Global Cooling?

I don't understand your point. Was there ever a source of CO2 being pumped into the atmosphere in the past like there is now? If not then there is no direct way to have global scale evidence one way or another. Unless you have a time machine handy, you are making an impossible demand.We do know from physics/chemistry that CO2 is one of the gasses that reflects the IR light the earth radiates to cool itself. I'm no expert, but obviously this is expected to cool the earth and most computer simulations agree that this effect explains most of the warming we have seen.

Sunspots do tend to be correlated to the sun’s energy output which could directly change the earth's temperature, but there is another way they could have an effect. Sunspots happen more when the sun's magnetic field is strong and this magnetic field tends to drive away the electrically charged cosmic rays that bombard our atmosphere. These cosmic rays produce ions in our atmosphere that could in theory precipitate cloud formation, which could have a net cooling effect depending on the cloud's height and density. This is a favorite argument of some global warming skeptics: the sunspots drive away cosmic rays which reduce cloud formation. There are just two problems with this.a) I don't think there is any evidence of cosmic rays increasing cloud density. They form clouds in cloud chambers because before the cosmic rays pass through there is nothing for condensation to stick to. The atmosphere, on the other hand, has plenty of dust in it already that clouds can form around. Cosmic rays may not help.b) We can measure both the rate of sunspots and of cosmic rays. Both follow the solar cycles as one would expect, but there is no trend consistent with our observed warming over the last 30 years. Here is a crappy plot showing this from the University of Chicago Climax neutron monitor. It shows the rate of incidence of neutrons produced from cosmic rays overlaid with sunspot #s:Based on this evidence, I see no reason to link sunspots or cosmic rays in any way to the warming that has been observed recently. Maybe they are indicative of future sun behavior that could be relevant. But you're better off looking at the actual flux of solar energy reaching us on the earth if you're trying to understand how the sun could have influenced the current climate.

True, the sun has a slightly higher activity now than it did 150 years ago. Razd has already given you some solar data, but here is one showing a larger time scale from wikipedia. Based on this plot, showing solar energy output during the recent period of warming, I don't see any reason to think the sun is the cause. Do you?Edited by fgarb, : Shrinking the image

I think that's generally accepted, though it depends on the nature of the clouds. Clouds block both incoming sunlight and outgoing infrared radiation, so they can have both a warming and a cooling effect as I understand it. I may be wrong, but I think thicker clouds will have less of a cooling effect than thinner ones since thinner ones would block most of the IR while letting through most of the direct sunlight.At any rate, cooling from clouds is taken into account by most modern simulations that are run which still find an expected warming trend. Maybe you disagree with most of the scientists who study this and don't believe the simulations. Fine, but we know that the cooling from clouds is a lesser effect than the warming from greenhouse gasses. We know this because if it weren't the earth would be much colder than it is today (I believe our oceans would be frozen without the greenhouse effect of water vapor but others can check me on this). And we know it because greenhouse gasses make Venus warmer than Mercury despite the fact that Venus is much farther away from the sun.As for your study, I'll have a look tomorrow when it's not so late, but I am initially skeptical simply because they a) claim with such certainty that the conclusions of mainstream climate studies are wrong, and b) They make very precise claims such as that 5.53% of the warming is due to humans to describe a process that has such large uncertainties. No statistician worth their salt would use so many digits unless they quoted the relevant uncertainty to go with it.

Thanks for the welcome and for the advice on formatting! I'll apply your suggestion next time around. I know nothing about carbon-14, but I don't see what else could possibly change the nuclear structure of atoms in mass quantities in the atmosphere, so that stands to reason. To be completely correct, the blue plot shows neutrons that are produced by the cosmic rays, not the rays themselves, but it amounts to the same thing. That's what I'm trying to get at. If the sun is to blame we should either see more energy reaching the earth from the sun over the last few decades, or we should see more solar flares and thus fewer cloud-forming cosmic rays coming in over the last few decades. We see neither according to the data I've seen and posted. I'm no expert in this field - just an interested layperson - but I can't think of any other way the sun could be swamping the greenhouse effect.

Historically sun cycles dominated. But during the time of the recent warming there are a) humans pumping greenhouse gasses into the atmosphere and b) no significant change in solar power output or solar flares ... at least not according to the data I've seen and posted. What could possibly be making you say that b is the cause of the warming? Maybe it's something in this funny link you posted. I'll have a look at it tomorrow when I'm less sleepy.

I have spent too much time fact checking your first link to go on to the others at this point, so let's focus on it. The key claim of this site is that water vapor makes up 95% of the greenhouse gas effect. Let's look at the DOE source he cited to support this crazy claim: There is more to the atmosphere than just the troposphere! If you want to look at the numbers for the entire atmosphere, his own source tells you them in the table just below. According to his own source, if you removed all CO2 from the atmosphere it would trap ~12% less heat, and if you removed all H20 from the atmosphere it would trap ~36% less heat. And of course these numbers are from 1978 when there was less CO2 in the atmosphere than today. So to claim that water vapor makes up 95% of the greenhouse effect is crazy. This guy should learn not to cite his sources if he's going to quotemine them.So that's his first major "mistake". The second is implying that humans are not the cause of most of the CO2 increase since before the industrial revolution. That's ridiculous. What could possibly be pumping more CO2 into the atmosphere than we are (see the image below)? Maybe he's ignoring domesticated animals and deforestation? And even if you could think of a natural cause, what are the chances that nature waited hundreds of thousands of years and then did so just as we were starting to industrialize? It makes no sense. He gives no justification for this claim, and the reference on his table does not work.Those two mistakes have a huge effect on his result. Let me try a simple correction. Using his source, CO2 makes up 12% of the greenhouse effect. From this plot of CO2 concentrations the industrial revolution increased CO2 concentrations from ~275 ppm to ~375 ppm today, about a 35% rise. So I would very roughly estimate that CO2 resulting from human industrialization accounts for around 35% of 12%, or about 4% of the total greenhouse effect ... not the 0.28% he arrives at. Given that with no greenhouse effect at all our planet would be a block of ice, that sounds like a fairly significant increase to me.Feel free to defend these claims, but they sure look completely wrong to me. And is there a reason I should trust the other sites you posted? Correcting these mistakes takes time.

Ok ... I am going to take a deep breath and try not to get angry. This entire disagreement is because New Scientist is a stupid hack of a science magazine (sorry, I am bitter over past distortions they've made). The complaints raised against Lockwood and Frolish are entirely without merit, as anyone would see if they actually looked at the paper instead of just basing everything off of that deceptive plot New Scientist posted. The minima is not more important than the maxima. All the data points are equally important. The figure New Scientist used is after drastic smoothing (a practice I generally don't like) has been performed, and they removed all reference to the smoothing. This smoothing diminishes both local minima and local maxima without altering long range trends. Minima and maxima have nothing to do with the long range trends, which are still preserved and are what the paper was focusing on. There was no attempt to hide anything. The unsmoothed data is presented in the very first figure in the paper if you want to see it. They were not derived by a formula. They are taken directly from data and are presented in Figure 1 of the paper. The fact that your site focuses on the New Scientist figure instead of what the researchers presented shows that they are either morons or liars. Based on the content of the site, my conclusions is: liars. What does Lean have to do with this? Your website posts her data and then completely distorts it. Let's look at a couple of the jewels among mistakes: They can't honestly address Lockwood's arguments, so they slander him as being a pusher of pseudoscience instead. Because unlike the biologist making this accusation, Lockwood did publish instead of releasing to the media. That's what the paper is about: read the abstract! Based on what he says in the rest of the article, this biologist would be laughed at if he presented his arguments to other scientists. Yeah, you can get horribly wrong answers like this when you fit a line to a distribution that is not even close to linear. Also shown on the plot is a polynomial fit which is more accurate but still very wrong. And guess what, this polynomial fit does show that the solar irradiance has decreased since 1985. Both of his fits are completely wrong ... just thought I should point out that one of them contradicts his own thesis.You know what, I'm not even going to go into the rest of the site. That's enough for one post. Maybe what I've said is hard to understand. If so I apologize, but I'd be glad to explain why your website is completely wrong in more detail using less mathematical language if you want. As Percy said, don't trust "scientific" arguments that haven't been published when they claim to refute arguments that have been published. Especially when it comes to politically charged topics like global warming.

I'm confused about what you're trying to say here. Yes, H2O absorbs slightly less radiation when other greenhouse gases are present becuase the other gases are abosrbing some of that radiation instead. If you magically removing the other gases, the amount of heat absorbed by the H20 will increase because it's the only gas doing any absorption, but the amount escaping into space will increase overall. I really don't understand what you're thinking. Can you explain? It really does not support global dimming.

Yes, adding absorbers does not increase absorption linearly. But there is no way that adding more absorbers can make the absorption go down. How much absorption goes up as a result of the presence of CO2 is the question which was answered by the DOE report that your website quotemined: about 12%. I have explained in detail the problems with your sites. If you disagree with or don't understand any of the errors I have found, please say so. Otherwise, I'm not going to waste my time revisiting them. Perhaps it would be better to stop arguing about researchers and get back to the data.Solar activity: using data from your own website (I believe the data, not how it was analyzed), long term, average solar irradiance increased by about 1.4 W/m^2, or about one tenth of one percent between 1900 and 1960. Check me on this! That's a tiny increase, but it could account for a large portion of the warming in the first part of the century. I'm not arguing that. What I am arguing is that solar activity has not increased in the last few decades, while the temperatures have continued to go up. Let's look again at the most recent data, measured by satelittes. Ignoring the 11 year cycles, irradiance, flares, and sunspots are all flat. If someone uses a mathematical technique to show an increase, the technique is wrong. Use you eyes!If you don't believe this data, you can see the same thing from your own website, you just have to look at the last thirty-forty years of the data.Now let's look at temperature during that time period:Regardless of whether you take measurements from the ground, or with satelittes, global temperatures have gone up by ~0.4 degrees C during that same time period. To repeat, solar actvity has not gone up during the last thirty years, Lockwood and Frohlich even argued that it has gone down very slightly, but the temperature has gone up.

You bring up many interesting topics in this one post, each of which could lead to a lengthy conversation. From my perspective, it would be much easier to understand what you are saying and respond intelligently if we focus in more detail on a smaller number of topics. For now, why don't I address the topics that most directly connect back to what we've already been talking about. What do you mean? Are you talking about the idea of methane being released in large quantities from the ocean and permafrost due to warming? If so I'm pretty sure that hasn't happened yet in detectable quantities, but it is possible disaster scenario. Again, it isn't clear to me what you're saying. Is this close to your argument?: "The solar power output went up 0.1% in the first half of the 1900s. That led to warming which melted ice which made the earth darker so that it absorbs more heat. After the sun's power output leveled off in the 60's, the earth's temperature continued to rise simply because of its greater heat absorption, which led to more melting, more heat absorption, etc. Thus, there is no need for a greenhouse effect from CO2." Looking at the data from your own source, it looks to me like the sun's power output has been level since about 1960. I really can't follow your argument in the rest of this paragraph. Don't be too concerned about the results of any one year. Yearly anomalies happen all the time. It's the multi-decade trends that are relevant. You're thinking in a lot of directions at once I see. Up until now you've been convinced that we're heating up because the sun is getting hotter. Now you're worried that it's actually getting colder. But really, what we've seen in the last several decades is a flat solar output and an increasing temperature. Lockwood's analysis suggests a *very slight* decline in solar output, but there's no way this is strong enough to have had much of an effect yet. Possibly it can be indicative of a drastic drop in the future that will cause dimming problems, but what is the evidence that that's likely to happen? Man, you really don't like Lockwood. Does he owe you money or something?

John, for a while I hoped that we might have an honest discussion about the science of climate change, but it is starting to really look as though you have decided that humans can't possibly have anything to do with climate change, and you are casting about with blinders on, searching for *anything* that could possibly prove you right and trying to ignore evidence to the contrary. You link site after site and never pause to understand what they say. Then we go through and carefully explain to you why those sites are completely wrong, and you proceed to say "oh, well then human caused climate change isn't wrong for that reason ... it must be wrong for this reason ...". You throw out more sites that you don't understand and the process repeats. If your goal is to honestly debate the facts then I will work with you to understand them, but this is getting tiring.I suppose I will continue to call you on the falsehoods that you're spreading. This for example: I would find this more convincing if it weren't false in just about every respect. Where do you come up with this stuff? Let's look at what the National Academy of Sciences actually says: You know what other scientific organizations have stated that humans are probably the primary cause of climate change? The Joint Science Academies of the G8 Nations, the US National Research Council, The American Geophysical Union, The American Institute of Physics, The American Physical Society, The American Chemical Society, and many others. The list is much more extensive and I'm not going to write them all out.Can you name a single science organization that still officially states global warming is probably a natural phenomenon as you allege?

How about you defend or withdraw your claim that most serious climate scientists think the warming is natural, and then we can change the subject? You claimed the National Academy of Sciences supports this. I demonstrated it does not. So I will ask again, can you show me even one prominent science organization that agrees with these climate scientists you speak of? I see physicists, engineers, biologists, chemists, geologists, and social scientists on that list. There must be hundreds of thousands of scientists who meet the necessary qualifications to sign ... tens of thousands at least. Why do you think we only see a small fraction of one percent signing?

You are making a habit of claiming scientific consesuses that never existed. As Percy has said, there was never a scientific consensus about global cooling. Don't believe me? It's easy to prove me wrong. Just find a single science organization that predicted long term global cooling. Hell, I'll make it easier for you. Find me one single scientific paper (written by a scientist, not a novelist or a journalist, and published in a science journal) since 1970 that predicted long term global cooling or that we were entering an Ice Age. It should be a trivial task if what you say is true.

Percy has already responded to this, but I just want to add to it. A flip-flop would be to claim that the globe was not warming or that humans were not the cause, and then later change to the current scientific consensus. The National Academy did not do this. In 1975, they said they did not know. This makes sense. Back then things were a lot less certain. The science was more poorly understood (feedback loops from clouds, and cooling effects from sulphates), it was harder to disentangle solar effects from atmospheric causes because solar output had not demonstrably leveled off, and they did not have the computing power to grind through all the simulations that are used as supporting evidence today.So to summarize. In the 1970s there was no clear scientific consensus about whether humans were causing global warming. There was also no consensus that we were headed for and ice age. There was insufficient evidence to come to either conclusion. Today the evidence is much stronger, and most legitimate science organizations have stated that the earth is warming and humans are the primary cause.