Slashdot Mirror
1981 Paper's Predictions for Global Temperatures Spot-On
Layzej writes "The Register reports on a paper published in Science in 1981 projecting global mean temperatures up to the year 2100. 'When the 1981 paper was written, temperatures in the northern hemispheres were declining, and global mean temperatures were below their 1940 levels. Despite those facts, the paper's authors confidently predicted a rise in temperature due to increasing CO2 emissions.' The prediction turns out to be remarkably accurate — even a bit optimistic. The article concludes that the 1981 paper is 'a nice example of a statement based on theory that could be falsified and up to now has withstood the test.'"
I'm not commenting on the climate one way or the other, but when you have dozens of different predictions over the years is it really surprising that a couple of them happened to hit the mark? Don't forget the Global Cooling sentiment which was around just a couple of years before this article came out...
Care to cite one? Since it sounds like you're so well-informed.
Dislike the Electoral College? Lobby your state to join the National Popular Vote Interstate Compact.
The eighties was 30 years ago?
Shit I'm old.
You can never know everything, and part of what you do know will always be wrong. Perhaps even the most important part.
Tells you about the rigor of climate science, that's for certain.
HBI's Law: Frequency of calling others Nazis is directly correlated with the likelihood of the accuser being Communist.
well... y'know what? even brownian motion gets it right if there's enough molecules. the trick is in being able to spot the one molecule that pops out at the right place at the right time, and this is no different, really.
out of hundreds of articles on climate theory predictions, at least _one_ of them had to get it right. the problem is this, however: that correctness could only be spotted in retrospect, and so doesn't actually help us *unless* the article goes on to predict a bit further into the future, and even then it *still* doesn't really help us to solve the problem (which is that action needs to be taken) because, once again, people really won't listen until it's yet *again* too late.
all of which goes to just highlight that the problem is not the predictions, but that nothing's been done *about* those predictions. so that just leaves it to us to DO something, as individuals. which is why i'm actually doing something, in two areas that i am interested in: cars - http://lkcl.net/ev - and computers - http://rhombus-tech.net./ what are _you_ doing, slashdot reader?
I am very far from being a specialist in this topic. The The Register article seems to imply that global warming must be true, given that there was ONE paper in 80s already anticipating it. That is not necessarily true. The prediction can be result of pure chance in a possibly erratic research study (I have no clue if that is the case or not). One could perhaps make an stronger statement in that direction if MANY papers anticipated global warming (possibly using different models).
As an obnoxiously misinformed dumbass, I'm willing to throw out any scientific evidenced based for reasons that border on the absurd.
I read that another unrelated study was wrong, and that the scientists were on big climate's payroll. Therefor, global warming, and by extension this scientifically proven theory are also wrong.
Now if you'll excuse me, I've got to post this brilliant analysis on my blog.
The warming of due to CO2 is a scientific fatc. Please REPEAT the experiments showing this.
And if you take pretty much the same data, over time, and show when the sunspot activity grew & shrank, I bet you would show that the temperature rise pretty much is spot on with the rise in geomagnetic activity from the sun, which is what heats & cools this rock we call a planet! But, considering the stupidity of "modern" man, the only thing they will read out of this is that temperatures are rising! Back when I was in high school in the 70's, they were talking about a mini ice age....but unless you read into the article, they finally mentioned the LACK of sunspots & the cooling of the sun at the time.
So, in yesterday's story about predicting the collapse of civilization, multiple posters snarked about how convenient it is to make predictions about what will happen 30 years from now, 'cause no one will remember you made those predictions--so you'll never be called to account for your oh-so-incorrect doomsday predictions.
I now calmly await for yesterday's posters to issue "I can see now that I was wrong" statements.
"Don't blame the log for the fire." --Andrew Ratshin
I would also be interested in knowing about other predictions, in particular predictions with specific numbers backed by plausible theoretical models, published in a respectable venue like Science or Nature (or some more specialized but still solidly peer-reviewed journal).
If indeed it turns out that there were a few hundred such models/predictions, and one turned out to be close to right, that would not be super impressive. But I'm not able to find those hundreds, if they exist...
10 PRINT CHR$(205.5+RND(1)); : GOTO 10
I wish coversation around this topic would shift from debate about whether or not the climate is changing and may in fact change dramatically over the course of several decades, and whether or not humans activities have an impact on the climate to a productive conversation about how to best react to changing climate and use it productively. It is obvious to me that where I live (Minnesota), the mean temperatures are rising and the growing seasons are getting longer. Shit, I had my vegetable seeds sprouting and even had them outdoors some days, early in March, in Minnesota! I am also growing a dwarf bananna tree that has made it through two winters here. I guess my point is, I think it would be great if people would quit arguing about empirical facts (such as there is more CO2 in the atmosphere than ever before during modern human civilization); and start wondering about how to react to the changes that might be brought about in this altered environment.
Koalas. They're telepathic. Plus, they control the weather. -Margaret
I love extrapolation.
http://xkcd.com/605/
Seriously, things don't go in a straight line forever. Further, they were quite totally wrong, in that their predictions were too low. I don't know what the big deal is, other than AGW people glorying in their own selection bias.
From the Hansen study:
"Political and economic forces affecting energy use and fuel choice make it unlikely that the CO2 issue will have a major impact on energy policies until convincing observations of the global warming are in hand."
thegodmovie.com - watch it
What were the other predictions? How do they relate to scientific observation? How did you find out about them? Are you sure you're not engaging in paranoid delusion?
For some reason, Google does not have a good index of websites from the 70s. I need to find an old copy of Lycos or Aliweb...
Which part has been a correct prediction? There was warming at the end of the 20th century.
Obvious warming due to CO2? The warming has been less than the minimum prediction of the IPCC. There are other theories, in particular, solar activity. The data doesn't support either theory convincingly.
Drought prone regions? No more so than usual.
Sea rise due to collapsing Antarctic ice sheet? The ice on the continent has been increasing. Melting sea ice doesn't increase the sea level.
Opening the Northwest Passage? Arctic sea ice is above normal right now.
Other than some warming at the end of the last century, Hansen's predictions haven't come true yet.
"a nice example of a statement based on theory that could be falsified and up to now has withstood the test."
Just wait till we finally reach a double of atmospheric CO2 values, at which point we'll get to see if the predictions Svante Arrhenius made in the late 19th / early 20th century pan out.
If the quantity of carbonic acid in the air should sink to one-half its present percentage, the temperature would fall by about 4 degrees; a diminution to one-quarter would reduce the temperature by 8 degrees. On the other hand, any doubling of the percentage of carbon dioxide in the air would raise the temperature of the earth's surface by 4 degrees; and if the carbon dioxide were increased fourfold, the temperature would rise by 8 degrees.
Although the sea, by absorbing carbonic acid, acts as a regulator of huge capacity, which takes up about five-sixths of the produced carbonic acid, we yet recognize that the slight percentage of carbonic acid in the atmosphere may by the advances of industry be changed to a noticeable degree in the course of a few centuries.
So about 8 years ago I moved from Minnesota to Northern Virginia for work. And one of the aspects of culture shock was that I was now living with, befriending and enjoying my time with folks from all over the country who had moved to the DC area for work. Many friends from Texas and Pennsylvania specifically. I even roomed with several of them and one thing really bothered me: they did not recycle. So I kept doing my own recycling and trying to help them out to no avail. This was quite different from Minnesota where it was stressed when we were young that it was important. You might call it common sense or indoctrination or nanny state or whatever your political views tell you to but that's just the way it was largely. And the reason was that the Earth is a precious resource.
So, being an avid Slashdotter, I was fairly in tune with the Global Warming debate and would often talk to my new friends about it. Every single one of them either didn't want to hear it or thought I was an idiot. They seemed to only listen when I would bring up news items lending credibility to the absence of climate change. Then they asserted there was climate change but it is natural and so on and so forth. To this day, my friend from Texas does not recycle in his home. His Korean wife has asked me not to discuss global warming around her and continually asserts it was proven wrong years ago. My friend from Texas, being quite a bit smarter now likes to talk about what we can do about it without him having to alter his lifestyle at all. The reason for it is unimportant to him, now he just accepts that it's happening for some reason and how can we put something in space that can block the sun partially while maintaining a synchronous orbit around the sun between it and Earth. It's not that that is a simpler solution than reducing your personal carbon footprint but instead it's one that doesn't require government intervention (which he views as the ultimate evil) and doesn't require him to change.
So what do you do when you read news about this, do you whip out your biggest "I told you so" font and e-mail it out to your friends until they get tired of it? I mean, I can't even politely offer to collect the cans and bottles from one of my friend's parties and take them to the local recycling center. He's almost proud of his freedom to be able to send it to the dump. So I have two options. One is silence and apathy and the other is not having any friends in this area. Silence and apathy it is.
My work here is dung.
This paper tries to predict temperature changes based on multiple scenarios of CO2 ppm emissions.
There are 2 fundamental problems, however. 1) There were no uncertainty ranges given. We can't say that a 30% deviation from one of the scenarios is accurate or inaccurate without these ranges. 2) The actual CO2 ppm emissions do not fall within the bounds of any of the proposed scenarios.
All we can say, definitively, is that events transpired outside the bounds of any of the scenarios and the results were outside the prediction of any of the scenarios. I fail to see the significance here.
I love science. From the article:
Most predictions that are off by 30% aren't really considered "remarkably accurate".
I'm uncertain about this one (i.e. I'm not trying to troll). It's nice that the prediction does seem to chart well, and since the weather can't be accurately predicted 7 days in advance, any climate model that outperforms naive ones over 30 years is an achievement. Still, the point of the (recent) author is clear -- they're trying to emphasize that a warming trend is occurring and that people predicted it 30 years ago using "science" that is still sound -- at least some discussion of why a 30% error rate is acceptable should take place.
How many others didn't hit the mark? Can we see those numbers?
Since global warming seems to be a boon to Minnesota, do you mind setting up a couple of hundreds tents to house the inhabitants of a village in Mexico whose farms turned to dust and blew away?
here:
http://en.wikipedia.org/wiki/Global_cooling
The Kruger Dunning explains most post on
(TFA isn't about those 4999; it's about the one that was right.)
If you want to pick one and explain what their error was, that might be interesting, but I think it's going to be less interesting than looking at the guys who were more careful.
In the next story about how Copernicus' model of the solar system being confirmed, are you going to ask "What about the Pope's model?" and talk about that instead? Not saying it's pointless to laugh at the pope or anything, just that you sure are easily distracted.
"Believe me!" -- Donald Trump
Exactly, multiple models, each spewing out multiple scenarios, with some badass OLAP cubes or other kinds multidimensional array variable system, then thrown into a nice Montecarlo + Logit + Voodoo cruncher to see what comes out.
Actually, global warming MUST be true by definition because the Earth is warmer.
An environmentalist or (ecology-centric) view does not necessarily ask us to "revert back".
It simply demands that we direct some of our individual and collective energies and intelligence to
recognizing and respecting ecological complexity and services and physical reality on this planet, as we go about our business.
Where are we going and why are we in a handbasket?
It's easy to go revisit old wild-assed guesses and find some which are confirmed.
Hansen's prediction is widely considered one of the most influential models out there for climate change. As it turns out, he made four predictions based on various scenarios of energy use in the future. The one that the article is talking about happens to be his most pessimistic prediction. I had the pleasure of attending a talk given by him recently at the Conference on World Affairs.
It's been 30 years and he's still trying his utmost to get people in power to just listen.
Looking at figure 7 for instance and comparing to the UAH number for this march (the highest anomaly this year) at +0.11C it looks to me like we are still well inside the line of 1 deviation from natural variability. As for figure 6 it puts us well below the 'no energy growth' line for any month in 2012, when in fact I'm pretty sure humans are burning through energy at a far great rate in 2012 than in 1981. Maybe they meant it was spot on in how to calculate the effective radiating temperature of the earth, which was taken from someone's work in another paper.
Noting that the real world observations *didn't* match Hansen's predictions (they were higher than expected at first, and then plateaued), what can we conclude?
1) Oh noes! It's worse than we thought!
2) The model, including its central conceit, is wrong. Back to the drawing board.
Or:
3) Hansen's climate model was right but his emissions projections were wrong.
4) The model was "wrong", in the sense of having a climate sensitivity different from the real world, which is unsurprising because climate sensitivity was uncertain by about a factor of 50% before Hansen's paper. This observation cannot "invalidate the central conceit" (i.e., falsify the greenhouse effect) if it's consistent with the expected error bars.
5) You're an idiot, given all your moronic blathering in this threads about how modern climate change is indistinguishable from natural variation. That might be true if we had no observations of the sources of natural variation. But observations of cosmic rays and solar activity exclude a solar cause of the recent warming, observations of ocean heat uptake exclude an oceanic cause, etc. Saying "it's just an expected recovery from the Little Ice Age" is profoundly stupid, when you ignore what factors caused the LIA and its recovery, and whether they are acting today in the same way.
I would also be interested in knowing about other predictions, in particular predictions with specific numbers backed by plausible theoretical models
Here's one from the same researcher, from 7 years later, after spending half a decade of super-computer time simulating the warming.
.3 degrees Celsius.
To understand the graph, the red line (Hansen A) was calculated assuming and annual increase of atmospheric CO2 of 1.5% per year. The orange line (Hansen B) was calculated assuming that the annual increase of atmospheric CO2 would be constant, and the yellow line (Hansen C) was calculated assuming CO2 output would decrease so much after 1990 that by 2000 it would cease to increase. He was optimistic in the scenario.
You can also look at the first IPCC report from 1990 which predicted a rise of
"First they came for the slanderers and i said nothing."
When will politics react to what science already knew 30 years ago? What's the prediction for the lag, 50 years? 100 years?
This is really not a useful approach. In the case of climate you have complex models whose output can be distilled to a single series, namely global average temperature in a given year. The simplest model would be to take a curve fitting algorithm and find the simplest mathematical equation that fits your results. You can think of that as Occam's razor cutting away all the junk. More succinctly, it's bullshit. To be credible the model must have explanatory power. This is why climate models that use finite element models with energy balances and account for various phenomena are superior. There is reason to expect that these models will continue to hold in the future. The fitted equation isn't expected to have any particular accuracy outside the fitted region.
On a more on-topic note, the simplest anthropogenic climate change model says increased CO2 leads to increased solar radiation absorption leads to temperature change. Put in a number for each and you get a number out. But this leaves out other sources of climate change, in particular any feedback effects that would magnify or reduce climate change. If you believe that these can affect climate you need to include them, at least any which you consider significant. And to measure the accuracy you need to check the complete results (typically the temperature in whatever cells you have temperature readings for), not just the summarized global average temperature. In fact you would certainly consider a model more accurate if the global average temperature was off due to a hotspot in the Pacific ocean than one that had the global average right on but had the northern hemisphere freezing and the southern hemisphere boiling.
If, as the article suggests, a model from 1981 is spot on, that suggests that the factors considered since then are not important ones within the temperature ranges we've seen so far. That doesn't mean that will continue to be the case in the future; linear feedback effects would grow as the change from the baseline becomes greater, and there is quite a bit of speculation about non-linear feedback effects as well.
So no matter how far off he was, you'd have an ad hoc special pleading to explain it. That's a non-falsifiable hypothesis, just like astrology.
The central conceit isn't the greenhouse effect, the central conceit is that human CO2 emissions are *driving*, past all natural variation, an increase in global average temperature that will be catastrophic. We know the greenhouse effect is real, and we've got reasonable estimate as to what its contribution might be. We don't, however, have any reason to believe that the greenhouse effect of CO2 triggers a feedback effect in H2O, that overwhelms all other natural factors.
Tell you what. Take your GCM. Start the clock at 40000BC. Run it for 42000 years. Get to within 1%, without hard coding or curve fitting, and maybe you've got something. Until then, you've got no reason to believe that modern observations aren't within the bounds of natural variation.
So no matter how far off he was, you'd have an ad hoc special pleading to explain it. That's a non-falsifiable hypothesis, just like astrology.
I repeat point (5), you're an idiot. I never said that, but you just can't help fantasizing about the irrationality everyone but yourself.
I merely pointed out that there are hypotheses other than the false dichotomy you presented. Sure you, as an infallibly rational skeptic, can accept this fact.
The central conceit isn't the greenhouse effect, the central conceit is that human CO2 emissions are *driving*, past all natural variation, an increase in global average temperature that will be catastrophic.
"Catastrophic" is a non-falsifiable statement. I thought you were scientific?
We don't, however, have any reason to believe that the greenhouse effect of CO2 triggers a feedback effect in H2O, that overwhelms all other natural factors.
No reason to believe that, other than basic thermodynamics and observations of the water vapor content of the atmosphere. You haven't disproven thermodynamics, have you?
Tell you what. Take your GCM. Start the clock at 40000BC. Run it for 42000 years. Get to within 1%, without hard coding or curve fitting, and maybe you've got something.
Get to within 1% of what? And why is arbitrary request this a relevant test of anything?
Figure 6 predicts a 0.45 degrees Celsius rise from 1979 to 2012, which matches well with the Wood For Trees global temperature index. However, Figure 6 does not predict that all of that rise will occur prior to 1998, with a flat-to-falling trend since then. Indeed, since the model has an exponential behavior (due to feedback/"sensitivity", I'm guessing), it actually shows quite the opposite behavior, with very little rise early in the period, followed by a much greater (linearly-approximated) slope in the last decade. The conclusion is that this model got very lucky this year, and does not well reflect the underlying physics.
The greenhouse effect is real, the earth has warmed over the past 30 years (though not much, if at all, over the last 13), and human behavior may be contributing to this warming by contributing slightly to the greenhouse effect. However the model presented in this paper is not a good explanation for the details of this process, and therefore cannot be relied on to estimate the magnitude of AGW. It therefore has no value as a policy tool, never mind that it has nothing to say about the economic costs of proposed policy solutions (or even its hypothesized environmental impacts).
If humans are mostly water, and beer is mostly water, then humans must be mostly beer.
Hmm, just saw the above was posted as AC. I'm the "AC".
Very interesting to keep hearing all the info still coming on CO2 based warming. This theory seems to have been proven less plausible, with the solar cycle theory of warming a somewhat more sustainable cause
According to industry talking points...
Do you have any idea how long ago the physics of greenhouse gasses was discovered?
Sheesh, evil *and* a jerk. -- Jade
That's the rub though...the groups we hear about, including our buddy Algore, are constantly spouting that we need to sacrifice our economy for the sake of "mother earth". Not in those words, but that's the end result. But no, no we don't and we shouldn't. I'm all for conservation as long as it's not at the cost of economic and national prosperity.
Until then, you've got no reason to believe that modern observations aren't within the bounds of natural variation.
You keep repeating this fallacy. You seem to believe that just because the climate varied naturally in the past, present variation cannot be distinguished from natural variation. Natural variation isn't some unexplained statistical process, and attributing climate change doesn't arise from comparing current ranges of variation to past ranges of variation. Natural variation comes from physics. There aren't very many places where atmospheric heat can come from, and we can look in those places. Natural variability is due to specific mechanisms such as solar variations, ocean cycles, volcanism, etc. We have observed all those things during the modern global warming period, and all of them fail to explain the warming during that period, regardless of what past variations they can explain.
If one looked at a whole bunch of models from the 80s, and saw how they did on average, then you'd be looking at the typical assumptions that models made in the 80s, and how well those assumptions panned out. It is reverse cherry-picking and shifting the burden to instantly assume that the study was exceptional compared to the predictions of peers at the time. Basically you are saying that, to convince you, someone has to find all the models done in the 80s, and score them all. (I assume that "skeptics" wouldn't listen to the results of such a study, since they he who doesn't listen doesn't hear.)
The NAS report in 1979 was very clear -- an academic review done two years earlier, and whose predictions have also born out. Considering this is an academic review article of the science at the time, the burden of proof is on "skeptics" to show that the NAS report was actually an aberration. (Plausible, but also somewhat ludicrous, since that would imply that the NAS got the prediction correct, despite gross incompetence in analyzing the literature of the day.) As for the prediction of temperature rise from CO2 -- that was made over a hundred years ago, and nothing has changed except that the error bars have gotten a lot smaller, and alternative hypotheses for current warming have also been ruled out.
I'm sure some "skeptic" somewhere will be able to find some paper from the 80s whose predictions have not been born out, and thereby cast a pall over the entire climate science establishment -- but only because "skeptics" are really believers. Only "skeptics" peddle certainty in this debate -- along with extreme environmentalists.
Like all pain, suffering is a signal that something isn't right
Fake!! Typewriters didn't have proportional fonts in 1981!
(sorry Mr Donaldson, couldn't resist...)
https://www.accountkiller.com/removal-requested
I hate this topic, because we can't even predict the weather a week in advance. Attention Climate Scientists: I have no faith in you. Keep working...maybe someday...
Denier! Turn him in! Storm his house! Threaten his children! Call the IRS on him! Let all the assets of modern science destroy its enemies!
... NOT open a giant, polluting coal burning nerve gas factory and operate it for 150 years, relentlessly;
Can someone please direct me to where I can cash in the carbon credits?
You assistance in this matter is appreciated.
This sig is not paradoxical or ironic.
The text of the article makes reference to "misconceptions regarding cooling" that were driven by "Northern Hemisphere effects up to 1970." The paper argues for Global Warming not Global Cooling, but there was enough of a buzz about Global Cooling back in the day that this paper gives it mention.
So there.
However, Figure 6 does not predict that all of that rise will occur prior to 1998, with a flat-to-falling trend since then.
Ah, 1998. The obvious choice for picking as the specific year to measure all warming against. Due to its magical properties of being a special goalpost, we can ignore the yearly variation that would normally necessitate a rolling average and shows temperatures rising unabated well into this decade. Instead we can simply compare temperatures to 1998 and 1998 only, because it's magic, and say the warming has stopped.
How fortunate that it was not actually 1999, or 1996, that were the magical goalposts! Then we'd be forced to conclude that the warming has accelerated after the change to the new post-magic-year epoch! Soon the earth will be cooked!
But nope, since we measure from 1998, and not 1999, and certainly not with valid statistical methods, we say any predictions of warming in the 1st decade of the 21st century were wrong.
Phew! What a relief!
The enemies of Democracy are
You are leaping to the conclusion that anyone in the stop-climate-change mainstream (as opposed to the fringe) desires or intends to trash the economy. That's really rude, since it assumes either horrible motives or absurd stupidity on the part of people proposing these things.
One of the reasons for a proposal like carbon tax or carbon cap-and-trade is that those address exactly the problem (GHG emissions) without pre-supposing a solution. It's up to the market to allocate resources in the best way to avoid those carbon-associated costs.
Second, people have studied what it would take. Our big-ticket GHG items are (personal) transportation, the mammal-meat production stream (everything from fertilizer to grow corn, to burping cattle, to manure "lagoon" emissions), and electricity generation. It does not destroy the economy to eat less meat (the money we save, we spend on something else). It does not destroy the economy to drive smaller cars, carpool, ride bicycles, and/or telecommute and use mass transit. Electricity generation is the hardest problem, principally because non-FF sources will require larger distribution networks, storage, and some amount of "smart loads", and none of that is in place right now (you could cut your beef consumption in half tomorrow, and if people were motivated, they could start carpooling in short order). On the demand side we can do everything from painting roofs white, to better insulating refrigerators, to sealing air leaks in our houses. These things do not destroy the economy.
...how many nuclear plants we could have built in 30 years. Too bad Hansen didn't start advocating for nuclear power instead of more government power.
When Fascism comes to America, it will call itself Anti-Fascism, and tell you to give up your guns.
Truly, a stunning, witty and convincing argument on your part. Hardly scientific, but amusing :)
If I can take it that you're willing to stipulate that "Catastrophic" is non-falsifiable, and that even if there is significant anthropogenic global warming in play, that it will be either benign or neutral, or merely slightly bad, then maybe we don't disagree all that much after all.
But, will you agree that Hansen believes that anthropogenic global warming is going to be catastrophic?
So you're going to leap from basic thermodynamics, to a bold assertion that CO2 greenhouse effects get magically amplified by H2O greenhouse effects?
What observations would falsify that for you? Perhaps stable H2O levels, with increasing CO2 levels?
http://wattsupwiththat.com/2012/02/08/support-for-the-saturated-greenhouse-effect-leaves-the-likelihood-of-agw-tipping-points-in-the-cold/
Within 1% of the historical temperature record from 40,000BC to 2000AD. We're told GCMs can't predict 3 years, or 5 years out, but are supernaturally accurate at 100 years or more. Prove it by accurately forecasting 42,0000 years worth of temperature with your GCM.
How do you distinguish two 50 year periods, with indistinguishable *outcomes*, to two very separate *causes* (nature, vs. human CO2)?
What is your falsifiable hypothesis to exclude natural climate change?
Are you kidding me? You think we've actually got a lock on *every* single natural source and sink of heat?
Have you even read the IPCC statement on clouds?
http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch1s1-5-2.html
"the amplitude and even the sign of cloud feedbacks was noted in the TAR as highly uncertain"
You can't possibly expect me to believe that you've observed every factor of natural variation both in the modern era, and in the historical era. Try again :)
...is based on empirical evidence. and is multi-level.
In the summer, it will get hotter. That's irrefutable
Between ice ages, it will get hotter. Also irrefutable
Go ahead prove me wrong!
If I can take it that you're willing to stipulate that "Catastrophic" is non-falsifiable,
That's a word that you keep inserting. It has nothing to do with the actual scientific predictions.
and that even if there is significant anthropogenic global warming in play, that it will be either benign or neutral, or merely slightly bad,
I don't agree with that. Or at least, I don't agree that this is more likely than the alternative. Of course, all those words are subjective as well and therefore I'm interpreting them as I choose. And the significance of impacts is completely beside the climate science we're discussing, anyway.
So you're going to leap from basic thermodynamics, to a bold assertion that CO2 greenhouse effects get magically amplified by H2O greenhouse effects?
Where's the magic?
Which basic scientific fact do you disagree with?
1. Increased temperature increases the evaporation-precipitation balance of an air-water system, and therefore the water vapor content of the atmosphere.
2. Water vapor is a greenhouse gas.
What observations would falsify that for you? Perhaps stable H2O levels, with increasing CO2 levels?
The paper does not indicate stable global, vertically integrated (throughout the atmospheric column) H20 levels, which are in fact increasing (see papers by Soden, Dessler, Santer, etc.) That paper considers only 2% of the Earth's surface and only looks at surface humidity, whereas the bulk of the water vapor increase is predicted (and observed) to reside higher in the troposphere. Gee, some people might call that "cherry picking".
Hell, even Miskolczi points out that this paper doesn't say anything about the global average H20 column amount (see the link in the WUWT post). Didn't read that far when you were trolling for references to support your preconceived opinion, did you?
If only you spent a fraction of your time surveying the actual scientific literature rather than getting all your "science" from mangled misinterpretations of pseudoskeptic bloggers. But hey, Anthony Watts says it disproves the water vapor feeback, so it must be true. No need to read any other papers, huh? Some "skepticism" on your part.
Within 1% of the historical temperature record from 40,000BC to 2000AD.
They're not going to be able to do that unless you give them the historical forcings to at least that accuracy, which we don't know. So that's a meaningless test of their skill. But as long as you're making up ridiculous hoops for them to jump through, why not ask them to predict the last 4 billion years to 0.00001% accuracy while you're at it?
We're told GCMs can't predict 3 years, or 5 years out,
They could do some of that if they were initialized with the current climate state, but the data assimilation methods necessary to do that on a global scale are still in their infancy.
but are supernaturally accurate at 100 years or more.
They're not "supernaturally accurate"; their predictions have error bars of about a degree on them, given a fixed forcing. And surely you know the difference between initial value and boundary value problems, don't you?
Prove it by accurately forecasting 42,0000 years worth of temperature with your GCM.
In order to prove that they can forecast warming 100 years to, say, 20% accuracy (about the IPCC range, assuming known forcings, etc.), they have to reproduce 40,000 years of climate to 1% accuracy (given highly uncertain forcings and, for that matter, climate)? Yeah, that's a reasonable requirement.
How do you distinguish two 50 year periods, with indistinguishable *outcomes*,
Who said they have indisinguishable outcomes? You keep posting your stupid "can you tell these time series apart" "test", which ignores everything else we know about the climate. We know spatial patterns, we know observables other than temperature, we know something about forcings, etc.
Have you ever bothered to read any paper on detection and attribution? Or do you just blindly believe whatever your blog masters tell you about climate science?
What is your falsifiable hypothesis to exclude natural climate change?
What are you talking about? Hypotheses don't exclude natural climate change (which is itself a hypothesis). Data does. I already mentioned some of the data sources that have been used to exclude natural climate change. (Well, not exclude it ... it's there ... it's just not of the right magnitude / timing / sign to explain the recent warming.)
Are you kidding me? You think we've actually got a lock on *every* single natural source and sink of heat?
Pretty much. There are, as I said, only a handful possibilities that can lead to significant radiative imbalance. It comes from space, it comes from the ocean, it comes from the atmosphere. It's not the ocean (ocean heat). It's not the Sun (solar variability, cosmic rays, etc.). It's not atmospheric constituents (aerosols, etc.). It's very likely not clouds (no mechanism for long-range variability, and no long-term trend in clouds over the satellite era), but the error bars on that are big enough that there's still a little wriggle room, assuming you can come up with a plausible and observably verified physical mechanism for long-term variability.
Either way, there's certainly a hell of a lot less support for that than there is for the greenhouse effect. So what is you scientific basis for ignoring all of this physics in favor of vague handwaving about unspecified natural variability without observational support? The null hypothesis is the greenhouse effect, not vague handwaving.
"the amplitude and even the sign of cloud feedbacks was noted in the TAR as highly uncertain"
You're confusing cloud feedbacks with natural variability. (Note that even negative cloud feedbacks still lead to warming in response to a greenhouse forcing.)
Should have previewed ...
If I can take it that you're willing to stipulate that "Catastrophic" is non-falsifiable,
That's a word that you keep inserting. It has nothing to do with the actual scientific predictions.
and that even if there is significant anthropogenic global warming in play, that it will be either benign or neutral, or merely slightly bad,
I don't agree with that. Or at least, I don't agree that this is more likely than the alternative. Of course, all those words are subjective as well and therefore I'm interpreting them as I choose. And the significance of impacts is completely beside the climate science we're discussing, anyway.
So you're going to leap from basic thermodynamics, to a bold assertion that CO2 greenhouse effects get magically amplified by H2O greenhouse effects?
Where's the magic?
Which basic scientific fact do you disagree with?
1. Increased temperature increases the evaporation-precipitation balance of an air-water system, and therefore the water vapor content of the atmosphere.
2. Water vapor is a greenhouse gas.
What observations would falsify that for you? Perhaps stable H2O levels, with increasing CO2 levels?
The paper does not indicate stable global, vertically integrated (throughout the atmospheric column) H2O levels, which are in fact increasing (see papers by Soden, Dessler, Santer, etc.) That paper considers only 2% of the Earth's surface and only looks at surface humidity, whereas the bulk of the water vapor increase is predicted (and observed) to reside higher in the troposphere. Gee, some people might call that "cherry picking".
Hell, even Miskolczi points out that this paper doesn't say anything about the global average H20 column amount (see the link in the WUWT post). Didn't read that far when you were trolling for references to support your preconceived opinion, did you?
If only you spent a fraction of your time surveying the actual scientific literature rather than getting all your "science" from mangled misinterpretations of pseudoskeptic bloggers. But hey, Anthony Watts says it disproves the water vapor feeback, so it must be true. No need to read any other papers, huh? Some "skepticism" on your part.
Within 1% of the historical temperature record from 40,000BC to 2000AD.
They're not going to be able to do that unless you give them the historical forcings to at least that accuracy, which we don't know. So that's a meaningless test of their skill. But as long as you're making up ridiculous hoops for them to jump through, why not ask them to predict the last 4 billion years to 0.00001% accuracy while you're at it?
We're told GCMs can't predict 3 years, or 5 years out,
They could do some of that if they were initialized with the current climate state, but the data assimilation methods necessary to do that on a global scale are still in their infancy.
but are supernaturally accurate at 100 years or more.
They're not "supernaturally accurate"; their predictions have error bars of about a degree on them, given a fixed forcing. And surely you know the difference between initial value and boundary value problems, don't you?
Prove it by accurately forecasting 42,0000 years worth of temperature with your GCM.
In order to prove that they can forecast warming 100 years to, say, 20% accuracy (about the IPCC range, assuming known forcings, etc.), they have to reproduce 40,000 years of climate to 1% accuracy (given highly uncertain forcings and, for that matter, climate)? Yeah, that's a reasonable requirement.
www.climatedepot.com
Brains. Use them.
You'd already know where to find them if you were qualified to make a serious comment on the topic.
And there's your problem - you're claiming certainty where you simply can't. When post-high human CO2 emissions warming is indistinguishable from pre-high human CO2 emissions warming, you're making assertions that simply cannot hold.
The null hypothesis is that all observed climate change in the 1900s was caused by the same mechanisms as all observed climate change before the 1900s. You can't just say "here's my CO2 model, and no other models work as well as it does" - that's arguing against straw men. What you need is a falsifiable hypothesis statement.
Wow. That's bold. You've just boiled down perhaps the most complicated system imaginable, and asserted that you've got a solid lock on every possible influence. How's this for a surprise for you:
http://hockeyschtick.blogspot.com/2012/04/new-paper-finds-climate-variation-due.html
Umm, no. The null hypothesis is natural climate change. Always has, always will. To show that you've got a model worth paying attention to, I'll assert you need the following - 1) a clear statement of what observations would falsify the basic conceit of your model (i.e., CO2 drives everything), and 2) a run of your model from say, 40,000BC to 2000AD, without arbitrary curve fitting, that is accurate to within 1% of observed data.
You're kidding me, right? Greenhouse forcing of butterfly breath leads to more heat, leads to more clouds, which happen to be of the heat reflecting type that makes the world cooler, and you're saying that this will make the world...warmer?
Really? So if all the human CO2 emissions ever made only caused, say, an additional 0.01C warming per century, that's perfectly acceptable for you? Either magnitude counts, or it doesn't. I'm perfectly willing to stipulate to AGW as in *any* nonzero positive impact on global average temperature, in the same way I'm willing to stipulate to BYBGW (back yard butterfly global warming).
In the world most simple model, that is correct. In reality, we observe significant differences. http://wattsupwiththat.com/2012/02/08/support-for-the-saturated-greenhouse-effect-leaves-the-likelihood-of-agw-tipping-points-in-the-cold/
"If a positive water vapor feedback response existed in the climate system, you’d expect both the specific and relative humidity to increase with time. It didn’t. This ends up putting the kibosh on the idea of tipping points, and a lack of positive water vapor feedback pretty much takes all the scare out of CO2 induced climate change."
Some great comments on that: http://wattsupwiththat.com/2009/12/16/nasa-says-airs-satellite-data-shows-positive-water-vapor-feedback/
"http://geotest.tamu.edu/userfiles/216/Dessler2008b.pdf than this is not worth a iota. Mesurements from 5 years is hardly something that would normally qualify as “climate”science. The results in the article are without any error analysis whatsoever and if you do one youre in for a surprise: http://landshape.org/enm/propagation-of-uncertainty-through-dessler/
“The confidence limits of the mean are then 1.96*3.16*0.37 or 2.29, giving a lower limits to the estimated 2.04 W/m2/K value of vapor feedback of -0.25 W/m2/K. Being less than zero, this indicates that zero feedback is within the limits of uncertainty.”
Dressler actually shows that there is room for a negative feedback, still."
Care to hang your hat on some other cherry trees? :)
So...long story short...they've got no idea what natural climate change looked like in the past, so they can't distinguish it in the present.
So, we've got data networks that are still in their infancy, by the science is settled? :) Nice.
If an astrologist had 20% accuracy, would that make astrology science? Show me your necessary and sufficient falsifiable hypothesis statement :)
And there's your problem - you're claiming certainty where you simply can't. When post-high human CO2 emissions warming is indistinguishable from pre-high human CO2 emissions warming,
Look, this is nonsense. If you can't understand that you can distinguish between scenarios by looking at causes as well as effects (and looking at more effects than a gross quantity like "global average surface temperature"), then you're just willfully ignoring evidence and are scientifically incompetent. I can't help you.
What you need is a falsifiable hypothesis statement.
You don't have a falsifiable hypothesis statement. "Natural variability" isn't even a hypothesis until you start specifying what it is. You're "not even wrong".
The null hypothesis is that all observed climate change in the 1900s was caused by the same mechanisms as all observed climate change before the 1900s.
Nope. That would be a stupid null hypothesis, because we know that there are non-natural effects that weren't present in the 1900s. The null hypothesis is relative to your scientific knowledge. Nobody's going to say that my null hypothesis is "the ball will hover if I let go of it". It's going to fall. Then you can argue about alternate hypotheses regarding how it's going to fall.
Wow. That's bold. You've just boiled down perhaps the most complicated system imaginable, and asserted that you've got a solid lock on every possible influence.
This isn't really that hard, you know. You're playing the "god of the gaps" here. "Sure, we've looked at all the places where heat can enter the atmosphere, but maybe there's some other place, like an extra dimensional portal!!"
To show that you've got a model worth paying attention to, I'll assert you need the following
I've already explained why this is a stupid test of climate models.
You're kidding me, right?
Nope. You're just showing you don't know what a "negative feedback" is.
Greenhouse forcing of butterfly breath leads to more heat, leads to more clouds, which happen to be of the heat reflecting type that makes the world cooler, and you're saying that this will make the world...warmer?
Yes, if it's what climatologists call a negative feedback. A negative feedback is a suppressing feedback, meaning you get less warming than you otherwise would, not cooling. That is, the cooling effect of clouds isn't greater than the total warming. Go ahead, look up some climate papers on linear feedback analysis and see how they define that term. (Oh gee, that would require you to read some real science instead of blog posts.)
The scenario you're describing is an unstable feedback, which don't really exist in nature.
P.S.
How's this for a surprise for you:
Again, totally irrelevant to the attribution question. It doesn't matter what causes ENSO when ENSO can't cause the recent warming (see ocean heat data again).
Really? So if all the human CO2 emissions ever made only caused, say, an additional 0.01C warming per century, that's perfectly acceptable for you?
I don't know what you're talking about. All my statements are predicated on the IPCC range of warming. Given that, whether the impacts are going to be "bad" or not is a subjective statement, about which I have my own opinions.
In the world most simple model, that is correct. In reality, we observe significant differences.
I've already explained what's wrong with that claim, so I don't know why you're still repeating it, other than your ideological biases.
Some great comments on that:
Even if I believe some blog's unpublished error analysis, that own analysis still strongly favors a positive water vapor feedback.
If you want to present evidence favoring a small water vapor feedback. go ahead.
So...long story short...they've got no idea what natural climate change looked like in the past, so they can't distinguish it in the present.
Don't be a fool. Just because they don't have natural forcings in the past doesn't mean they don't have them now.
So, we've got data networks that are still in their infancy, by the science is settled? :) Nice.
"Data networks" have nothing to do with it. It's how you use the data to initialize models that's the issue. Furthermore, the inability of models to be initialized only affects their short term predictions, which are obviously strongly initial value dependent, not the long term predictions, which are boundary value dependent. I already explained this.
If an astrologist had 20% accuracy, would that make astrology science? Show me your necessary and sufficient falsifiable hypothesis statement :)
I don't think you understand what a falsifiable hypothesis statement is. You haven't presented any yourself, despite ranting about null hypotheses.
The problem is, climate change is about power and control. Remove that, and, there is nothing there. The people that want power and control, will use any reason to obtain it. You can see this for yourself, be merely asking, what does this person want to happen. If it ends with a person with a gun forcibly stealing ones hard earned money by force, then you can know it is about power and control. If it were proven that the climate is fine, it wouldn't matter any, they would just pick a new thing to worry about to try and convince you, they _need_ to steal your money from you, and from every one else. Those that don't understand history, or what a totalitarian state wants, are doomed to repeat it. The notion that the temperature went up 1 degree or didn't, or up 50, doesn't matter, they _only_ want power and control, they don't care about the climate.
Nope, sorry, you are misinformed and full of shit.
You are leaping to the conclusion that anyone in the stop-climate-change mainstream (as opposed to the fringe) desires or intends to trash the economy. That's really rude, since it assumes either horrible motives or absurd stupidity on the part of people proposing these things.
Too bad. I find both present in many advocates of catastrophic AGW.
It does not destroy the economy to drive smaller cars, carpool, ride bicycles, and/or telecommute and use mass transit. Electricity generation is the hardest problem, principally because non-FF sources will require larger distribution networks, storage, and some amount of "smart loads", and none of that is in place right now (you could cut your beef consumption in half tomorrow, and if people were motivated, they could start carpooling in short order). On the demand side we can do everything from painting roofs white, to better insulating refrigerators, to sealing air leaks in our houses. These things do not destroy the economy.
This sort of statement places you solidly on the "absurd stupidity" side of the spectrum. Your argument for doing these things is that they won't "destroy the economy". Scrubbing Great Britain from the map with a death ray won't destroy the economy outside of the UK either. That doesn't make it a good idea.
When you telling people what to do, it both interferes with the economy (which is after all about trade and other value-changing decisions). Such things don't destroy the economy, but they do tend to destroy wealth by forcing people to make decisions that they didn't want to make. That drives people into poverty. There's also the matter of impinging on human freedom and empowering government bureaucracies.
Uh, seems the link in my previous post broke, so there's a link to the page containing it.
"First they came for the slanderers and i said nothing."
Ah, "absurd stupidity". I guess that's polite, if you're a fucking idiot.
In addition to being impolite, you are also unable to construct anything like a plausible justification that curtailing GHG emissions will do serious harm ("sacrifice", "at the cost of prosperity") to the economy. You start with an implausible hyperbolic analogy ("death ray", "Great Britain"). That's not proof. Next, you play innumerate hopscotch from "telling people what to do", to "interfere with the economy", to "destroy wealth", to "drives people into poverty". At every step, you fail to provide numbers, and fail to consider "compared to what", and whether there are any relevant examples that would support your argument. Lots of things "destroy wealth" -- to judge from recent unemployment reports, good weather creates wealth (employment), and bad weather destroys it. Underregulation of banks and mortgage lending appears to eventually destroy wealth, too, and it blew a bigger hole in our economy than anything else I can point to.
For an end-to-end test of your "theory", we might consider nations that are roughly as wealthy as ours, that have more regulations, and look at their poverty rates. If the poverty rate in Scandinavia or other Northern European countries (famous for regulations) is not higher than ours, then your argument falls to pieces. Let me check... (CIA world factbook, wikipedia, both caution that definition of poverty varies by country) -- it doesn't appear that they have a higher poverty rate. Austria, Switzerland, Denmark, all lower. Germany, 15.5% versus our 15% (but they're still digesting East Germany, aren't they?) Finland and Sweden have about the same unemployment rate as we do, Norway's is much lower, so it doesn't look like regulation is hurting them there. So I think there is no evidence for your claim; within limits, "telling people what to do" is not a poverty-creator. Note that you're also mischaracterizing the favored "solutions" for global warming, which are generally market-based (cap-and-trade and/or carbon tax), both because market-based solutions will tend to be more efficient (the market makes it so) and because that explicitly avoids "telling people what to do" -- if you want to burn carbon, and you can afford it, that can be your choice.
So it looks to me like you are making stuff up from libertarian religion, and that, only after constructing a strawman to attempt (AND FAIL) to knock down (that should be really embarrassing to you). Everything you say is accepted as gospel by libertarians, even if there is no particular data to support it (or even if there is data to contradict it, as there is in this case). Climate change poses a problem for libertarians, because if it is caused by humans, and if it is costly, then the only solution is government interference with the economy.
This is James Hansen, head of NASA's Goddard Institute for Space Studies, who has been awarded more honours for science than almost anyone else I can think of... and produced this report when very few scientists were even looking at climatology.
http://en.wikipedia.org/wiki/James_Hansen#Honors_and_awards
I'm by no means an expert on climate science but I do know enough to know that the denialists are full of it. In fact, the US seems to be the only place in the world denialism is an accepted position.
And even on a basic level, the greenhouse effect is as proven as any science. It really shouldn't be a surprise to anyone that if we pump CO2 into the atmosphere the planet will get warmer.
People are so busy high-fiving about this one "model"... but ignoring the larger problem: there really is no accepted accurate way of taking the Earth's temperature. After all where do you stick the thermometer? A review of the NASA surface stations has shown that most of them are installed incorrectly and yielding bad data.
http://www.surfacestations.org
Besides both of the climateGate scandals destroying his credibility, Hansen himself has been found to be altering the original temp datasets:
http://wattsupwiththat.com/2007/08/11/lights-out-guest-post-by-steve-mcintyre/
And his "outside activities" are a little sketchy, as well:
http://wattsupwiththat.com/2011/06/21/nasas-hansen-asked-to-account-for-outside-activities/
Not to mention that CO2 actually works as a coolant, and protects us from CMEs from the sun:
http://science.nasa.gov/science-news/science-at-nasa/2012/22mar_saber/
The only hard, uniform, observable, datasets we have are from NASA's Aquos satellite, and that hasn't shown any warming in 12 years. The fact is, we don't know what temperature it is. And we certainly don't need to start rolling back the industrial age to "save us". And what does Hansen scream that we "desperately need to do"? Reduce global CO2 from 390ppb to 350ppb. That's an 11% reduction. And since the entire human race's CO2 footprint is only 4% of the global total... he's asking for the total elimination of the human race, just for starters. Are any of you really going to get behind this weasel?
Sadly, you are wrong. There is a controversy about being related to monkeys that is divided along party lines. Thus, we can conclude that there is something wrong with the anti-science party.
Question 7: 5 points
What’s the best thing a person can do personally to cut greenhouse gas emissions?
A. Drive a hybrid car
B. Eat one less hamburger a week
C. Buy all your food from local sources
Question 8: 3 points
Which is most effective at stopping the greenhouse effect?
A. Public-awareness campaigns to discourage consumption
B. Cap-and-trade agreements on carbon emissions
C. Volcanic explosions
D. Planting lots of trees
http://www.amazon.com/Super-Freakonomics-Patriotic-Prostitutes-Insurance/dp/0060889578
Surprising and fascinating.
Not all websites are about things happening now. Wikipedia has a nice article on The Battle of Hastings, despite a distinct lack of internet in 1066.
If there were dozens of models by respected scientists in the 1970's, I suspect some of them would be mentioned somewher on the internet. Especially considering the controversial nature of the Global Warming issue, and the straw-grasping of the most rabid deniers.
... as cherry picking the data.
I gave it a quick look but I don't see the current plateau. Temps have not increased (if anything a slight decrease) in more than a decade. Maybe CO2 and in particular man made CO2 isn't the problem or causitive agent.
What's the point of being polite? I don't see you listening to a polite rebuttal.
You start with an implausible hyperbolic analogy ("death ray", "Great Britain"). That's not proof.
You are correct, the argument here is reducio ad absurdum. That is reducing your argument to its absurd extremes.
Next, you play innumerate hopscotch from "telling people what to do", to "interfere with the economy", to "destroy wealth", to "drives people into poverty".
What is there to say? Made up numbers don't help the argument especially when most of the scenario has yet to come about. What we know of other such attempts at broad regulation is that they've led to remarkable declines in manufacture in the developed world and similar increases in wealth in countries without such regulation.
We impose restrictions on peoples' choices and distortion of the economy for poorly defined and incredible reasons. Some people think that this time it will be different from all the other times such things were done to the detriment of human society. All I can say is that massive changes to human iinfrastructure should require solid evidence not the poorly tested speculation that passes for AGW projections.
If the poverty rate in Scandinavia or other Northern European countries (famous for regulations) is not higher than ours, then your argument falls to pieces. Let me check... (CIA world factbook, wikipedia, both caution that definition of poverty varies by country) -- it doesn't appear that they have a higher poverty rate. Austria, Switzerland, Denmark, all lower. Germany, 15.5% versus our 15% (but they're still digesting East Germany, aren't they?) Finland and Sweden have about the same unemployment rate as we do, Norway's is much lower, so it doesn't look like regulation is hurting them there.
It's worth noting here that the lesser countries of the EU are heavier regulated and they don't have those relatively nice rates.
So it looks to me like you are making stuff up from libertarian religion, and that, only after constructing a strawman to attempt (AND FAIL) to knock down (that should be really embarrassing to you). Everything you say is accepted as gospel by libertarians, even if there is no particular data to support it (or even if there is data to contradict it, as there is in this case). Climate change poses a problem for libertarians, because if it is caused by humans, and if it is costly, then the only solution is government interference with the economy.
It always puzzles me why there is such misunderstanding of libertarianism especially by people who advocate catastrophic AGW. Carbon taxes are not inimical to most flavors of libertarianism, just as they aren't palatable to a variety of environmentalists.
lol Thats correct. Rather than have a conversion on WHY we can't predict the weather for 3 days let alone decades, just make personal attacks. Climate science doesn't have much data to go on, of course I still support their work. I don't think its mature enough yet to be useful to determine if its the sun or industrialization thats making the planet .3 degrees warmer over a ten year period or whatever the results seem to be this month.
If no one is willing to say anything and at least argue a few points, then we just have dumb ideas be popular opinion for decades. Gore still has multiple houses, and flies in jets. I don't see him acting like mother Teresa over global climate change. I don't even see him donating most of his own money toward it.
Anyone afraid of stock market change, political change, income change..etc? If people are afraid of change, then they are afraid of everything.
You are given two sets of observations (effects). Both for fifty years, both showing similar warming trends.
You are now trying to say that the same effect has two *different* causes. By what methodology are you discerning separate causes, without seeing a difference in effect? Be specific.
Natural variability is the null hypothesis. You can exclude the null hypothesis, but you cannot strictly falsify it.
Your problem is that you've got a non-falsifiable hypothesis statement, *and* you can't exclude the null hypothesis.
First off, I think you mean "non-natural activity" (the actual temperature would be an effect). But even if we know that there are non-natural activities post-1950 of significant magnitude, that gives us no reason to believe that they *caused* any measurable *effects*. That is supposition. The burden you carry is to be specific about what observations would exclude the null hypothesis of natural climate change, and what observations would falsify your favored conceit of human CO2 induced climate change.
The lady doth protest too much :) The "god of the gaps" argument is the one *you're* relying on, asserting that without a competing hypothesis, filling in all the gaps, that your central conceit of human CO2 induced climate change must be true. :)
But it wasn't a very good explanation, was it? :)
A negative feedback applies pressure towards an equilibrium point. It is perfectly possible (and often the case) that negative feedback will cause oscillations around the point of stability. This means that you will get both cooling and warming effects from negative feedback, not just "less warming". Try again!
You don't think ocean temperatures can cause warming?
http://woodfortrees.org/plot/hadsst2gl/from:1998/to:2012/plot/hadcrut3vgl/from:1998/to:2012
Really?
And what would the lower bound of that be for you, in degrees C per century? Be specific.
Your explanation wasn't a very good one. :)
So what observations, past present or future, would you accept as a falsification of the idea of a specific magnitude of positive water feedback driven by CO2? Be specific.
So say you've got a measure of some natural forcings since the beginning of the satellite age...do you really think we've had enough time and resolution of data to truly exclude the null hypothesis of natural climate change?
Long term predictions of a stochastic system like our climate aren't boundary value dependent - they are obviously strongly *immediate* valued dependent. And this is why none of your GCMs would be able to take *any* set of initial conditions from 40,000BC and come up with anything *near* a realistic prediction, even smoothed at 1000 year levels.
I'm not presenting a competing falsifiable hypothesis, I'm arguing that you haven't proposed one, and you haven't excluded the null hypothesis of natural climate change. The burden of proof in science is on the affirmative - all I have to do is poke holes in your poor explanations :)
I didn't see polite, or a rebuttal, as noted in the other reply (which is evidence that I listened none-the-less). The "science" behind "cutting CO2 emissions will sacrifice-the-economy/destroy-wealth/increase-poverty" is not very strong. We've got far more data and better tested models (and better-predicting models) for the climate than we do for the economy. (This is partly because the economy is not just complex and chaotic, but filled with actors attempting to game the economy for an advantage as soon as they can figure out how it currently works. We can also work with thousands of years of preserved climate indicators, that we lack for economics.)
The "science" behind "cutting CO2 emissions will sacrifice-the-economy/destroy-wealth/increase-poverty" is not very strong. We've got far more data and better tested models (and better-predicting models) for the climate than we do for the economy.
The economic models behind that argument are stronger than the science. And most of the problem with catastrophic AGW is the economics. It's a common flaw I see that someone argues the whole argument on the strength of the most solid components (such as radiative models or number of climate papers published which validate some model of AGW) while downplaying the weakest parts of the argument (namely, whether corrective behavior is more harmful or beneficial than merely doing nothing).
I rather doubt that the economic models are that strong, and you have certainly not supported your claim. They're not based on physics, we don't have thousands of years of quite good economic data (tree rings, ice cores) or hundreds of thousands of years of not-too-bad data (sediment cores). They did not predict this slump that we're in now, and alleged economists are arguing (from the so-called "fresh" and "salt" water sides) whether the prescription to revive the economy is more government borrowing and spending (for those countries that control their currencies, i.e., not the southern EU) or more austerity. Lots of people predicted that Obama's stimulus package would spark hyperinflation, which has thus far failed to materialize -- were they using economic models? If the economic models are so good, why is there so much disagreement over the right action to take to get people back to work?
Business in the US has a long history of crying "wolf", and the groups that oppose action to reduce GHG emissions also opposed (for example) Clinton's tax increases, claiming that they would be very bad for the economy (quotes here: http://thinkprogress.org/economy/2010/08/10/173450/1993-quotes/ ). They were quite wrong in their prediction; why should I pay any attention to what they say now? Or were they making shit up then, but now, now, they are using reliable economic models?
OTOH, economic fixes are notorious for backfiring and creating perverse incentives. For example, Los Angelos county suddenly boots "desert rats" (at their expense no less) for violating laws that LA County hadn't cared about for decades. Turns out Obama's green energy loans were being used to buy property for solar power that was required by california renewable energy mandates.So it appears that thousands of people were being made homeless (at their expense unless the action is challenged successfully in the courts) for nebulous AGW reasons.
If AGW theorist produces evidence of model's predictions being accurate, then say "You can make those models say whatever you want them to say"
If not, then say "Those models can't even predict current conditions accurately."