Attribution: Blowing in the WInd

By: Dr. Ricky Rood , 4:33 PM GMT on June 27, 2008

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Attribution (5)

This is the fifth in a series on the attribution of climate change; that is, how do we determine to what extent the observed warming is caused by humans? The earlier entries are cataloged at the end. (This one should, perhaps be the first!)

First a return to basics: I received a good letter from a reader about the difficulty of determining trends and attribution from, primarily, the last 150 years of observations. The challenge seems even more daunting with the observational evidence from the distant past of a cycle between ice ages and temperate periods. One of the reasons that we can predict with confidence that the globe will warm is the large, observed increase in carbon dioxide. Carbon dioxide warms the planet; this has been known since about 1800. The warming comes from carbon dioxide holding infrared radiation, heat, near the surface of the Earth. The quantitative physical description of this process is simple and well known.

Carbon dioxide, therefore, is different than in the past. It is much larger. It can “force” the temperature to be warmer. (Old, yet relevant, blog) It is the fact that we have this carbon dioxide forcing that we can both make confident predictions and look for signals of attribution. I have been trying to think of a good metaphor to describe forcing, that also maintains some relevance to climate change. (Help?) Here is one that I pose. Imagine that you have a small bell hanging on a string from a beam on your porch. If there is wind, then it will blow the bell and it will ring. If there is more wind, then the bell will ring with different characteristics, perhaps louder, more frequently, more erratically. You could designate the wind as “forcing” the bell by blowing it around. Call this the “natural forcing.” If you were compelled to science you could keep a record of wind speed and direction (perhaps other variables) and a record of the characteristics of the bell ringing.

Now imagine that you keep a small mallet on the porch, and that you hit the bell. This is “anthropogenic forcing.” (Let’s see: human-caused, manmade, womanmade --- isn’t it interesting that manmade is a “word,” and “womanmade” is not?) Hitting the bell, a new type of forcing, will have a distinctly different sound. There will be a sharp sound, followed by a ringing of the bell’s body, and then, in the end, because the hit will cause the bell the swing on the string, it will sound much like it was blowing in the wind. There are a set of characteristics of the ringing from hitting the bell that are distinctly different than the ring from blowing in the wind.

It is the difference in the characteristics of the bell blowing in the wind (“natural”) and the bell hit by the mallet (“anthropogenic”) that allow the definition of a “fingerprint.” This fingerprint can be used to determine whether the bell has been hit – or not?

When we look at atmospheric observations and measure that it is warming up, we are faced with a far more complex problem than a bell dangling from the porch in the wind. Still, though, the basic ideas are the same. We have a known anthropogenic forcing agent, the carbon dioxide (plus others!), and we have a set of fingerprints. Examples of the fingerprints include greater surface heating at the North Pole than at middle latitudes and at the South Pole. The complexity and importance of the climate problem requires that we identify a thorough set of fingerprints. These include the spatial and temporal structure of changes at the Earth’s surface, changes in the vertical temperature structure of the atmosphere, changes in the vertical temperature structure of the ocean, changes in ecosystems, and the list goes on.

One path to attribution of warming to human activity is to identify enough characteristics of the fingerprint to make a convincing determination. Imagine that you generate a long list of attributes of the fingerprint of climate change and some you find in the observations and some you do not find. Because you find one does not prove human-caused climate change. Because you do NOT find one does NOT disprove human caused climate change. One is faced with the analysis of a complex, varying system and the determination of uncertainties.

The figure below from Ben Santer at Lawrence Livermore National Laboratory is a summary picture of the variables in which human-caused signals of climate change have been identified. This is from a lecture in my class in 2008, and the entire lecture is here.

Figure 1. Taken from class lecture by Ben Santer. This figure is a summary of geophysical parameters in which fingerprints of human-caused climate change have been found.

WU blogs on Attribution of Climate Change to Human Activities:

WU Blog on Models and Attribution

Attribution (1)

Attribution (2)

Attribution (3)

Attribution (4)

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415. streamtracker
3:48 PM GMT on July 05, 2008
#413 StSimons,

Hansen did make that statement and while I do believe some Oil Co. are involved in funding a disinformation campaign, I do not believe it would help solve the problem of AGW to try them for it. I think it better to just counter disinformation with sound scientific information. Hansen is obviously frustrated since his work has been in the cross hairs of the disinformation campaign.

Are Big Oil and Big Coal Climate Criminals?

I prefer to focus on Hansen's scientific achievements and his well thought out policy prescriptions.

Unlike the conspiratorial theories regarding the IPCC, there is actual evidence to support the charge that Oil Co. have been involved in a disinformation campaign.

A new report from the Union of Concerned Scientists offers the most comprehensive documentation to date of how ExxonMobil has adopted the tobacco industry's disinformation tactics, as well as some of the same organizations and personnel, to cloud the scientific understanding of climate change and delay action on the issue. According to the report, ExxonMobil has funneled nearly $16 million between 1998 and 2005 to a network of 43 advocacy organizations that seek to confuse the public on global warming science.

This campaign is what has Hansen pissed off.
Member Since: October 24, 2005 Posts: 12 Comments: 1731
414. streamtracker
3:28 PM GMT on July 05, 2008

No, I think it would be waste of time to try Oil company executives and it one of the few disagreements I have with Hansen. I think that people should continue to document the link between the Oil Co. and dissemination of disinformation on AGW. Like the cigarette Co. who did the same, history will not judge them kindly for politicizing and distorting science. I can understand Hansen's frustration though, since his work has been a target of their misinformation campaigns.

It it too bad he made that comment, because it distracts form the large body of scientific work he has done. It's just fodder for denialists to distract from the science. I think his presentation at the G8 will help refocus the media on his considerable contributions as a scientist and currently as a leader in AGW mitigation policy.

But, I find it rather hilarious that you agree with the bolded statement.

Could it be that we don't know enough about the negative impacts of ocean fertilization? And maybe we should wait to implement it until we have done more research on its affects both positive and negative? Here's a quote from a scientist who has conducted fertilization experiments (he gets funded to test the idea)

"We already know that adding iron to the ocean usually alters the species composition of the phytoplankton community," Strutton said, "and it seems likely this would occur as a result of commercial applications. What if, instead of a beneficial species of phytoplankton, the fertilization inadvertently caused toxic diatoms like Pseudonitzschia to flourish?"


'There are too many scientific uncertainties relating both to the efficacy of ocean fertilization and its possible environmental side effects that need to be resolved before even larger experiments should be considered, let alone the process commercialized,' Rayfuse says. 'All States have an obligation to protect and preserve the marine environment and to ensure that all activities carried out under their jurisdiction and control, including marine scientific research and commercial ocean fertilization activities do not cause pollution.

But, oh no says Dirck Hartmann, they didn't advocate ocean fertilization because it wouldn't hurt the US. What utter conspiratorial nonsense.

You seriously believe that the IPCC is power hungry and wants to do things that hurt the US? You seriously believe that the yardstick the IPCC uses to determine what is a reasonable mitigation strategy has to do with whether or not it hurts the US?

So what is your evidence for this conspiracy? Do you have memo or emails from IPCC members that suggest a coordinated campaign to hurt the US and increase thier power.

Have you even read the IPCC 4th report? I doubt it, because if you did you would see that their policy prescriptions have a strong focus on technological innovation to help solve the climate crisis. Rather than hurting the US, if the US invested in that kind of innovation we could be a global leader and benefit economically as a provider of solutions.

Member Since: October 24, 2005 Posts: 12 Comments: 1731
411. sebastianjer
2:27 PM GMT on July 05, 2008
re 409

Actually Tracker the part you highlighted I basically do agree with. Do you agree with James Hansen's that oil company executive should be tried?
Member Since: August 26, 2005 Posts: 1030 Comments: 11197
410. streamtracker
1:11 PM GMT on July 05, 2008
#405 Thanks Mike.
Member Since: October 24, 2005 Posts: 12 Comments: 1731
409. streamtracker
1:10 PM GMT on July 05, 2008

I do not believe that there is another scientific issue, that has been so clearly defined by political ideologies. If the science of AGW is so clearly evident, how could this be? Politically I am an Independent and consider myself a moderate, however I notice that many scientist, though not all, of the skeptic camp seem to be conservative whereas most, though not all, of the AGW proponents seem to be politically Liberal. If the issue of AGW was indeed based upon scientific arguments, this political division would not be so obviously apparent.

Your logic escapes me? Because politicians and pundits have politicized AGW, that is evidence that the science is not sound? That kind of thinking fails some very basics of logical argumentation. Why not look at the weight of the scientific evidence instead of at the political affiliation of the opponents/proponents.

And where do you get your evidence for the political affiliation of scientists? Did you know that Hansen has voted for Republican's in past presidential races?

Political inclinations should have no impact on science analyses, but
in any case the above description of my inclinations is inaccurate. I can be accurately described as
moderately conservative. I am registered to vote (in Pennsylvania) as an Independent.
(Source: J. Hansen. 2006. Statement of Political Inclinations)

And if you don't support the writing of the writers that you post, then disavow their politicizing rhetoric. Otherwise all we can assume is that you support their writing.

So, the most recent post (402) you linked to contains these statements:

To increase the rate at which photosynthesis removes carbon dioxide from the atmosphere, a respected scientist proposed to the United Nations Intergovernmental Panel on Climate Change, or IPCC, seeding the ocean to trigger algae blooms. This practical, inexpensive, highly effective means for sequestering carbon dioxide would benefit the food chain in the oceans and increase fish populations. But because it did not impose hardships, require trading carbon credits, punish the U.S. or any other nation, or require increased governmental control, the IPCC rejected it. The IPCC uses the hoax of man made global warming to increase its power and that of a corrupt, anti-American United Nations that has proven itself impotent in combating world wide acts of terrorism, genocide in Sudan, the real threat of nuclear proliferation in the mid-east from Iran and Syria, or human rights violations in China and Africa.


People on the left claim global warming is real, a threat to the continued existence of mankind, and the debate as to its cause is over! Although none of this is true, it nevertheless is what four of my grandchildren were taught in high school. Most politicians on the left have little respect for truth and no regard for clarity, and apparently many high school teachers reflect their views.

Do you support that nonsense or not?
Member Since: October 24, 2005 Posts: 12 Comments: 1731
408. streamtracker
12:33 PM GMT on July 05, 2008

What a bunch of nonsense. The author may have worked on projects for NASA, but the doesn't even have a simple grasp of how the global climate system works. His desert versus tropics analogy made me laugh.

He completely conflated an example having to do with local short scale variability with a long term global trend.
Member Since: October 24, 2005 Posts: 12 Comments: 1731
407. cyclonebuster
12:19 PM GMT on July 05, 2008
Any idea why we are coming out of the La Nina so abruptly?

Sure not enough North Arctic ice to keep it cool anymore. It warms up quicker.
Member Since: January 2, 2006 Posts: 127 Comments: 20476
403. quasigeostropic
4:21 AM GMT on July 05, 2008

First off don't post things that I did not say and imply that I did.

That wouldn't be a first....He's done that exact same thing to me frequently...That sort of immaturity is the norm on here...I think its a waste of time coming on here to post...

Notice they dont come to your blog but only post in here...At least us "skeptics" have the guts to come into an AGW proponent's blog...
Member Since: November 20, 2007 Posts: 21 Comments: 192
402. sebastianjer
4:17 AM GMT on July 05, 2008
Alleviate world hunger produce more clean carbon dioxide

(Editor’s Note: To many in the know, Dirck T. Hartmann, who worked on the Apollo Space Program and many other significant NASA projects, was a fighter pilot in WWII, flying P38s. So when this gifted scientist/engineer/physicist and 87-year-old hero felt compelled to answer the questions of Man Made Global Warming, not only his son and grandchildren knew he had something to say with factual substance, truth and knowledge. What he has to say is clear and concise and should be read by everyone.)

What is your carbon footprint? That is the wrong question to ask. A more meaningful question is--How much carbon dioxide does it take to grow the wheat required to produce a loaf of bread? Or--How much carbon dioxide does it take to grow the corn for the chicken feed required to produce a dozen eggs?

Far from being a pollutant, man along with every animal on land, fish in the sea, and bird in the air is totally dependent on atmospheric carbon dioxide for his food supply.

Some politicians complain that the United States with only 3% of the world population uses 25% of the energy. But the clean carbon dioxide which we produce is increasing food production everywhere on earth. China, on the other hand, is building new power plants at a record rate using the abundant domestic supply of coal they have and has now passed the United States as the leading producer of carbon dioxide. Although their coal has a high sulfur content, they are building the new plants without any pollution controls. The sulfur dioxide which these power plants are releasing to the atmosphere, besides smelling like rotten eggs is, in sunlight, readily converted to sulfur trioxide, the highly solublegas responsible for most acid rain.

Photosynthesis is the process by which plants, using energy from sunlight, convert carbon dioxide and water into high energy fuels. It is responsible for all the fuel that feeds forest fires, and for the rapid grow-back of fuel after a fire. But even with the hundreds of millions of tons of coal and the billions of barrels of oil and gasoline that are burned annually, the carbon dioxide content of the atmosphere remains about .04%.

It has been estimated that more than two hundred billion tons of atmospheric carbon are fixed yearly by photosynthesis, 10%to 20% by land plants, and the remaining 80%to 90% by plant plankton and algae in the ocean, which constantly resupply us with oxygen. Atmospheric carbon dioxide acts like a thermostat for plant growth, increases triggering vast blooms of ocean algae, and spurts in the rate of growth of land plants. As long as man burns coal and oil responsibly, that is with pollution controls that minimize the production of acid rain, the earth can never have too much carbon dioxide. The plants will not permit it.

Anyone who has lived in a desert area where the relative humidity is frequently below 5%, knows that dry air is a lousy green house gas. It can be 115 degrees F (46 degrees C) during the day yet cool off so rapidly that a sweater is needed two or three hours after sunset. Despite the heat sink of the ground with rocks hot enough to fry an egg, the heat is radiated rapidly away through the dry air to the clear night sky. Since dry desert air has about the same .04% concentration of carbon dioxide as air everywhere else, it is not credible to conclude that carbon dioxide is causing global warming.

Water vapor is the most effective greenhouse gas by far. With high humidity, even without cloud cover, the night air cools at a rate so slow as to be nearly imperceptible, particularly if you are trying to sleep without air conditioning.

High humidity is the reason nights are so balmy in the tropics. At 100 degrees F and 100% relative humidity, water vapor accounts for only 2% of the atmosphere. It has a greater effect than all other greenhouse gases combined but, since it cannot be regulated, is rarely mentioned as a greenhouse gas.

If human activity is not the cause, why are the ice sheets on the earth poles receding? They are melting for the same reason that the polar caps on Mars are melting. For the 200 years or so that a record of sun spot activity has been kept, it has been observed that global temperatures on earth correlate closely with sun spot activity,very low activity corresponding to a mini ice age, and high activity to global warming.

Every second the sun converts 564 million tons of hydrogen into 560 million tons of helium, consuming its mass at the rate of 4 million tons per second. It has been doing this for 4.5 billion years and has about 4.5 billion years to go before all its hydrogen is used up. At that time it will have consumed less than 1% of its mass. This enormous solar furnace is responsible for climate change as well as all weather on earth....

Entire Article
Member Since: August 26, 2005 Posts: 1030 Comments: 11197
401. sebastianjer
4:11 AM GMT on July 05, 2008
Re 391


First off don't post things that I did not say and imply that I did. That was a quote by a atmospheric scientist not me. The only reason I posted it was because JFL had posted that particular scientist was not a skeptic of AGW so I posted a letter that he had sent expressing his opinions.

You quote and refer to James Hansen who recently said company executives should be tried as criminals for crimes against humanity. Some, particularly oil executives might find that offensive :)
What I find interestingly about the discussion is that you say that the science behind AGW is not Political. However not only do polls show that a majority conservatives and Republicans see the issue one way while a majority of Liberals and Democrats see it another way.
If the issue is scientifically beyond question, why the political divide, not only among the general population but among scientist themselves?

I do not believe that there is another scientific issue, that has been so clearly defined by political ideologies. If the science of AGW is so clearly evident, how could this be? Politically I am an Independent and consider myself a moderate, however I notice that many scientist, though not all, of the skeptic camp seem to be conservative whereas most, though not all, of the AGW proponents seem to be politically Liberal. If the issue of AGW was indeed based upon scientific arguments, this political division would not be so obviously apparent.

You decry accusations of scientific bias when they are aimed at proponents of AGW, yet see no problem when the motivations of opponents to AGW are slung around. What are the motivations of scientist that oppose AGW alarmism? You are constantly posting snide sarcastic remarks about conspiracy theories when they are leveled at AGW proponents, yet what then is the conspiracy of opponents to resist the "consensus". Certainly it can not be to win the favor of their peers or for advancement in their chosen field, since for the most part they are ridiculed for their stance. The old "bought out by fossil fuel interest" can no longer hold weight since the numbers of skeptics and their known backgrounds eliminate this accusation from being seriously considered for the vast majority.

I would submit, that only very small number of scientist would actually oppose, for financial or idealogical reasons, overwhelming evidence of a serious global catastrophe in the making. Yet we have growing numbers who have openly and vocally opposed this very proposal; for what purpose? You can attempt to disregard the growing numbers, by passing them off as misinformed, ignorant, bought off, or whatever, but the fact remains these skeptical scientist do exist in very large numbers. I guess they do not care about their kids and grandkids futures, less alone the very fate of mankind and the planet.
Member Since: August 26, 2005 Posts: 1030 Comments: 11197
400. streamtracker
2:36 AM GMT on July 05, 2008
#396 J,

That's good news that Hansen is talking at the G8. I hope they listen carefully to his message.

He has posted a copy of his letter to the Prime Minister of Japan as a pdf here.

It's the most data rich letter I have ever seen.

He has even made a call for fourth generation nuclear power generation investments.

Member Since: October 24, 2005 Posts: 12 Comments: 1731
399. cyclonebuster
1:35 AM GMT on July 05, 2008
Booming demand for flat-screen televisions could have a greater impact on global warming than the world's largest coal-fired power stations, scientists warn.

A greenhouse gas called nitrogen trifluoride, used to make the TVs, is 17,000 times more potent than carbon dioxide, said Michael Prather, director of the environment institute at the University of California, Irvine.

But no one yet knows how much of it is being released into the atmosphere by industry, a report in Britain's The Guardian said.

Prather's research shows production of the gas, which remains in the atmosphere for 550

Member Since: January 2, 2006 Posts: 127 Comments: 20476
398. cyclonebuster
12:10 AM GMT on July 05, 2008
Ocean Energy Resources
The ocean is a source of two significant sustainable forms of energy: thermal energy associated with the sun's heat absorbed by the ocean, and mechanical energy associated with the waves, currents and tides. Since the oceans cover more than 71% of the earth's surface, these forms of energy represent the largest solar collectors and retainers of the sun's vast energy that reach the earth's surface. By harnessing a fraction of one percent of ocean thermal energy, the world's energy needs can be met. Many of the steady ocean currents are highly energetic and provide tremendous potential for electric power generation - some are five times as energy-dense as the world's best wind power-generating sites.

Member Since: January 2, 2006 Posts: 127 Comments: 20476
397. cyclonebuster
11:57 PM GMT on July 04, 2008
Exploding Asteroid Theory Strengthened By New Evidence Located In Ohio, Indiana
ScienceDaily (July 3, 2008) — Geological evidence found in Ohio and Indiana in recent weeks is strengthening the case to attribute what happened 12,900 years ago in North America -- when the end of the last Ice Age unexpectedly turned into a phase of extinction for animals and humans – to a cataclysmic comet or asteroid explosion over top of Canada.
Member Since: January 2, 2006 Posts: 127 Comments: 20476
395. streamtracker
6:00 PM GMT on July 04, 2008
#394 Mike, take a look at the slope of the MEI for the current transition. It is notably steeper for a longer period of time than the other historical events.

Any idea why we are coming out of the La Nina so abruptly?
Member Since: October 24, 2005 Posts: 12 Comments: 1731
393. streamtracker
4:19 PM GMT on July 04, 2008
The current issues of Science has an interesting article on Greenland Ice Sheet dynamics and there are some aspects of the paper that are likely to create some confusion.

Large and Rapid Melt-Induced Velocity Changes in the Ablation Zone of the Greenland Ice Sheet
R. S. W. van de Wal,* W. Boot, M. R. van den Broeke, C. J. P. P. Smeets, C. H. Reijmer, J. J. A. Donker, J. Oerlemans.
Science 4 July 2008:
Vol. 321. no. 5885, pp. 111 - 113

Continuous Global Positioning System observations reveal rapid and large ice velocity fluctuations in the western ablation zone of the Greenland Ice Sheet. Within days, ice velocity reacts to increased meltwater production and increases by a factor of 4. Such a response is much stronger and much faster than previously reported. Over a longer period of 17 years, annual ice velocities have decreased slightly, which suggests that the englacial hydraulic system adjusts constantly to the variable meltwater input, which results in a more or less constant ice flux over the years. The positive-feedback mechanism between melt rate and ice velocity appears to be a seasonal process that may have only a limited effect on the response of the ice sheet to climate warming over the next decades.

What is already garnering the most media attention is the observation that the increase in ice sheet velocity is currently only a seasonal phenomenon. Some previous studies had suggested that melting surface water would lubricate the ice sheet and accelerate its ablation year-round and perhaps lead to a catastrophic collapse.

So, this could be good news. But only if conditions remain as they did during the 17 years of this study and if the study location is representative of dynamics throughout the ice sheet.

A few things seem to have already been lost in the reporting on this paper.

1) Even without the accelerated lose due to lubrication there is great concern about rise in sea level caused by the steady melting of the Greenland ice sheet. The IPCC sea level projections do not include the tipping point scenario that this new paper discounts. So, it changes nothing regarding those projections.

2) This paper does not say the ice sheet is growing. On the contrary, it reports that the rate at which the ice sheet is losing mass has steadily increased, but it's not due to velocity changes triggered by surface water melt.

3) Finally, the paper is based on data from a time period before the predicted rapid decreases in the Arctic sea ice extent. As the sea ice extent decreases the regional temperatures will increase significantly. This paper says nothing about how an increase in regional temperatures would effect the process of Greenland ice sheet lubrication.

The authors of the paper make the following precautionary comment:

The authors and independent experts familiar with the research stressed that the findings did not preclude the possibility that more widespread surface melting could eventually destabilize big areas of Greenland, the world's second largest ice storehouse. (Source second link below)

I am ready to take bets that denailists will now point to this paper and falsely claim that we have nothing to worry about when it comes to melting Greenland ice sheet. Despite the fact that the lose of the ice sheet is accelerating.

You can find a discussion of this paper here and here.
Member Since: October 24, 2005 Posts: 12 Comments: 1731
391. streamtracker
2:44 PM GMT on July 04, 2008

I never said it was a lefty plot, feeling guilty:).

Jer, If you don't believe it's a lefty plot then why do you keep posting diatribes by folks that do?

Here's what you posted in comment #208:
Make no mistake about it, "global warming" is a political instrument of the left wing. It's the favorite scare tactic of environmentalists.

Not the first time you've posted such opinions. Is it just because you like their prose?

I am perfectly comfortable in my political skin. You keep brining up the idea of guilt. Are you feeling guilty for posting such trash?

Member Since: October 24, 2005 Posts: 12 Comments: 1731
390. sebastianjer
1:18 PM GMT on July 04, 2008
RE 385

I never said it was a lefty plot, feeling guilty:). I don't own a truck, my vehicles probably emit less CO2 than yours, I very much believe in protecting the environment. I just do not believe that CO2 is that big of a concern. There are many reasons to begin reducing fossil fuel use CO2 emissions are not one of them IMO.

It really is irrelevant because as I stated the atmosphere will probably exceed 450ppm of CO2 because the reductions necessary to achieve that are not possible. Just based on the world's population growth, it is not going to happen.
Member Since: August 26, 2005 Posts: 1030 Comments: 11197
389. cyclonebuster
12:59 PM GMT on July 04, 2008
If man had the technology to weaken a major hurricane prior to landfall do you think we should use that technology to do so?

Member Since: January 2, 2006 Posts: 127 Comments: 20476
388. robodave
12:57 PM GMT on July 04, 2008
Someone earlier said that co2 is beneficial and radioactivity is destructive.

Radioactivity is supposedly needed for evolution. At high doses it's destructive. In low doses it aids cell mutation which can be beneficial over billions of years because nature sifts through these changes and selects the ones that aid our survival. At least, that is what the book says. In fact, radioactivity is very common and our own body emits it through c14 and potassium-40. Background radiation (natural) accounts for about 75% of our exposure. Btw, coal power happens to produce more radioactivity than nuclear power plants. That was surprising for me when I first read it.

Anyway, the point is that radioactivity in low doses isn't such a bad thing, but in large doses it overwhelms our body's ability to repair damaging changes.

Lastly, food and water (potassium) account for more exposure than coal power (plus) nuclear power (plus) nuclear weapon fallout. Why aren't the environmentalists trying to protect us from our own food/water??? Lol. We also have to keep in mind that this is probably a running average for every point on earth. If you were to sit yourself at the bottom of a nuclear test site from 40 years ago, I'm willing to bet that your exposure would be more significant - though still very low quantitatively.

This is what high doses are capable of:
Hiroshima survivors speak
Member Since: August 9, 2007 Posts: 1 Comments: 147
387. quasigeostropic
5:06 AM GMT on July 04, 2008
steamtracker cant even answer questions...But he SURE DOES have many of them...

AGW sounds as stupid as this statement:
If a long trend of global warming is occurring, there are two ways it could be related to humans. First, humans might be causing the warming. Second, global warming might be causing the humans.
Member Since: November 20, 2007 Posts: 21 Comments: 192
386. streamtracker
5:06 AM GMT on July 04, 2008
Would you like to destroy all those that expel CO2 in the process of breathing?

With a bit of simplification here's a comparison.

1) Plants take CO2 from atmosphere and make carbohydrates
2) Animals eat plants and expel CO2
3) Go to 1).

(Plants expel some CO2 to, but less than they take in. Globally less than half.)

And because transfer of energy from one trophic level to the next can not be more than about 10% efficient, it takes at least 10 times as much plant weight to build the same amount of animal weight.

So, no net increase of CO2 in atmosphere as a result.

It's part of a cycle.


1) Humans dig up fossil fuels
2) Humans burn fossil fuels and release CO2.
3) Natural systems absorbs some but not all of the CO2 we emit from burning fossil fuels.
4) CO2 concentration in atmosphere increases
5) Go to 1)

Controlling one of these processes is relevant to discussion of climate change. The other is not.

Study the carbon cycle.
Member Since: October 24, 2005 Posts: 12 Comments: 1731
385. streamtracker
4:33 AM GMT on July 04, 2008
#383 Yeah tuff guy - bring it on!!

The fact is that we are going there whether you like it or not, so better get ready for it.

And what exactly should I get ready for? I thought you didn't think it would have an affect. I thought you thought it was a lefty plot to take away your truck?
Member Since: October 24, 2005 Posts: 12 Comments: 1731
384. streamtracker
4:32 AM GMT on July 04, 2008
#381 What a bunch of irrelevant questions intended to cast doubt.

Is CO2 a natural element or not?

Is cyanide a naturally occurring compound or not? Yes.

Is CO2 necessary for life on this planet or not? Do we exhale Co2 or not? Do plants breathe CO2 or not?

Of course the answer to all those questions are "yes".

So let me ask an irrelevant question.

What would a 5, 10, 15 percent level of CO2 do to organisms living in it? No big deal CO2 is life giving right? But it gets to be bit a toxic at not so very high concentrations.

At what concentration does that wonderful CO2 we all exhale become a problem for people?

Not very much!

* At 1% concentration of carbon dioxide CO2 (10,000 parts per million or ppm) and under continuous exposure at that level, such as in an auditorium filled with occupants and poor fresh air ventilation, some occupants are likely to feel drowsy.
* The concentration of carbon dioxide must be over about 2% (20,000 ppm) before most people are aware of its presence unless the odor of an associated material (auto exhaust or fermenting yeast, for instance) is present at lower concentrations.
* Above 2%, carbon dioxide may cause a feeling of heaviness in the chest and/or more frequent and deeper respirations.
* If exposure continues at that level for several hours, minimal "acidosis" (an acid condition of the blood) may occur but more frequently is absent.
* Breathing rate doubles at 3% CO2 and is four times the normal rate at 5% CO2.
* Toxic levels of carbon dioxide: at levels above 5%, concentration CO2 is directly toxic. [At lower levels we may be seeing effects of a reduction in the relative amount of oxygen rather than direct toxicity of CO2.]

And what about plants - well in wheat anything above 0.25% starts to decrease yields.

And what do any of your questions or my questions have to do with the affect of CO2 as a climate forcing agent?

Nothing!! It's a diversion.

Or What is the percentage of CO2 to all gases in our atmosphere? About 0.03 percent

But, your questions are irrelevant to discussion of climate! Since most gases have no effect on climate. The question that is relevant is how does the forcing of CO2 change with its concentration? Does it have a strong forcing effect at very low concentrations?

Your questions are designed to confuse and not to enlighten.

Nice try.
Member Since: October 24, 2005 Posts: 12 Comments: 1731
383. sebastianjer
4:15 AM GMT on July 04, 2008

Unlike you I am not the least bit afraid of CO2 reaching 450 or 500ppm. The fact is that we are going there whether you like it or not, so better get ready for it.

Member Since: August 26, 2005 Posts: 1030 Comments: 11197
382. streamtracker
4:13 AM GMT on July 04, 2008
#324 Gazer,

Wow, we agree about two things. Maybe we'd have a good time at a BBQ together. I can cook a mean steak.

NOAA has an Earth Systems Research Lab that monitors CO2 all over the world. One of the products they produce is a CO2 weather database that show the both the temporal and spatial variation of CO2 in the atmosphere. They put together a couple movies of CO2 weather during a yearly cycle.

CO2 Weather Movie

It's really amazing how the spatial distribution changes over time and how the concentration is highest nearest the poles. Which is incidentally where we see the greatest warming anomalies. The temporal variation is not as great in the southern hemisphere because less of that hemisphere's surface is terrestrial.

Source: Carbon Tracker
Member Since: October 24, 2005 Posts: 12 Comments: 1731
381. sebastianjer
4:12 AM GMT on July 04, 2008
Is CO2 a natural element or not? Is CO2 necessary for life on this planet or not? Do we exhale Co2 or not? Do plants breathe CO2 or not?

Does man make CO2 or not?

What is the percentage of CO2 to all gasses in our atmosphere?

What is the percentage of so called man made co2 to the total co2 in our atmosphere? What is the percentage all CO2 to all greenhouse gasses in our atmosphere and what is the percentage of so called man made CO2 to greenhouse gasses in the atmosphere.

Perhaps people who may be lurking will look these things up and be enlightened.

Happy 4th all
Member Since: August 26, 2005 Posts: 1030 Comments: 11197
380. streamtracker
3:56 AM GMT on July 04, 2008
#376 Jer,

Wow that's a new line of argument.

Sure the carbon is natural, but it would not be released for a very very very very long time except for our actions. We convert the buried carbon to CO2.

Since we extract it from geological reserves we are able to release it into the atmosphere at rates that are many orders of magnitude faster and much much sooner than it would had it been left to geological processes to do so.

So your argument is purely semantic and has no bearing whatsoever as to the significance of the release of that much CO2 that quickly.

And further more, no scientist says the molecules in CO2 are man made. What we say is that the emissions of Co2 from burning fossil fuels are anthropogenic and that is totally accurate.

And nobody would give a damn about increasing CO2 were it not for the rate of change, and our ability and natural systems ability to adapt.

And one more thing. If something natural could make and was making CO2 change that fast, we could not do anything about it. But, since we are the ones making it change that fast, we can do something. Get it??

So in the end what's different about "natural" versus "un-natural" CO2 emissions is we can decide. It's ultimately about the responsibility of taking our knowledge and using it to ensure a good future for our descendants.

So, you've gone on record as saying you think it's OK to roll the dice and hope that doubling CO2 in a 200 year period is safe thing to do. I prefer not to make that bet with my daughters future.

Paleo CO2 levels are very easy to measure accurately from ice core data. we now have 800,000 years of that kind of data. We have not gone over 300ppm in nearly a million years. And it has never doubled in concentration during that time period either. You ready to try and reach 450ppm or maybe 500ppm would be nice. Let's take our planet and use it to do a big experiment that won't be reversed for centuries at best. Sounds prudent to me.

So you bet that the forcing of doubling CO2 are at the lower end of the estimates. And bet the farm on the hope that tipping points won't be reached.
Member Since: October 24, 2005 Posts: 12 Comments: 1731
379. quasigeostropic
3:35 AM GMT on July 04, 2008
your analogy is twisted Simons...Co2 is needed for life on earth...radioactivity can actually destroy life......good night
Member Since: November 20, 2007 Posts: 21 Comments: 192
376. sebastianjer
3:21 AM GMT on July 04, 2008
Where does the CO2 that is emitted from fossil fuel come from? Is it not part of the natural ecosystem of the earth? Last I heard Big Bad Oil and Coal companies were not adding CO2 to their products CO2 is not man made it is natural. Although you would be hard pressed to convince people of this, CO2 having been made into some villainous element created by man to destroy the world. Go ahead Google Man Made CO2. Another of the little misrepresentations of the science of AGW. Man does not make Carbon Dioxide, it is natural.

Yet we refer to CO2 as if it comes two different places, one natural and the other MAN MADE And what are natural factors? Obviously using the reasoning of AGW alarmist, mankind is not natural. Is a forest fire started by lightening natural? It emits a tremendous amount of CO2, so should we receive carbon credits for extinguishing it before it burns out naturally? Wow the possibilities are endless.
Member Since: August 26, 2005 Posts: 1030 Comments: 11197
375. SWFLgazer
3:19 AM GMT on July 04, 2008
It's highly probable that over the long term, the past 30 years is very unususal.
Member Since: August 14, 2006 Posts: 0 Comments: 448
374. SWFLgazer
3:18 AM GMT on July 04, 2008
Heck...the definition of normal changes every year, because normal is defined as a rolling average of the past 30 years.
Member Since: August 14, 2006 Posts: 0 Comments: 448
373. SWFLgazer
3:15 AM GMT on July 04, 2008
You left the question of the"Think of the highest river level on the Mississippi river in the past 10 million years. Would you call that a drought or a flood?" What is normal?

Member Since: August 14, 2006 Posts: 0 Comments: 448
371. SWFLgazer
3:13 AM GMT on July 04, 2008
Every chart that I've seen shows that higher temps precede higher CO2 levels.
Member Since: August 14, 2006 Posts: 0 Comments: 448
370. SWFLgazer
3:08 AM GMT on July 04, 2008
Highest river lever lever since 1993?
Member Since: August 14, 2006 Posts: 0 Comments: 448
368. SWFLgazer
3:07 AM GMT on July 04, 2008
Now St SimonsIslandGAGuy...Which is cause and which is effect?
Member Since: August 14, 2006 Posts: 0 Comments: 448
366. SWFLgazer
3:04 AM GMT on July 04, 2008
If temps precede CO2, how can CO2 be a forcing of temps?
Member Since: August 14, 2006 Posts: 0 Comments: 448

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About RickyRood

I'm a professor at U Michigan and lead a course on climate change problem solving. These articles often come from and contribute to the course.

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