Seriously, I wish people would stop getting so shocked about this.
Climatologists are not unaware that the climate has changed in the past. The issue is that climate is currently changing faster than it would have without human input, and that larger and faster changes are likely if we continue to increase our input to the climate system.
Preferring OS X is relevant because if you want to buy a laptop with OS X, you're now stuck with a glossy screen.
You can't buy and connect any screen you want without serious modifications to the laptop. Adding an external display is not the point; it's a portable computer.
Despite the summary, authors aren't literally like sellers at an auction. They don't receive any money for their papers. For journals with page charges they have to pay to publish!
Publishers are only "bidders" in the sense that they are competing to have the best papers published in their journals. But they don't compete monetarily — as I said, they don't pay authors. They compete through prestige: authors (often) want their papers to be published in the most famous, widely read, influential journal. Prestige is determined by selective choice in what the journals choose to publish, which scientific niche they occupy, etc.
The point is that the "stronger solar output" doesn't mean "strong enough, or with the correct time series behavior, to explain the warming we've seen", for reasons I have already exhaustively discussed.
You can cling to your claims only as long as you choose not to actually plug any numbers in and see what that kind of forcing predicts for the climate.
Who claims that solar output has had a dominant effect on the climate until 8-9 years ago?
Regarding the period of time over which solar hasn't been a dominant forcing, the IPCC says "between 1950 to 2005". Stott et al. say "the second half of the twentieth century". Foukal et al. say 30 years, although it should be noted that they're explicitly looking at satellite data which we only have for 30 years, and so can't give a number larger than that using that data. I suppose I can go dig for more explicit statements, but this is sufficient to indicate that I'm not the only one claiming that.
Currently neither of them can explain what we're seeing.
CO2 can easily explain the warming trend we've seen. If you're referring to the usual "we're experiencing global cooling" cliche, there isn't any evidence that the underlying long term trend has even changed beyond what can be expected from ordinary interannual natural variability.
even the wikipedia article on Svensmark's hypothesis has more info on the various claims and counter claims than you seem to display here
None of them get around the basic fact that you can't simultaneously match early 20th century and late 20th century temperature trends by appealing primarily to a feedback-amplified solar output, for the basic reason that the response doesn't look like the forcing. The result of the statistical analyses like the Tomassini et al. I mentioned boils down to the observation that if you amplify solar output enough to account for the late 20th century warming, you (a) get too much early 20th century warming and (b) the late warming still doesn't really match up in rate or magnitude when you take into account the ocean lag time (and its uncertainty). The only way you're going to do it is by postulating very different effects of cosmic rays on clouds at different time periods, which is not something that Svensmark himself has proposed.
Weird statement to make, since I just corrected you on that subject.
No, you didn't correct me. Solar trends have been basically flat for decades (which you still refuse to admit) — anything on the order of a few tenths of a W/m^2 is "flat" as far as the solar cycle or previous trends are concerned — and the solar cycles 22/23 are not high compared to any solar activity that has occurred in the last half century. You simply aren't going to explain a sharp increase in temperatures with solar output that hasn't increased.
(You make a serious scientific error when claiming "disproven" btw.
I meant exactly what I said.
No, the hypothesis is not falsified.
It has been, unless you postulate a weird nonlinear feedback constructed to have just the characteristics necessary to mask the fact that the cosmic ray feedback doesn't agree with the data. There is no physical mechanism which supports such a feedback, the supporters of the cosmic ray cloud connection themselves don't propose any such mechanism, and it's the last ad-hoc refuge of a failed theory.
There isn't enough data, but the data that exists is both in support as well as not.
There is enough data, and it clearly disagrees with solar output having a dominant effect on climate over the last 50 years.
... and thus we're back to having two competing hypotheses, both relying on unknown feedback mechanisms and neither having been tested enough.
Uh, no. We're talking about two competing hypotheses, one of which (solar) makes predictions which are wrong by an order of magnitude. The feedback mechanisms are not unknown — water vapor, lapse rate, ice albedo, cloud feedbacks, etc. have all long been studied. If you don't believe the individual feedbacks account for the majority of the total, the strength of the total feedback can be estimated from the data. If you try to apply different feedbacks to solar vs. everything else, no choice of amplifying solar feedback reproduces the data.
Now, please answer the question: If Hansen was your boss, would you publish an AGW-sceptic paper?
Yes, if I thought it was right. Now, since you claim to be such a big fan of science over politics, why don't you describe what's wrong with the science instead of resorting to vague allegations of bias.
(I've read most of the papers you've cited,
The hell you have. You don't even know what the solar trend looks like.
and also Svensmark's rebuttals of course.
Oh, fine, tell me what Svensmark's rebuttal is to Tomassini's estimate of the solar amplification factor. (Clue: he doesn't have one.)
It's still a hypothesis with a better match,
Except for the fact that it completely fails to match the surface temperature and ocean heat data, with any feedback factor you care to choose. And if you throw out the surface temperature data, your claim is even more nonsensical since you can't compare solar data to it either.
and more Occam'ish,
"The Sun affects cosmic rays which affect clouds which affect reflect sunlight" is not "more Occam'ish" than "CO2 absorbs longwave radiation", especially considering how few links in the former chain are directly supported by evidence.
than the IPCC CO2 wildly spiralling feedback nonsense)
Solar-cosmic ray-cloud warming involves all the same feedbacks that CO2 warming does, plus one extra feedback. When the feedbacks apply to CO2 warming, they're "nonsense", but when they apply to solar warming,
P.S. The IPCC didn't invent the CO2 greenhouse effect or climate feedbacks.
I'm sorry, but posting your own (faulty) speculation is a bad argument.
P.S. This isn't my "speculation", this is published research. If you bothered to read anything other than Svensmark, you would know this. Why you continue to cling to your disproven claims, I don't know.
(There is a 4 as well, of course, and that is that anything that's verified against surface temperatures is in doubt)
Well that would include your theory too, then. But that aside, the surface temperature record is not untrustworthy, for reasons I explained two days ago, and which you continue to ignore.
The only way you can persist with your claims is by waiting long enough, so that you hope everyone forgets your claims were disproven. It's getting to be really pathetic.
They're not flat, but they are very, very small — certainly far smaller than the trends in the preceding 50-100 years. As I've said, it's only changed by a few tenths of a watt per square meter. You can find the trends in some of the papers I've mentioned. I Googled around for a web version and found this. I don't know which reconstruction it is (it looks like Lean to me), but they all show this flattening.
2) I disagree with "it" having been tested
You disagree because you refuse to read the papers which test "it", including but not limited to the ones I've cited.
3) We don't know enough about ocean currents to claim that time lag cannot explain what we're seeing
Yes, we do. The paper I mentioned explicitly calibrated the time lag to the measured thermal response of the ocean. This response is uncertain, and they took that uncertainty into account, which means that their estimate of the solar feedback factor is itself uncertain. However, the end result of the uncertainty analysis is that it is most probable that the factor is somewhat less than the un-corrected solar output, and it is very improbable that the feedback factor is greater than at most 1.5 times solar forcing. To explain the warming using solar only or even majority solar, you would need a MUCH larger effective forcing, as I said.
Question: If this was your boss, would you try to publish an AGW sceptic paper?
Ah yes. When all your "scientific" arguements have been disproven, retreat to vague allegations of bias.
Sorry, if you think there's something wrong with the science, say what it is and be prepared to defend it. You've failed on all fronts so far (and you apparently still haven't even read the papers I cited, since some of them deal with Svensmark).
I don't get what you're trying to accomplish. I'm not talking about TSI. As far as I know, no one is talking about TSI except you just now.
You are talking about TSI, whether directly or through its modulation of cosmic rays. The fact is, TSI trends have been flat for over 50 years despite continued warming, and cosmic ray trends also don't agree with the warming.
Svensmark has a nice hypothesis, that fits extremely well with the historical record, and is testable.
It's been tested and it's wrong.
Oh, and yes, they were indeed quite strong. If we use sun spots as the proxy, the solar cycles in the second half of the 20th century were actually the strongest combined in several hundred years (since measurements began).
Solar output which is high but flat still doesn't explain increasing temperatures, even when you introduce time lag into the oceans. Indeed, if you throw in an unknown multiplying factor to solar output (representing, say, cosmic ray cloud feedbacks or any other solar feedback you might imagine) and try to estimate how big that factor can be, you find out that it's equal to or smaller than solar output alone. This was done, for instance, in Tomassini et al. last year. Basically, if you make the amplification big enough to explain the latter 20th century, you get the early 20th century wrong, and vice versa.
Hi again. Thanks for your questions. It's refreshing to see some honest questions unaccompanied by snide allegations about socialism and funding bias.
According to your data, there were no measurements taken of atmospheric carbon dioxide until 1958.
There are no direct instrumental measurements before then, but there are ice core measurements of past CO2 which was trapped there in gas bubbles.
Your temperature graph shows that the temperature has gone from about -0.2C in 1880 to 0.6C in 2000. That's about 0.8C change in 120 years. Is this really cause for concern?
By itself, no. It's the potential larger warming in the future which is cause for concern; as CO2 emissions accelerate and as the oceans warm from earlier greenhouse effects, could see a further warming of several degrees over a similar time period.
In 120 years of the heaviest industrial human activity in history, the temperature went up only 0.8 degrees Celsius.
CO2 levels have only increased by about 35% over 150 years. We're on course to double them in the next 50 years! Furthermore, the climate system shows a lagged response: because of the thermal inertial of the oceans, the greenhouse effect we experience today is not fully realized at the surface, because some of the heat goes into the oceans. As the oceans warm, we eventually see the full effect of the warming.
I can't even find "the 1940s" on your ice core sample graph, so it's not very useful.
The 1940s are in the graph, although the horizontal scale is compressed. Although it's hard to pick out exactly which data points are the 1940s, you can clearly see that the 1940s were not the period when CO2 levels were at their highest; that is today.
Compare with this statement, which contains data: "Atmospheric carbon dioxide measurements started in 1958. In 1958, carbon dioxide levels were about 315ppm. The level is now up to about 380ppm. That's an about a 20% increase in 50 years. In the same time, global temperature has gone up about 0.6C, an increase of about 1%."
This comparison is slightly misleading. You shouldn't compare percent increase in CO2 to percent increase in temperature. Temperature responds to radiative forcing (heat), not CO2 levels directly. Radiative forcing is logarithmic in CO2 levels, so you need to look at changes in log CO2. More importantly, you need to look at changes in log CO2 relative to other sources of radiative forcing. The forcing due to at 280->380 ppm increase in CO2 works out to be about 2 watts per square meter (see the IPCC report), compared to an overall planetary flux of, I forget, something like 300-400 W/m^2. So we're looking at roughly a 1% increase in forcing and a 1% increase in absolute temperature.
We've only got 50 years of atmospheric carbon dioxide measurements.
We have 50 years of direct instrumental measurements, but we have 800,000+ years of good CO2 data (see Luethi et al. in Nature this year), and longer periods of less good data. (You note that CO2 levels were higher in the distant past, so obviously you believe we've got more than 50 years of data.) Current CO2 levels are higher than they've been at any time in the last 800,000 years! (And probably for longer than that, based on our less accurate data.)
Isn't it a bit early to be calling it a catastrophe? Shouldn't we keep measuring it for a few more decades and see what happens?
Measuring CO2 isn't going to tell us much; we know from economics that it's going to increase a lot, and measuring it will only confirm that fact. If you're suggesting that we need to keep measuring it to make sure it's ours, there are about five independent lines of evidence that say it is, which I can go into detail about. That's really an incontrovertible fact of the science.
My argument has nothing to do with Mars. I have not claimed that CO2 is the only source of warming, and I certainly haven't claimed it's the only source of warming on all planets. I do claim that it's been the major source of global warming on Earth for the last 50 years or so.
In fact, we don't know that global warming is happening on Mars; the warming seems mostly concentrated near its south pole, and has been attributed to changes in global dust storm activity.
No, they were not "quite strong", in terms of how much heat flux you actually need to explain the observed warming. Solar trends past 1950 or so are roughly AN ORDER OF MAGNITUDE too small to explain the subsequent warming; the change in TSI is just a few tenths of a watt per square meter, and radiative forcing is a quarter of TSI. Furthermore cycles 22 and 23 were WEAKER than 21, on average, although 22 had some brief peaks.
And of course, all your sources are unimpeachable, deeply imbued with nothing but the essence of honesty, integrity, impartiality, and infallibility.
This is not a he said/she said debate over who is "credible". You claim that you want to discuss facts and science. I gave specific reasons WHY those papers are wrong, and I can give much more detail than that; I've read almost every major climate sensitivity paper published in the last 5 years. You've got nothing but "I don't believe you". Well, cut the crap about being open to scientific discussion then.
If you've got a problem with THE SCIENCE, say what it is. Don't just sit around slinging vague accusations of bias and dishonesty as an excuse to ignore the scientific literature.
If it's so cut and dried then please, by all means, enlighten me. Provide your proof. Back it up with data. Show me the model that predicts, within reasonable limits, the past 100-200 years of weather trends and also predicts the next 100 years.
I already cited the IPCC report, which references pretty much every important study in this field. You ignored it.
Show me that it's all based on CO2,
It's not all based on CO2, but CO2 has been the largest contributor since the latter half of the 20th century, and barring some truly dramatic and unusual change in natural sources, it's going to continue growing as an influence.
Lastly, if you want a pretty thorough list of scientists who are skeptical of warming -- or at least skeptical that it's anthropocentric -- go here. I'd love to see a post debunking all of them as hopeless crackpots.
Give me a break. I am not going to write a personal rebuttal to every single person who has expressed an opinion on the matter, just to convince somebody on Slashdot who has already stated that they intentionally intend to ignore the mainstream scientific literature. In particular, when someone just states an opinion and doesn't give any science to back it up, there's nothing to rebut. I've already given you some specific criticisms of a few papers. If you want to single out a few which you think are the most devastating critiques of AGW, bring them up and we can discuss them.
I'll present you with the following situation: you have just ingested a cup of colorless, odorless, tasteless fluid which you believed to be water. Suddenly, three complete strangers run into the room. The first carries a syringe and says "I am an expert in poisons! You just drank a deadly poison! Inject yourself right now with this syringe or the poison will kill you in a month!"
This is your usual false analogy, which presumes that we have literally zero knowledge and that all outcomes and loss functions are equally plausible.
An intelligent person might conclude that the smartest thing to do would be to find out which one of them is right before doing anything at all.
We are never going to have certainty. Sorry, too bad. Life requires us to make decisions anyway. And while we don't have certainty, we do know, for instance, that 3 C of warming and 3 C of cooling by 2100 are not equally likely outcomes. If something we learn tomorrow is likely to overturn everything we know, you might have a point, but that too doesn't represent our true state of knowledge of the climate system. We learn about it slowly and it takes many years of data to appreciably change estimates of a noisy system which are already based on many years of data.
Instead, you're suggesting that we do something in the hopes that (a) it's the right thing to do, (b) it's worth the cost, and (c) it isn't overlooking some crucial flaw that will cause even greater damage. You have not satisfied any of these criteria beyond a reasonable reproach.
No, you simply dismiss the vast amount of science and economics that has been done. As far as I can tell, you haven't even read any of it, and thus take the "he said/she said" position that anything that anybody says is equally plausible.
What you don't understand is this: I am open to being convinced,
No, you're not. You may believe it, but you've already said that you're willing to dismiss pretty much the entire scientific literature by virtue of it having been cited by the IPCC. Well, if you're going to ignore anything that they cite, you're going to ignore almost all of the science. It's just an excuse for you to dismiss arbitrarily large amounts of evidence, and then you ironically keep parading around how "unbiased" and "open minded" you are.
The premise of insurance is that it guarantees to protect you from a potential threat. You can't guarantee the threat
On the contrary, we have considerable evidence that CO2 emissions under business-as-usual will lead to between 2 and 5 degrees of warming this century, depending on how much "business as usual" ends up emitting.
but, and most importantly, you can't guarantee the insurance will actually protect against the potential threat.
Again, to the contrary, we have even more considerable evidence that this threat is due to increases in CO2 levels, and therefore reducing the rate at which they are emitted will reduce the threat.
Indeed, if you're really wrong, implementing the insurance could exacerbate the situation. More study is needed.
"More study" is always needed. That doesn't change the fact that we already know enough to know that there is a risk, and it doesn't change the fact that we learn slowly about the climate system, so delaying 50 years to really nail down climate sensitivity is not a prudent option.
And what about the man made contribution of CO2 compared to natural contributions of CO2 in the atmosphere?
Man-made CO2 has increased the total amount of CO2 in the atmosphere by about 35% over pre-industrial levels.
When water reaches saturation in the atmosphere, does the ensuing rain not scrub some of the CO2 out of the atmosphere?
Not really. Precipitation scrubs particulate matter, but not so much well-mixed gases like CO2. There are natural sinks of CO2: on land, plants absorb it during photosynthesis, and in the ocean, it dissolves into seawater. Currently, the land and ocean sinks each take up about 25% of the CO2 that humans are emitting, leaving 50% of our emissions remaining in the atmosphere to accumulate.
If not, then can the remaining CO2 actually continue to increase the effect by a few more degrees without the presence of the water vapor?
I don't understand what you're asking here.
In all of the "discussions" about the greenhouse gasses, why is not water vapor mentioned?
Water vapor is mentioned all the time; its greenhouse effect is the largest feedback amplifying the greenhouse effect of CO2. But it's not mentioned as the cause of global warming, because warming is not caused by increases in water vapor. However, warming due to other causes (both human and natural) is amplified by water vapor.
Basically, the amount of water vapor in the atmosphere is controlled by the Earth's temperature. For a given temperature, the water vapor content can't increase substantially, because the Earth is in evaporation-precipitation balance and excess vapor rains out. But if something else raises the temperature of the Earth, then that changes the balance, allows more water vapor to evaporate, and amplifies the warming due to other causes. For that reason, water vapor is known as a "feedback" of warming, not a "forcing" of warming like CO2, solar irradiance, etc.
The core of the Earth is hot.
The core of the Earth is hot, but the amount of heat being received at the Earth's surface from the core has not increased appreciably. We can measure this via thermometers inserted into boreholes dug into the Earth's crust.
The question is not whether there are other sources of heat in the climate system, but whether any of those sources have increased in a way that can account for the observed increase in temperature.
But for some reason, it is man made CO2 in the atmosphere that gets all the blame for heating the oceans and the permafrost lands which is causing ice to melt.
"For some reason"? The reason is that physics predicts this will happen due to CO2, and that other sources of warming do not agree with the rate, magnitude, or timing of the observed heating in the Earth system. It's not due to the Earth's core heating up; we can measure that over time and as a function of depth, and we see heat penetrating down from the surface, not up from below. Ditto for the seabed floor, or the oceans themselves: they're absorbing heat from the surface, not radiating it. We can go on and on like this, but the point is that scientists have studied both natural and human causes of warming for a long time. The attribution of the current warming to humans is not a whim, it's the result of testing all these hypotheses and picking the one that best agrees with the data.
Your claims about the Sun are pretty much the opposite of what actually happened. Read the papers I cited earlier. In fact, solar activity did not increase appreciably for decades, right when we saw the most warming post-1970.
Slashdot Mirror
Seriously, I wish people would stop getting so shocked about this.
Climatologists are not unaware that the climate has changed in the past. The issue is that climate is currently changing faster than it would have without human input, and that larger and faster changes are likely if we continue to increase our input to the climate system.
I'm not complaining about anything. Go talk to the original poster.
Preferring OS X is relevant because if you want to buy a laptop with OS X, you're now stuck with a glossy screen.
You can't buy and connect any screen you want without serious modifications to the laptop. Adding an external display is not the point; it's a portable computer.
Despite the summary, authors aren't literally like sellers at an auction. They don't receive any money for their papers. For journals with page charges they have to pay to publish!
Publishers are only "bidders" in the sense that they are competing to have the best papers published in their journals. But they don't compete monetarily — as I said, they don't pay authors. They compete through prestige: authors (often) want their papers to be published in the most famous, widely read, influential journal. Prestige is determined by selective choice in what the journals choose to publish, which scientific niche they occupy, etc.
What do you want to bet that Gauss's teacher gave one of the three responses you listed, too?
If it does complain, just give it a hug.
The point is that the "stronger solar output" doesn't mean "strong enough, or with the correct time series behavior, to explain the warming we've seen", for reasons I have already exhaustively discussed.
You can cling to your claims only as long as you choose not to actually plug any numbers in and see what that kind of forcing predicts for the climate.
Who claims that solar output has had a dominant effect on the climate until 8-9 years ago?
Regarding the period of time over which solar hasn't been a dominant forcing, the IPCC says "between 1950 to 2005". Stott et al. say "the second half of the twentieth century". Foukal et al. say 30 years, although it should be noted that they're explicitly looking at satellite data which we only have for 30 years, and so can't give a number larger than that using that data. I suppose I can go dig for more explicit statements, but this is sufficient to indicate that I'm not the only one claiming that.
Currently neither of them can explain what we're seeing.
CO2 can easily explain the warming trend we've seen. If you're referring to the usual "we're experiencing global cooling" cliche, there isn't any evidence that the underlying long term trend has even changed beyond what can be expected from ordinary interannual natural variability.
even the wikipedia article on Svensmark's hypothesis has more info on the various claims and counter claims than you seem to display here
None of them get around the basic fact that you can't simultaneously match early 20th century and late 20th century temperature trends by appealing primarily to a feedback-amplified solar output, for the basic reason that the response doesn't look like the forcing. The result of the statistical analyses like the Tomassini et al. I mentioned boils down to the observation that if you amplify solar output enough to account for the late 20th century warming, you (a) get too much early 20th century warming and (b) the late warming still doesn't really match up in rate or magnitude when you take into account the ocean lag time (and its uncertainty). The only way you're going to do it is by postulating very different effects of cosmic rays on clouds at different time periods, which is not something that Svensmark himself has proposed.
Weird statement to make, since I just corrected you on that subject.
No, you didn't correct me. Solar trends have been basically flat for decades (which you still refuse to admit) — anything on the order of a few tenths of a W/m^2 is "flat" as far as the solar cycle or previous trends are concerned — and the solar cycles 22/23 are not high compared to any solar activity that has occurred in the last half century. You simply aren't going to explain a sharp increase in temperatures with solar output that hasn't increased.
(You make a serious scientific error when claiming "disproven" btw.
I meant exactly what I said.
No, the hypothesis is not falsified.
It has been, unless you postulate a weird nonlinear feedback constructed to have just the characteristics necessary to mask the fact that the cosmic ray feedback doesn't agree with the data. There is no physical mechanism which supports such a feedback, the supporters of the cosmic ray cloud connection themselves don't propose any such mechanism, and it's the last ad-hoc refuge of a failed theory.
There isn't enough data, but the data that exists is both in support as well as not.
There is enough data, and it clearly disagrees with solar output having a dominant effect on climate over the last 50 years.
... and thus we're back to having two competing hypotheses, both relying on unknown feedback mechanisms and neither having been tested enough.
Uh, no. We're talking about two competing hypotheses, one of which (solar) makes predictions which are wrong by an order of magnitude. The feedback mechanisms are not unknown — water vapor, lapse rate, ice albedo, cloud feedbacks, etc. have all long been studied. If you don't believe the individual feedbacks account for the majority of the total, the strength of the total feedback can be estimated from the data. If you try to apply different feedbacks to solar vs. everything else, no choice of amplifying solar feedback reproduces the data.
Now, please answer the question: If Hansen was your boss, would you publish an AGW-sceptic paper?
Yes, if I thought it was right. Now, since you claim to be such a big fan of science over politics, why don't you describe what's wrong with the science instead of resorting to vague allegations of bias.
(I've read most of the papers you've cited,
The hell you have. You don't even know what the solar trend looks like.
and also Svensmark's rebuttals of course.
Oh, fine, tell me what Svensmark's rebuttal is to Tomassini's estimate of the solar amplification factor. (Clue: he doesn't have one.)
It's still a hypothesis with a better match,
Except for the fact that it completely fails to match the surface temperature and ocean heat data, with any feedback factor you care to choose. And if you throw out the surface temperature data, your claim is even more nonsensical since you can't compare solar data to it either.
and more Occam'ish,
"The Sun affects cosmic rays which affect clouds which affect reflect sunlight" is not "more Occam'ish" than "CO2 absorbs longwave radiation", especially considering how few links in the former chain are directly supported by evidence.
than the IPCC CO2 wildly spiralling feedback nonsense)
Solar-cosmic ray-cloud warming involves all the same feedbacks that CO2 warming does, plus one extra feedback. When the feedbacks apply to CO2 warming, they're "nonsense", but when they apply to solar warming,
P.S. The IPCC didn't invent the CO2 greenhouse effect or climate feedbacks.
P.S.:
I'm sorry, but posting your own (faulty) speculation is a bad argument.
P.S. This isn't my "speculation", this is published research. If you bothered to read anything other than Svensmark, you would know this. Why you continue to cling to your disproven claims, I don't know.
(There is a 4 as well, of course, and that is that anything that's verified against surface temperatures is in doubt)
Well that would include your theory too, then. But that aside, the surface temperature record is not untrustworthy, for reasons I explained two days ago, and which you continue to ignore.
The only way you can persist with your claims is by waiting long enough, so that you hope everyone forgets your claims were disproven. It's getting to be really pathetic.
1) No the trends aren't flat
They're not flat, but they are very, very small — certainly far smaller than the trends in the preceding 50-100 years. As I've said, it's only changed by a few tenths of a watt per square meter. You can find the trends in some of the papers I've mentioned. I Googled around for a web version and found this. I don't know which reconstruction it is (it looks like Lean to me), but they all show this flattening.
2) I disagree with "it" having been tested
You disagree because you refuse to read the papers which test "it", including but not limited to the ones I've cited.
3) We don't know enough about ocean currents to claim that time lag cannot explain what we're seeing
Yes, we do. The paper I mentioned explicitly calibrated the time lag to the measured thermal response of the ocean. This response is uncertain, and they took that uncertainty into account, which means that their estimate of the solar feedback factor is itself uncertain. However, the end result of the uncertainty analysis is that it is most probable that the factor is somewhat less than the un-corrected solar output, and it is very improbable that the feedback factor is greater than at most 1.5 times solar forcing. To explain the warming using solar only or even majority solar, you would need a MUCH larger effective forcing, as I said.
Question: If this was your boss, would you try to publish an AGW sceptic paper?
Ah yes. When all your "scientific" arguements have been disproven, retreat to vague allegations of bias.
Sorry, if you think there's something wrong with the science, say what it is and be prepared to defend it. You've failed on all fronts so far (and you apparently still haven't even read the papers I cited, since some of them deal with Svensmark).
I don't get what you're trying to accomplish. I'm not talking about TSI. As far as I know, no one is talking about TSI except you just now.
You are talking about TSI, whether directly or through its modulation of cosmic rays. The fact is, TSI trends have been flat for over 50 years despite continued warming, and cosmic ray trends also don't agree with the warming.
Svensmark has a nice hypothesis, that fits extremely well with the historical record, and is testable.
It's been tested and it's wrong.
Oh, and yes, they were indeed quite strong. If we use sun spots as the proxy, the solar cycles in the second half of the 20th century were actually the strongest combined in several hundred years (since measurements began).
Solar output which is high but flat still doesn't explain increasing temperatures, even when you introduce time lag into the oceans. Indeed, if you throw in an unknown multiplying factor to solar output (representing, say, cosmic ray cloud feedbacks or any other solar feedback you might imagine) and try to estimate how big that factor can be, you find out that it's equal to or smaller than solar output alone. This was done, for instance, in Tomassini et al. last year. Basically, if you make the amplification big enough to explain the latter 20th century, you get the early 20th century wrong, and vice versa.
Hi again. Thanks for your questions. It's refreshing to see some honest questions unaccompanied by snide allegations about socialism and funding bias.
According to your data, there were no measurements taken of atmospheric carbon dioxide until 1958.
There are no direct instrumental measurements before then, but there are ice core measurements of past CO2 which was trapped there in gas bubbles.
Your temperature graph shows that the temperature has gone from about -0.2C in 1880 to 0.6C in 2000. That's about 0.8C change in 120 years. Is this really cause for concern?
By itself, no. It's the potential larger warming in the future which is cause for concern; as CO2 emissions accelerate and as the oceans warm from earlier greenhouse effects, could see a further warming of several degrees over a similar time period.
In 120 years of the heaviest industrial human activity in history, the temperature went up only 0.8 degrees Celsius.
CO2 levels have only increased by about 35% over 150 years. We're on course to double them in the next 50 years! Furthermore, the climate system shows a lagged response: because of the thermal inertial of the oceans, the greenhouse effect we experience today is not fully realized at the surface, because some of the heat goes into the oceans. As the oceans warm, we eventually see the full effect of the warming.
I can't even find "the 1940s" on your ice core sample graph, so it's not very useful.
The 1940s are in the graph, although the horizontal scale is compressed. Although it's hard to pick out exactly which data points are the 1940s, you can clearly see that the 1940s were not the period when CO2 levels were at their highest; that is today.
Compare with this statement, which contains data: "Atmospheric carbon dioxide measurements started in 1958. In 1958, carbon dioxide levels were about 315ppm. The level is now up to about 380ppm. That's an about a 20% increase in 50 years. In the same time, global temperature has gone up about 0.6C, an increase of about 1%."
This comparison is slightly misleading. You shouldn't compare percent increase in CO2 to percent increase in temperature. Temperature responds to radiative forcing (heat), not CO2 levels directly. Radiative forcing is logarithmic in CO2 levels, so you need to look at changes in log CO2. More importantly, you need to look at changes in log CO2 relative to other sources of radiative forcing. The forcing due to at 280->380 ppm increase in CO2 works out to be about 2 watts per square meter (see the IPCC report), compared to an overall planetary flux of, I forget, something like 300-400 W/m^2. So we're looking at roughly a 1% increase in forcing and a 1% increase in absolute temperature.
We've only got 50 years of atmospheric carbon dioxide measurements.
We have 50 years of direct instrumental measurements, but we have 800,000+ years of good CO2 data (see Luethi et al. in Nature this year), and longer periods of less good data. (You note that CO2 levels were higher in the distant past, so obviously you believe we've got more than 50 years of data.) Current CO2 levels are higher than they've been at any time in the last 800,000 years! (And probably for longer than that, based on our less accurate data.)
Isn't it a bit early to be calling it a catastrophe? Shouldn't we keep measuring it for a few more decades and see what happens?
Measuring CO2 isn't going to tell us much; we know from economics that it's going to increase a lot, and measuring it will only confirm that fact. If you're suggesting that we need to keep measuring it to make sure it's ours, there are about five independent lines of evidence that say it is, which I can go into detail about. That's really an incontrovertible fact of the science.
My argument has nothing to do with Mars. I have not claimed that CO2 is the only source of warming, and I certainly haven't claimed it's the only source of warming on all planets. I do claim that it's been the major source of global warming on Earth for the last 50 years or so.
In fact, we don't know that global warming is happening on Mars; the warming seems mostly concentrated near its south pole, and has been attributed to changes in global dust storm activity.
No, they were not "quite strong", in terms of how much heat flux you actually need to explain the observed warming. Solar trends past 1950 or so are roughly AN ORDER OF MAGNITUDE too small to explain the subsequent warming; the change in TSI is just a few tenths of a watt per square meter, and radiative forcing is a quarter of TSI. Furthermore cycles 22 and 23 were WEAKER than 21, on average, although 22 had some brief peaks.
And of course, all your sources are unimpeachable, deeply imbued with nothing but the essence of honesty, integrity, impartiality, and infallibility.
This is not a he said/she said debate over who is "credible". You claim that you want to discuss facts and science. I gave specific reasons WHY those papers are wrong, and I can give much more detail than that; I've read almost every major climate sensitivity paper published in the last 5 years. You've got nothing but "I don't believe you". Well, cut the crap about being open to scientific discussion then.
If you've got a problem with THE SCIENCE, say what it is. Don't just sit around slinging vague accusations of bias and dishonesty as an excuse to ignore the scientific literature.
If it's so cut and dried then please, by all means, enlighten me. Provide your proof. Back it up with data. Show me the model that predicts, within reasonable limits, the past 100-200 years of weather trends and also predicts the next 100 years.
I already cited the IPCC report, which references pretty much every important study in this field. You ignored it.
Show me that it's all based on CO2,
It's not all based on CO2, but CO2 has been the largest contributor since the latter half of the 20th century, and barring some truly dramatic and unusual change in natural sources, it's going to continue growing as an influence.
Lastly, if you want a pretty thorough list of scientists who are skeptical of warming -- or at least skeptical that it's anthropocentric -- go here. I'd love to see a post debunking all of them as hopeless crackpots.
Give me a break. I am not going to write a personal rebuttal to every single person who has expressed an opinion on the matter, just to convince somebody on Slashdot who has already stated that they intentionally intend to ignore the mainstream scientific literature. In particular, when someone just states an opinion and doesn't give any science to back it up, there's nothing to rebut. I've already given you some specific criticisms of a few papers. If you want to single out a few which you think are the most devastating critiques of AGW, bring them up and we can discuss them.
I'll present you with the following situation: you have just ingested a cup of colorless, odorless, tasteless fluid which you believed to be water. Suddenly, three complete strangers run into the room. The first carries a syringe and says "I am an expert in poisons! You just drank a deadly poison! Inject yourself right now with this syringe or the poison will kill you in a month!"
This is your usual false analogy, which presumes that we have literally zero knowledge and that all outcomes and loss functions are equally plausible.
An intelligent person might conclude that the smartest thing to do would be to find out which one of them is right before doing anything at all.
We are never going to have certainty. Sorry, too bad. Life requires us to make decisions anyway. And while we don't have certainty, we do know, for instance, that 3 C of warming and 3 C of cooling by 2100 are not equally likely outcomes. If something we learn tomorrow is likely to overturn everything we know, you might have a point, but that too doesn't represent our true state of knowledge of the climate system. We learn about it slowly and it takes many years of data to appreciably change estimates of a noisy system which are already based on many years of data.
Instead, you're suggesting that we do something in the hopes that (a) it's the right thing to do, (b) it's worth the cost, and (c) it isn't overlooking some crucial flaw that will cause even greater damage. You have not satisfied any of these criteria beyond a reasonable reproach.
No, you simply dismiss the vast amount of science and economics that has been done. As far as I can tell, you haven't even read any of it, and thus take the "he said/she said" position that anything that anybody says is equally plausible.
What you don't understand is this: I am open to being convinced,
No, you're not. You may believe it, but you've already said that you're willing to dismiss pretty much the entire scientific literature by virtue of it having been cited by the IPCC. Well, if you're going to ignore anything that they cite, you're going to ignore almost all of the science. It's just an excuse for you to dismiss arbitrarily large amounts of evidence, and then you ironically keep parading around how "unbiased" and "open minded" you are.
The premise of insurance is that it guarantees to protect you from a potential threat. You can't guarantee the threat
On the contrary, we have considerable evidence that CO2 emissions under business-as-usual will lead to between 2 and 5 degrees of warming this century, depending on how much "business as usual" ends up emitting.
but, and most importantly, you can't guarantee the insurance will actually protect against the potential threat.
Again, to the contrary, we have even more considerable evidence that this threat is due to increases in CO2 levels, and therefore reducing the rate at which they are emitted will reduce the threat.
Indeed, if you're really wrong, implementing the insurance could exacerbate the situation. More study is needed.
"More study" is always needed. That doesn't change the fact that we already know enough to know that there is a risk, and it doesn't change the fact that we learn slowly about the climate system, so delaying 50 years to really nail down climate sensitivity is not a prudent option.
And what about the man made contribution of CO2 compared to natural contributions of CO2 in the atmosphere?
Man-made CO2 has increased the total amount of CO2 in the atmosphere by about 35% over pre-industrial levels.
When water reaches saturation in the atmosphere, does the ensuing rain not scrub some of the CO2 out of the atmosphere?
Not really. Precipitation scrubs particulate matter, but not so much well-mixed gases like CO2. There are natural sinks of CO2: on land, plants absorb it during photosynthesis, and in the ocean, it dissolves into seawater. Currently, the land and ocean sinks each take up about 25% of the CO2 that humans are emitting, leaving 50% of our emissions remaining in the atmosphere to accumulate.
If not, then can the remaining CO2 actually continue to increase the effect by a few more degrees without the presence of the water vapor?
I don't understand what you're asking here.
In all of the "discussions" about the greenhouse gasses, why is not water vapor mentioned?
Water vapor is mentioned all the time; its greenhouse effect is the largest feedback amplifying the greenhouse effect of CO2. But it's not mentioned as the cause of global warming, because warming is not caused by increases in water vapor. However, warming due to other causes (both human and natural) is amplified by water vapor.
Basically, the amount of water vapor in the atmosphere is controlled by the Earth's temperature. For a given temperature, the water vapor content can't increase substantially, because the Earth is in evaporation-precipitation balance and excess vapor rains out. But if something else raises the temperature of the Earth, then that changes the balance, allows more water vapor to evaporate, and amplifies the warming due to other causes. For that reason, water vapor is known as a "feedback" of warming, not a "forcing" of warming like CO2, solar irradiance, etc.
The core of the Earth is hot.
The core of the Earth is hot, but the amount of heat being received at the Earth's surface from the core has not increased appreciably. We can measure this via thermometers inserted into boreholes dug into the Earth's crust.
The question is not whether there are other sources of heat in the climate system, but whether any of those sources have increased in a way that can account for the observed increase in temperature.
But for some reason, it is man made CO2 in the atmosphere that gets all the blame for heating the oceans and the permafrost lands which is causing ice to melt.
"For some reason"? The reason is that physics predicts this will happen due to CO2, and that other sources of warming do not agree with the rate, magnitude, or timing of the observed heating in the Earth system. It's not due to the Earth's core heating up; we can measure that over time and as a function of depth, and we see heat penetrating down from the surface, not up from below. Ditto for the seabed floor, or the oceans themselves: they're absorbing heat from the surface, not radiating it. We can go on and on like this, but the point is that scientists have studied both natural and human causes of warming for a long time. The attribution of the current warming to humans is not a whim, it's the result of testing all these hypotheses and picking the one that best agrees with the data.
Your claims about the Sun are pretty much the opposite of what actually happened. Read the papers I cited earlier. In fact, solar activity did not increase appreciably for decades, right when we saw the most warming post-1970.