nemov


Malthus may have been unable to anticipate the industrial age and the subsequent advances in agriculture and transportation but he was in essence correct in his thinking. Nothing can go on forever growing geometrically. Either it will limit itself to something approximating a steady population or it will be limited brutally by a lack of resources. There are plenty of examples in biology of this and numerous examples in human prehistory and even the contemporary world. Our world now faces a double Malthusian crisis with a population still growing and a per capita use of resources also growing exponentially. Anyway, the scientists studying global warming are hardly as limited in their frame of reference as was Malthus. The study of climate change is one of the most extensive and sophisticated scientific projects ever undertaken. Sure there are some wild technological approaches that might limit rising temperatures like seeding the oceans with iron to promote plankton growth or launching huge solar mirrors to limit the sunlight reaching earth but who knows what kinds of secondary consequences such massive undertakings would have. Its much better to pick the low hanging fruit first with selected policies now and then move to more expensive ones to try to restore the natural state of the atmosphere before moving to radical technological solutions that may cause additional chaos.

lederuvpac


One more time, the greenhouse gas effect is basic physics. It's been discussed and studied since 1827 (for water vapor) and since 1896(for CO2). The earth and the moon are approximately equally far from the sum and moving around it in roughly the same orbit. Yet the average surface temperature of the earth has been about 15 degrees C while that of the moon is -18 degrees C. The difference is entirely due to the misnamed greenhouse effect. The major component gases of the earth's atmosphere, like nitrogen and oxygen play little or no role in this phenomenon since they are transparent to both to the solar radiation (mostly the visible spectrum and some near infra red - 0.4 to 0.7 micrometers)and infra red radiation. They do reflect some of the incoming sunlight but this would cool rather than warm the earth. The solar radiation, that strikes the earth, warms it. The earth acting as a so called Black Body reradiates exactly the amount of radiation it receives but from a surface temperature far lower than the sun's 6,000 degrees K. Black Body radiation from a surface of 15 degrees C is largely in the infrared - 4 to 100 micrometers. Water vapor in the atmosphere absorbs this radiation in the 4 to 7 micrometer range. CO2 absorbs in the 13 to 19 micrometer range. Ordinarily the 70% of the earths radiation in the 7 to 13 micrometer range would escape freely into space but some of the other non natural green house now absorb some of this radiation. As the various gases absorb radiation it heats up and reradiates at frequencies corresponding to the Black Box radiation of the temperature they reach. Some of this reradiation is upward and some is downward. The net quantity of reradiated energy that strikes the earth heats and warms it. This is what we call the greenhouse effect. Adding to the amount of CO2, as we have been doing, adds to the amount of earth radiation in the 13 to 19 micrometer range that is retained and reradiated to the earths surface. Adding other greenhouse gases adds to the amount retained and reradiated in the 7 to 13 micrometer range. Water vapor has by far the greatest greenhouse effect but the amount of water vapor in the atmosphere is a function of the temperature thus it acts a positive reinforcement of the GH effect of other greenhouse gases. New Scientist Article (requires subscription)

Now what's illogical about that? Even the GH critics accept the basic science of the phenomenon. The arguments have been about whether is was self regulating (positive vs negative feedbacks), how strong the effect was (sensitivity), and the like.
Unfortunately that have had to give ground repeatedly as the evidence mounted. For all our sakes, I wish they were right but wishing and ignoring evidence doesn't make it so.

I would only agree with this assessment if there were high certainty that the Earth was at risk. Even if you believe that human induced global warming is real it is not exactly clear what the repercussions would be other than the change = bad arguments that are constantly made. We keep being told that over the last 10 years there has been a catastrophic increase in temperature. I live on the Gulf of Mexico. Siesta Key is still there. The glaciers are melting, the sea hasn’t swallowed Lido key. The sea has risen an average of 18cm per century. There was not an increase in this rate during the strong warming that occurred in the first half of the twentieth century nor did the rate decrease when the climate cooled between 1940 and 1975.

It does not make sense to address something that may not be a problem.

True, it has not been proven beyond any reasonable doubt to be a serious problem; what we have right now is a preponderance of evidence supporting the hypothesis that it will be a serious problem. The fact is, we make decisions under uncertainty all the time. NOT taking action is a decision, too, and we can turn your logic around and ask, "what is the justification for not taking action when it may be a serious problem?" We make huge expensive decisions in a climate of uncertainty all the time -- the invasion of Iraq, for example. The existence of uncertainty doesn't make the decision nonsensical; it makes perfect sense to take action on something that might be a problem. It depends on how serious the problem could become and how much it will cost us to prevent it. There's broad agreement that global warming could easily cost many trillions of dollars, so it does make sense to spend millions or billions of dollars heading it off. As we grow more certain, the amount of money we should be willing to spend should increase to match the likely costs of global warming. Thus, when we reach 100% certainty, we'll be spending trillions of dollars on the problem. Some billions of dollars now seems pretty paltry in comparison. Like Senator Dirksen said so long ago, "A billion dollars here, a billion dollars there, pretty soon you're talking about real money."

Go ahead and cite that. There seems to be a consensus (over half) among scientists that the earth is warming due to human activity. Where is this preponderance of evidence that supports the case it will be a big problem? Those are two very different questions. Especially when you consider no one can accurately predict the future changes. I also assume that you do concede that progress is being made in the areas you mentioned earlier since you did not respond to that.

There is little controversy that the magnitude of warming that we are projecting for the rest of the century will cause a great many problems. We have yet to quantify many of those ramifications; the few we have done are all horrendously expensive. For example, one preliminary study attempted to determine the cost of a rise in sea level of one foot on just the eastern seaboard of the USA, and concluded that it would run into at least hundreds of millions, probably billions. One big cost for America would be the decrease in soil hydration in the midwest arising from global warming; one study estimated that this could cut the American wheat and corn crops in half. How much is that worth?

It's true that all these studies are preliminary. But there isn't much question that, whatever the particulars, the costs will be enormous.



Of course progress is being in many areas! I don't deny the impact of technological progress, I object to the blithe assumption that we don't have to worry about a looming problem because technology is certain to solve it for us. And we won't be funding the research on those new technologies if we deny that there's a problem to be solved, will we?

Technology changes, and improves our capabilities by leaps and bounds, but having better tools doesn't always answer the questions that need to be answered, and even when technology does answer questions, we often have new problems to address as a result of our progress.
Science itself, and the knowledge we gain of it, is a much more tedious process.
GW problems will be gradual enough for us to adapt, and numbers of dollars presented to accomplish adaptation are a wild, wild guess at best.
The idea of throwing money at GW to prevent it is not going to be acceptable to the taxpayer. Even if over half of us agree with what the scientists are telling us, none of us want to be taxed to prevent something that we are not totally convinced will happen, especially knowing that man's contribution is a small part of the problem, even tho that small part has been going on for almost 200 years.
Changing weather is dangerous stuff, it has been done on a small scale and the experimenters had the devil scared out of them. Saw that on one of the science channels, don't remember the place, but they caused a powerful localized storm by seeding clouds in an attempt to keep the damage from happening some place else. It worked, too well.
I am not afraid, but I am doing my part to conserve. I am doing it because I know that the costs of energy will not likely decrease, ever, so I will do what I can to minimize use of it.
That is what we should be doing anyway, as long as we can do it without major disruptions to the economy.

There is no physical evidence that the sea level is going to rise a foot. Like I mentioned earlier on average is rises 18cm every 100 years regardless of the temperature changes over the past 100 years. There have been studies that a warmer climate would increase the crop yields in the US. How much is that worth?

Hey i have looked at the facts and i have read the articles just the same as you and have made the conclusion that the heating/cooling of the earth is as natural as you can get. I mean if you look at this chart about the history of climate on the planet...our current period isn't even close to the temperatures of earlier periods. The temperature of the earth fluctuated for millions upon millions of years with no humans, no factories, and no SUVs. Is it truly rational for me to believe then that excess gases emmitted during only about the past 200 years can have such an enormous impact?

A lot of scientists say that global warming is a great threat. But a lot say that it isn't. I mean Global Warming is a great theory because basically anything can prove it.



Apples and oranges. Just because one theory was proven correct isn't a guarantee that all other theories are as well. That is why it is a Theory. Until it is proven true...which it cannot be done without at the very least hundreds or thousands of years of research.



I am not disputing greenhouse gases. This has been going on for billions of years on this planet...it's nothing new. Which is why i don't believe that the human activity for the past 150 years or so has anything to do with a major climate shift. Its shifted without humans before and it will eventually shift again. It is inevitable. To say that is somehow preventable is only to say it can be stalled.

nemov


Please cite a study that indicates crop yields in the U.S. will increase with higher temperatures and the vintage. Some skeptics have made back of the envelope estimates about how much yields should increase with with a doubling of CO2. The only recent real studies I've seen reach quite the opposite conclusion. These were of 2 types. One set sought to duplicate the conditions of a globally warmed world in temperature and gas composition of the atmosphere. The other looked at historical temperature versus yield data. Both concluded that in the major grain growing regions higher temperatures lowered yield. For rice, a 1 degree C average minimum temperature resulted in a 10 per cent decline in grain yield. Here are a few accounts of such studies Example 1, Example 2, Example 3. I have seen some European studies circa 1996 that gave mixed results for different locations.

lederuvpac


What you believe has little meaning unless it is founded on some information. All the evidence is that humans are having an effect on climate and most of the critics have shifted their argument from "its not happening" to "its going to be a small change and we can adapt to it." Unfortunately, its just as likely to be a large change as a small one. No climate scientist would dispute that very large changes have occurred in climate when measured in terms of hundreds of thousands or even 10s of thousands of years. Our human civilizations, however, have developed in the last 10,000 years of reasonably stable climate. (Yes, I am aware that there have been some regional shifts in climate in that period, but the average temperature varied only marginally). We now live at a particularly vulnerable time went human populations have reached the carrying capacity of natural systems and populations can't move to other locations (with limited exceptions) in response to general climate change. Not responding with at least low cost no cost solutions and preparing to respond more comprehensively, may well be sentencing millions to starvation and may produce a major economic crisis for the rest of the world.

The original article that I posted with this topic addressed this very point. The studies are out there, they are just not widely reported.



I take most of these doomsday scenarios with a grain of salt. The environmental advocates are just trying drum up support just like any other political entity. It is funny but some evangelical groups are starting to talk about global warming as a problem. Wouldn’t that be a strange alliance?

Now THAT is frightening. When the money grubbers of the religious persausion can recognize the potential for seperating us fools from our money using an issue that has little, or most likely nothing, to do with religion, we are in deep trouble.

There are many, I suppose, who are afraid of the slippery slope triggering event that will cause mass extinctions, similar to whatever killed the dinosuaurs.
But even that took a very long time, compared to the lifespan of humans, but a short time geologically speaking.

When it happens (if it happens) we will have no choice but to adapt, mostly by making lifestyle changes. Until then, I remain as unconvinced that the sky is falling over this issue as I was about the Y2K issue.

I have come to the conclusion that our response to global warming will be much like our response to terrorism. As I observed elsewhere, most Americans' reaction to 9/11 was "how could this have happened?!?!?" while my own reaction was "what did you expect?" Reading some of the postings here, I think we're in for much the same experience. Denial, rejection, and ignorance, followed by some catastrophe. The French were convinced by the heat wave in France that killed thousands. That heat wave may have had nothing to do with global warming. It's hard to guess what kind of disaster will hit the headlines. Perhaps a melting glacier will suddenly slip, releasing a huge flood that wipes out a town downvalley. Perhaps a big heat wave will kill thousands. Perhaps a nasty drought will wipe out crops in several states. Whatever it is, it won't be reasoned scientific analysis that sways Americans -- it will be some spectacular event, especially if it generates good video for the news, possibly having little to do with global warming. Then all of a sudden we'll be sending the Marines to Alaska to blast glaciers, enacting draconian laws punishing those who think warm thoughts, and spending billions of dollars on air conditioners.

Some people learn by reading, study, and analysis. Some people learn by body counts and film at 11. Eventually, everybody learns.

Results like these would indeed be awe inspiring. How many times has the end of the world come? Things are never as good or as bad as they seem.

nemov


Original Article

These are the kinds of articles I find so infuriating. No studies are cited and people are quoted out of context without characterizing their credentials. It's difficult not to conclude that such pieces aren't part of the organized disinformation campaign rather than the expression of true skepticism about the science.

In trying to ascertain the bona fides of the article I first Googled the author, Robert Matthews. I found that he was indeed a science correspondent for the Telegraph group. I could only find a few articles of his on line and they all took a critical position toward GW science. I next looked for the people he quoted in this article.

Phillip Stott is a well known skeptic with a website debunking scientific studies of GW. See this Writeup. His website is located Here. The thrust of the article is devoted to "information" garnered from this questionable source.

Sir Liam Donaldson seems to be legitimate but the reference to his findings are hardly damming to the consensus scientific view. Someone raised the concern of malaria and as chief medical officer he looked into it and issued some reassurances.

The author makes reference to "more sophisticated studies" that debunk studies that anticipated lower yields with rising temperature but cites none. The best he can do is to reference some economic studies indicating greater tourism in some regions as a result of warming. I'm afraid that won't feed the world.

This is not a scientific study nor an abstract of one nor a press release of one nor does it cite one. If they're out there, point me to one. I even believe there might be a few that are at least ambiguous but I think if one is going to be skeptical of the main stream science one should at least dig up some hard research that tends to support one's position.

Most of these studies hardly are mentioned in the press so it is difficult to cite them directly. Like this one example



It is not news when a study finds that we will be able to adapt to whatever changes take place. How would you make this a sexy headline?



Humans have survived much more extreme weather in less technological times. We will be able to adapt if need be, it does not make sense to make changes that could harm citizens economically if there is no problem.

I'd like to point out that the real significance of global warming may not lie in the warming/cooling aspect but in the change of temperature. That is, warming brings some benefits and some costs, but change always brings costs, because our entire infrastructure has been built with assumptions of temperature stability.

Consider, for example, the mundane problem of air conditioning. Right now, people in warm climates have lots of air conditioning, and people in cool areas don't bother. This is one reason why heat waves always kill more people in cool areas than in warm areas -- they don't have the infrastructure to cope. If the temperature rises in cool areas, then we'll need to install air conditioning in millions of buildings. How many billions of dollars will that cost us?

Or take the equally boring issue of flood control. All over the world, there are systems of dams, drainage canals, and water release areas that are meant to take up the load when there's too much rain. If we get more rain, then we'll have to spend billions of dollars on new dams, drainage canals, etc, to cope. This will be especially expensive in cities, where an overloaded storm drain system can cause millions of dollars in damages. We'll have to dig up all the sewers in many of our cities and install larger systems. And of course, all this will be preceded by all the unexpected deaths and property damage arising from floods.

Some areas won't get more rain; they'll get less. Farmers who relied on rainwater will find themselves unable to grow crops. They might be able to build new irrigation systems based on groundwater -- but it will cost billions of dollars.

Here's a good one for you: the loss of permafrost. In far northern areas, the ground is permanently frozen and all structures are built with an eye towards permafrost. But the permafrost is melting in many areas, and what was once solid ground is now soft muck. Guess what that does to all those structures? Worse, the annual cycle of freezing/thawing yields all manner of interesting behavior sometimes called "heaving". Caskets in cemetaries rise to the surface. Buried pipes buckle and break. Building foundations shift. More billions to adjust to the new climate.

Especially serious are the ecosystem effects. Ecosystems optimize themselves for a certain temperature range. They have some flexibility in adjusting to changes, but that flexibility is limited. They can handle changes taking place over thousands of years, but not decades. If a change happens too quickly, the ecosystem collapses.

For example, I live in an area near the southern edge of the range of the douglas fir. Logging used to be the dominant industry in this area; nowadays, because all the big trees have been cut down, logging is on the decline, but it's still important. The 90s were particularly rough on the douglas firs in this area; we have had massive die-offs. On my own land, I have lost about 20% of my douglas firs; I am lucky because I have a creek running through my land that sustains most of them. Their natural replacement in this area is the ponderosa pine, and we are planting ponderosas as part of our reforestation efforts. But these trees take 50 years to come to full size, and the douglas firs are dying off faster than that. As a consequence, my region is undergoing net deforestation, despite intensive efforts to plant seedlings. How much is that worth?

Now let's talk about the political costs of global warming. Some people will be winners, and some people will be losers, although there will likely be more losers than winners. So what kind of political stresses will arise from all this? What happens when we realize that global warming is costing us dearly, and we ask China to cut back on its gigantic CO2 emissions, and they give us the finger? How many billions of dollars will we end up spending on military expenditures to address the increased political tensions arising from all this?

But hey, cutting back on CO2 emissions right now could cost us billions of dollars; we need to save our money, right?

You are on the dark mysterious road of speculation. You assume that net result of change is negative. As I have said before our ability to adapt and create new technology wipes out the assumed political costs. Part of the reason the Southeastern US is having a population explosion is because of affordable AC. Sixty years ago that simply was not the case. 100 hundred years ago I am sure most people would agree some areas of the South would always be "too warm" to live in. Technology has changed the perception, as it will with this recent day gloom.

I don't assume that change is negative, I present a lengthy explanation of the likelihood that temperature change is more expensive than temperature stability. If you have objections to the points I make, then by all means present your objections. The sad truth is that we simply cannot come up with a budget of benefit and cost for global warming because it's all going to be localized. Yes, there might be increased rain in the American midwest -- but there were also be higher soil temperatures, which will yield higher evaporation rates. Which will dominate? It's impossible to say. However, there are definitely some problem areas in which temperature change will yield higher costs.

I don't doubt our ability to adapt and create new technology, but I think it glib to airily brush aside all problems with technological optimism. Some technologies, such as fusion power and artificial intelligence, have proven to be far more difficult than originally imagined. Others, such as integrated circuitry, have proven to be surprisingly useful. Yes, I too believe that technology will do great things for us -- but I don't believe that technology is a panacea, and I don't dismiss all future problems with the claim that technology will solve them for us.

Which is based on speculation that the change will have a negetive impact. Your explanation is concentrated on every negative aspect imaginable.



This goes back into what I just stated in the above and also into the facts I presented here.



That pretty much sums up this aspect of the debate. Evidence suggests that it is not clear whether US crops will be adversely affected by climate change. In this case, it does not make sense to make drastic policy changes. For energy reasons alone the US should look at alternatives, but this is not because of Global Warming. Our dependency on foreign sources of energy and our lack of an energy policy over the last 25 years necessitates the need for new ideas on cleaner, cheaper energy.

nemov


Thank you! You cited some source material that it is productive to talk about. To the limits of its assumptions, this study would appear to be solid. However, it is important to realize what those limits are. First, it was limited by being confined to the United States. All projections show the worst effects of temperature increases on yields to be in lower latitude areas where the majority of the world's people live and the majority of food is grown, so this study is hardly comprehensive in predicting the impact on the world's food supply. Secondly, the study doesn't include the impact of ozone that is projected to rise along with GW gases. The recent field studies that showed yield declines included simulated increases in ozone. Thirdly, the study doesn't include the impacts of projected extreme weather events on U.S. crop yields. The lead author and two of the other authors of this report, together with others, authored another report in 2002 that tried to assess the likely consequences. See Excess Precipitation.



It is important to consider all of these studies together and that is what the IPCC is structured to do. Instead many critics want to broadcast every study that has the slightest implication that the consensus view is wrong or that adapting to major temperature change is feasible. (We all agree that some adaptation is possible, we are already in the process).

What I conclude is that there is a real risk of greatly increased mass starvation if we let climate change precede unchecked. I would pose the following questions to consider:
Is arable land increasing or decreasing in the world?
Is the irrigated area increasing of decreasing?
Are major aquifers being depleted?
Are fishers collapsing?
Is world population increasing?
Are yields stabilizing as limits of hybrids and fertilization are reached?

I do find a ray of hope in things like this. However, I wouldn't stake the future on its success.

Well, the US is where I live and is where my policy will be made. If you look into some of the most impoverished nations on earth, they are also the most densely populated in some cases. Climate change is the least of their concerns when considering that they are in poverty now. Being unable to adapt with any kind of changes is their first concern. That is why other avenues of development are more beneficial to those areas (free trade, education, etc.).

For developed world (i.e. the US) the approaching changes can be managed. For the undeveloped world there a myriad of different issues that need addressing.

All the questions you have posed are worthy of debate. Much has been written about limited resources, but it unclear when (if ever) the human race will reach that point. Just because there is concern over climate change does not mean those concerns are any more founded than they were before.

Change always affects those that cannot adopt the worst. People that lose their jobs due to US manufacturing job losses are at a disadvantage when compared to highly educated workforce. Much like the American farmer losing out to the industrial revolution these present difficult choices for those affected. However, these changes are ultimately met and progress is made.

Actually, it's not speculation; it's the second law of thermodynamics. You are arguing that change is neutral in its impact, that the positive consequences can balance out the negative consequences. That assumption runs afoul of 2nd Thermo, which says that the entropy of any system left to itself will always increase or (in extremely rare situations) stay the same. For example, it is theoretically possible that any given earthquake could yield positive results by knocking down an old obsolete freeway overpass and then bouncing the chunks around in such a way that they spontaneously reassemble into a brand new, better freeway overpass. But 2nd Thermo says that this kind of thing is extremely rare; whenever you jiggle around a complicated system, things are likely to become less organized. The human-biosphere system is extremely complicated; if we jiggle it around, 2nd Thermo says that the entropy of the system will increase -- that it will become more broken, more disorganized.

More than two millenia ago, Thucydides wrote, "It was the growing power of Athens, and the fear that this caused in Sparta, that made war inevitable." Change can be very dangerous.

Are you saying that the changes in the US will be negative, or that you don't know, or that you know the 2nd law of Thermo?

I do not believe and I have not said that change is neutral, but I do not believe this change based on the evidence I have seen is the kind of threat many would like us to believe. The easy answer to this is that change is inevitable. We do not know how the changes will affect us (negative/positive) which means we will address and adapt when they come.

2nd Thermo says the overall effect of such change will be increased disorderliness in the system as a whole. From the point of view of civilization, disorderliness is a bad thing. Buildings are orderly; piles of rubble are disorderly. Farms are orderly; barren wastelands are disorderly.


This is a turgid statement. You acknowledge that change is bad, but also believe that there is no evidence that temperature change constitutes a threat. So you expect bad results, but don't see evidence for them?


Here you seem to be saying that we don't know whether the changes will be on balance positive or negative. This would contradict your earlier statement. Please clarify.

Couldn't one make the argument that the increase in disorderliness while negative in the short term can be positive in the long term? Or perhaps i can say that while the disorderliness is negative that is is inherently necessary, via Dawinism and the theory of natural selection. The strong will survive while the weak don't.

If i am understanding Nemov correctly, he is asserting that climate change is inevitable and is a natural occurrence that happens every so often to this planet. I agree with this. I don't think anyone is disputing whether or not the global climate changes or whether it is a threat...the only thing that is being disputed is that humanity has a direct affect on this change. The evidence i have seen shows that humanity has a minimal if any affect on the grand scheme of things. If we look at the history of the earth's temperature as i provided in an ealier post...we can clearly see that there have been fluctuating periods of hot and cold temperatures and this is without any human interference. We are coming off an ice age where the temperature was very cold...it is only logical that the earth would be heating up.

Yes, inasmuch as there is negentropy coming into the system in the form of sunlight. So climate changes, things get worse, and then we get to work and eventually things improve. Of course, we end up worse off in the long run than if we had avoided the global warming in the first place.


If you want to dispute that with the IPCC, the majority of climatologists, and most scientific organizations, go ahead.

But thats the illusion Erasmussimo! It can't be avoided. It's going to happen. With or without human interference global warming is going to happen because it is a natural occurrence of the planet. Again, if we look at the history of the earth and its climate changes...there have been periods where its been very hot and very cold. There was zero human interference for millions of years. But now, after only 150 or so years of extra gases in the air...the entire ecosystem will be destroyed?

Since global warming is unavoidable, it makes more sense to spend money aimed at adapting to the changes rather than trying to prevent the inevitable.



It wouldn't be the first time

On this point, I and the majority of climatologists disagree with you. The general conclusion is that global warming is anthropogenic. I'll be happy to explain why this is the case, to teach you the science behind it, and to explain why some of the explanations bandied about by the deniers are wrong, but I won't argue with you on this point. As far as I'm concerned, this is a question for debate by experts, not tyros.

If you won't argue on the point then you are on the wrong site. I may not be an expert on the issue like you but that doesnt meant i dont comprehend it well enough.

Look i understand the science behind greenhouse gases and the belief that human interference causes the Earth to warm. But you still dance around the point that global warming is a natural occurrence of the planet. We just came off an ice age a few thousands years ago. There was a 'little ice age' from 1500AD-1700AD...of course the earth getting warmer. Again, if you look at the history of the Earth..most of it is spent in periods where the temperature was that of the dinosaurs. Our temperature right now is the exception. All i want you to do is explain to me why there was such temperature fluctuations before humans even existed and why it is completely out of the realm of possibility that our current warming trend is attributed to that natural fluctuation.

I'd be happy to. Paleoclimatology, the field that addresses these concerns, is a young field. While many hypotheses have been offered to explain climatological temperature changes over the earth's history, no firm conclusions can be drawn. There are three broad groups of explanations, and most paleoclimatologists consider that all three played a role at various times.

The first of these is astronomical. One version of this relies on slight changes in the earth's orbit, and three such cycles have been demonstrated to have had an effect on global mean temperatures: a 21,000 year cycle, a 43,000 year cycle, and a 100,000 year cycle. Another hypothesis is that we drifted through clouds of interstellar gas that obscured some of the sunlight reaching earth; this is no longer a major hypothesis. A third hypothesis concerns internal variation in the sun's output. This is most often associated with the 11-year sunspot cycle; some claims have been made for longer cycles but these run afoul of what we know about stellar structure (stellar interiors don't oscillate fast).

The second group of hypotheses are based on tectonics. As the earth's continents move around, they dramatically change airflow in the atmosphere and ocean currents, which in turn play a major role in distributing heat around the globe. It has been demonstrated, for example, that the recent rise of the Tibetan plateau played a major role in the establishment of the Indian Ocean monsoon cycle. There are also claims that periods of increased vulcanism may have impacted climate, but the short settling times for upper-atmospheric particulates have cast doubt on such claims.

The upshot of all this is that, although we know many of the factors that went into past climate changes, we can't really say for sure what factors played the largest roles in any particular climate change. The primary problem here is not lack of theory but lack of data. After all, it's pretty difficult getting good temperature data from millions of years ago, and when you don't even have a good idea of where the continents were, it gets even more difficult.

We do have some limited sets of good data. For example, the Russians took some excellent ice core data from their Vostok station; I downloaded it and ran a quickie analysis. The data covers the last 400,000 years, in variable time resolutions because of compression of the ice. At the surface, they are able to sample temperature every 30 years; at the bottom of the core, every 630 years. All in all the average temperature change between intervals is about 0.3 degrees Kelvin; the largest is 2.4 degrees Kelvin. This last value, however, looks like bad data to me because it's surrounded by compensating values, and it's way out of the statistical distribution. In terms of overall temperature change, the steepest large-scale temperature change was an increase of 8 degrees Kelvin over about 7,000 years; this was about 330,000 years ago. That comes to about 1.1 degree per millenium. Smaller-scale temperature changes of up to 10 degrees per millenium do occur, and there are a few oddball datapoints indicating temperature changes even higher than this -- but most are given away as outliers due to the dramatically different, often compensating neighboring values.

This brings us to the most powerful argument against the notion that current warming trends are natural: the rate of change is much higher than anything observed historically. Right now, some predictions indicate that we'll be seeing temperature changes of 50 degrees per millenium. That's just not in the ballpark for natural change.

This is a complicated subject and I have simplified the story to fit it into this short (!) piece. But it provides a good starting point. Any questions?

I am not sure how to answer this because my statements have been very clear. Change is not always negative. Change can be bad, it can be good, but in this case, it is unpredictable. From the studies I have cited it is not clear the change will have a negative impact on farming in the US, and it may in fact be positive. This is after years of discussion about how crop yields will be decimated by climate change in the US. Hence, there is “no evidence that this change constitutes a threat” to crop yields in the US.



Please feel free to read my words again. There is nothing there to clarify. Climate change is unpredictable in relation to how it affects the Earth (as the crop yield study shows).

OK, I can agree that, with respect to any particular topic, it is more or less difficult to predict the gains versus losses arising from temperature increases. 2nd Thermo, however, provides us with a strong argument that the net results will be negative.

Have you any questions regarding paleoclimatology?

nemov


I don't think any development avenue can be more beneficial than an assured supply of food. Even if food is available for trade most farmers in the developing world lack any resources with which to purchase it. If their crops fail that's it! And it is not certain that food will be available for trade or aid. As I stated before, the world consumed more grains than in produced in 2001, 2002, and 2003 and barely broke even in 2004. (See Grain Stocks). Things don't look all that good this year, at least not in the U.S., a major exporter. See Drought Article.

I think it is unreasonably selfish to confine your concern to the U.S. Afterall, with 4% of the world's population we are emitting 25% of all carbon dioxide and probably a larger percentage of other greenhouse gases. From a selfish point of view, we also have an interest in a stable world. Some projections show harvests in Pakistan declining by 50%. Imagine the chaos that might produce in a nuclear armed state!

However, if we take the debate on your terms and confine it to U.S. harvests, the situation is still of concern. I demonstrated to you that even some of the authors of the study you cited also reported less optimistic results when they factored in damage from heavy precipitation. As stated in their report, they didn't include hail and some other possible increased weather damage. Nor did they include projections of increased ground level ozone. Earlier I cited one study with this affect included on rice production in the Philippines showing 10% reductions in yield per 1 degree C temperature increase. Here is one focussed on U.S. crops. Your argument also totally ignores the studies based on historical temperature variations versus yields that I cited at the beginning of this discussion.

I would agree that there is some uncertainty about the impact of climate change on crop yields within the United States. (Although I think the balance of the evidence indicates declining yields). However, to be willing to gamble on the outcome to such a fundamental question as world food supplies is beyond me.

On the other hand, I would accept your endorsement of a move toward energy efficiency and renewables as a sufficient response until the uncertainties are reduced and current impacts become clear. I accept your reservation that you accept these goals because we need to do so from an energy policy perspective anyway and would not endorse them as a response to GW. However, I would add that from my perspective this transition needs to be promoted with diligence and not hampered with boondoggle legislation like the energy bill currently under consideration in the House.

TedN5, very well written. Obviously, we can agree to disagree and most of our disagreement here comes from our political ideology. I am always skeptical of government intervention in any avenue. Sometimes intervention is necessary, look at the effect on pollution the EPA regulations have achieved in the US. Over time if the weather does indeed become worse the human race will adapt and make the necessary changes (like this).

This is the very point I was pondering as I re-read this thread! I noticed that people who tend to oppose government intervention on social issues (almost to the person) seem to find ways to disagree with the science behind GW. This does not compute!

Einstein too, made the mistake of inserting a personal belief into a his scientific process and ended up making a 20 year mistake. He added a "cosmological constant" into his equation because he didn't believe the universe should be expanding as he found it to be. Edwin Hubble made him eat crow on that issue....

Just because you disagree with the politics of an issue SHOULD not be a reason to disagree with the science of it. The situation, as laid out by most climatologists, seems to be dire. The article Nemov provided lacked scientific credential, used quotes out of context and had a clear political agenda. That was my first hint that we were really having a political discussion.
I found the article to be horribly dishonest in its presentation and purpose.
A true conservative, as I see it, would look at the overwhelming evidence and argue that the problem (and there is one) must be resolved by private interests and technological ingenuity.
A conservative would try to find a way to make money and make our world better.

If you don't like the idea of the government paying out of pocket for a fix then perhaps we can suggest wats that the government can make it profitable for companies to do so. Our system is maddening to me because we aren't socialist and we aren't capitalist either. There is clearly a market for efficient energy and yet the current energy conglomerates are paying Washington to keep the status quo. Why not rely on cappitalism? What ever happpened to competition?

If our energy industry were not the inbred stepchild of the government that it is this thread would not exist. Companies would be pushing eachother in the battle for more efficient technology because we consumers are sick of paying through our noses for energy that poisons us. There IS a market for clean, renewable energy. If the government would simply level the playing field by ending its intimate relationship with "big energy" and possibly provide incentives for innovating companies we would be heading in the right direction.

Global Warming is certainly a serious issue. The boundless complexity of our ecosystem makes it nearly impossible to predict the outcome. (Our best computers and models can't even predict, with certainty, what will happpen when weather fronts meet) It is folly to sit back and wait until computers are fast enough and models accurate enough to predict whether or not we will kill ourselves off.

Nemov and La Herring Rouge, it isn't as if there wasn't already widespread intervension in energy markets. Granted there are some subsidies that marginally benefit alternatives but the overwhelming bulk go to fossil fuels. The overall effect is to make it more difficult for alternatives to become established in the market. Here is one discussion from the RMI study Winning the Oil End Game.



I again recommend the whole study.

La Herring Rouge, I appreciate your participation here, but aside from your disagreement with me I don't understand your first paragraph. While the generalization is correct I would argue those that are in favor of government intervention on social issues believe global warming is a threat to the human race. It has been like that long before there was a so-called “scientific consensus.” Just like evangelicals that are always craving some kind of end of the world scenario environmental extremists are always talking about some kind of calamity. There may be some merit to Global Warming, but you have to concede there have been a lot of “the world is going to end theories” that seemed well founded at the time that turned out to be bogus.

Science has come a long way in a hundred years, but I am not ready to say they are infallible or that they rise above groupthink.

My second comment is I am not sure what article you are lambasting. This has been a long debate and the only real scientific article I have posted (if my member serves) is this. The situation presented by many alarmists is dire, but until we start seeing some real adverse changes the jury is out. I thought liberals were supposed to question everything?

La Herring Rouge


I think you underestimate the power a world view has on the way we react to evidence, even scientific evidence. This is particularly true of a field as complex as climate change where a few respected scientists like Richard Lindzen still remain unconvinced and where large uncertainties still exist. I do think the skeptics should realize that the uncertainties may mean more rather than less global warming and that we may not have time to react unless we begin now.

I did like your comment on Einstein, I was going to post something similar with respect to Lindzen, who has accused consensus climate scientist of being like a religious cult. Spencer Weart, in his book The Discovery of Global Warming (also availabe on line here), says of Richard Lindzen's iris theory about whether water vapor is a positive or negative feedback:



This sounds a lot like Einstein's cosmological constant advanced to preserve his own semi-religious view of a stable universe, don't you think? I think both are good examples of just how powerful preconceived views of things can effect even how great scientists process information. Let's hope Lindzen's theory proves as useful in another form as the cosmological constant has in modern cosmology.

Let's not get into the habit of dismissing a good idea because there are nut cases who take it too far. Yes, the sky-is-falling crowd has seized upong global warming and said some silly things about it -- but then, there are plenty of die-hard anti-environmental folk who have made ridiculous claims, too. The substance that we need to focus on is the likelihood of temperature increases over the next century of around 5 degrees Fahrenheit. That will not spell the end of the world. But it will require adjustments on our part that will surely cost us billions, and possibly trillions of dollars.

Ok, being the prudent person i am...i did some further research into the matter. And i am glad that i did becuase now i am almost convinced that this global warming mumbo jumbo is a lot of hot air (excuse the pun)

First, you mentioned the Vostok Ice Core. Well here is a graph of the data i am assuming you saw. I am no graph expert...but it looks to me that the temperature has varied back and forth between hot and cold temperatures for thousands of years...

But moving on to other data which i found quite interesting. First...the common talking point is that CO2 emissions by industrialized nations is what is heating the Earth and causing the greenhouse effect. Of course, CO2 (3% of atmosphere) isn't even one of the top greenhouse gases... water vapor takes the cake. What i find is that historically...CO2 has risen in the atmosphere as a result of a rise in temperature. And obviously this makes loads of sense. As the temperature of the earth naturally rises...the growth of plant life on the planet also increases emitting much more CO2 into the atmosphere. I mean for the CO2 to be greatly affecting temperature it would have to be accepted that during a cold period of climate which is a lot less likely to encourage growth of plants, that the CO2 emitted caused the temperature to rise.

The climate models used by computers are inherently flawed because they disregard the effects of the sun which is the most influential natural cause of climate change. The cyclical change in radiation emissions from the sun has a near direct effect on the climate of the Earth. The models are further innacurate because the stations in which are tested are mostly in urban areas. The climate change in urban areas are much more significant than that of rural areas because of the land is being used up for industrial and commercial purposes. Just putting down a sidewalk of cement makes that area warmer than if it was dirt.

The fact of the matter (as i see it) is that this is not an abnormal rate of change in the climate when compared to geological models in the past milennia. There are places on the earth where it has grown warmer such as in the Arctic and there are places where it has actually grown cooler like in Antartica. There are places the sea level has risen and there are places the sea level has gone down. There is no conclusive evidence that shows that human interference with gas emissions effect global climate change at any level close to that of natural causes.

After all my research the most helpful was a video from Candian Professors titled "Climate Catastrophe Cancelled: What You're Not Being Told About the Science of Climate Change"

Let's step through your stuff:


Yes, it has varied back and forth for thousands of years. So what? That has absolutely zero relevance to the issue of anthropogenic global warming. I directly addressed this point in my post and pointed out that it was the rate of change, not the net magnitude of change, that differentiates anthropogenic global warming from natural temperature variation. Look at that graph again. Look at the time scales. If you stretch the graph horizontally to make the last 100 years cover, say, one millimeter, then the graph will be about 13 feet long. All those up and down temperature swings you see will show up as gentle sweeps, slowly inching up or down -- but the last 100 years will look like a sharp vertical line shooting upward. That's the proof.


Yes, water vapor is a constant factor in all this. So are mountains, lakes, and beaches. But the water vapor isn't changing; the CO2 is. There can be 3 zillion constant factors and one variable one, and all those constant factors don't prevent the variable one from changing the results.


You have it exactly backwards. Plants do not expire CO2, they inspire and sequester it. They take CO2 out of the atmosphere, strip out the carbon and use it to build their cells, and release O2. The causality is not (increased temperature) --> (more plant life) --> (more CO2). It runs the other way: more CO2 directly results in both higher temperatures and faster plant growth.


I see. Please provide us with the numbers to back up your assertions. What is the percentage change in incoming solar radiation as a function of time? Calculate the effect of this percentage change on the global mean temperature. You may use a simple blackbody radiation model for this calculation. Can you demonstrate that your proposed model has any quantitative significance?


This is a flat lie. The temperature data used in climate modelling is vast. They rely on all manner of data, including satellite data, ocean temperatures (both surface and subsurface), air temperatures (at a variety of altitudes). You're saying that the only data these models use is a handful of numbers taken from urban temperature gauges; that is absurd, ridiculous, ignorant, foolish, risible...


Then you're not looking at the data. Take another look at the Vostok ice core data, stretch the horizontal scale to make the last century readable, and add the temperature increase of the last century -- then tell me that it's perfectly normal.


It has grown cooler in Antartica? Then why has a chunk of ice sheet the size of Rhode Island broken off and started melting away? Show me your data.


It doesn't work that way. Sea level is geophysically universal. Show me your data.


That's your conclusion; the majority of climatologists disagree.

I'm sorry Erasmussimo but "stretching" a graph to get a better visual is in no way a means to get good empirical data. Now if you said let's take it by a numbers that would work much better. Is there a numeric chart where this chart came from? I would like to see those numbers instead of a graph.

Agreed, relying on the visual only does not provide a definitive analysis of the data. I downloaded the data and popped it into a spreadsheet for a quickie analysis. You can find it here. Try it out yourself. For each pair of data points, calculate rate of change of temperature, then look at the distribution of these values. There are a few outliers that can be rejected after examination of the raw data. But looking at them as a group makes the current rate of change jump out at you.

If you are using Geoscientist Michael Mann's famous "Hockey Stick Model" for your assertion about the sharp change in temperature in the past