HOT TIMES: Electron microscopic picture of microfossils found in the drill cores. By studying the remains of such marine plankton, scientists gain an accurate perspective of past climate change.
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Atmospheric CO2 was the primary driver of a 400,000-year global warming event, known as the middle Eocene climatic optimum (MECO), according to a new study. The finding, which could help climatologists better understand the precise relationship between CO2 concentration and climate change today, is described in the November 5 issue of Science.
The climate trend across the entire Eocene, an epoch between 55 million and 34 million years ago, was actually characterized by long and gradual cooling. Much of that activity took place during the middle Eocene, when the planet transitioned from a warmer climate to a cooler one. But the MECO (about 40 million years ago) interrupted that trend, representing the last major temperature increase before the end of the epoch, which was marked by Antarctic glaciation. In order to investigate the role of CO2 during this warming episode, researchers analyzed sediment taken from deep beneath the ocean floor off the eastern coast of Tasmania. The core contained a record of fossils that spanned the relevant time interval.
The researchers relied on two separate organic proxies, also called paleothermometers, to reconstruct changes in sea-surface temperature during the MECO. Both are based on variation—due to temperature change—in structural characteristics of the molecular remains of specific microorganisms. In other words, the team analyzed specific molecules in which certain variations are known to be reflective of temperature change.
The MECO has for a long time been enigmatic to climate researchers, says study co-author Alexander Houben, a paleoecologist at Utrecht University in the Netherlands. Although there is lots of evidence for a large-scale temperature increase during this time, so far it's all been based on a different proxy: the occurrence of a specific oxygen isotope in ancient carbonate samples. Oxygen isotope values, however, are influenced not only by temperature, but also by seawater composition and changes in ocean ice flow. This study for the first time employs two independent proxies that "can clearly differentiate between temperature changes and other factors,” Houben says. The authors report that the paleothermometers indicated a warming of the sea surface during the MECO, at least in the southwestern Pacific, by 3 to 6 degrees Celsius.
To figure out how much atmospheric CO2 increased during the MECO, the researchers reconstructed the changes in its concentration by determining the ratio of stable carbon isotopes in organic molecules called alkenones. Variation in the composition of these molecules, produced by algae, can serve as an indicator of atmospheric CO2. Isotopic proportions are also influenced by the growth rate of the algae, which is proportional to the available food and nutrients in the water. So the authors considered multiple scenarios to account for variations in nutrient availability, concluding that CO2 concentration increased by a factor of two to three during the MECO.
James Zachos, a professor of Earth and planetary sciences at the University of California, Santa Cruz, who specializes in the time period and methodology used the study, said in an e-mail to Scientific American that apart from what may be an overestimation of the mean partial pressure of CO2, and the magnitude of its rise, "the data look reasonable." The study adds value, he says, because "the application of multiple proxy records in one core to reconstruct climate is unique, at least for this time interval."
The MECO makes for a useful "historical laboratory," Houben says, within which climate dynamics can be studied over a much longer timescale compared with other historical warming events of interest to climate researchers. By investigating CO2 variations and temperature dynamics over longer periods, researchers can obtain a clearer understanding of the still partly unknown role played by long-term climate feedbacks, such as changes in the ocean's carbon chemistry and/or large-scale changes in vegetation.
Currently, climatologists have a much better understanding of the role short-term feedbacks, such as changes in water vapor or sea ice. Incidentally, there were no glaciers at the time of the MECO, so Hoeben's group could look exclusively at the relationship between CO2 and temperature without having to account for the fact that changes in the amount of sea ice can increase temperature, too. "We've shown that if you include those long-term factors, then CO2 might very well be the leading factor for temperature increase, especially in a world without a major ice sheet," Houben says.
The result, he says, will help climatologists get a better grip on the concept of climate sensitivity—the degree to which a global temperature increase is entirely dependent on an accompanying rise in CO2. The authors conclude that the climate sensitivity during the MECO led to a 2- to 5-degree C increase per doubling of atmospheric CO2.
The study does leave one big question outstanding: Where did all the MECO CO2 come from? This remains an area of speculation, Houben says, although scientists are fairly sure the source was not organic. However the CO2 got there, the takeaway from this study is simple: "In the past," Zachos says, "whenever atmospheric carbon dioxide levels rise, the climate warms."
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Add Comment^ More deception.
Reply | Report Abuse | Link to thisNASA's GeoCARB III model:
http://www.aph.gov.au/library/pubs/ClimateChange/images/temp_co2_hist.jpg
Were temperatures and CO2 levels higher in the past? Both much higher, yet we are still alive. Does the above article show anything about causative effects? Nope. Temperature more likely increase due to solar activity, causing CO2 levels to rise as plant and animal life adjusted. This is what explains the "lag" in those ice cores datas that global warming proponents hide.
How about rephrasing that as "whenever the climate warms, atmospheric carbon dioxide levels rise."
Reply | Report Abuse | Link to thisMore warmth means more animal and plant activity DUH!.
The Greenhouse effect is the addition of an energy photon to a greenhouse gas causes warming.
IF the GHG controls this function then why hasn't all the water in the ocean vaporized?
If more GHG means more warming then just how do we get cooling? AND just how do you limit the GHE to just 33C if there is more water vapor and CO2 readily available? There is always excess GHG available in the ocean and air. It gets put there every night when the incoming energy level drops AND the GHE reduces adding more excess GHG to the air.
Reality is that the limiting factor is the amount of energy photons available to cause the GHE ( & other warming)
THe very idea that it is the CO2 that controls is absurd.
Instead of trying to blame all the ills of the world on CO2, try looking for a veration in energy input. The eccentricity of the orbit of Jupiter results in a cyclic variation in the amount of energy stored as gravitational potential energy. The energy gets released when Earth gets closer & it gets warmer (more kinetic energy). It gets stored as the distance between the two gets larger. This is a simple pendulum mechanism to vary the amount of energy available on Earth. It is not included in the so called climate models..
I find the acronym used to refer to this time period interesting. MECO Mid Eocene Climactic Optimum. All the climate scare folks are saying that we are witnessing the end of the world. Yet, the last time this happened, it was optimum.
Reply | Report Abuse | Link to thisI wonder how this would be explained?
Unless your Jupiter mechanism can move the earth closer to the Sun, or farther away, there is no net effect.
Reply | Report Abuse | Link to thisKinetic/Potential energy are only significantly important when you hit something. If the Earth hit something bigger than it is, OUCH! a few gigajouls either way would be meaningless. Even a large impact, like the one that killed the Dinosaurs didn't move the earth's orbit in any measurable way.
The Earth's orbit, like all the other planets is regulated by Jupiter. The gravitational pushes and pulls tend to move it into an ellipse close to circular. Jupiter is also in a close to circular elliptical orbit.
I am afraid that I can see no mechanism for the prediction you made. Can you elaborate?
This is a really curious report of new research, since several times in the past couple of months I've commented about how global warming during the Eocene produced really nice conditions near the Arctic, with palm trees and other tropical fauna. I did so after stumbling into the wikipedia entry:
Reply | Report Abuse | Link to thishttp://en.wikipedia.org/wiki/Eocene
It contains some other really interesting research material, for future research...
@JDoddsGW, the gravitational variation from the moon one day to the next is greater than the effects of Jupiter. Next you are going to say that the gravitational effect of obese Americans is causing global climate change.
Reply | Report Abuse | Link to thisI read something interesting several days ago that indicated a CO2 level below 150 ppm would result in the danger of dying vegetation and a severe reduction in oxygen over time. In an enclosed container study it was found that vegetation and animals survived just fine in a normal atmosphere with CO2 levels of 50,000 ppm or less.
Reply | Report Abuse | Link to thisIt made me wonder if we had a an enclosed container protected from the sun and we raised the level of CO2 inside the enclosed container from the current 390 ppm to a safe level of 10,000 ppm, how high would the temperature rise inside the closed container? My guess is it would not rise at all.
It would seem we are dangerously close to the lower safe limit of CO2 in the atmosphere at 390 ppm. it might be better if we tried to raise the level to a safer mid-range of between 5,000 ppm and 20,000 ppm. This would allow for a greater safe variability in the CO2 levels.
I suppose we could build some coal fired power plants in an attempt to increase the CO2 to the more safe levels. As long as we provided better air filters to remove the particulate from the stack discharge it would be a win win situation. We would have cheaper energy, more oxygen as the plants used the CO2 produced. We would have more food as the CO2 increased plant growth. Finally, increased plant growth would help feed the world's hungry.
@robert schmidt,
Reply | Report Abuse | Link to thisThe Obese Baseline American Micro Advance of climate change needs further study. Perhaps a grant from NASA or National Geographic could be sought?
Big cars. Do you realize how large an SUV had to be back then to cart around a family of Triceratops? Forget about it. MECO dinosaurs were far from green my friends.
Reply | Report Abuse | Link to thisAside from the need for an OBAMA climate change study, the last statement in the article tells another side of the story.
Reply | Report Abuse | Link to thisThe MECO CO2 source is unknown, but presumed to not be organic? And since there aren't all that many models which will allow for a large increase in the CO2 accretion on a planetary scale, there are according to the EPA:
* Animal and plant respiration, by which oxygen and nutrients are converted into CO2 and energy, and plant photosynthesis by which CO2 is removed from the atmosphere and stored as carbon in plant biomass;
* Ocean-atmosphere exchange, in which the oceans absorb and release CO2 at the sea surface; and
* Volcanic eruptions, which release carbon from rocks deep in the Earth’s crust (this source is very small).
@ http://www.epa.gov/climatechange/emissions/co2_natural.html
Which would presumably indicate that either there were an awfully large group of heavy breathing animals (must have been all those early mammals) and/or lots of plants OR a gigantic transfer of CO2 at the ocean-atmosphere interface.
But to simply blow that off with a statement such as:
"...However the CO2 got there, the takeaway from this study is simple: "In the past," Zachos says, "whenever atmospheric carbon dioxide levels rise, the climate warms."
However it got there? Leaving that issue out of the equation is convenient for finding a predetermined conclusion perhaps but doesn't speak to the causation behind the rise in CO2 at all! Which could leave the possibility of the Global Warming Event as the result of the increase in CO2 and not the other way around.
I would liken this to a significant personal weight gain from Late November through mid January as being caused by the increase in cranberry sauce consumption, since it is served with so many of the holiday meals.
Ergo, to reduce the Holiday Spread, I need only reduce the amount of cranberry sauce on my plate HOWEVER it happens to get there.
The different, multiple proxy use was a nice touch though, in leaving out the oxygen isotope variables.
Cart, horse, chicken, egg, cart, horse.....heat, CO2, horse, cart....
Your comment on period naming is most perceptive. These names were given long before the current panic over global warming.
Reply | Report Abuse | Link to thisWarmer periods being, in general, more conducive to life, have frequently been referred to as "optimum" by paleoclimatologists. For instance, the warmest part of the current holocene epoch, beginning 9000 years ago, is referred to as the "holocene climatic optimum".
With a little luck and a lot of CO2 we might top the temperatures of that optimum. If we're really lucky we'll kick ourselves out of the ice age that began a couple million years ago at the start of the pleistocene. In all the talk of global warming, the climate cassandras conveniently ignore the fact that our current climate is unusually cold compared to the norm since animal life colonized the land a few hundred million years ago.
Without people there to destroy the vegetation in building houses and killing the animals for food,the plants would get very large and so would the animals. The larger the animals had to get to reach the top of the plants, the more the CO2, and both plants and animals put off a great amount of heat. From the large pools of oil and coal, we know that there were places where there was a lot of plants and a large number of animals - like at a watering hole. So that tells me that if you want to cut down on CO2 build up - don't let a lot of plants and a lot of animals hang out together.
Reply | Report Abuse | Link to thisThe CO2 estimates from this paper are way, way off the charts.
Reply | Report Abuse | Link to thisOne estimate is 6,918 ppm (ranging from 5,560 to 8250). This methodology produces wild swings in estimates including near Zeros from other papers so this method should just be discarded.
From James Zachos work, we know there are small temperature spikes at 42Mya and 40Mya (the 42 Mya one is more interesting imo) but CO2 was only 900 to 1,400 ppm at the time.
The referenced study really points out that there is still much to learn regarding what drives climate change and specifically atmospheric CO2 changes. The more I have read on this subject, the more uncomfortable I have become with the basic research conducted by the key climate scientists involved in linking atmospheric CO2 changes to climate change, and the predicted rise in global temperatures. Check out the following link if you want to read more about the science and the individuals involved.
Reply | Report Abuse | Link to thishttp://assassinationscience.com/climategate/
Personally, I still believe that airborne CO2 is contributing to a warming climate. I just do not think it is going to warm nearly as fast as some AGW zealots have predicted, nor do I believe there is any evidence that a warmer planet would be worse overall for humanity.
I think it is obvious that people have been lead to take really stupid actions as a result of this debate. One example is the Cap and Trade legislation in California. Spending billions to create a bureaucracy around the subject of CO2-- when it is disputed as to what effect CO2 has on climate--- and the said CAP and Trade will do nothing for the climate--- that is so so stupid.
Funny how James Davis and Robert Schmidt have been deluded to support such wasteful ideas.
@Sisko, "The more I have read on this subject" you have read nothing on the subject except deniers blogs. But what would an article on climate change be without a heartland institute troll adding his two cents.
Reply | Report Abuse | Link to thisLOL Another typically stupid Robert Schmidt comment. You would appear to have have not even looked at the link I posted? The more information that becomes available, the more you stupidly ignore.
Reply | Report Abuse | Link to this@Robert here is another link to information and a number of science professionals. You would find it interesting if you'd take the time to read through the discussions. You can have real time blog discussions with those who study the science and the and the potential implications.
Reply | Report Abuse | Link to thishttp://judithcurry.com/
A funny thing I've noticed through these posts is the lack of inquiry about the portion of earth covered by forest/foliage during the time in which this CO2 was released.
Reply | Report Abuse | Link to thisWhat all of you have failed to take into account is that within the next 50 years, if nothing changes, we will have deforested more than half of earth (http://www.globalchange.umich.edu/globalchange2/current/lectures/deforest/deforest.html)--while at the same time experiencing a drastic rise in CO2. The remaining forests on earth will not be able to consume CO2 as there will be so much in excess, whereas in this Eocene period earth was independent of man and had its full forests and thus was much better equipped to handle an increase in CO2 levels and in temperature.
Some of you need to return to elementary school and re-read the chapters on "enclosed systems." Any enclosed system that experiences an excess of energy beyond its threshold begins to inhibit its own uptake--in the case of plants they STOP GROWING with excess CO2 beyond their threshold.
ConcernedCitizen,
Reply | Report Abuse | Link to thisIf you want to know more about causative effects, I suggest enrolling in a freshman or sophomore thermodynamics course. The reason it isn't explained here or in the Nature article is because, well, it's material that is covered in freshman or sophomore level courses.
JDoddsGW, same applies. You've been corrected before on this subject; yet, you still repeat your basic misunderstanding.
YABob, don't place too much meaning into one word of a name.
Garfiche,
See above, plus I think you'll find that animal production of CO2 is pretty much balanced, carbon-wise, with plants consumption of CO2. I can pretty much guarantee that if you quit feeding an animal carbon that was recently taken from the environment by a plant, that animal quits producing CO2 soon enough.
Kristoffer,
An interesting joke. Your aware that dinosaurs became extinct about 10 million years before the time that we're talking about?
I wish the author had included a mention of the PETM, which occurred 55 mya. One potential explanation of the PETM is a release of methane hydrates from the ocean. This would have been caused by a warming of the oceans enough to trigger said release, and in turn caused the large spike that appears in the geologic record.
They have the dynamic backwards....CO2 hikes are caused by plant die-off, which can be caused by any number of things, including the temperature change itself....
Reply | Report Abuse | Link to thisof course, if there were no HIGW, most of these clowns would be on the bread line....oh, wait! they're on the bread line now....they just get better salaries....
I looked at the link you posted and was surprised to see that an increase in CO2 levels actually preceded the extreme temperature rise in the Permian. If the graph you point to is correct, the abrupt CO2 rise did trigger a 10 degree C rise in global temperature which did not abate until a few million years ago when CO2 concentrations dropped to current levels.
Reply | Report Abuse | Link to thisWhen you state that both temperature and CO2 levels were much higher in the past yet "we are still alive" strikes me as silly. I was not present more than a few million years ago, and I doubt you were present either. Homo sapiens is perhaps 200,000 years old and is not likely to be well adapted to a 10 degree C temperature rise.
Ediddy-Heartland's Science Director Jay Lehr states "Carbon Dioxide is not a pollutant. On the contrary it makes crops and forests grow faster. Mapping by satellite shows that the earth has become about 6% greener overall in the past two decades, with forests expanding into arid regions. The Amazon rain forest was the biggest gainer, with two tons of additional biomass per acre per year. Certainly climate change does not help every region equally, but careful studies predict overall benefit, fewer storms, more rain, better crop yields, longer growing seasons, milder winters and decreasing heating costs in colder climates. The news is certainly not bad and on balance may be rather good."
Reply | Report Abuse | Link to thisI meant to add this link to the above post: http://somewhatreasonable.com/2010/10/whos-in-climate-denial-again-the-new-york-times/ . Plus there are some other good links in the comment section of this article.
Reply | Report Abuse | Link to thisThe big problem with this scenario is the rise in ocean levels. There are quite a few other problems with it as well.
Reply | Report Abuse | Link to thisI am aware CO2 is not a pollutant. In fact, I've seen it used for the very purpose of increasing crop yields--most modern greenhouses have CO2 emitters connected to an adjuster to keep CO2 levels at optimum levels.
Reply | Report Abuse | Link to thisNow imagine removing half the vegetation in that greenhouse and keeping the CO2 from adjusting accordingly, even more so, adjust the CO2 higher (as we currently do not know Earth's thresholds and will only continue to deforest and drive petrol-based engines).
The plants will begin to lose nutrients, what's worse, if the CO2 is not dramatically lowered within a short time they will
a. die from suffocation, starting to wilt and eventually stopping growth altogether
b. permanently stunt their growth, reducing their ability to consume CO2
c. will appear immune to the excess C02 at first, until other foliage dies and is not replenished at necessary rate, so that in time even the "immune" will die under the increasing cyclical stress of the system.
What we are seeing right now is the process in action. If nothing changes in 20 years we will have deforested near 3/4 of earth, added another 2 billion vehicles, and doubled the number of coal plants in China. The trees will cease to grow, and eventually unless a miracle occurs, so will everything. This is basic science.
The report does not make clear the methodology utilized to ensure that the CO2 increase was in fact a leading indicator of of temperature increase not a lagging indicator. Given the short article, I will give them benefit of the doubt and presume they pursued this point with due rigor because that is the real question. There are some disquieting points in the story however, such as "unsure where the CO2 came from". Folks aside from some major asteroid/comet interaction the CO2 we have to work with is already here. It must be from a volcanic source, biological source, or released from warming ocean water: and there is the problem. The authors concede they do not believe it to be biological, volcanic activity for the eocene is fairly well known so the authors appear to believe that it was not the source, I am unaware of any proposed major asteroid or comet in that period, consequently that leaves warming ocean water. The problem is the water must warm BEFORE the CO2 is released. So once again unless the authors found absolute proof that CO2 increased prior to the temperature increase, a very difficult piece of detective work when using biological proxies, there is a high probability that they have the cart and horse in the wrong order.
Reply | Report Abuse | Link to thisThe crazies who think the laws of physics are liberal plots, conceived to take political power from Big Oil and Coal and give it to sustainable energy industries... are thick here.
Reply | Report Abuse | Link to thisIt is not about the laws of physics being perceived as plots, quite to the contrary. If you read the history of science you can find many occasions where the mainstream of thought was turned on its head by people trained in the institutional thinking but not willing to buy the story hook line an sinker. The Nobel Laureate geneticist Barbara McClintock is a classic example. She was laughed out of meetings for many years, thought of as a crackpot. In the end of course, she proved to be correct and the establishment of science was dead wrong although you will find few that admit it today. Science is an industry much like the energy or environmental industries. They all fall prey to the same failings, i.e. protecting their particular dogma at all costs. It is up to those not trapped by such systems to force adherence to a standard. I hope that the researchers in the aforementioned article have done due diligence and assured their evidence clearly shows a rising CO2 concentration leading the temperature change. If so they will be the first to have accomplished it. The fact that this particular finding is not front and center leaves me with doubts. I anticipate that upon reading the full article the authors will have documented a concomitant rise in both CO2 and temperature but will little power to determine which came first. I will give them the benefit of the doubt for now. If however the study shows no real statistical power to support its claim, do you think that will make a headline in the SciAM newsletter? I am doubtful.
Reply | Report Abuse | Link to thisConcerning the debate of whether climate change is driven by increase of CO2, I think the incomplete state of current research does not preclude climate change institutions from addressing pressing issues.
Reply | Report Abuse | Link to thisAlready, there is disruption of various activities and livelihoods due to unusual climate variability, especially in developing countries. It seems responsible to help people to adapt to hazards linked to disrupted livelihood and habitat.
A few more comments.
Reply | Report Abuse | Link to thisFirst, Water, Methane and Chlorofluorocarbons are all more important to Earth global warming than CO2. CO2 is just not very effective at it. Chlorofluorocarbons are no longer being released in the US, though they are still being manufactured in the developing world, including Latin America, China and India. They are discourages because of the effect on Ozone. They have a tremendous effect as a greenhouse gas. (On the order of 10,000 times more than CO2 per the Handbook of Chemistry and Physics.)
Methane and water vapor have their effect because of both larger IR diffusion and concentration. CO2 is 4th in contribution from what I have seen. It's just only the second one we can regulate. (CFC's are already regulated everywhere that is willing to do so.)
responding to a few comments,
#1, Concerned Citizen,
Yes, there have been times in the past when temperatures and CO2 levels were higher in the past. And, yes, we are still alive. But, there are effects on us from levels we are not used to. Also don't ignore the fact that it is easier to fix a problem early than later. I agree that we do need to establish what is a problem, but that means we need more science research, not more politics. There are also reasons to want to pursue the policies for control of carbon, because it is the economic interests of the US. Let the rest of the world follow us.
#2, JDoddsGW,
The CO2 levels are not the totality. There may be other causes, but we have other reasons to act. See my response to #1 above.
On the whole Jupiter thing, I really would like to see some reasons. It will take calculus to explain it. Orbital mechanics is a messy endeavor with it. Impossible without it. Please tell us more. Include the math. Without the math, it is just rambling. It is a way out idea, but, if supported, it just might be significant. Come on, prove it.
#6, tfagan,
I did a quick Google on it. CO2 levels above 7,000 PPM are fatal to Mammals. Some other animals can withstand higher levels, but not a lot higher. Plants will withstand higher levels than Animals, but most don't like it. Bacteria are the ones that don't care. Humans appear to be fine up to about 2,000 PPM CO2, per The Canadian Centre for Occupational Health and Safety(ref http://www.ccohs.ca/oshanswers/chemicals/chem_profiles/carbon_dioxide/health_cd.html) I think your figures there slipped a digit.
Numbers higher than around 1,000 PPM CO2 don't seem to be in evidence since the Pre-Cambrian.
Continued...
Reply | Report Abuse | Link to thisAbove around 500 PPM, the acid effects of carbolic acid (CO2 in water is an acid) become biologically significant. Some claim that this is already happening in the oceans. That is a concern too.
#12 JamesDavis,
While you are correct that we need plants and animals, you overstate it. Long before oxygen becomes a problem, we will run out of food if the paving of the planet you seem to fear happens. Fortunatly, plants seem to have faster growth when CO2 levels, up to around 500 to 1,000 PPM. I don't believe your fears are well founded.
#18 ediddy0321.
Unfortunately, fossil evidence tells us what one particular area was like, but not large areas. I doubt that you can find what the whole earth was like at any period after the Pennsylvanian. That was the time of large forests that left most of the worlds coal deposits. You will have to accept the kind of indirect evidence that this Article gives. Also, you make the mistake in your assertions that total forested land is decreasing linearly. It is not. Non-linear growth and harvesting are both occurring. Much of the forest land is being replaced with low growth jungle which locks up carbon much quicker than the large trees do. It is not a simple predictive process. Trees are getting more valuable. They may soon be more valuable as trees to the local economy than they might be as timber or firewood. That was the case in pre-Colombian times in both East Coast North America, and in Amazonian South America. Supply will change demand, and provide new demands.
#19, Chris G.
First, re: Optimum in Mid Eocene Climatic Optimum (MECO) It is not just a word. It is a description. The time mentioned was when most of the Mammal and bird families we see today came into being. So did a lot of other species and families. Apparently, animal and plant life both exploded, similar to what we still find in rain forests today. This is all from fossil evidence. It was called Optimum for a reason. Check it out. It is a fascinating time period.
Second, a minor nit-pick in your response to Garfiche. Plant and animal production do not completely balance. There is always a small excess of plant matter. This balances the CO2 introduced by fires, volcanoes, etc. The excess plant matter gets worked in underground by a variety of processes. that is why we have coal. It is the old excess. This does not mean that you were wrong in your response, you were actually right. I hope this doesn't upset you.
Various, Sisko/Schmidt,
Reply | Report Abuse | Link to thisYou both seem to be mostly politically motivated. Evidence, including (especially including) contradictory evidence is vital to real science. you seem to lack that. A hint, the major web sites both for and against Global Warming/Cooling are heavily biased. This indicated a political, not a logical foundation. Political beliefs are primarily emotional, as are both of your posts. It is rational processes that will eventually determine what is right. In the end, it may not matter. We need more research, not more argument. If the researchers believe for or against the hypothesis, it doesn't matter, as long as they are honest, and present all of their evidence. The evidence will decide.
Continued more ...
Reply | Report Abuse | Link to this20, jonryker,
Unfortunately, the dating for times older than 1 Million Years are not terribly precise. When you add the Plus or Minus for the dates, we really don't know if the CO2 happened before or after the warming. At least for dates more than 20 MYA. I am afraid this sends you back to go. Like me, you need more information. That means we need more research.
#21, conservit,
That there were higher levels neither proves nor disproves the central hypothesis. what it means is that our ancestors were able to do just fine back then, so we probably will too, if those conditions return. Note the probably. It is certain that some species will disappear, and some new ones will appear. But that is just what has always happened. We just don't want to be one that disappears.
#21, Postman1,
It is true as you state that CO2 is not a "pollutant". However, it is also true that different species have different tolerances to the amount in the environment. The worry is that the amount in the atmosphere MIGHT exceed the ability of many species to deal with it. I am not sure you understand the problem. CO2 levels in the atmosphere up to 500 PPM don't seem to be a show stopper, however, there are other things involved. It's not just all about CO2. we are currently about 1/2 way from the Ice Age level of CO2 to the danger level. we don't know what will happen at that point, or now it will progress, as it is not a linear process.
#24, noretreat,
Most of the rise in sea level has already happened. The Oceans were around 200 meters lower than they are now during the height of the last Ice Age. The entire black sea, and most of the Mediterranean sea dried up. The highest they have ever been is between 10 and 20 Meters higher than today. That was when ALL the Ice was melted. We are not sure if the total amount of water was the same then as it is now. there are processes by which water is slowly lost. Some are rather abrupt. The figures I have seen for ocean rise indicate less than 1 milimeter per year. That is with an uncertainty that is larger than the measurement. Certainly, over the last 2000 years there has not been any major rise in sea level. There have been some land rise in some areas and fall in others. But this process is always happening, with or without any global climate change. By the way, there is no natural point in the state of Florida that is over 10 Meters above Sea level.
Even More ...
Reply | Report Abuse | Link to this#25, ediddy0321,
We will never reach the point you fear, because we need the farmland. For petroleum, you don't need to worry about it for more than the next 20 years, because, while we will never run completely out of it, we are already running out of what is cheap and easy to get. within 20 years, something else will be less expensive. At that point, petroleum based cars are dead. Coal, now is a problem.
#26, Quinn the Eskimo, Amusing troll.
#27,ssm1959, The evidence is not all in. See responses above on timing. This is why more research is needed. Don't draw final conclusions yet. On that time scale, cart and horse are uncertain at best. Do not expect that to change.
#28, Beam me up Scotty, Nice troll.
Don't get your hopes up on Big Oil and Big Coal. If you look around, Big Oil and Big Coal are trying very hard to become Big Wind and Big Solar. They are also major players in the pushes for Big Bio-fuel and Big Carbon Sequestration. For corporations, the accent is on Big, they don't really care what makes the money, as long as they make the money. They are trying to back all the horses in the race. They want everything but ethics. Kind of like politicians that way.
#30, Fabrice LOTY,
The "climactic" disruption in 3rd world countries is mostly due to politics. The best solutions are education and classical economics ala Adam Smith. They will rise best if given just a little help, and left to do what they determine is in their own best interest. Respect is better than remote control. The hottest places on earth continue to be in the Sahara, the Empty Quarter, and the American Southwest. That hasn't changed in the last 100 years, and doesn't look to be changing.
If you have followed all of this, you are very patient. I was feeling a bit restless, so tried to respond to all the posts. I am sure some of you will be able to expand on anything I have said.
Agree or disagree, we all learn from the discussion. Please give reasons, not just invective and name calling. That provides no instruction.
@YetAnother Bob-
Reply | Report Abuse | Link to thisThe exact "science" regarding AGW is clearly not settled as more and more is learned on the subject. Is atmospheric CO2 increasing? Yes. Is, this contributing to increased temperatures on earth-- almost certainly yes, but to what degree is certainly subject to debate and will not be known without years of further analysis. There are clearly secondary effects that drive both the emissions numbers and the concentration numbers and there are other factors that some of the "AGW zealots" have tried to get the general population and politicians to ignore.
What should be done by 150 different governments is a political question and not one that will be decided by science. Some scientists have been pushing for governmental actions that their scientific research does not yet support as a logical conclusion.
Over the long term- say next 100 years-, the issue, in my opinion; is worldwide emissions per capita. As the currently less developed portion of the world develops, a significant rise in emissions will be unpreventable. Today the worldwide average is approximately 6.0 tons per person per year. It will rise to somewhere around 18 tons per person per year on average as the worldwide population develops a "modern infrastructure". Current US emissions are around 24 tons per person per year. It would not be that difficult to lower US emissions, but that will have a negligible impact on the world total, and no impact on the climate.
At the end of the day, actual decisions will need to be made, and hopefully those decisions will be logical and supportable based on reasonable data. The United States should make decisions that are in it own best interests.
YetAnotherBob,
Reply | Report Abuse | Link to thisMostly correct. However...
"The greenhouse effectiveness of a gas in the atmosphere depends, in part, on its concentration. As the atmospheric
concentration of a gas increases, the effectiveness of additional gas decreases. "
http://www.tpub.com/content/altfuels02/3299/32990018.htm
What you have described is effectiveness per mole (see Avogadro constant/number for any that don't know what that means). That is, there is a lot less of the gasses you name as GHGs more effective than CO2; so, their effectiveness per mole is higher, but the effect of what is actually in the atmosphere is less.
http://cdiac.ornl.gov/pns/current_ghg.html
Yes, I know that there is not a perfect balance between plants and animals with regard to the carbon cycle. There really very little coal formation going on at this time; mostly what does not decay is what makes up the difference between black, river-bottom dirt, and sandy, tan desert dirt.
Also, let's not confuse the toxic effects of CO2 at high concentrations with the thermodynamict effects that it has on our planet's energy balance.
Bob, ever hear of a pendulum. As it swings the energy in it goes from stored potential energy at the top to kinetic energy (in this case velocity) at the bottom.
Reply | Report Abuse | Link to thisIn the case of the Earth the Earth's elliptical orbit is caused by (mostly) gravity attraction by Jupiter. The Earth goes from .98AU to 1.02 AU in its ellipse. So yes Jupiters force of gravity causes the Earth to go closer to & further away from the sun. An energy transfer does NOT require hitting another object as long as there is a mechanism to transfer the energy. Gravity is the mechanism.
Robert Schmidt: Yes I agree BUT the moon 's variation is approximately monthly and when you do a yearly average temperature (as most of the climate calculations are) then the variations cancel out to a yearly average which does not change "much".
Reply | Report Abuse | Link to thisMy claim in the paper John Dodds Wobble Theory of global warming" in www.scribd.com is that There are many sources of energy into the Earth that are not accounted for in IPCC etc global warming calculations. There is daily earth rotation that givees us a 10-15C variation, there is almost monthly moon gravity, there is yearly Earth orbit eccentricty, and then not accounted for there is a 12 year variation from Jupiters gravity which mostly causes Earth eccentricity,(this can be seen in a 5 yr averaged GISS or HADLEY temp curve also in my paper) there is a 60 year Jupiter/Saturn resonance orbit eccentricity which accounts for the 60 year cycle from Earth temp peaks in 1880, 1940, 1998..., there is a 900+ year Jupiter eccentriity, there is a 50,000 or 60,000 year Jupiter exccentrity, there are several longer Jupiter eccentricities which will translate directly to Earth eccentricities which correspond to ice age durations.
In summary there are too many "coincidences" in timings AND a mechanism to account for them that they can be ignored. The current global warming models fail to account for them.
There is also a tiny little problem in that CO2 can't add energy. It is the energy photon in the Greenhouse effect that adds the energy to cause warming. IPCC & Arrhenius say the greenhouse effect says "more GHGS causes more warming". This is WRONG. Every night when man is dding more CO2, the temperature goes DOWN. There is also the fat that when it rains and you add more GHGs the temperature does NOT go up. The "more GHG means more warming statement" is WRONG. Arrhenius camre top the wrong conclusion Instead of more GHGs means more warming he should have said More Photons means more warming. I at least have proposed a theory to explain it.
Re the Jupiter comment: and the proof.
Reply | Report Abuse | Link to thisThe proof is contained in the paper John Dodds Wobble theory of GLobal Warming. available at www.scribd.com. JUst where is the proof that more CO2 (GHGs) causes more warming? It does in the lab, but in the real world it fails. I can prove every night that it is wrong. Every night as man produces more CO2 the temperature goes DOWN Instant proof that CO2 does not cause more warming. It is the addition of the energy photon that causes the warming in the GHE. More photons in the morning means warmer temperatures. Fewer photons at night means lower temperature & less GHE.
Arrhenius' 1896 paper jumps to this same incorrect conclusion that more GHGs means more warming. The new climate scientists are too lazy to look to see if it is valid. More simple proof- when it rains we get more GHGs - they can triple from 30 to 100% humidity, AND YET, the temperature does not go up, let alone triple since Water Vapor is the majority cause of the GHE warming.
I do mot dispute that the GHE exists, just that it is the number of added energy photons that causes it, not the GHGs. Whenever the sun goes down and the GHE reduces, then the unused GHGs become excess in the air.
I also do not dispute that the world has warmed (& cooled) in 60 year cycles since they started keeping temp measurements. BUT my gravity causes eccentricity which causes variation in available energy accounts of these 60 year cycles and also for ice age cycles and also for cooling. Adding CO2 can NOT account for cooling.
Re 36 Sisko & Bob: The science behind AGW is not exact comment/
Reply | Report Abuse | Link to thisTry this:
As I understanfd the AGW theory more MAN added CO2 causes warming which raises the temperature, which adds more water vapor "feedback" which further raises the temperature by added GHE. BUT because there is excess unused GHGs in the air and ocean then they will be used whenever there is added photons to cause more warming (ie every morning). Current warming has NOT vaporized all the water in the ocean. There must be something that stops it if the theory that more GHGs means more warming is valid, BUT if the theory that the number of photons stops it is valid then you will get a cyclical warming and cooling from eccentricity.
Now if more photons causes warming then AND there is excess GHGs in the air and ocean, then the GHE warming will stop when all the photons are in use. This means that when you add CO2 it becomes excess to what is already there. It does not cause more warming. or more WV. and besides any added photon that comes in would use the excess water vapor already in the air, rather than wait for man to add CO2 to cause warming to then cause more WV to evaporate. SO bottom line man has nothing to do with causing the temperature. There is no such thing as man caused feedback. Yet another failure of the climate models. Garbage in garbage out.
To YetAnotherBob:
Reply | Report Abuse | Link to thisit can be explained by the fact that they said "climactic" optimum, rather than "climatic"
The article does not indicate if a rise in atmospheric CO2 concentration caused a rise in temperature or if a rise in temperature caused a rise in atmospheric CO2 concentration. No cause and effect seems to be substantiated.
Reply | Report Abuse | Link to this"...then CO2 might very well be the leading factor for temperature increase" doesnt sound quite as strong as the headline indicated.
Reply | Report Abuse | Link to thisif the article was an exam question ie comment including assuptions and sensitivity of conclusions these comments would not get 5 out of 10
Reply | Report Abuse | Link to thisif the article was an exam question ie comment including assuptions and sensitivity of conclusions these comments would not get 5 out of 10
Reply | Report Abuse | Link to thisif the article was an exam question ie comment including assuptions and sensitivity of conclusions these comments would not get 5 out of 10
Reply | Report Abuse | Link to this