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Posted

Alright, this thread is specifically designed to address all of SkepticLance's, and other global warming "skeptics" claims and/or misunderstandings. Here, they can present their position, and any evidence/data/references that they might have to support their position. While we can go on and either verify or debunk their claims. This is an effort to keep these types of fights all over the place, and more specifically to keep politics out of it. It's time to settle this issue once and for all.

 

Hopefully, this thread will become a comprehensive compendium of why the so-called global warming skeptics are wrong.

 

Well, with that out of the way, begin...

 

So, to start with, as we keep saying in just about every other thread on this subject, average global temperatures are increasing at an exponential rate, and is predicted to climb to about 3 C or more by 2100 according to our climate models.

 

The models so far have been accurate in predicting current climate change, which you can view on this link: http://www.logicalscience.com/skeptic_arguments/models-dont-work.html

 

For more specific quotes:

* Models predict an energy imbalance between incoming sunlight and outgoing infrared radiation' date=' which has been detected;

* Models predict sharp and short-lived cooling of a few tenths of a degree in the event of large volcanic eruptions, and Mount Pinatubo confirmed this; (Figure 7)

* Models predict an amplification of warming trends in the Arctic region, and this is indeed happening; (Figure 8)

[/quote']

 

So, there you have it.

 

 

Now, of course, there are some here that disagree, and so they are given the chance to either prove us wrong or that there really is something to the climate models we are missing.

 

And if anyone would like to add anything else in support of our position here, you can do so, and please do so, so that we can settle this issue.

Posted

The question isn't whether global warming is happening or not; we know that it is, we can mesure the temperature rising over time.

Also, global temperature has risen and dropped many times throughout history.

The debate is one of 'cause'

Whether or not burning fosil fuels is actually causing the temperature to fluctuate, or whether this fluctuation is entirely natural and is not caused or accelerated by burning fossil fuels.

 

One of the main arguments is whether increased CO2 causes temperature increase, or whether teperature increase causes CO2.

 

Either

CO2 has a much higher thermal absorbtion rate than nitrogen or oxygen, thus CO2 rleased into the atmosphere will cause it to get hotter.

 

Or

As sunlight hits the ocean, it releases CO2 into the atmosphere; increasing the overall level of CO2.

 

Either.

All burning of fossil fuels is effectively carbon neutral, as the carbon within coal, was originaly part of a tree, which got it's carbon from the air when it was growing, thus by burning it, one is simply putting the carbon back into the atmosphere where it came from millions of years ago.

 

Or,

by burning fossil fuel, this carbon cycle has been interfered with, putting carbon into the air at a faster rate than nature intended.

 

Questions:

Are humans capable of producing carbon in sufficient quantities to have and effect on the carbon cycle, enough to change global temperature?

 

Is even a small amount of man made CO2 enough to tip the scales, into a cascade sequence of global warming?

 

Is global warming bad for the Earth in general? (It's recovered from worse)

Is global warming just bad for human survival? (how much does it affest us?)

If we stopped using fossil fuels tomorrow, what would happen to the temperature?

Could we adapt to a hotter Earth?

How much affect does the fluctuating sun have on Earth's temperature?

If it is a conspiricy, who stands to gain from it, if anyone.

If it is not a conspiricy, could governments do more?

Conspiricy or not, fossil fuels are running out, so any effort toward renewable energy must be positive.

Do the general public realy understand science and climatology? enough to make decisions about it. If they do, why do they buy hybrid cars?

 

My own personal position is 'On the fence' (A fence made from sustainable sources of course) As i've see evidence from both sides of the argument.

Posted

There is no debate regarding cause among people who actually study this for a living. The debate is all among people who know little more than news clips.

 

CO2 absolutely causes warming.

We humans are absolutely adding CO2 to the atmosphere.

Posted
There is no debate regarding cause among people who actually study this for a living. The debate is all among people who know little more than news clips.

 

 

Yeah, I know. The reason for this thread is so that someone like SkepticLance. doesn't go off and pollute the other threads that are intended for a legitimate scientific discussion about these sort of issues; in other words, this thread is intended so that we don't have to endure 11+ pages of repetitive crap on otherwise good threads. Just think of this as quarantine for the deniers ;) .

Posted

To Lockheed

 

When you use words like pollute, you are committing an ad hominem attack. Stop it!

 

For others who don't know what he is talking about, it would appear that he and iNow got upset because they did not like my sceptical approach to their predictions of future doom.

 

There is no dispute about the basic principle of global warming, or its cause. However, when it was suggested that we would get a 3 Celsius warming in the near future, I suggested that was unlikely. Not impossible - just unlikely. We did not define 'near future', and I took it to mean just a few decades.

 

I am not impressed by global climate models, which are still struggling with a number of unknowns. The one recently publicised is the difficulty of accounting for the effects of variable cloud formation. This suggests that the long term reliability and accuracy of these computer models is questionable.

 

However, we do have one clear cut, reasonably long term trend. The past 30 years represent the first clear cut simple case where temperature rise is operating in response to just anthropogenic greenhouse gases, and there is little influence from other factors. Over this 30 year period, there is a steady warming of 0.15 to 0.2 Celsius per decade, and a total of 0.5 C warming for the whole 30 year period. The warming fluctuates up and down on an annual level, but over the whole 30 years can be approximated as a linear event.

 

I am not suggesting that this means future warming must also be linear. However, unless some major change occurs ( such as major change in solar output), the deviations from the current trend should not be dramatic. If we assume that the warming stays close to the present trend, then warming by 2100 will be about 1.5 C. Of course, we cannot know exactly what the warming will be.

 

By the year 2100, the world may have warmed by any amount from 0 Celsius to X Celsius. I have tried to point out the uncertainty of predictions, but get shouted down.

 

Now, anyone else.

Posted

The climate models for temperature prediction are "accurate" because they are updated continually. As time progresses the model is updated to reflect the true temperature increases. The first temperature models produced during the 80s I believe had the temperatures being 5 C higher by the year 2000!!! That of course didn't happen. Basically, the models have limited range of accurate prediction since the only reason the models track with historic temperatures is because the models are constantly updated.

Posted
TI have tried to point out the uncertainty of predictions, but get shouted down.

 

i think part of the problem is that these uncertainties are generally factored into the models.

 

i.e., we may not know the precise effects of factor x, buy we can make an informed estimate at the maximum/minimum likely effects of factor x, and thus still have accurate models. fair one, they're accurate by dint of being less specific (larger margin of error), but they're not useless just because we don't fully understand every single factor.

Posted

Hopefully, this thread will become a comprehensive compendium of why the so-called global warming skeptics are wrong.

 

Glad to see that you are starting this off in such an unbiased and impartial way. I’m also happy to see that you are a hope filled person. Just curious, but what branch of science explores the topic of hope?

Posted

Let me see if I can kick off this thread with a question, and see if we can get a good debate going without the emotion and hysteria.

 

I am presenting a hypothesis.

 

People designing global climate models on their supercomputers are not able to adequately simulate the process of cloud formation. This leads to serious problems, making long term predictions unreliable and inaccurate.

 

In order to support this hypothesis, I am presenting the following reference, which discusses the efforts modellers are undertaking to try to overcome this problem.

 

http://www.innovations-report.de/html/berichte/umwelt_naturschutz/bericht-37677.html

 

Question :

Does my reference support my hypothesis?

Any other comments?

Posted
People designing global climate models on their supercomputers are not able to adequately simulate the process of cloud formation. This leads to serious problems, making long term predictions unreliable and inaccurate.

 

i'd agree that cloud formation is not accurately simulated. however, from the IPCC report (4, 'phisical basis', FAQ, http://www.ipcc.ch/ipccreports/ar4-wg1.htm):

 

There is considerable confidence that climate models provide

credible quantitative estimates of future climate change, particularly

at continental scales and above. This confidence comes from the

foundation of the models in accepted physical principles and from

their ability to reproduce observed features of current climate and

past climate changes. Confidence in model estimates is higher

for some climate variables (e.g., temperature) than for others

(e.g., precipitation)[note: they include cloud cover under 'precipitation']. Over several decades of development, models

have consistently provided a robust and unambiguous picture of

significant climate warming in response to increasing greenhouse

gases.

 

[...]

 

Significant uncertainties, in particular, are associated with the

representation of clouds, and in the resulting cloud responses

to climate change. Consequently, models continue to display a

substantial range of global temperature change in response to

specified greenhouse gas forcing (see Chapter 10). Despite such

uncertainties, however, models are unanimous in their prediction of substantial climate warming under greenhouse gas in-

creases, and this warming is of a magnitude consistent with

independent estimates derived from other sources, such as from

observed climate changes and past climate reconstructions.

 

[...]

 

Models continue to have significant limitations,

such as in their representation of clouds, which lead to uncer-

tainties in the magnitude and timing, as well as regional details,

of predicted climate change. Nevertheless, over several decades

of model development, they have consistently provided a robust

and unambiguous picture of significant climate warming in re-

sponse to increasing greenhouse gases.

 

so, in summary: yes a problem, and, yes, the precision and accuracy of the predictions suffer as a result; but no, not a problem of such magnitude that it cannot be worked around, the uncertainty included in the predictions, and meaningful and reliable predictions still made.

 

I'd reword it:

 

"""People designing global climate models on their supercomputers are not able to accurately simulate the process of cloud formation. This leads to problems, making long term predictions less accurate than they would otherwize be."""

 

btw: as i read it, the uncertainty with reguards to cloud-cover contributes hugely to the margins of error that the IPCC predictions have.

Posted

From what I've read, it's a far more significant problem in regional climate models, because the large "grid" size can ignore local effects that are below that resolution.

Posted

To Dak

 

Thank you for that reply. It was intelliegent and researched. A very good example of how such a debate should be continued.

 

I agree that warming will most probably continue for some time to come, and will be significant. I come to that from a slightly different angle, in that the warming in response to greenhouse gas increase over the past 30 years has been steady. This means a long term trend, and long term trends have been shown by history to have a tendency to continue.

 

Does anyone think that my suspicion of the long term accuracy of global climate models is without foundation?

Posted
I agree that warming will most probably continue for some time to come, and will be significant. I come to that from a slightly different angle, in that the warming in response to greenhouse gas increase over the past 30 years has been steady. This means a long term trend, and long term trends have been shown by history to have a tendency to continue.

 

And this is where you will find disagreement, because does not have a solid basis in science or math, and we've been through all of this. "long term trends have been shown by history to have a tendency to continue" is self-fulfilling; if you have a long-term linear process then you have a long-term linear process. But you haven't established that this trend is actually linear. 30 years is arbitrary; there is an obvious reduction in slope prior to that. The justification that you can only use that range because it's clearly dominated by CO2 is a circular argument in the absence of supporting information. The use of a linear fit is artificial, since nonlinear functions will exhibit linear behavior if limited data is used. The CO2 driving term is increasing exponentially.

Posted

Swansont

 

Please read the following, since you do not appear to have read my earlier postings.

 

I have said before so many times. I am not claiming a linear extrapolation. Just that, the past 30 years have approximated linear, which makes it less likely that a major departure will occur in the near future.

 

And yes. Long term trends can be and have been tested scientifically. It is simple. You make a prediction from a long term trend and see if it happens. Often, it does. At least a lot more often than predictions from other methods. Historically, projecting long term trends is a more reliable method of making predictions than almost any other. Of course, any prediction is very likely to fail, including those from long term trends, and from computer models.

 

And no. 30 years is NOT arbitrary, as I have explained to you many times. It is the ONLY part of recent history in which global temperature change has occurred clearly as a result of greenhouse gas increase without some other factor dominating.

 

For 30 years we had steady warming to a total of 0.5 C in line with the steady CO2 growth. For the 35 years before that we had a net cooling of 0.2 C, which makes it hard to talk about global warming for THAT period. For the 30 years before that, we had warming of 0.4C, but with only trivial CO2 growth, making a cause and effect conclusion rather shaky. And for the 30 years before THAT, we had cooling, associated with almost exactly the same trivial CO2 growth associated with the 0.4 C warming.

 

ONLY the last 30 years shows a clear cut relationship between CO2 and warming. Do you get it now? Choosing 30 years is far from arbitrary. It is the ONLY time period with a clear relationship between CO2 and warming.

Posted

To iNow

 

Long term?

Lousy question. I know this is a totally unsatisfactory answer, but it is : "It all depends."

 

In geology, long term means hundreds of millions of years. In human paleoanthropology, it is hundreds of thousands. In human history, it is thousands. In politics, it has been said that a week is a long time.

 

In other words, it is all relative.

 

However, in terms of our debate, that is pure semantics, and a diversion from anything meaningful. I have used the figure of 30 years, for very good reason. Perhaps you may care to relate to that.

Posted

In that case, I will read your post to mean that "long term" equals 1 month. After all, it was a lousy question, and "it's all relative."

 

So, here's what you just said:

 

I have said before so many times. I am not claiming a linear extrapolation. Just that, the past 30 years have approximated linear, which makes it less likely that a major departure will occur in the near future.

 

And yes. ONE MONTH trends can be and have been tested scientifically. It is simple. You make a prediction from a ONE MONTH trend and see if it happens. Often, it does. At least a lot more often than predictions from other methods. Historically, projecting ONE MONTH trends is a more reliable method of making predictions than almost any other. Of course, any prediction is very likely to fail, including those from ONE MONTH trends, and from computer models.

 

 

If that's not what you meant, you could easily clarify how long you mean by "long term" instead of evading the original question to you.

 

 

 

To this point:

It is the ONLY time period with a clear relationship between CO2 and warming.

 

The relationship between CO2 and warming is not time dependent. It is a time independent relationship. Whether it's in the past 30 years or 3,000 years ago, the relationship between CO2 and warming remains the same.

Posted

To iNow

 

Lockheed started this thread with the stated objective of keeping politics out of it. I presume he also meant to keep emotional garbage out also.

Did not take long to degenerate.

 

Please. If you want to continue the debate. Please, give good scientific ideas, or ask good questions.

Posted

Interesting thread (and hypothesis)

 

The current science tells us that climate sensitivity with doubling CO2, at equilibrium, including feedbacks ΔT 2x = 3 K (uncertainty is +1.5 K - 1 K)(IPCC,2007).

 

A few readers have rightly noted the nonlineraity in the slope of the line for temperature increases from pre-industrial out to CO2(2x). Another particular note, which I don't think SkepticLance has accounted for is the thermal lag in the climate system, which delays the response to perturbation of the climate system. In other words, one can assume (e.g. Hansen et al., 2005) that about an additional 0.5 K will be added to the system if CO2 concentrations were held fixed. In short, the system is not now at equilibrium and so Skeptic cannot assume that the temperature response so far is at 380 ppm-like conditions. This must be accounted for in making forecasts for the climate system out to CO2 (2x) because the radiative forcings chart used in the IPCC (2x CO2 = ~4 W/m-2) occurs at equilibrium. In fact, it is likely the ~1.2 C area has already been obtained if we were to keep CO2 levels at 380 ppmv and let the climate system return to equilibrium, so sensitivity for CO2 (2x) around this number is wrong unless one can argue that there is no thermal lag in the climate system.

 

Water vapor feedback is the most important positive feedback in climate models. It is important in itself, but also because it amplifies the effect of every other feedback . Vapor pressure in equilibrium with a water surface increases exponentially with temperature at a rate in accord with Clausius-Clapeyron. If the relative humidity remains about constant as temperature and specific humidity increase, then water vapor greenhouse feedback nearly doubles the sensitivity of climate. The changes in specific humidity, with little change in relative humidity, have been documented recently and in accordance with our understanding.

 

Clouds are a subject of uncertainty (though "unreliable and inaccurate" is indefensible, from real-world observations). First of all, one needs to make a case for a positive feedback from clouds for ΔT 2x = 3 K. Overall, today's models produce cloud feedbacks ranging from approximately neutral to strongly positive because the lower clouds, which control the albedo more than any other kind, get thinner when it gets warmer.

 

The next point is that a lot of work has been done in getting climate sensitivity from both observational and paleoclimatic constraints. Models are useful here, but don't have the only say (ex. http://www.jamstec.go.jp/frcgc/research/d5/jdannan/GRL_sensitivity.pdf ). The argument that models are useless doesn't mean the ice ages or looking at Pinatubo is useless, but the bottom line is that there is not now a physical plausible way of getting a low climate sensitivity. A lot of work has been done (IPCC ch. 9 ) but the range of about 2-4.5 C, and the ability to eliinate really low and really high sensitivity is now there. Uncertanties exist, and the science still needs work, but the policy makers won't be hearing anything new.

 

Chris

Posted
Swansont

 

Please read the following, since you do not appear to have read my earlier postings.

 

I have said before so many times. I am not claiming a linear extrapolation. Just that, the past 30 years have approximated linear, which makes it less likely that a major departure will occur in the near future.

 

Ironic that you would say this because I said nothing about a linear projection in that post.

 

But your statement is self-contradictory. It says basically, that the trend is linear and will continue to be so, which is a linear extrapolation.

 

And yes. Long term trends can be and have been tested scientifically. It is simple. You make a prediction from a long term trend and see if it happens. Often, it does. At least a lot more often than predictions from other methods. Historically, projecting long term trends is a more reliable method of making predictions than almost any other. Of course, any prediction is very likely to fail, including those from long term trends, and from computer models.

 

But you have to justify that 30 years is a long-term, among other things.

 

And no. 30 years is NOT arbitrary, as I have explained to you many times. It is the ONLY part of recent history in which global temperature change has occurred clearly as a result of greenhouse gas increase without some other factor dominating.

 

But how do you justify this, other than saying it's the region that looks more-or-less linear? That's a circular argument. The previous 25 years look linear, too, but with a smaller slope. Why isn't that a case of "clearly CO2 had a smaller effect then?"

 

For 30 years we had steady warming to a total of 0.5 C in line with the steady CO2 growth. For the 35 years before that we had a net cooling of 0.2 C, which makes it hard to talk about global warming for THAT period. For the 30 years before that, we had warming of 0.4C, but with only trivial CO2 growth, making a cause and effect conclusion rather shaky. And for the 30 years before THAT, we had cooling, associated with almost exactly the same trivial CO2 growth associated with the 0.4 C warming.

 

ONLY the last 30 years shows a clear cut relationship between CO2 and warming. Do you get it now? Choosing 30 years is far from arbitrary. It is the ONLY time period with a clear relationship between CO2 and warming.

 

But CO2 was not steady (linear), it was faster, something like an exponential. You've previously claimed that there is a certain relationship between CO2 and temperature to attempt to justify this, but did not provide a citation for it.

 

Again, it's a circular argument. At some point you have to tie it back to some physics to justify your assertions, and you haven't done this.

Posted

To Swansont

 

I do not have an internet citation for the CO2/temperature relationship. I first read it in Patrick Michaels book "Meltdown", which shows how an exponential increase in CO2 leads to a linear increase in temperature (Figure 2.4 on page 16). I have seen in on an internet source, but I did not keep the reference. Perhaps another person can post such a reference?

 

This relationship is accepted climate science and is not controversial. Of course, it depends on how much the CO2 increase is. If there is a very strong curve on the CO2 graph, the temperature increase will also be a curve. However, the past 30 years in the real world saw an exponential growth in CO2 and an approximate linear growth in temperature, as fits this relationship.

 

I would really prefer not to keep arguing the point of using the last 30 years as a reference. A glance at a temperature graph for the last century will give you the answer. Before 1976 the warming or cooling has too many variables. Only after 1976 do we have a simple situation with CO2 increase causing warming, without the complication of other very powerful factors.

 

For example: 1941 to 1976 saw a net cooling. This makes that time period inappropriate as a reference in discussing global warming. The big difference between 1941 to 1976, and 1976 to 2007, is that the earlier time period was very strongly affected by several other factors - mainly sunspot activity change, and possible aerosol pollution change - while 1976 to present shows a simpler picture, with such extraneous factors being only of relatively minor concern. Do you not understand this?

Posted
To Swansont

 

I do not have an internet citation for the CO2/temperature relationship. I first read it in Patrick Michaels book "Meltdown", which shows how an exponential increase in CO2 leads to a linear increase in temperature (Figure 2.4 on page 16). I have seen in on an internet source, but I did not keep the reference. Perhaps another person can post such a reference?

 

This relationship is accepted climate science and is not controversial. Of course, it depends on how much the CO2 increase is. If there is a very strong curve on the CO2 graph, the temperature increase will also be a curve. However, the past 30 years in the real world saw an exponential growth in CO2 and an approximate linear growth in temperature, as fits this relationship.

 

I would really prefer not to keep arguing the point of using the last 30 years as a reference. A glance at a temperature graph for the last century will give you the answer. Before 1976 the warming or cooling has too many variables. Only after 1976 do we have a simple situation with CO2 increase causing warming, without the complication of other very powerful factors.

 

For example: 1941 to 1976 saw a net cooling. This makes that time period inappropriate as a reference in discussing global warming. The big difference between 1941 to 1976, and 1976 to 2007, is that the earlier time period was very strongly affected by several other factors - mainly sunspot activity change, and possible aerosol pollution change - while 1976 to present shows a simpler picture, with such extraneous factors being only of relatively minor concern. Do you not understand this?

 

I understand your claim. What I'm pointing out is that you have not presented any evidence to support it. How do you know that there are no other contributions to warming? Without support, the choice of date is arbitrary.

 

Take your choice of 1941 to 1976. 1941 and the vicinity represents a local peak, from the temperature graph you have previously cited. But 1976 does not represent the end of the cooling; the temperature reaches a minimum around 1950. Solar variation ends by 1960 and is small for several years before that. "1941 to 1976 saw a net cooling" is a true but an inaccurate statement since "1941 to 1950 saw net cooling" better represents the data.

 

Your claim that other forcings were or were not present in the respective periods demand supporting quantitative evidence.

Posted
Yeah, I know. The reason for this thread is so that someone like SkepticLance. doesn't go off and pollute the other threads that are intended for a legitimate scientific discussion about these sort of issues; in other words, this thread is intended so that we don't have to endure 11+ pages of repetitive crap on otherwise good threads. Just think of this as quarantine for the deniers ;) .

 

Now there's a paragraph the other side could never get away with, and a perfect demonstration not only of the fact that this is indeed a political argument, but of which side of this political argument is politically acceptable on this forum, and which side is not.

Posted

To swansont

 

I have no argument with your statement about the 1941 to 1976 period. Sure, the cooling all happened between 1941 and 1950. However, it did not start warming again until 1976. Since we are talking about warming, why include a period of neither warming or cooling? To try to get a picture of current warming, we need a sufficiently long period to average out the year to year fluctuations, and we also need a clear pattern.

 

The 30 year period does it. Yes, there will be other factors besides CO2 affecting temperature. For example : there are several sunspot cycles within that period, which have an impact of about 0.2 C from maximum to minimum activity. However, as far as I know, there are no factors that have a significant overall effect potent enough to change the pattern. If you look at the warming over 30 years, you will see annual fluctuations, but a smoothing out of those fluctuations approximates a straight line.

 

This gives us something to work with. Adding in the net cooling of 1941 to 1976 (even if 1950 to 1976 showed overall net zero change) is simply a complication we can do without.

 

The other thing that is worth bearing in mind is that only the last 50 odd years had sufficient CO2 increase annually to be a major factor in temperature change, with only the last 30 years showing actual warming. So, how can we use temperature change at a time when CO2 increase was trivial to try to ascertain the pattern today, when CO2 increase is substantial?

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