Can we control the temperature of Earth?

[Dimitri]

Due to the lengthy answers and numbers of pages here I must admit of not having read all the responses.

I would like to contribute here and comment on a few things I've already seen here.

To start with:
In various posts I see the mentioning of CO2 being emitted as the big reason of global warming. I would like to point out that most graphs which talk about CO2-emissions are not only about CO2 alone. When it comes to CO2-emission graphs it is not only an overview of the total CO2 being blown into the air by animals (I count humans as animals), plants, eruptions and other natural phenomena which cause CO2. Other greenhouse gasses such as CH4 (methane) and H2O are also being converted as a CO2-emission. (Converting towards CO2-emission now tends to be a basic to work with, don't ask me why, it's a general trend I have noticed in several files concerning global warming).

CO2 on the other hand is also one of the less dangerous ones. Greenhouse gas H2O is far more dangerous due to a feedback mechanism. It also is responsible for a contribution of 36-72% (in comparisation: CO2 has about 9-26%). I should also admit I cannot state an exact percentage of contribution from the gasses towards the greenhouse effect. There are various reasons such as the gasses emitting and absorbing heat at the same frequencies as other gasses. Although I think the given numbers are at average good enough.

On a personal note I would also raise the question and raise the doubt if it really is our fault/influence why the temperature is raising at "alarming" rate. From what I can guess, natural sources emitting greenhouse gasses have a bigger influence then me driving my car and the other steps taken to fabricate my car and other stuff we tend to work with. (Discussable and open for based sources to let me change my idea, preferably in a pm).

To continue:
Climate change is something very complex and people claiming they know the truth are probably selling woo. Climate change and global warming has different effects per region. As I have read in a post, Denmark and other more northern regions are dealing with a decline in permafrost and raise in temperatures. Up here in Belgium (and I can also say the Netherlands, parts of Germany, and parts of France) we noticed a decline in temperature during the winter seasons.
While it may get less colder in the more northern regions, the average temperature in more Southern regions during winter seasons has declined (the last 4-5 years we actually had snow and a pretty cold winter while the years before it was quite a bit warmer with temperatures between 2-12 degrees Celsius). Explanation here would have to do with the transatlantic gulf-stream. (Quite lengthy I'll have to ask to look it up for yourself).

The climate change has different effects, as mentioned before, per region. If my memory serves correct then Europe will end up in an Ice-age while other regions will have to deal with alarming temperature raises.
A last nuance which should be made would be that on the geological timescale the earth just ended a large ice-age. Global warming is therefor a fact. Influences by man on the other hand I find discussable.

Another effect I would like to toss in would be "Global dimming".
--> http://en.wikipedia.org/wiki/Global_dimming
It has caused to not having even higher temperatures during the summer-months.

 

[Pixel42]

Dimitri: some of what you say in your post is correct but there's a lot more that isn't. Can I suggest you begin by reading one of the better web resources on the subject, perhaps this free course (5 hours study) from the Open University:

http://openlearn.open.ac.uk/course/view.php?id=1526

 

[Dimitri]

Might I ask which parts? I'm not really in the mood of watching a 5hour lecture when I can simply shorten it towards minutes if a few statements I made were wrong.

 

[Reality Check]

Due to the lengthy answers and numbers of pages here I must admit of not having read all the responses.

I would like to contribute here and comment on a few things I've already seen here.

To start with:
In various posts I see the mentioning of CO2 being emitted as the big reason of global warming. I would like to point out that most graphs which talk about CO2-emissions are not only about CO2 alone. When it comes to CO2-emission graphs it is not only an overview of the total CO2 being blown into the air by animals (I count humans as animals), plants, eruptions and other natural phenomena which cause CO2. Other greenhouse gasses such as CH4 (methane) and H2O are also being converted as a CO2-emission. (Converting towards CO2-emission now tends to be a basic to work with, don't ask me why, it's a general trend I have noticed in several files concerning global warming).

So graphs of greenhouse gasses exist that plot the different gasses as CO2 equivalents? No problem there.
The minor nitpick that I have is that you state "most". There are many graphs are of CO2 only, e.g. actual measurements of CO2.

CO2 on the other hand is also one of the less dangerous ones. Greenhouse gas H2O is far more dangerous due to a feedback mechanism. It also is responsible for a contribution of 36-72% (in comparisation: CO2 has about 9-26%). I should also admit I cannot state an exact percentage of contribution from the gasses towards the greenhouse effect. There are various reasons such as the gasses emitting and absorbing heat at the same frequencies as other gasses. Although I think the given numbers are at average good enough.

CO2 is one of the more dangerous greenhouse gasses because there is a lot of it and it is a driver of changes in the other greenhouse gasses such as H2O.
From the Skeptical Science blog (I cite this a lot since the author has a commitment to backup his articles with published papers): CO2 is not the only driver of climate - it just has twice the radiative forcing of all the other greenhouse gases combined.

On a personal note I would also raise the question and raise the doubt if it really is our fault/influence why the temperature is raising at "alarming" rate. From what I can guess, natural sources emitting greenhouse gasses have a bigger influence then me driving my car and the other steps taken to fabricate my car and other stuff we tend to work with. (Discussable and open for based sources to let me change my idea, preferably in a pm).

You are right - your car has no measurable effect on global temperatures. A billion cars do.

To continue:
Climate change is something very complex and people claiming they know the truth are probably selling woo. Climate change and global warming has different effects per region. ...

That is correct. That is why the IPCC (for example) is very careful to state that AGW and its effects are not truths.
And climate change has different efffect in different regions. I am not sure what your point is though.

Another effect I would like to toss in would be "Global dimming".
--> http://en.wikipedia.org/wiki/Global_dimming
It has caused to not having even higher temperatures during the summer-months.

I think you are referring to the suggestion that global dimming masks some of the global warming. In that case the measurements that seem to show that the global dimming trend is reversed are worrying since that suggests even more global warming.

 

[lomiller]

Might I ask which parts? I'm not really in the mood of watching a 5hour lecture when I can simply shorten it towards minutes if a few statements I made were wrong.

You seem to have had some time for doing some reading, unfortunately you seem to have spent it in the wrong places as the points you bring up echo a number of reasonable sounding but completely anti-scientific points designed to hoodwink casual readers.

First:
Plants absorb CO2, store the carbon and release the oxygen. Animals eat the plants, combine it back with the Oxygen and breath it back out as CO2. This is a closed system that can't change the amount of CO2 in the atmosphere in the way digging up long dead plants and burning them does so adding these together and saying the fossil CO2 "only makes up a small part" is utterly dishonest.

Second:
Water vapor does indeed trap more heat then CO2, but it can't change the temperature of the earth. Wile CO2 persists in the atmosphere for centuries, and some part will be around for as much as 100 000 years if you release "extra" water vapor into the atmosphere it will be gone within a weak, so you can't increase the amount of heat being trapped by water vapor, at least not directly. (If you raise the air temperature by other means like releasing CO2, the air can hold more water and that additional water can trap more heat. this is called water vapor feedback)

third:
While no science is ever final this is distinctly different from saying "no one knows for sure". the fact is that the scientists studying this overwhelmingly agree on a number of facts, including: the planet is warming, this warming is caused primarily by human release of greenhouse gasses, this change will be 2-4.5 deg C for every doubling of CO2 in the atmosphere and that humans have increased the amount of CO2 in the atmosphere from ~280ppm in postindustrial time to ~395 ppm today.

 

[MRC_Hans]

Was the amount of clouds + heat reflection why the winter was so cold here and many places?
Or WHY suddenly so cold

Ehr, no. The cold winter was the reason for the many clouds and all the snow, not the other way around.

I will explain it to you on cow level:

We only get snow cover when it is cold.
If it is not cold, the snow will melt.
So it must be cold before we have a snow cover.
So the snow cover can't be the reason for the cold.

- Capisco?

Hans

 

[Pixel42]

Might I ask which parts?

These parts:

CO2 on the other hand is also one of the less dangerous ones. Greenhouse gas H2O is far more dangerous due to a feedback mechanism.

All warming, whatever its initial cause, causes positive feedbacks. Warmer air holds more water vapour, but warmer oceans hold less CO2 which gets outgassed into the atmosphere. Water vapour will eventually rain out whatever the temperature, but CO2 will accumulate.

From what I can guess, natural sources emitting greenhouse gasses have a bigger influence then me driving my car and the other steps taken to fabricate my car and other stuff we tend to work with.

As has been explained there's a CO2 biological (and indeed geological) cycle, and there's digging up carbon that has been sequestered for millions of years and adding it to the atmosphere. CO2 levels have varied between about 240 ppm (during glaciation) and about 300 ppm (during warmer inter-glacials) for millions of years. 150 years ago it was 280 ppm, which is what you'd expect towards of the end of an inter-glacial period. It's now 384 ppm.

The climate change has different effects, as mentioned before, per region. If my memory serves correct then Europe will end up in an Ice-age while other regions will have to deal with alarming temperature raises.

There's a possibility that the Gulf Stream will disappear, but it's currently considered small. Also Europe's climate is more influenced by the fact that it's next to a huge ocean than by any particular current in it. Regional variations will certainly occur, but by the end of the century they're more likely to be less than average warming in some places and more than average in others rather than some places actually getting significantly colder. The UK's climate, for example, is I believe predicted to warm by about half as much as the global average over the next century or so.

A last nuance which should be made would be that on the geological timescale the earth just ended a large ice-age.

This is simply wrong. We are currently about 6000 years past the mid point of a warmer inter-glacial period within a cycle of ice ages; had we not started burning fossil fuels we could have expected the world to gradually cool and the glaciers to advance again in a few tens of thousand years.

 

[Dimitri]

So graphs of greenhouse gasses exist that plot the different gasses as CO2 equivalents? No problem there.
The minor nitpick that I have is that you state "most". There are many graphs are of CO2 only, e.g. actual measurements of CO2.

Point taken, but what I was aiming at is the simple fact staring at CO2 alone is a problem. There are other gasses who are being released in even higher concentrations and whose probable influence on the heating is at average higher then CO2.

CO2 is one of the more dangerous greenhouse gasses because there is a lot of it and it is a driver of changes in the other greenhouse gasses such as H2O.
From the Skeptical Science blog (I cite this a lot since the author has a commitment to backup his articles with published papers): CO2 is not the only driver of climate - it just has twice the radiative forcing of all the other greenhouse gases combined.

While this may sound as a logical explanation and reasoning you are forgetting a few things here. H2O has a bigger heat capacity in comparisation with other greenhouse gasses. H2O is more likely to store bigger amounts of heat within the earths atmosphere. I would also doubt CO2 is more dangerous then H2O if I were to consider the amounts being released in the air. (How much of the earth is being covered by water again and how much of that surface evaporates per second?) . When talking about radiation force of the different gasses it is also best to take the number of concentrations next to it and start calculating what the real contribution is.

You are right - your car has no measurable effect on global temperatures. A billion cars do.

There you go again, cars...
I'd find it quite bothersome "cars" are being used as a scapegoat. They are not the only things which produce CO2 or are the only major factor towards contribution to global warming. Even so, the car-industry (at least in Europe) made huge contributions in reducing the gasses emitted from cars. Another important sector which needs to be taken on are industry (altough they already made contributions in reducing their emissions) and food-sector.
On the other hand there are continiuos natural sources who emit large amounts of greenhouse gasses. Simple evaporation of water above the oceans is considered one of these sources. Others would include vulcanism, swamps (CH4 and other gasses as a result from decomposing in absence of air),...
Taken these into account I would be inclined to think us humans are not contributing/influencing that a big deal. Maybe speeding it up a little but being the number 1 to blame.. doubtly.

Lomiller:

Plants absorb CO2, store the carbon and release the oxygen. Animals eat the plants, combine it back with the Oxygen and breath it back out as CO2. This is a closed system that can't change the amount of CO2 in the atmosphere in the way digging up long dead plants and burning them does so adding these together and saying the fossil CO2 "only makes up a small part" is utterly dishonest.

Might look flawless but ever considered how those "dead plants" managed to grow many years ago? Following your logic then the use of fossil CO2 is also a closed system. I'd prefer (and it would be more correct) if you said it was decomposed organic material instead of dead plants. Fossile fuel not only has its source from decomposed organic material but also likely from methane which was encrusted in the earths surface long before any plants or organic life was present. Taking this in mind will make the statement of fossil fuel being a contribution towards a raise of CO2 emission more likely to be true.

Water vapor does indeed trap more heat then CO2, but it can't change the temperature of the earth. Wile CO2 persists in the atmosphere for centuries, and some part will be around for as much as 100 000 years if you release "extra" water vapor into the atmosphere it will be gone within a weak, so you can't increase the amount of heat being trapped by water vapor, at least not directly. (If you raise the air temperature by other means like releasing CO2, the air can hold more water and that additional water can trap more heat. this is called water vapor feedback)

Water vapor feedback is a fact at the moment. And while you might be right about water being much less longer in the atmosphere then CO2 the feedback mechanism is not to be underestimated. Add up the concentrations of water being present in the atmosphere and the contribution of trapping heat will quite fastly outgrow those of CO2.

While no science is ever final this is distinctly different from saying "no one knows for sure". the fact is that the scientists studying this overwhelmingly agree on a number of facts, including: the planet is warming, this warming is caused primarily by human release of greenhouse gasses, this change will be 2-4.5 deg C for every doubling of CO2 in the atmosphere and that humans have increased the amount of CO2 in the atmosphere from ~280ppm in postindustrial time to ~395 ppm today.

While there is an agreement on certain statements, even more statements are being discussed heavily. Even the one I indicated in red (or at least should be nuanced).

While some of you make very valid points, I can see some information missing here and generalisations being made who are wrong in the greater scheme of things.
Oh btw:

You seem to have had some time for doing some reading, unfortunately you seem to have spent it in the wrong places as the points you bring up echo a number of reasonable sounding but completely anti-scientific points designed to hoodwink casual readers.

When it comes to global warming, politics have left their mark. Al Gore's "inconvenient truth" was a sort of publicity stunt for his political agenda. While I applaud for making the people aware of these things happening he could at least have used full scale graphs (and not parts) and contributing CORRECT information (there are a few fallacies).
Other marks would include the importance of money in the whole debate (why else has Copenhagen failed?). In Europe you can even "buy" fresh air from other countries if your national emissions tends to be too high for the European norms. My points may sound anti-scientific, yet the opposite is true. My guess would be you being used to the prechewed information available trough media. I'm more used with the IPCC (altough they are not 100% correct as opposed to what almost everyone thinks), VMM (Vlaamse Milieu Maatschappij), and other official European files with needed information on the given measurments.
But then again, I'm but a human and can make mistakes.

Did I already mentioned I am a bachelor in environmental science (milieuzorg in dutch) and my past studies before going to an higher education level already included subjects concerning global warming and the mechanics behind them? I can claim to be a climate scientist if I follow some of the logic some so-called skeptics tend to have..

 

[Dimitri]

All warming, whatever its initial cause, causes positive feedbacks. Warmer air holds more water vapour, but warmer oceans hold less CO2 which gets outgassed into the atmosphere. Water vapour will eventually rain out whatever the temperature, but CO2 will accumulate.

That's odd, from an article in 2007 the ocean tends to absorb more CO2 then previously thought.--> http://www.newscientist.com/article/dn11170

As has been explained there's a CO2 biological (and indeed geological) cycle, and there's digging up carbon that has been sequestered for millions of years and adding it to the atmosphere. CO2 levels have varied between about 240 ppm (during glaciation) and about 300 ppm (during warmer inter-glacials) for millions of years. 150 years ago it was 280 ppm, which is what you'd expect towards of the end of an inter-glacial period. It's now 384 ppm.

I prefer to take a longer timescale then a simple 150 years. On a large geological timescale with the evolution of CO2 concentrations it is easy to see we are at the moment at an exceptionally LOW period of carbon in the atmosphere. At a greater view the current raise we are having is almost natural. I'm not saying we don't have a hand in it, just saying for watching out what you claim. We might have an influence, but I suspect it is far lesser we would think it is.

This is simply wrong. We are currently about 6000 years past the mid point of a warmer inter-glacial period within a cycle of ice ages; had we not started burning fossil fuels we could have expected the world to gradually cool and the glaciers to advance again in a few tens of thousand years.

It is also known some ice-ages started AFTER the earth had endured a moment of global warming. http://www.guardian.co.uk/environment/2003/nov/13/comment.research
http://www.geocraft.com/WVFossils/ice_ages.html
It should also be noted when it comes down to graphs, the trends followed are hardly linear and in reality will always show variations. It is possible there is a raise of CO2 in the atmosphere for the forthcomming 20 years or so and suddenly decline once again. Same for temprature and other gasses. Please, do keep in mind the measurments have only started 150 or so years ago and that while we have some methods of getting an idea what happened in the past we still have to guess towards a certain extend?

 

[Pixel42]

That's odd, from an article in 2007 the ocean tends to absorb more CO2 then previously thought.--> http://www.newscientist.com/article/dn11170

The oceans are indeed currently absorbing a lot of the CO2 we're putting into the atmosphere (possibly as much as 40%), causing increased acidity which is a problem in its own right, but it cannot continue doing so indefinitely. Ice cores tell us that the CO2 atmospheric level starts to rise typically several centuries after the start of the forcing that initiated warming (e.g. the Milankovich cycles) - obviously there's a lot of water in the oceans, and it takes a long time for its average temperature to warm to the point where it begins to outgas. But we have more than enough evidence from ice cores and other sources to support the expectation that warmer oceans will eventually stop absorbing CO2 and start releasing it, starting a positive feedback to rival the water vapour one.

I prefer to take a longer timescale then a simple 150 years. On a large geological timescale with the evolution of CO2 concentrations it is easy to see we are at the moment at an exceptionally LOW period of carbon in the atmosphere. At a greater view the current raise we are having is almost natural.

It's certainly true that CO2 levels have been higher before, but over those timescales other factors (like continental drift) have to be taken into account. With a continent over one of the poles we expect to be in a cycle of ice ages with occasional warmer inter-glacials, with CO2 levels in the range 240 - 300 ppm, as we have been for several tens of millions of years. What natural process could cause the CO2 levels to rise by over 100 ppm in little more than a century? Plus isotropic analysis tells us it comes from fossil fuel.

I'm not saying we don't have a hand in it, just saying for watching out what you claim. We might have an influence, but I suspect it is far lesser we would think it is.

And your grounds for that suspicion are?

It is also known some ice-ages started AFTER the earth had endured a moment of global warming. http://www.guardian.co.uk/environment/2003/nov/13/comment.research
http://www.geocraft.com/WVFossils/ice_ages.html

Indeed. And the relevance to the current situation is?

Incidentally this discussion really belongs in the moderated global warming thread rather than the "what wacky idea has Bjarne come up with this time?" thread.

 

[Dimitri]

I'm gonna retreat here and follow from a distance..
Looks like there are a few things which I need to refresh and am ashamed of having forgotten them.

To answer a question:

And your grounds for that suspicion are?

The fact that the carbondioxide emitted by humans was about 1-5% of the total which is being emitted by all sources.
http://biocab.org/Total_Emisivity_CO2.html
http://www.geocraft.com/WVFossils/greenhouse_data.html

 

[Reality Check]

Point taken, but what I was aiming at is the simple fact staring at CO2 alone is a problem. There are other gasses who are being released in even higher concentrations and whose probable influence on the heating is at average higher then CO2.

There are other gasses who are being released in even higher concentrations and whose probable influence on the heating is at average less then CO2: CO2 is not the only driver of climate

While this may sound as a logical explanation and reasoning you are forgetting a few things here. ...

Ditto: CO2 is not the only driver of climate
But yes: Water vapor is the most powerful greenhouse gas

There you go again, cars...
I'd find it quite bothersome "cars" are being used as a scapegoat....

Not only cars (which you blamed, not me) - all fossil fuel burning releases CO2, e.g. coal fired power stations.

On the other hand there are continiuos natural sources who emit large amounts of greenhouse gasses.
...
Taken these into account I would be inclined to think us humans are not contributing/influencing that a big deal. Maybe speeding it up a little but being the number 1 to blame.. doubtly.

The problem is that climate scientists have measured that it is us humans that are contributing/influencing that a big deal, e.g.

• Are humans too insignificant to affect global climate?
• How do human CO2 emissions compare to natural CO2 emissions?

 

[Reality Check]

...
To answer a question:

The fact that the carbondioxide emitted by humans was about 1-5% of the total which is being emitted by all sources.
http://biocab.org/Total_Emisivity_CO2.html
http://www.geocraft.com/WVFossils/greenhouse_data.html

Actually neither link answers the question because neither stated that "carbondioxide emitted by humans was about 1-5% of the total which is being emitted by all sources".
The first does not mention human/natural CO2 emission at all.
It is a web page - not a published paper. It does have "This didactic article was Peer Reviewed by scientists of the University Regiomontana on June 28, 2010". The author is Nasif Nahle - Scientific Research Director at Biology Cabinet (a biologist?). It does not cite other climate papers - just text books.

The second link is just a web page and has Table 1 with human/natural additions = 11,880/68,520 or human additions are ~15% of the total CO2 addition to the baseline which is the important statistic IMO.
The web page is also rather old (2003).

 

[macdoc]

The fact that the carbondioxide emitted by humans was about 1-5% of the total which is being emitted by all sources.

I'd say a retreat IS in order and perhaps follow the links in my sig to a refresher course

It's the contribution of fossil carbon by humans to the natural carbon cycle where the problem arises, the subsequent amplification of that by water vapour.

Currently, there is little or no contribution from natural sources of fossil carbon. ( there has been in the past by way of extensive magma intrusions in carboniferous rocks - see Siberian traps and Deccan traps )

The carbon cycle is well understood and has been for more than a century.
catch up > read here http://www.aip.org/history/climate/summary.htm
tho we continue to greater understanding of the cycle interactions.

This is a decent analogy
http://dotearth.blogs.nytimes.com/2009/01/28/the-greenhouse-effect-and-the-bathtub-effect/

this is the heart of it...

Carbon dioxide from burning fuels and forests is flowing in twice as fast as it is being absorbed by plants and the ocean,
We have some buffers, cryosphere and hydrosphere that can mute some of the temperature transients from the atmosphere - but once in play - carbon is forever ( in human terms ) so each year builds on the last.
Unlike other short term but sometimes more powerful GHG ( methane for one, CFC other ) it does not come back to ground state completely for up to 100k years.

Nature Reports Climate Change
Published online: 20 November 2008 | doi:10.1038/climate.2008.122
Carbon is forever

Carbon dioxide emissions and their associated warming could linger for millennia, according to some climate scientists. Mason Inman looks at why the fallout from burning fossil fuels could last far longer than expected.

http://www.nature.com/climate/2008/0812/full/climate.2008.122.html

at least you are willing to re-assess your position...good on ya

The links below - some straightforward - others complex will at least get you the basics from the main stream climate science community.

 

[lomiller]

Might look flawless but ever considered how those "dead plants" managed to grow many years ago? Following your logic then the use of fossil CO2 is also a closed system. I'd prefer (and it would be more correct) if you said it was decomposed organic material instead of dead plants. Fossile fuel not only has its source from decomposed organic material but also likely from methane which was encrusted in the earths surface long before any plants or organic life was present. Taking this in mind will make the statement of fossil fuel being a contribution towards a raise of CO2 emission more likely to be true.

When these plants grew the earth had 5-10 times as much CO2 in the atmosphere, and was 10 deg warmer then today despite the fact the Sun was 10% cooler. Yes, over billions of years even fossil carbon is part of a closed system, but we are worried about timescales more relevant to humans. We have been on this planet for only a few hundred thousand years, geological changes over billions of years are not something we need to worry about, changes over a few decades are a great concern.

Water vapor feedback is a fact at the moment. And while you might be right about water being much less longer in the atmosphere then CO2 the feedback mechanism is not to be underestimated. Add up the concentrations of water being present in the atmosphere and the contribution of trapping heat will quite fastly outgrow those of CO2.

Positive feedback enhances the effect of forcing negative feedback diminishes the effect of forcing. In the absence of some persistent forcing nether has any impact on climate change. IOW water vapor can only amplify other forcing like CO2, it cannot cause climate change on it’s own.

Every major science organization endorses some form of that statement, surveys of the literature show that nearly all published papers implicitly or explicitly support this point and surveys of the scientists who actively publish papers on the earth climate show that they overwhelmingly agree on this point. In fact you will not find any significant dissenting opinion in any scientific source. If you have been reading dissent on that point the overwhelming probably is that you have been viewing political opinion rather then scientific sources.

Did I already mentioned I am a bachelor in environmental science (milieuzorg in dutch) and my past studies before going to an higher education level already included subjects concerning global warming and the mechanics behind them? I can claim to be a climate scientist if I follow some of the logic some so-called skeptics tend to have..

One of the most common sources of woo are people who some small amount of tangential knowledge and assume that qualifies them to dispute the entire body of rational scientific discourse. If you are not personally expert in an area the fact that you are taking a position in opposition to nearly all the published work should trigger major self examination.

When it comes to global warming, politics have left their mark. Al Gore's "inconvenient truth" was a sort of publicity stunt for his political agenda. While I applaud for making the people aware of these things happening he could at least have used full scale graphs (and not parts) and contributing CORRECT information (there are a few fallacies).
Other marks would include the importance of money in the whole debate (why else has Copenhagen failed?).

Gore’s film is not intended as an argument towards scientists, rather it is intended to inform the public of the state of the science. As such discussion of it really belongs more in the politics forums, however it’s worth pointing out theta it does quite a good job at accurately reflecting the current state of the science, certainly it’s far closer to the science then any of the attempts to attack it have been.

Here are some examples of what some real, actively publishing climate scientists have to say regarding it.

http://www.realclimate.org/index.php/archives/2006/05/al-gores-movie/

http://www.realclimate.org/index.php/archives/2007/10/convenient-untruths/

Overall, our verdict is that the 9 points are not “errors” at all (with possibly one unwise choice of tense on the island evacuation point). But behind each of these issues lies some fascinating, and in some cases worrying, scientific findings and we can only applaud the prospect that more classroom discussions of these subjects may occur because of this court case.

 

[lomiller]

The fact that the carbondioxide emitted by humans was about 1-5% of the total which is being emitted by all sources.

As pointed out above, this is a piece of misinformation being deliberately circulated for political reasons. It’s arrived at by treating new/sequestered CO2 release as identical to the back and forth exchange of CO2, which cannot change atmospheric levels.

Human release of CO2 is nearly 2.5 times the accumulation of CO2 in the atmosphere over the last 100 years. Furthermore this fossil CO2 has a distinct isotope signature, so it can be confirmed that 100% of the CO2 that has accumulated in the atmosphere over the last 100 years is of fossil origin. There is absolutely no question that humans are responsible for the increased CO2 levels, this has been “settled science” since the 1950’s.

 

[Trakar]

Good post(s)! hope you don't mind a few little tweaks?

When these plants grew the earth had 5-10 times as much CO2 in the atmosphere, and was 10 deg warmer then today despite the fact the Sun was 10% cooler. Yes, over billions of years even fossil carbon is part of a closed system, but we are worried about timescales more relevant to humans. We have been on this planet for only a few hundred thousand years, geological changes over billions of years are not something we need to worry about, changes over a few decades are a great concern.

should probably change "billions" to "hundreds of millions." I know its a bit awkward and I don't mean to be pedantic, but it's a whole lot closer to accurate.
(simple version: http://fossil.energy.gov/education/energylessons/coal/gen_howformed.html)

Positive feedback enhances the effect of forcing negative feedback diminishes the effect of forcing. In the absence of some persistent forcing nether has any impact on climate change. IOW water vapor can only amplify other forcing like CO2, it cannot cause climate change on it’s own.

excellent!

And others have already linked to very good references dealing with issues of persistence in the atmosphere and exactly why water vapor is (at least at the current range of Earthly conditions) considered a feedback effect rather than a forcing condition

Every major science organization endorses some form of that statement, surveys of the literature show that nearly all published papers implicitly or explicitly support this point and surveys of the scientists who actively publish papers on the earth climate show that they overwhelmingly agree on this point. In fact you will not find any significant dissenting opinion in any scientific source. If you have been reading dissent on that point the overwhelming probably is that you have been viewing political opinion rather then scientific sources.

not that relevent, qualified concensus is the end all arbiter of reality, but this level of agreement both within the specifically relevent fields of study AND across the broader spectrum of scientific understandings is extremely rare for any issue. Definitely worth Bolding, IMO!

One of the most common sources of woo are people who some small amount of tangential knowledge and assume that qualifies them to dispute the entire body of rational scientific discourse. If you are not personally expert in an area the fact that you are taking a position in opposition to nearly all the published work should trigger major self examination.

of interest, especially among those who claim or hold a rigorous scientific or skeptical/critical analysis perspective of the world. If you look at the mainstream scientific literature and the positions of the leading scientific organizations around the planet you have to acknowledge the level of understanding and expertise or find some compelling reason why so many experts are so drastically mistaken.

Back when I first became interested in the subject (early 90's) there were a lot more ambiguities in understanding and a lot less concensus about many aspects of the phenomena, and I actually came to the subject with the intent and goal of debunking and discrediting what I thought were probably exaggerations and a "woo-ification" of the science. This was because there actually were a series of such arguments back in the mid-sixties through the mid-seventies, relating how runaway CO2 emissions were going to turn the Earth into an unihabitable hothouse. Of course, this was tied to UFOs and secret government treaties with aliens who were actually here to warn us about the impending destruction of our planet, while helping us to prepare shelters or escape craft so that a select few could survive the destruction. I spent a lot of time debunking and arguing against such foolishness back then, and was fairly sure that this more modern incarnation was merely a revamping of those arguments when I first started paying attention to them around the time of the '92 elections. Political baises probably influenced my initial take as well as by then I had been a registered Republican for the first 20 years of my voting life (first national election I voted in was Nov. of '68) and prominent Democrats were just starting to rally to the climate-change argument. Despite all this, and even though the science was much less certain and compelling than it currently is, the science that did exist was strongly supportive of the basic concepts and principles regarding Anthropogenic Global Warming. - well, not sure what that was, but it wasn't a "tweak" of your statements!

I think I'll leave it there for now, but once again, well done!!

 

[macdoc]

Originally Posted by Dimitri


Water vapor feedback is a fact at the moment. And while you might be right about water being much less longer in the atmosphere then CO2 the feedback mechanism is not to be underestimated. Add up the concentrations of water being present in the atmosphere and the contribution of trapping heat will quite fastly outgrow those of CO2.

No - Co2 is the forcing, water vapour is the feedback that magnifies the forcing.

So in that regard water vapour traps more heat than the C02 itself but they go in lockstep.

1 unit C02 warming results in about 1.6 in water vapour amplification. ( if I recall - too lazy to look it up _
No driver, no feedback/amplification.

This works in both directions..reduced C02 spirals to cooler temps along with the same reduction level due to reduced water vapour.
CO2 is the controlling mechanism in this case.

C02 can be a feedback itself in orbital changes....lower radiation incoming, cooler oceans, uptake more C02 and around it goes.

 

[lomiller]

Good post(s)! hope you don't mind a few little tweaks?



should probably change "billions" to "hundreds of millions." I know its a bit awkward and I don't mean to be pedantic, but it's a whole lot closer to accurate.
(simple version: http://fossil.energy.gov/education/energylessons/coal/gen_howformed.html)

Billions of years was a reference to how long it would take for that carbon to naturally return to circulation if we were not digging it up, not how long it’s already been buried for. I guess I could have been clearer.

 

[macdoc]

That's incorrect AFAIK....general assessment is 100k years on the outside based on the weathering uptake.