008
Any one cares to point out the irony here?
MikeB
2.4 / 5 (10) Sep 28, 2008
No, but I believe that it is rather odd that a twelve year old child is commenting on this board. Does mom know you are using her computer?
GrayMouser
2.7 / 5 (7) Oct 17, 2008
Noone has to prove a theory if its convincing other scientists have to disprove the theory for it to go away, therefore many theories can live next to each other and compete to become the dominant theory.


This is so VERY wrong. You HAVE to prove a theory not disprove it.

More, if you can falsify the input, and no one can prove that you did, the entire theory becomes unprovable.
deepsand
3.5 / 5 (11) Oct 17, 2008
The theory of Global Warming assumes that CO2 is the most important atmospheric greenhouse gas and as it increases temperatures rise. It is supposed that since humans are producing more CO2 than before, the temperature must inevitably rise. The theory was accepted before testing had started, and effectively became a law.

Quite wrong; see following.

There is no scientifically valid mechanism for CO2 causing global warming.

It's called "radiative forcing." It's an inescapable result of the Physical Laws of Nature.
deepsand
3.3 / 5 (12) Oct 17, 2008
AGW is a hypothesis, not a theory, and certainly not a truth.

Absolutely false.

1) Radiative forcing is a fact, not an hypothesis.

2) That CO2 contributes to radiative forcing is a fact, not an hypothesis.

3) That mankind's actions contribute to atmospheric CO2 is a fact, not an hypothesis.

QED, mankind's actions contribute to radiative forcing, i.e. to an increase in systemic thermal energy.

You have been previously challenged, on multiple ocassions, to disprove radiative forcing, and have so far failed to offer any substantive counter.

It is you and your ilk who insist that others bow to your unsubstantiated claims.
Velanarris
2.2 / 5 (10) Oct 17, 2008
AGW is a hypothesis, not a theory, and certainly not a truth.

Absolutely false.

1) Radiative forcing is a fact, not an hypothesis.

I never said it was a hypothesis, however, radiative forcing is not AGW.

2) That CO2 contributes to radiative forcing is a fact, not an hypothesis.
Ok, that's not correct. Radiative forcing is not an action, it's a measure of net irradiance defined in Watts per square meter.

3) That mankind's actions contribute to atmospheric CO2 is a fact, not an hypothesis.

Correct, but that does not constitute AGW. You're making leaps in logic without proving anything.

QED, mankind's actions contribute to radiative forcing, i.e. to an increase in systemic thermal energy.
Your definition of radiative forcing is wrong.

You have been previously challenged, on multiple ocassions, to disprove radiative forcing, and have so far failed to offer any substantive counter.

It is you and your ilk who insist that others bow to your unsubstantiated claims.

I'm sorry, I've done it many times, mathematically, logically, and through the data sets and models used by AGW proponents. I've throw out effective volumes of data on what radiative forcing actually is, how it's measured, and to what extent CO2 affects radiative forcing. If you ant to ignore my arguments then we can look at yours, but, you haven't made one. So here's your chance.

Please elaborate as to the method that CO2 increases the effect of radiative forcing according to the scientific definition:

Radiative forcing is the change in net irradiance at the tropopause. "Net irradiance" is the difference between the incoming radiation energy and the outgoing radiation energy in a given climate system and is thus measured in Watts per square meter.

Be specific, you're proving a hypothesis here.
Excalibur
3.5 / 5 (11) Oct 17, 2008
AGW is a hypothesis, not a theory, and certainly not a truth.

Absolutely false.

1) Radiative forcing is a fact, not an hypothesis.

I never said it was a hypothesis, however, radiative forcing is not AGW.

This is a red herring; I did not state that radiative forcing was AGW.

2) That CO2 contributes to radiative forcing is a fact, not an hypothesis.

Ok, that's not correct. Radiative forcing is not an action, it's a measure of net irradiance defined in Watts per square meter.

To repeat, radiative forcing is a real physical process, one that unavoidably derives from the Physical Laws of Nature; it is NOT, as you persist on describing it, an observational artifact. This is the FUNDAMENTAL FLAW IN YOUR POSITION.

3) That mankind's actions contribute to atmospheric CO2 is a fact, not an hypothesis.

Correct, but that does not constitute AGW. You're making leaps in logic without proving anything.

The logical flaw is yours, owing to your incorrectly holding radiational forcing to be something that it is not.
QED, mankind's actions contribute to radiative forcing, i.e. to an increase in systemic thermal energy.
Your definition of radiative forcing is wrong.

Rebutted above.
You have been previously challenged, on multiple ocassions, to disprove radiative forcing, and have so far failed to offer any substantive counter.

It is you and your ilk who insist that others bow to your unsubstantiated claims.

I'm sorry, I've done it many times, mathematically, logically, and through the data sets and models used by AGW proponents. I've throw out effective volumes of data on what radiative forcing actually is, how it's measured, and to what extent CO2 affects radiative forcing. If you ant to ignore my arguments then we can look at yours, but, you haven't made one. So here's your chance.

You've done nothing other than repeat your flawed definition of radiative forcing; and, mis-direct by way of venturing into non-radiational issues such as conduction and convection. You've even gone so far as to claim a magical quality that causes CO2 to absorb, but not re-radiate, IR at low altitudes, and re-radiate, but not absorb, such at high altitudes.

Continued recitations of data and flawed understandings will not serve to set aside the Physical Laws of Nature.

Please elaborate as to the method that CO2 increases the effect of radiative forcing according to the scientific definition:

Radiative forcing is the change in net irradiance at the tropopause. "Net irradiance" is the difference between the incoming radiation energy and the outgoing radiation energy in a given climate system and is thus measured in Watts per square meter.


This is not, as previously noted, a proper definition of radiative forcing. It conflates radiative forcing with the Terran radiation balance; though related, the two are quite different things.
Velanarris
2.2 / 5 (10) Oct 18, 2008

I never said it was a hypothesis, however, radiative forcing is not AGW.

This is a red herring; I did not state that radiative forcing was AGW.
If you notice I was responding to deepsand, that is, unless you are also deepsand, in which case, yes you did.
Ok, that's not correct. Radiative forcing is not an action, it's a measure of net irradiance defined in Watts per square meter.

To repeat, radiative forcing is a real physical process, one that unavoidably derives from the Physical Laws of Nature; it is NOT, as you persist on describing it, an observational artifact. This is the FUNDAMENTAL FLAW IN YOUR POSITION.
It is the sum of the pysical processes that transfer energy into or out of the tropopause measured in Watts per square meter. At what point in time did I state it was an artifact of observational data? You're creating semantics arguments to create a non-existant debate so you can attempt to back up your position.


Correct, but that does not constitute AGW. You're making leaps in logic without proving anything.

The logical flaw is yours, owing to your incorrectly holding radiational forcing to be something that it is not.
You're incorrect.

QED, mankind's actions contribute to radiative forcing, i.e. to an increase in systemic thermal energy.
Your definition of radiative forcing is wrong.

Rebutted above.
Not at all.

You have been previously challenged, on multiple ocassions, to disprove radiative forcing, and have so far failed to offer any substantive counter.

It is you and your ilk who insist that others bow to your unsubstantiated claims.

I'm sorry, I've done it many times, mathematically, logically, and through the data sets and models used by AGW proponents. I've throw out effective volumes of data on what radiative forcing actually is, how it's measured, and to what extent CO2 affects radiative forcing. If you ant to ignore my arguments then we can look at yours, but, you haven't made one. So here's your chance.

You've done nothing other than repeat your flawed definition of radiative forcing; and, mis-direct by way of venturing into non-radiational issues such as conduction and convection. You've even gone so far as to claim a magical quality that causes CO2 to absorb, but not re-radiate, IR at low altitudes, and re-radiate, but not absorb, such at high altitudes.
I'm sorry, what? At what point in time did I say CO2 does not re-radiate?

Continued recitations of data and flawed understandings will not serve to set aside the Physical Laws of Nature.
These physical laws of nature you keep touting include one called transferrence equilibrium. You're probably not too keen on that one.

Please elaborate as to the method that CO2 increases the effect of radiative forcing according to the scientific definition:

Radiative forcing is the change in net irradiance at the tropopause. "Net irradiance" is the difference between the incoming radiation energy and the outgoing radiation energy in a given climate system and is thus measured in Watts per square meter.


This is not, as previously noted, a proper definition of radiative forcing. It conflates radiative forcing with the Terran radiation balance; though related, the two are quite different things.
Yes, the terran radiation balance is the entire planet and includes all possible radiation. Radiative forcing is the balance in the troposphere.

So I ask the same question, answer it.

Here are your definitions again:

The relative effectiveness of greenhouse gases to restrict long-wave radiation from escaping back into space. For a particular greenhouse gas, radiative forcing is measured as the change in average net radiation (in watts per square meter) at the top of the troposphere, and depends on the wavelength at which the gas absorbs the radiation, the strength of absorption per molecule, and the concentration of the gas. from http://www.answer...-forcing

In climate science, radiative forcing is (loosely) defined as the change in net irradiance at the tropopause. "Net irradiance" is the difference between the incoming radiation energy and the outgoing radiation energy in a given climate system and is thus measured in Watts per square meter. From wikipedia

A measure of the influence that a climatic factor (e.g. ice albedo, tropospheric aerosols) has in altering the balance of incoming and outgoing energy in the Earth-atmosphere system. Also used as an index of the influence a factor has as a potential climate change mechanism.

http://www.eoeart..._forcing
Velanarris
2.3 / 5 (9) Oct 18, 2008
As a suppliment, you may want to go read this before you respond again.

http://www.nap.ed...id=11175&page=R1
Excalibur
4.2 / 5 (10) Oct 20, 2008

I never said it was a hypothesis, however, radiative forcing is not AGW.

This is a red herring; I did not state that radiative forcing was AGW.
If you notice I was responding to deepsand, that is, unless you are also deepsand, in which case, yes you did.
Ok, that's not correct. Radiative forcing is not an action, it's a measure of net irradiance defined in Watts per square meter.

To repeat, radiative forcing is a real physical process, one that unavoidably derives from the Physical Laws of Nature; it is NOT, as you persist on describing it, an observational artifact. This is the FUNDAMENTAL FLAW IN YOUR POSITION.
It is the sum of the pysical processes that transfer energy into or out of the tropopause measured in Watts per square meter. At what point in time did I state it was an artifact of observational data? You're creating semantics arguments to create a non-existant debate so you can attempt to back up your position.


Correct, but that does not constitute AGW. You're making leaps in logic without proving anything.

The logical flaw is yours, owing to your incorrectly holding radiational forcing to be something that it is not.
You're incorrect.

QED, mankind's actions contribute to radiative forcing, i.e. to an increase in systemic thermal energy.
Your definition of radiative forcing is wrong.

Rebutted above.
Not at all.

You have been previously challenged, on multiple ocassions, to disprove radiative forcing, and have so far failed to offer any substantive counter.

It is you and your ilk who insist that others bow to your unsubstantiated claims.

I'm sorry, I've done it many times, mathematically, logically, and through the data sets and models used by AGW proponents. I've throw out effective volumes of data on what radiative forcing actually is, how it's measured, and to what extent CO2 affects radiative forcing. If you ant to ignore my arguments then we can look at yours, but, you haven't made one. So here's your chance.

You've done nothing other than repeat your flawed definition of radiative forcing; and, mis-direct by way of venturing into non-radiational issues such as conduction and convection. You've even gone so far as to claim a magical quality that causes CO2 to absorb, but not re-radiate, IR at low altitudes, and re-radiate, but not absorb, such at high altitudes.
I'm sorry, what? At what point in time did I say CO2 does not re-radiate?

Continued recitations of data and flawed understandings will not serve to set aside the Physical Laws of Nature.
These physical laws of nature you keep touting include one called transferrence equilibrium. You're probably not too keen on that one.

Please elaborate as to the method that CO2 increases the effect of radiative forcing according to the scientific definition:

Radiative forcing is the change in net irradiance at the tropopause. "Net irradiance" is the difference between the incoming radiation energy and the outgoing radiation energy in a given climate system and is thus measured in Watts per square meter.


This is not, as previously noted, a proper definition of radiative forcing. It conflates radiative forcing with the Terran radiation balance; though related, the two are quite different things.
Yes, the terran radiation balance is the entire planet and includes all possible radiation. Radiative forcing is the balance in the troposphere.

So I ask the same question, answer it.

Here are your definitions again:

The relative effectiveness of greenhouse gases to restrict long-wave radiation from escaping back into space. For a particular greenhouse gas, radiative forcing is measured as the change in average net radiation (in watts per square meter) at the top of the troposphere, and depends on the wavelength at which the gas absorbs the radiation, the strength of absorption per molecule, and the concentration of the gas. from http://www.answer...-forcing

In climate science, radiative forcing is (loosely) defined as the change in net irradiance at the tropopause. "Net irradiance" is the difference between the incoming radiation energy and the outgoing radiation energy in a given climate system and is thus measured in Watts per square meter. From wikipedia

A measure of the influence that a climatic factor (e.g. ice albedo, tropospheric aerosols) has in altering the balance of incoming and outgoing energy in the Earth-atmosphere system. Also used as an index of the influence a factor has as a potential climate change mechanism.

http://www.eoeart..._forcing

Both deepsand and I have repeatedly attempted, in numerous threads, to correct your flawed understanding of the definition of radiative (or, radiational) forcing. It is NOT related to any particular body or system, and it is NOT an OBSERVED NET EFFECT. I.e., it is NOT "... the sum of the pysical processes that transfer energy into or out of the tropopause measured in Watts per square meter."

It is a very specific physical PROCESS, one that relates to ANY irradiated body that is surrounded by by an interface whose transmissivity is non-uniform with respect to wavelength. It is wholly independent of the observational data which you are so fond of proclaiming.

The definition which you so loosely toss about is that of "radiation balance," for which radiative forcing is but a single input.

Quoting a Wikipedia definition that itself says "loosely defined," and that is also incorrectly worded - "loosely defined" should be "loosely MEASURED" - will not serve to alter the fact that radiative forcing is a process wholly independent of climatology.

You would do better to look to the process of spectral absorption physics for an understanding of radiative forcing.

Now, we still await your explanation of the magical powers of CO2 to absorb/re-radiate IR according to altitude.

Velanarris
2.5 / 5 (11) Oct 21, 2008
Ok, here's your supposedly magical CO2 powers.


It's called, thermodynamic equilibrium.

When you add energy to a gaseous system the energized molecules will vibrate at a higher frequency (CO2 absorbing IR at low altitude). This creates an excited state in the molecule. Molecules don't like being excited so they will attempt to retransmit the energy (omnidirectional re-radiation). So far you and I are in complete agreement of how everything works.

Here's where we diverge:

In order to transmit this energy the molecule must be able to pass this energy into a molecule of lower effective energy through contact or radiation. As CO2 is a well mixed gas the energy is effectively absorbed equally amongst all molecules of the same elevation. Meaning that the energy cannot be transmitted from one excited molecule to another excited molecule. This is saturation.

Since saturated molecules are more energetic they will move more rapidly than the ambient surrounding O2 and N2 molecules. As the O2 and N2 molecules won't absorb the energy from the CO2 molecules this causes the CO2 to rise in altitude until such a point that they meet less energetic molecules capable of absorbing the excess energy. At that point in time they will re-radiate omnidirectionally and the process will start again from a higher altitude until it hits the tropopause where the energy will be transferred out of the system.

This is otherwise known as convection and the processes described above are completely in line with "THE PHYSICAL LAWS OF THE UNIVERSE" as you put it.

deepsand
3.9 / 5 (11) Nov 28, 2008
As CO2 is a well mixed gas the energy is effectively absorbed equally amongst all molecules of the same elevation. Meaning that the energy cannot be transmitted from one excited molecule to another excited molecule. This is saturation.

The IR energy is NOT ABSORBED EQUALLY.

A given photon, at a given wavelength, can have its energy absorbed by one molecule only; its energy cannot be split amongst multiple molecules. Therefore, "saturation" can occur only when each and every molecule is excited.

Add more molecules, and more photons can be absorbed.

Since saturated molecules are more energetic they will move more rapidly than the ambient surrounding O2 and N2 molecules. As the O2 and N2 molecules won't absorb the energy from the CO2 molecules this causes the CO2 to rise in altitude until such a point that they meet less energetic molecules capable of absorbing the excess energy.

Re-radiation happens regardless of the presence or absence of other molecules capable of absorbing said radiation; such is INDEPENDENT OF ALTITUDE.

This is otherwise known as convection and ...

is WHOLLY SEPARATE FROM and INDEPENDENT OF the issues of SPECTRAL ABSORPTION & RADIATIVE FORCING.
deepsand
3.7 / 5 (9) Nov 28, 2008
It's called, thermodynamic equilibrium.

And, its CONSEQUENCE.

You've mistaken effect for cause.
Velanarris
1.9 / 5 (9) Nov 28, 2008
As CO2 is a well mixed gas the energy is effectively absorbed equally amongst all molecules of the same elevation. Meaning that the energy cannot be transmitted from one excited molecule to another excited molecule. This is saturation.

The IR energy is NOT ABSORBED EQUALLY.

A given photon, at a given wavelength, can have its energy absorbed by one molecule only; its energy cannot be split amongst multiple molecules. Therefore, "saturation" can occur only when each and every molecule is excited.

Add more molecules, and more photons can be absorbed.
Equally within the system, frame of reference semantics. Secondly more molecules will absorb more photons, that is true, however, there are only so many photons to absorb. Unless the sun is casting more energy on the planet you have already absorbed all the photons at the given wavelength, hence the term SATURATION.


Since saturated molecules are more energetic they will move more rapidly than the ambient surrounding O2 and N2 molecules. As the O2 and N2 molecules won't absorb the energy from the CO2 molecules this causes the CO2 to rise in altitude until such a point that they meet less energetic molecules capable of absorbing the excess energy.

Re-radiation happens regardless of the presence or absence of other molecules capable of absorbing said radiation; such is INDEPENDENT OF ALTITUDE.
And when dealing with a system that is NOT HOMOGENOUS, factors of location such as ALTITUDE do make a difference. This is rather simply evidenced by the mechanic of heat rising.
Secondly, re-radiation has great pertinence in regard to the presence of more molecules. If you wanted to push the radiative forcing argument properly you'd know that without additional molecules to re-absorb the radiation it would completely escape the system making the second tennant of radiative forcing a moot point.
This is otherwise known as convection and ...

is WHOLLY SEPARATE FROM and INDEPENDENT OF the issues of SPECTRAL ABSORPTION & RADIATIVE FORCING.
Absolutely not. We're taking about energy changing from infrared to thermal due to spectral absorption by CO2. You can't say that the mechanics of the energy when it's in one state are wholly seperate and independant of the effects of the enegry in a second state. It is one system, the second half of which radiative forcing proponents choose to ignore. Which is exactly why radiative forcing does not explain anything, nor is it a viable reasoning for CO2 being the GHG culprit responsible for AGW.

It's called, thermodynamic equilibrium.

And, its CONSEQUENCE.

You've mistaken effect for cause.


No, you've mistaken a half truth for a whole truth. Both sides of the equation have to be examined otherwise any resultant data sets comming from the flawed formula are fundamentally flawed.
superhuman
3.7 / 5 (9) Nov 30, 2008
V once again you prove how miserable is your understanding of physics. Ive pointed out nonsense in countless posts of yours yet you still feel entitled to teaching others.

The funniest thing is I once saw you claim in a post on this site that you have a degree in physics! LOL! I should have bookmarked it and attach a link each time you come up with another brilliant theory.


It's called, thermodynamic equilibrium.

When you add energy to a gaseous system the energized molecules will vibrate at a higher frequency (CO2 absorbing IR at low altitude). This creates an excited state in the molecule. Molecules don't like being excited so they will attempt to retransmit the energy (omnidirectional re-radiation). So far you and I are in complete agreement of how everything works.

Here's where we diverge:

In order to transmit this energy the molecule must be able to pass this energy into a molecule of lower effective energy through contact or radiation. As CO2 is a well mixed gas the energy is effectively absorbed equally amongst all molecules of the same elevation. Meaning that the energy cannot be transmitted from one excited molecule to another excited molecule. This is saturation.


This is nonsense.

1. The molecule radiates anyway, it just won't be absorbed by another molecule if it already is in excited state.

2. The molecules don't all have equal energy their energy is given by Maxwell Boltzmann distribution (the mean value is most probable and the farther from the mean you go the lower the probability for finding a molecule with such energy)

3. It is completely absurd to claim that all molecules will absorb the same and be in the same state. The energy is not absorbed equally, the probability of absorption depends on the state of absorbing molecules, in fact most absorption occurs during collisions of two molecules due to spectral broadening.

3. Its IMPOSSIBLE for all molecules in the atmosphere (or part of it) to be in the excited state, the energy they absorb as IR radiation is immediately converted to vibrations = heat.

What actually happens is that some molecules are more efficient in absorbing radiation and converting it to heat then others, it depends on their chemical structure. CO2 for example is much more potent when it comes to absorbing IR radiation and converting it into heat then O2 or N2, on the other hand they are all very inefficient when it comes to converting from heat back to radiation.

In other words a significant part of energy passing through the atmosphere as IR radiation is caught by CO2 and converted into heat. This lowers the effective cooling of the planet.


Since saturated molecules are more energetic they will move more rapidly than the ambient surrounding O2 and N2 molecules. As the O2 and N2 molecules won't absorb the energy from the CO2 molecules this causes the CO2 to rise in altitude until such a point that they meet less energetic molecules capable of absorbing the excess energy.


This is complete nonsense.

There are no saturated molecules, the absorbed IR energy is converted into heat - kinetic energy of molecular motions, the energy of those motions is transferred in collisions and of course O2 and N2 partake in those collisions, and thermal energy is equally well spread among all constituents of the atmosphere at a given latitude.

This is otherwise known as convection and the processes described above are completely in line with "THE PHYSICAL LAWS OF THE UNIVERSE" as you put it.


LOL!

Here is some basic reading on the subject, please try to UNDERSTAND it before you type another nonsense:

http://en.wikiped...se_gases
http://en.wikiped...ribution
Velanarris
1.9 / 5 (9) Dec 01, 2008
Hey, SH. You do realize you have just disproven the tennets of radiative forcing as lain out by the IPCC to justify CO2 as a major GHG.

Good work.
Velanarris
2.2 / 5 (10) Dec 01, 2008
It's just priceless how one can be steered into disproving their own ridiculous beliefs when those beliefs are built on tom foolery.

SH, what you outlined above is very accurate, and completely contrary to the description and explaination lain out for radiative forcing in both the IPCC 1st and 2nd reviews of climate change.

Their reasoning behind obscuring the actual physics were because the actual physics don't work out as they dictated and in turn change the MMGW figure for 50% culpable to about 5% culpable. Good work, thanks for setting us all straight.
superhuman
3.1 / 5 (9) Dec 02, 2008

SH, what you outlined above is very accurate...


So what does that make your statements?

Completely inaccurate, misleading and wrong?

Can you actually admit for once that you were wrong? Or do you always try to spin it your way, no matter how silly it looks?

Think about it for a moment, you keep posting all that anti GW nonsense in every topic that has anything to do with climate, yet I just showed you how you completely fail to understand the science behind it!

Wasn't all this anti GW crusade based on your misunderstanding of the issue?

Now when you know that all your understanding is invalid should you not reconsider your position?

Does it occur to you that maybe IPPC was right all along?

Do you realize that you either have to really learn the science or just leave the topic to others who know it?

Or are you in this just to have some cause?
Do you like opposing authority to the point where what you oppose means little or not at all?
Does it make you feel good that you are part of some informal opposition and that there are others who feel like you who support your views?

Is the science just a secondary issue to you?

Will you simply find a new explanation for your position as soon as the old one is proved invalid without giving much thought to it?

Do you realize that all the nonsense you type can influence others opinions on this subject and prevent them from forming a realistic picture?

Do you realize you are spreading disinformation and actively promoting wrong facts just for your own personal gain?

Don't you see anything wrong with it?

Think about it for a moment.

Now, if you really believe what I stated disapproves IPCC's statements (as opposed to just trying to save face in a silly way), then explain where you think we are in conflict and I will try to clear it up for you.

(For those who don't know the context, I don't mind people being wrong but I do mind when someone proven wrong many times keeps spreading his nonsense)
Velanarris
2.2 / 5 (10) Dec 02, 2008
Do you realize that you either have to really learn the science or just leave the topic to others who know it?

Or are you in this just to have some cause?
Do you like opposing authority to the point where what you oppose means little or not at all?
Does it make you feel good that you are part of some informal opposition and that there are others who feel like you who support your views?

Is the science just a secondary issue to you?

Will you simply find a new explanation for your position as soon as the old one is proved invalid without giving much thought to it?

Do you realize that all the nonsense you type can influence others opinions on this subject and prevent them from forming a realistic picture?

Do you realize you are spreading disinformation and actively promoting wrong facts just for your own personal gain?

Don't you see anything wrong with it?

Think about it for a moment.
Take a look at your above statements and apply them to your heroes of the AGW movement.

Modernmystic
2 / 5 (12) Dec 02, 2008
LMFAO...SH you know you just said the same thing Vel did a couple of posts up?

Welcome to our side!
Velanarris
1.6 / 5 (7) Dec 03, 2008
Like I said SH, utterly priceless.
wookiemeister
5 / 5 (3) Dec 28, 2008
energy comes from the sun some 93 million miles away. the energy from the sun is split roughly half half between heat and visible light.

this energy falls on the planet's surface and atmosphere. the heat is absorbed mainly by water vapour, the carbon dioxide molecule and the other greenhouse gasses. thanks to the greenhouse gasses life on earth flourishes, without these gasses life would be much tougher (colder).

when HEAT hits the surface it warms the surface and emits heat back into the atmosphere heating it up. when heat hits the atmosphere it heats it up too whether its being emitted from the surface or directly from the sun.

when VISIBLE light hits the atmosphere some of it gets reflected back by things like white clouds and some gasses. when some visible light hits the surface some of it gets reflected back into space unchanged and so sails back into space without heating the atmosphere to any appreciable level - for example snow covered regions will be colder because visible light energy gets reflected back into space without heating the atmosphere. the whiteness of the snow fields reflects VISIBLE light energy back into space.

the VISIBLE light that gets absorbed by the surface and HEATS it (the colour black for example) and this heat is then radiated from the surface and so heats the atmosphere as carbon dioxide and water vapour absorb heat (NOT VISIBLE LIGHT about 50% of the sun's output).

areas where light is readily absorbed will be scorching this is why solar hot water heating does so well it absorbs most of the energy of the sun to heat water.

white paint imitates the snow fields by REFLECTING VISIBLE LIGHT energy and this light energy is sent back into space UNCHANGED and importantly by this energy remaining unchanged it doesn't get absorbed by greenhouse gasses and hence DOESN"T HEAT the atmosphere (creating problems such as over heating).

remember it is only HEAT/ INFRARED that is absorbed by the atmospehere in all practical terms NOT VISIBLE LIGHT.

white roofs will reflect a significant amount of the suns energy back into space without heating the atmosphere.

the properties of white paint mean that visible frequencies do not get turned into heat by absorption and the world gets cooler, we create a snowfield effect to turn the tide of global warming.

get painting