Global Warming

[gene90]

So you do know that more greenhouse gasses would give global warming unless feedback mechanisms disturb the effect.

Possibly. I'd like to look up the earlier papers that originally detailed the greenhouse effect. Maybe you can help by giving cites?

I suspect that after a certain point, further increases in CO2 concentration won't increase temperature. Where that is, I'd like to know, and I'm sure somebody has published it.

You say that the feedback mechanisms necessarily will cancel out the initial human caused effect, so we have nothing to worry about.

No, no, not necessarily. I mean to imply that we don't know.

At the same time you know that nobody fully understand all the feedback phenomena, and consequently nobody is able to predict how nature will respond to the human interruptions. How can you know that nature will reduce the effect? I think it is just as likely that the feedback will amplify the human caused effect!

Well, we have industry running like it is today. Then there is a speculative hypothesis that comes along that claims that an otherwise innocuous gas that we produce a lot of as a necessary consequence of our economy is going to accelerate a warming that is probably going to happen anyway.

There is a political movement that wants us to sign international treaties and force industry to pay billions to make it work.

Well, I think that the quality of the science should be directly proportional to the amount of money we're expected to spend. It isn't. In fact, this stuff is still being argued about. That bothers me a lot.

All we know is that we are changing an important parameter for our climate and consequently we know that something has to change, but we don’t know how things will change.

It's not good to dump billions of tons of CO2 into the environment without knowing the results. I don't want to imply that it is. But that is what drives our way of life. And it's not good to sign multi-billion-dollar international treaties based upon shaky science either. If you want to do that, I would expect you to know exactly what is happening.

So we know we are changing something important, but we don’t know what consequences it will have. Does this sound like responsible behavior?

Philosophically this makes sense, but remember that one of the definitions of a living thing is that it will alter its environment. There is no way around that. Just as climate change is inevitable anyway, so is some tampering with the environment.

Water vapor is also a greenhouse gas, so increased evaporation will also cause increased greenhouse effect and trap more energy within Earth.

Not necessarily, since it is an equilibrium process. The atmosphere can only contain so much water vapor before it condenses into cloud cover. Increased temperatures are more likely to increase cloud cover and precipitation than average humidities.

By the way, this suggestion of cloud cover isn't mine either. It's been mentioned by my professors and also in my environmental geology text, which said that NASA considers cloud cover the single biggest variable in the GW debate. So this isn't just my own blind speculation, it is the speculation of many others.

Anyway, this effect will not happen at all before the climate already has changed. Significantly increased cloud cover is in itself a climate change!

Of course, climate changes are inevitable regardless of whether or not there were people here.

It is a possible result of global warming, but global warming could also possibly cause icecaps to melt instead. We cannot know for sure. But of course, if glaciers grow enough to significantly increase albedo, it would be a sure sign of a major local climate change. If this happen as a result of human activities, it would truly be a human caused climate change!

The point with these scenarios is that global temperature may be at equilibrium. That's another thing we don't know.

Now you are exaggerating. Your graph indicates that changes in sun activity give temperature changes in a range up to about 1-2C or something.

The graph from Science shows a direct correlation between solar output and temperature increase, which leaves little room for anthropogenic CO2. However, that is from 1991. I am waiting for a reference that may discredit it.

Human contributions to the greenhouse effect are estimated to cause a little more change than that in the coming century.

Are estimated. You see, once again we come back to the fact that all global warming predictions are based on software models with minimal real-world data to constrain them. No matter how good your software is, you will not make up for missing data. No matter how many runs you do, you won't make up for bad starting assumptions.

Oh, and if carlos is right that this source was factually wrong, I don’t think we should take it too seriously.

And he may well be right. If he is, it's important.

 

[carlosMM]

gene, pikachu, I'll ask our big climate research boss about that paper (but he has not even time to write a 3 line letter of invitation this and next week )

 

[Gothmog]

Possibly. I'd like to look up the earlier papers that originally detailed the greenhouse effect. Maybe you can help by giving cites?

Gah, try any dynamic meteorology text book. This was worked out long ago by arrhenius (1920's?)

I suspect that after a certain point, further increases in CO2 concentration won't increase temperature. Where that is, I'd like to know, and I'm sure somebody has published it.

We are no where near that level. I already posted a bit about the current nature of saturation wrt various infrared bands. If you want to argue that point more I'm sure I can dig up a plot of the current state of affairs after lunch.

I remember reading that by the time saturation of the CO2 bands occurs there would be significant health effects due to carbonic acid forming in human fluids (lungs and eyes).


Pretty reasonable post, but this

Not necessarily, since it is an equilibrium process. The atmosphere can only contain so much water vapor before it condenses into cloud cover. Increased temperatures are more likely to increase cloud cover and precipitation than average humidities.

Is wrong as far as I know. The primary feedback is increasing average humidities, the secondary one is cloudcover.

You site NASA, here's a recent AP article about what the director of the NASA Goddard Institute for Space Studies, James E. Hansen, said about Shrub and science and global change.

http://www.space.com/news/bush_warming_041027.html

 

[Akka]

Politicians use global warming as a stalking horse to advance their agendas. If I scare my constituency with it, and then blame all the future problems on my opponents, I can win votes.

Government agencies use it to extend their own authority, thus serving the bureacrats in charge. If I am running a Federal agency, I will be competing with the rest of the government for funding. That means it would behoove me to keep searching for "problems" that need to have money thrown at them in order to justify the agency.

The media use it because any kind of a scare will boost ratings. When was the last time you got people to watch the news by saying that nothing was ever wrong? But if you threaten them with something, you will keep them watching.

Activists that advocate various forms of wealth distribution can use Global Warm as an excuse to penalize Western Nations and place further industrial advantage upon Third World nations, which are less affected by the Kyoto Treaty.

And scientists (who are, after all, the ones who discovered, explained, etc. about global warming ?).

I have another vision : the overwhelming majority of people who refuse global warming, are the ones who say on the other hand that Kyoto would destroy the economy and things like that.
The overwhelming majority of scientists have nothing to win with saying that there is global warming, and still they support it.

When you have scientists (who are the ones who should know about science, right ?) on one side, and people who have economic interests on the other... Guess who is more reliable ?

 

[gene90]

You showed a number of paleoclimatological plots, good. What do they mean to you?

They mean that Earth's climate has warmed, without industry, to the same degree as it has today. Where were the Roman SUVs?

Yes, they can be interpreted in various different ways. Have you really looked at the literature on the subject written by people who spend 80 hours a week trying to understand them?

This sounds like you're toying with an Argument from Authority fallacy.

But I intend to look up your references.

First of all, you have shown a plot of the 11 year sun spot cycle, which is not correlated significantly with solar output.

Uhhhhhh, no I haven't.

I am impressed by the civility shown in these threads so far.

But I will not tolerate your questioning of my understanding of the data, and then a clear demonstration of your ignorance of what I have actually posted.

This is what I posted.

It is not an 11-year solar cycle, but shows a secular increase of output since 1860.

Science is a top journal, and work published there is typically groundbreaking and not yet fully established.

All journal publications are like this.

Again, what makes you think that no-one but you is aware of such data?

Right. A personal attack.

Now you want someone to explain why global temperature does not match global CO2 concentrations across earths history. Sigh. Why not explain why you think they should?

It's a simple point.

If CO2 is a controling influence on temperature, then concentrations should correlate with temperature.

Various feedbacks operating at various timescales have already been discussed in this thread. Do I really need to say more about that?

Yes. You should explain how we understand all of these feedbacks well enough for the models to be accurate, and why, if CO2 concentration is not related to climate historically, why you believe that increasing CO2 concentration will cause an increase in temperature.

You provide a few more references that mostly outline the doubters point of view in the climate change topic. This is healthy, though none of these references are in top tier journals.

Argument from Authority fallacy.

No reputable scientist would make this claim.

Uh huh.

I appreciate your references but a lot of the above the was simply hand-waving ("no top-tier journals mentioned it") and comments like the above "no reputable scientist would make this claim".

Future authority arguments and attacks will result in the post being ignored.

 

[gene90]

the overwhelming majority of people who refuse global warming, are the ones who say on the other hand that Kyoto would destroy the economy and things like that.

But it is bad for the economy. To try to impose economic restrictions like Kyoto based on flimsy evidence is reckless and irresponsible.

When you have scientists (who are the ones who should know about science, right ?) on one side, and people who have economic interests on the other... Guess who is more reliable ?

Scientists are on both sides of the issue. Unfortunately, the media only represents one side.

 

[gene90]

We are no where near that level. I already posted a bit about the current nature of saturation wrt various infrared bands. If you want to argue that point more I'm sure I can dig up a plot of the current state of affairs after lunch.

I am satisfied with your assurance that it has been dealt with.




Pretty reasonable post, but this Is wrong as far as I know. The primary feedback is increasing average humidities, the secondary one is cloudcover.

You site NASA, here's a recent AP article about what the director of the NASA Goddard Institute for Space Studies, James E. Hansen, said about Shrub and science and global change.

So we're arguing over the personal political opinions of bureacrats? I liked the journal references better.

http://www.space.com/news/bush_warming_041027.html[/QUOTE]

 

[storealex]

My English sucks, and Im quite frankly lost in all the big words and... umm stuff... yeah, stuff is a nice word.

Gene, you're Danish right? At least one of your graphs are in Danish. Would you, provided you are Danish, be interested in discussing global warming in our own language, over mail or something? Because I disagree alot with you, but I don't have the time and skills to engage in such a discussion in anything else than my mother tounge.

 

[Gothmog]

The graph from Science shows a direct correlation between solar output and temperature increase, which leaves little room for anthropogenic CO2. However, that is from 1991. I am waiting for a reference that may discredit it.

Done and done, and see below.

But I will not tolerate your questioning of my understanding of the data, and then a clear demonstration of your ignorance of what I have actually posted.

This is what I posted.


It is not an 11-year solar cycle, but shows a secular increase of output since 1860.

You need to look again at what you posted.
Here is the article title "Length of the solar cycle: An indicator of solar activity closely associated with climate"

Here is the abstract

Reid (1987) suggested that the solar irradiance has varied in phase with the 80- to 90-year period represented by the envelope of the 11-year sunspot cycle and that this variation is causing a significant part of the changes in the global temperature. This interpretation has been criticized for statistical reasons and because there are not observations that indicate significant changes in the solar irradiance. A set of data that supports the suggestion of a direct influence of solar activity on global climate is the variation of the solar cycle length.

So yes they are using the 11 year sunspot cycle as an indicator of solar irradiance. Even your plot has the title 'periodlength' as its y-axis. That is the actual length of the '11 year' sunspot cycle.

I admit to toying with the argument from authority fallacy, this topic is very complex and I don’t have time to take you through what would be a four year course of study. Of course there is some agreement on this point, that you should at least listen to people who spend the time to study complex problems. At least Hume thought so.

Science is a journal where more speculative ideas end up. The articles are short and tend to be interdisciplinary. In general the ideas are then published in more detail in other journals, such as the ones I referenced. Nature is like that too. Not all publications in all journals are groundbreaking… are they?

Yes. You should explain how we understand all of these feedbacks well enough for the models to be accurate, and why, if CO2 concentration is not related to climate historically, why you believe that increasing CO2 concentration will cause an increase in temperature.

Models on time periods since the industrial revolution are pretty well established. Partially this is because we have good boundary conditions and understand various other climatic trends that were operating on this timescale (e.g. the haline circulation has not changed, etc.). Also many feedbacks, such as you list, have not had time to operate. Finally, I have made it clear in various posts that the topic is climate change, not an increase in temperature. Stratospheric temperatures have actually decreased for well understood reasons (i.e. CO2 is the main heat dispersal mechanism in the stratosphere).

Argument from Authority fallacy.

Actually in this case you were saying that there is no general consensus among scientists. This is not to say that there are no dissenters, but that consensus exists. In this context referencing the best read journals is not an argument from authority. Rather it is a description of how we can measure whether the consensus exists.

Please find me one reputable scientist who has published anything like this

A huge connection, as shown by the figure published in Science. So much that it seems to leave little room for anthropogenic influence, or much of anything else.

Since the early 90’s. It must be in a peer reviewed journal that has at least a middling ISI ranking.

Edit: to call James Hanson a bureaucrat is to show your ignorance. He is a very well respected scientist.

 

[gene90]

Gene, you're Danish right?

No. Sorry.

 

[gene90]

I admit to toying with the argument from authority fallacy, this topic is very complex and I don’t have time to take you through what would be a four year course of study.

Fair enough, though understand I'll continue to complain.

I recognize that you know considerably more about this than I do. Let me admit that immediately, and not let that be lingering issue. In fact, my opinion of global warming may be subject to reexamination as time goes along. I know professors that are very opposed to the idea, and professors that are very supportive of the theory.

Not all publications in all journals are groundbreaking… are they?

No, but they are, by definition, original. One paper in any journal usually is not sufficient to prove a point. All are subject to future criticism and review. As that graph clearly was.

Please find me one reputable scientist who has published anything like this Since the early 90’s. It must be in a peer reviewed journal that has at least a middling ISI ranking.

I'll look into it. But first, where do I find the ISI rankings? Also, what are your standards of bias? I don't want to cite AAPG Bulletin and have you poison the well about it being published by the American Association of Petroleum Geologists.

I don't believe in a consensus based upon my personal experiences. I can walk upstairs and find a few geologists who believe in global warming, and I can find a few climatology people that don't. One constantly pontificates on it class. They don't publish specifically on GW, but they are published scientists.

EDIT: What about the historical record of global warming that predates industry?

 

[Gothmog]

ISI is the Institute for Scientific Information, its impact factor is a measure of the frequency with which articles are cited in other journals. It is considered a measure of a journal's influence.

If you are at a decent school your library should have a collection of the ISI reference database, which will include the impact factor list.

Science and Nature are near the top, in part because they tend to publish important work in its relative infancy. The kind of work that obviously needs more study, but is too important to wait. Also, this sort of paper will spur lots of additional, more detailed, work thus helping to test the validity of important but poorly supported ideas quickly.

The consensus exists among the scientists who actually work in the field, not 100% obviously, but a consensus. This is measured by publications in journals with high impact factors.

Consensus does not imply truth, but the question was about consensus and it does exist.

I have opinions on sociology, and I am a working scientist, but I don't pretend to contribute to any consensus that sociologists may have in their field.

 

[Gothmog]

What about the historical record of global warming that predates industry?

It exists, its study is the field of paleoclimatology. It helps us understand climate feedbacks, and the potential dangers of messing with climatically important variables. It is very hard to model, due to lack of boundary conditions.

I'm not sure what your question really is, I've gone over a bit of discussion with BasketCase on these historical records.

 

[gene90]

What about the historical record of global warming that predates industry?

It exists, its study is the field of paleoclimatology. It helps us understand climate feedbacks, and the potential dangers of messing with climatically important variables. It is very hard to model, due to lack of boundary conditions.

I'm not sure what your question really is, I've gone over a bit of discussion with BasketCase on these historical records.

I was unable to find the ISI reference on the first try.

Yes, I know what paleoclimatology is. See the charts above.

My problem is that Earth's climate warms and cools naturally on the same order of magnitude as the alleged anthropogenic global warming. A 150 year warm excusion is meaningless to me.

 

[gene90]

Let me elaborate.

This is what temperatures have been doing:

Global temperatures have been warmer than they are today numerous times in the past, without assistance from the burning of fossil fuels. Now, there is a short-term increase in global temperature, and we suddenly need anthropogenic CO2 to explain it? And we need multinational treaties to control it? It looks to me like the Earth's climate is simply doing what it has been doing for the last couple billion years and we just recently discovered it...and immediately assumed it was our doing.

Several aspects of the global warming theories are troubling. For one, every unusual weather event seems to get blamed on it. Nothing weather-related is ever considered a fluke anymore. Too warm one winter? Global warming! Too cold one winter? Global warming! Weather is variable, but people don't understand that. This is part of where the media bias comes in. Snowstorm Uncommon, but Normal Event in Our Climate doesn't sell papers like Freak Snowstorm Caused by Global Warming?. People like the latter because (1) it gives a greater meaning to a random event (2) people are bored with ho-hum news and need excitement and (3) it gives them someone to blame (evil corporations) for their bad weather. Nevermind that it is their money that keeps the evil corporations running. And then you have the political parasites, like the banner I saw in Florida recently: Global Warming Causes More Hurricanes, but Bush Doesn't Get It. Who was it who said that nobody has anything to gain from advancing the anthropogenic global warming theory? But I digress.

It is my opinion that anthropogenic global warming is a non-falsifiable construct. It all runs on models and isn't constrained by real-world data, except historical temperature charts--which don't necessarily mean anything. If I were to set out a thermometer one August morning, and recorded a climb in temperature of seven degrees over seven hours, that would be a serious warming. If I were ignorant of how temperature changes worked over longer timespans, I might take that 7 degree rise and predict my death from thermal shock in the next 48 hours. This is exactly what we are doing with climate records.

 

[Gothmog]

This is the same argument as BasketCase was making, but it doesn't get at any of the important issues of the current theory of climate change. Nor does it explain how well century scale models do in capturing recent climate change. The energy balance on this timescale is well understood.

Basically your saying that since the earth's climate has been variable on a 10000 year timescale in the past, humans can't influence climate? That simply doesn't make sense to me. There is no there there, neither deductive nor inductive reasoning.

Climate has varied in the past and will in the future regardless of human activities, agreed. Now how do you get from there to saying that human activities are not affecting climate? or discounting the best current understanding of how climate works?

Humans live on a generational timescale, depends on how you define it but maybe 30-60 years. So how can a 150 year warm excursion be meaningless to you?

Are you saying that you think that is the only evidence for anthropogenic climate change?

Here is how I framed my question to Basketcase, which he declined to answer.

Are you disputing that humans have significantly changed the energy balance of the earth system? That we have changed the aerosol loading and distribution? What?

No, we cannot exactly predict what will happen.

Yes, we can say that humans have influenced climate in the last 200-300 years with a very high level of confidence.

It may be that various feedbacks will work together to mitigate human influences (known as the Gaia hypothesis), but it seems a slim hope. Certainly paleoclimatological records would suggest the opposite. We've been living in a privileged time wrt climate, stable for 10000 years. We should do our best not to kick the system too hard until we understand it better.

It is certainly possible that greenhouse gasses will help us avoid future ice ages, but that sort of global engeneering should only be done with a consensus about its efficacy.

Edit: just saw that last post.

First your plot doesn't include the last couple decades of temperature increases. Second, you need to stop confusing what you hear on the evening news with what scientific consensus is.

 

[gene90]

This is the same argument as BasketCase was making, but it doesn't get at any of the important issues of the current theory of climate change. Nor does it explain how well century scale models do in capturing recent climate change.

See, this is one of my points of contention. You're always trumping models. Where is the real data?

The energy balance on this timescale is well understood.

Oh? How much is the urban heat island effect increasing global temperatures? How much is global thermal pollution? And how did you measure it?

Basically your saying that since the earth's climate has been variable on a 10000 year timescale in the past, humans can't influence climate?

No. I did not say that humans cannot influence climate. The point is, that when placed in historical context, there is nothing particularly interesting about the current rise in temperature. Greater increases have occured without obvious human intervention in the past, quite regularly. Immediately before "global warming" allegedly really took off, we were in an abnormally cold period called the Little Ice Age. Also, looking at the historical record, climate is not static, it is constantly changing, either going up or going down, with many rises being steeper than the one today. Big Surprise: climate change is happening today, at a somewhat mediocre pace. It just happens to be warming. It could just as easily have been cooling. And if it were cooling, you'd still probably blame it on industry, only with different gases.

Now how do you get from there to saying that human activities are not affecting climate?

There is no evidence of anthropogenic global warming. Only models. And those models are no better than the assumptions and data you start with. You've already admitted that there are numerous feedback loops we don't understand. If we don't understand it, why do you expect your results to even bear a remote resemblance to reality?

Humans live on a generational timescale, depends on how you define it but maybe 30-60 years.

Which is nothing compared to the centuries of time along which climate change occurs.

That's exactly one of the points I am making, you have a very short term measurement of temperature and you are trying to extrapolate that outside of the historical context. It's like an analogy a prof made (who happened to believe in global warming). Every fall there's a change in average temperature. To an oak tree, it's routine. To a daisy, it's catastrophic. 150 years is a short interval that must be placed in the proper context. It is little considered even to the length of human civilization, much less the entire paleoclimatic record. We have data that seem to indicate a recent increase in temperature. What that means depends on the context. Turns out the Romans had a bigger issue with global warming than we do today! Why then, am I supposed to be worried about it?

So how can a 150 year warm excursion be meaningless to you?

Because if I pick a different interval to plot temperatures over, I can make the climate look like it is doing anything I want it to. You guys "just happen" to be enamored with 150 years.

Are you saying that you think that is the only evidence for anthropogenic climate change?

It's the one that proponents constantly march about. But I bet you have other "evidence" too, that probably is also out of historical context.

It may be that various feedbacks will work together to mitigate human influences (known as the Gaia hypothesis)

Bah. Gaia is restricted to the biosphere, and it's highly speculative. I've been concentrating on inorganic systems and feedbacks.

Certainly paleoclimatological records would suggest the opposite. We've been living in a privileged time wrt climate, stable for 10000 years

The Viking colonists of Greenland and Iceland would beg to differ. Would you like to comment on the Little Ice Age? The Medieval Climate Optimum?

Besides, the above is a loaded definition. How do you define "stable"?

Climate is always in flux, and always will be, regardless of human actions. Barring mitigating advances in technology, our cities will inevitably be drowned. And our cities will be inevitably ground into dust by glaciers. (In which order, I don't know.) The were be famines, and there will be forced migrations. This is not the fault of industry, it is the consequence of living on a dynamic Earth.

We should do our best not to kick the system too hard until we understand it better.

This is a valid point. I don't disagree with you here, at least as far as we shouldn't dump billions of tons of CO2 into the atmosphere for the heck of it. But there is a reason we do the things we do, isn't there? It drives our quality of life.

We should also recognize that human beings, as living things, alter our environment, by definition. The only way to avoid "kicking the system" in some way is to evacuate the planet. No matter how much coal we burn, we will never have the effect on this planet that the development of photosynthesis had. For obligate anaerobes, it was an apocalypse. But we don't call the "natural" levels of molecular oxygen "pollution", do we? Because we apply different standards to human influence when they have the same practical result: that of changing the global environment.

Now, somewhere there is a line we can draw between having a decent quality of life and having and excessive (destructive) influence on ourselves and environment. For me to draw that line against an otherwise innocuous gas like CO2, whose production is so vital to civilization, I need really powerful evidence. I just don't see it.

It is certainly possible that greenhouse gasses will help us avoid future ice ages, but that sort of global engeneering should only be done with a consensus about its efficacy.

I agree with you on this issue. I don't advocate CO2 production as an attempt to avoid an ice age. I simply see it as important for economic reasons. Screwing with the environment as a result of our established economic routine is one thing, but screwing with it for the sake of screwing with it is another.

First your plot doesn't include the last couple decades of temperature increases.

So you're favoring temperature rise over 20 years instead of 150? When I find 150 too short?

This is the infamous Mauna Loa CO2 concentration curve. We've all seen, it's plastered across most every relevant textbook in some form:

If something critical to the anthropogenic theory happened since 1985, where are the increases in the slope of the CO2 concentration on the curve?

Second, you need to stop confusing what you hear on the evening news with what scientific consensus is.

I am frustrated in general with the media, please excuse me.

 

[Gothmog]

See, this is one of my points of contention. You're always trumping models. Where is the real data?

What real data do you mean? When you set up a model you incorporate things like topography, solar irradiation, changes in trace gas composition, ocean circulation, initial climatic conditions, etc. This is all from data, then you incorporate physical laws, such as diffusion, convection, absorbtion, reflection. Then you run the model, the biggest uncertainty is cloud formation (at the century timescale) but there are some constraints on clouds from data too and one can run a suite consisting of different assumptions.

To summarize, the data are typically called ‘boundary conditions’ and certainly huge heaps of it are necessary for any decent climate model.

Sometimes, for a specific study, you might allow a variable that is typically constrained by data to vary. For example including a physical model of oceanic circulation to try and understand why thermohaline circulation might shut down (which would be a disaster), or a physical model of ecology to try and get at how a forest might turn into a grassland in the future climate.

Oh? How much is the urban heat island effect increasing global temperatures? How much is global thermal pollution? And how did you measure it?

The urban heat island effect is not significant globally as far as I know. What do you mean by thermal pollution? Much data is now measured by satellites, incoming solar radiation, outgoing infrared, cloud cover, cloud properties, etc. Trace gas composition is measured by various groups, data archives exist on the web. Ecological changes are either from historical or paleoclimatological records. etc. etc.

No. I did not say that humans cannot influence climate. The point is, that when placed in historical context, there is nothing particularly interesting about the current rise in temperature.

You are fixated on the current rise in temperature, to me that is a small issue. Scientists don’t expect the heat to all just show up in the system as surface temperature. There is a lot of thermal inertia in the system, then the feedbacks. The ocean is absorbing a lot of the CO2 we emit, and a lot of the additional heat produced. What will its response be? I don’t know.

You have not understood what current models can do, you are focused on what they cannot. Why not examine the science involved? For example, sulfate has decreased in the last decade (due to regulations), sulfate aerosol is highly reflecting and thus a cooling influence. This is a necessary component of climate models.

What part of the science do you disagree with?

Greater increases have occured without obvious human intervention in the past, quite regularly. Immediately before "global warming" allegedly really took off, we were in an abnormally cold period called the Little Ice Age.

It wasn’t that cold, thus the ‘little’ ice age. As I have said climate has been unprecedentedly stable, and unusually warm, for the last 10000 years. Don’t expect that to continue.

There is no evidence of anthropogenic global warming. Only models. And those models are no better than the assumptions and data you start with. You've already admitted that there are numerous feedback loops we don't understand. If we don't understand it, why do you expect your results to even bear a remote resemblance to reality?

Well, we understand the timescale of the feedbacks pretty well. When we try to model timescales for which there is data (i.e. good initial and boundary conditions), and where the most complicated feedbacks do not opperate, we do a good job.

I have said explicitly that we do not know what to expect the climatic response to be, just that there will be one. Humans have significantly affected climate forcing, and not just with greenhouse gasses.

Also, I am not blaming anything on industry. I enjoy our current standard of living, and I want my children to enjoy an equivalent one. That is why you should be concerned. We are significantly changing variables that force our climate. We have enjoyed a period of unprecedented climate stability in the last 10000 years, during which time human society came into being.

You were the one who posted the plots from 100000 and 420000 years ago, what do they tell you about stable climates conducive to human development and the last 10000 years?

Bah. Gaia is restricted to the biosphere, and it's highly speculative. I've been concentrating on inorganic systems and feedbacks.

Gaia is typically used in a wider context, though you are correct about its historical roots.

You are basically arguing that even though humans are significantly affecting climatic variables you don’t think that humans are affecting climate. That is Gaia in a nutshell, the belief that the earth will take care of its self, and us.

Unless I misunderstand your silence to my questions and you are indeed arguing that humans have not significantly changed the energy balance of the earth system, nor the global aerosol loading and distribution.

Because if I pick a different interval to plot temperatures over, I can make the climate look like it is doing anything I want it to. You guys "just happen" to be enamored with 150 years.

I am not enamored with 150 years, I don’t even really care. I am not sure who ‘you guys’ are.

The science behind climate change is much more than current rises in surface temperature. It is about understanding what variables force climate, and how the system responds to various forcings. I am interested in timescales where we have specific data about variables that affect climate, some of which are influenced by man. Another interesting timescale has to do with the agricultural revolution and the large scale conversion of ecosystems to monoculture.

So you're favoring temperature rise over 20 years instead of 150? When I find 150 too short?

No, just that if you include the last 20 years you will find us up nearer to Rome.

If something critical to the anthropogenic theory happened since 1985, where are the increases in the slope of the CO2 concentration on the curve?

What are you on about here? As I mentioned sulfate aerosol is a necessary component to understanding climate over the last couple centuries, as is soot, and even volcanoes. Pintatubo was a great natural experiment that verified how sulfate aerosol affects climate, and that the water feedback is positive. To really model paleoclimates you need to know historical volcanoes over that time period, and any major meteor impacts as well. Long timescale models do include them in a stochastic sense.

I am saying that your kneejerk reaction against the environmental movement is blinding you to the scientific realities about the anthropogenic influence on the earth system.

You had your plot of the solar connection, you seemed to stake a lot on that. It turned out to be wrong. Couldn’t it be that humans are influencing the climate?

Now, somewhere there is a line we can draw between having a decent quality of life and having and excessive (destructive) influence on ourselves and environment. For me to draw that line against an otherwise innocuous gas like CO2, whose production is so vital to civilization, I need really powerful evidence. I just don't see it.

I agree with this, and as I said elsewhere in this thread I fully expect humans to burn every bit of oil we can find – and then start on the coal again. All Kyoto will do is slow that process a bit.

I am just arguing that we should take responsibility and try to understand the consequences of our actions as best we can. We are affecting climate, the science is quite clear.

It is irresponsible, IMO, to assume that feedbacks will somehow save the day and not allow climate to do other than what it would have done anyway.

I also happen to be interested in the necessity for humans to someday control climate in a systematic way. I don’t see it as desirable for us to enter another ice age.

 

[gene90]

I am just arguing that we should take responsibility and try to understand the consequences of our actions as best we can. We are affecting climate, the science is quite clear.

I disagree with you on the science, but admit that it isn't cut-and-dry.

I found an interesting reference this afternoon:

Gerhard, Lee. Climate Change: Conflict of Observational Science, Theory, and Politics. AAPG Bulletin. Volume 88. Number 9. September, 2004. pp. 1121-1220.

In the above, the case is explicitly made for current warming to be due to solar forcing. See figure 3 on page 1216.

I agree that we should spend money on research in anthropogenic climate change. In fact, on issues of research, I'm bullish on most everything.

It is irresponsible, IMO, to assume that feedbacks will somehow save the day and not allow climate to do other than what it would have done anyway.

And I feel that it is irresponsible to damage the economy with restrictions based upon the concept that humans may or may not be influencing climate change, especially when those changes are probably going to happen anyway.

 

[MattII]

Eart is in an ice era at this very moment. It has been calculated that 10 percent of the world is permanently covered in ice or snow, and a further 14 percent is in a state of permafrost. Before 50 million years ago there was no permanent ice on earth, and during the late cretaceous period Tyrannosaurus Rex often lived within 10 degrees latitude of the north pole, and there were dinosaurs in Australia, then more southern than today that also survived many winters.