All my statements are predicated on the IPCC range of warming.
And what would the lower bound of that be for you, in degrees C per century? Be specific.
I've already explained what's wrong with that claim, so I don't know why you're still repeating it
Your explanation wasn't a very good one.:)
that own analysis still strongly favors a positive water vapor feedback.
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.
Just because they don't have natural forcings in the past doesn't mean they don't have them now.
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?
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.
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 don't think you understand what a falsifiable hypothesis statement is. You haven't presented any yourself, despite ranting about null hypotheses.
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:)
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.
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.
You don't have a falsifiable hypothesis statement. "Natural variability" isn't even a hypothesis until you start specifying what it is.
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.
That would be a stupid null hypothesis, because we know that there are non-natural effects that weren't present in the 1900s.
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.
You're playing the "god of the gaps" here.
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.:)
I've already explained why this is a stupid test of climate models.
But it wasn't a very good explanation, was it?:)
A negative feedback is a suppressing feedback, meaning you get less warming than you otherwise would, not cooling.
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!
The one where you claimed that the surface humidity record over North America falsifies the water vapor feedback, when the water vapor feedback actually depends on the global water vapor content integrated over the entire atmospheric column.
It certainly falsifies it over North America, and so far you've got no data on the global water vapor content integrated over the entire atmospheric column.
Again, while we cannot say with certainty yet that this will apply to the rest of the globe, it certainly implies a local falsification that may very well be true on other spatio-temporal time scales.
in fact was contradicted by the very skeptic who WUWT claimed was supported by that paper
What was contradicted? I never made the claim that the north american observations were necessarily representative of the entire globe (just as the entire surface temperature network is hardly representative of the entire globe). That was your assumption, not my assertion:)
I'm not wasting my time replying to more of these obtuse posts.
You'd need to know more about the natural variability and the radiative forcings acting during that period.
Which, you've admitted, is completely unknown information. And yet, you blithely believe you can discern between natural climate change, and unnatural climate change:)
Seriously, is there *any* observational data that you wouldn't respond to with an ad hoc special pleading?:)
Gee, I don't know, which one of you posted a claim that was falsified in the very blog post that inspired it?
Talking about H2O vs. CO2 levels? Claiming it was a cherry pick is far from showing that it was falsified:)
The neat thing about cherry picks though, is that only one falsification is necessary to show a truly scientific hypothesis *wrong*. The burden of proof lies in the affirmative:)
And the significance of impacts is completely beside the climate science we're discussing, anyway.
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).
1. Increased temperature increases the evaporation-precipitation balance of an air-water system, and therefore the water vapor content of the atmosphere.
"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."
"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?:)
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...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.
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.
So, we've got data networks that are still in their infancy, by the science is settled?:) Nice.
In order to prove that they can forecast warming 100 years to, say, 20% accuracy (about the IPCC range, assuming known forcings, etc.),
If an astrologist had 20% accuracy, would that make astrology science? Show me your necessary and sufficient falsifiable hypothesis statement:)
(Well, not exclude it... it's there... it's just not of the right magnitude / timing / sign to explain the recent warming.)
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.
There are, as I said, only a handful possibilities that can lead to significant radiative imbalance.
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:
The null hypothesis is the greenhouse effect, not vague handwaving.
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.
Note that even negative cloud feedbacks still lead to warming in response to a greenhouse forcing.
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?
Once again, how this relates to climatology has been explained over and over to you.
You keep saying you've explained something. You keep forgetting that doesn't mean you've explained it correctly, or explained it well:)
you are an intellectually bankrupt dishonest liar. And you know it.
So, let's take that hypothesis, and counter it with its opposite, that in fact *you* are the intellectually bankrupt dishonest liar. How would one use the scientific method, and falsifiability, to determine which one of us is "intellectually bankrupt", and which one is actually doing science?
Go ahead, take your time, I know you can figure it out if you try:)
(And that sir, is an insult only if you want it to be:) )
I'll repeat my question again, and give you another chance to answer:
How hard have you tried to prove Catastrophic Anthropogenic Global Warming *wrong*? How hard has Hansen tried?:)
"the amplitude and even the sign of cloud feedbacks was noted in the TAR as highly uncertain"
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.
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:)
Truly, a stunning, witty and convincing argument on your part. Hardly scientific, but amusing:)
"Catastrophic" is a non-falsifiable statement. I thought you were scientific?
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?
No reason to believe that, other than basic thermodynamics and observations of the water vapor content of the atmosphere.
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?
Get to within 1% of what? And why is arbitrary request this a relevant test of anything?
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.
Well, long-term trend lines headed towards lessening CO2 concentrations and lower average temperatures over a span of decades would be welcome evidence contrary to global-warming theories.
Why would that be contrary? If you believe global average CO2 drives global average temperature (overwhelming all other natural signals), then a lowering CO2 *and* a lowering average temperature would be expected.
But if you were to address the central conceit of CO2 driving warming, would you accept it as falsified if say, we saw in the historical record of some ice core rising CO2 for 50 years, but falling temperatures?
Science is the proposition of a falsifiable hypothesis, the ruthless attempt to find those falsifications, and the *failure* to do so after concerted effort.
"Science is ultimately about establishing cause and effect. It’s not about guessing. You come up with a hypothesis — force x causes observation y — and then you do your best to prove that it’s wrong. If you can’t, you tentatively accept the possibility that your hypothesis was right. Peter Medawar, the Nobel Laureate immunologist, described this proving-it’s-wrong step as the ”the critical or rectifying episode in scientific reasoning.” Here’s Karl Popper saying the same thing: “The method of science is the method of bold conjectures and ingenious and severe attempts to refute them.” The bold conjectures, the hypotheses, making the observations that lead to your conjectures that’s the easy part. The critical or rectifying episode, which is to say, the ingenious and severe attempts to refute your conjectures, is the hard part. Anyone can make a bold conjecture. (Here’s one: space aliens cause heart disease.) Making the observations and crafting them into a hypothesis is easy. Testing them ingeniously and severely to see if they’re right is the rest of the job — say 99 percent of the job of doing science, of being a scientist."
How hard have you tried to prove Catastrophic Anthropogenic Global Warming *wrong*? How hard has Hansen tried?:)
3) Hansen's climate model was right but his emissions projections were wrong.
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.
4) The model was "wrong", in the sense of having a climate sensitivity different from the real world...This observation cannot "invalidate the central conceit" (i.e., falsify the greenhouse effect)
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.
5) You're an idiot, given all your moronic blathering in this threads about how modern climate change is indistinguishable from natural variation.
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.
In order to get my trust on a science issue, someone needs to start the scientific method with a clearly necessary and sufficient falsifiable hypothesis statement. Care to cite one?:)
I'm asking for something different, qmaqdk -> observations "consistent with" are all fine and dandy, but can you specify any observations that would *not* be "consistent with"?
The central conceit here is that human CO2 emissions are causing increases in global average temperature that overwhelm all natural drivers (and furthermore that such increase in global average temperature will be catastrophic). What observations can you specify that would falsify that central conceit?
Of course Climate change is a fact, and that humans are the primary instigators is also a fact.
Well, you're half right:)
Natural climate change is a fact. Given that climate has always changed, long before significant human CO2 emissions (or even significant humans existed), we can all stipulate to that.
Now, taking the bold step of asserting that humans are the primary driver of global average temperature (much less that an increase in global average temperature is bad), is a much larger speculation. But, if we're going to speculate, let's ask the question - what observations would convince you that your central conceit (humans are the primary instigators of climate change since say, 1950, whereas before climate change was natural) was wrong?
Here are two 50 year periods of the climate record. One comes from a time of low CO2 emissions. The other comes from a time with high CO2 emissions. Can you discern which one is which?
Interesting anecdote. However, I wonder, what observations would convince you that your basic premise is wrong, and that global average temperature changes over the past 100 years have been 1) within the bounds of natural variation, 2) not particularly harmful to the world or even impactful on regional weather patterns?
Does your point of view include the possibility of being wrong?
...come from astrologists as well. This doesn't make it science.
The fact of the matter is that *anyone* could have predicted the gentle rise in temperatures due to the natural end of the Little Ice Age. And if you'll take careful note, Hansen's graph doesn't start inflecting in any meaningful way until past 2020:)
The open question to those that believe in Catastrophic Anthropogenic Global Warming, is what observations would falsify the *central conceit*, not just the happenstance of natural climate change. What will require throwing away the "co2 drives warming" model, instead of just tweaking it to curve fit observations? 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.
Falsification means that the *reaction* to data can include admitting the central conceit is wrong. It doesn't mean that observations are "consistent with" prior predictions.
Which part of "None of the projections of climate science include what I would characterize as "catastrophic" global warming." did you fail to understand?
Well, wait a sec, color me corrected - if you truly believe that the state of the art climate science does not project any sort of catastrophe due to human contributions to global average temperature, and that business as usual, or even increased CO2 emissions aren't anything to worry about, then maybe you're just a lukewarmer like me:)
Coming up with excuses for not doing the math to check his ideas is the mark of a crank, not a scientist.
And you don't quite see that when you ask for a competing model before you're willing to accept the flaws in your own, that you're also making excuses?
When there is "natural" climate change, there is other evidence of a change in "natural" mechanisms--a change in solar radiance, for example.
You're making the bold assumption that we can and do observe all changes in the universe that have an effect on climate. Natural climate change can happen without you knowing its specific origin. In fact, right now, outside your window, the temperature is changing, but you can't tell if it's because some nearby plant is blocking a breeze, or if it's because heat is radiating out of your house, or if the humidity is changing due to some desiccant in your general vicinity.
The real world is not a laboratory, where everything that can be measured is measured, and complex systems can be decomposed into discrete parts for direct analysis. And to that point, you obviously have failed to find five (or even one) period of historical warming, in the past 100,000 years, similar to the past 50 years, but explained in detail via other mechanisms.
So nitpicking somebody else's model does not make your model right.
Exactly. Your model of CO2 isn't right simply because you'd like to nitpick straw-men models that don't yet exist.
No model is perfect; you have to show that their model is wrong in a way that matters. How do you do that?
You do that by having a model that is falsifiable, not one that responds to divergence from reality with ad hoc special pleadings. Astrology is a model. We know it is unfalsifiable. That is wrong in a way that matters.
Ah, typo. 0.1C/decade for the past century, probably a bit less.:)
And no La Nina cooling event, regardless of strength, has reduced the temp anomaly below zero or even 0.1C since 1976.
So, are you saying that in 1975, there was a La Nina cooling event that did reduce the temp anomaly below zero? You make it seem like 1976 was before the age of high CO2 emissions:)
And more importantly, this implies....what? We're rebounding out of a mini-ice age, we should *expect* temperatures to be on the rise. La Nina and El Nino, and other ocean oscillations, are major drivers of both global average temperature, and more importantly, regional climate effects (nobody ever experiences global average temperature, but regional climate effects are directly experienced).
"Thousands of blog readers are aware that the “similar findingswithout tree-ring data” were obtained only by including upside-down contaminated data. It’s disquieting that IPCC coauthors are unaware of this. The failure of Mann and his coauthors to retract or correct the PNAS 2008 article lingers on."
While the events in the ice cores indicate there's still much to be learned that doesn't mean that we are somehow not at all responsible for the last century.
Here are two 50 year periods of the climate record. One comes from a time of low CO2 emissions. The other comes from a time with high CO2 emissions. Can you discern which one is which?
Fiddling with the cloud feedback also does not eliminate the prediction of serious global warming that is likely to cause financial and human costs that far exceed the cost of mitigation.
Cite some numbers here - if we continue at 0.1C/century warming, why should we assume any sort of catastrophe? Did the world become more catastrophic over the past 100 years where we've experienced that?
So in your mind, there are no physical mechanisms responsible for "natural" climate change that could be studied and mathematically modeled.
Oh, certainly there are physical mechanisms for natural climate change, but I don't have to model them in order for them to be true. The simply *are*. Did electricity exist before we modeled it? Did chemistry exist before we modeled it? Did plate tectonics exist before we modeled it?
Of course it did. And so does natural climate change. Surely you don't deny that, do you?
So if somebody tells me that they believe that the modern warming is due to something other than CO2 ("cloud feedback" for example) and I ask them, "Have you checked your work mathematically? Is your theory consistent with known data?"
Sure we've checked it mathematically - we've got indistinguishable periods of 50 years of warming, one of which is asserted to be "natural" and the other asserted to be due to human CO2. There is no discernible difference, ergo, we have no strong assertion that the 50 year period we'd like to assert as due to human CO2 was anything but the natural course of events. Since things aren't unprecedented, there's no reason to assume that suddenly things happened in the same way for different reasons.
I'd be more convinced if you'd checked your work, and shown mathematically that it was possible to develop a physical model in which CO2 is not a strong climate driver, without losing consistency with the known climate data.
Again, you seem to believe that a flawed, falsified model must be believed in the absence of another mathematical model. This isn't how science works - you don't need to prove something else right in order to prove a hypothesis wrong. I'd be more convinced if the known climate data of the modern CO2 emitting era was unique in the historical climate record - but it isn't.
The sun rises and sets because of the rotation of the earth. But now you want me to believe that the sun rise of April 2, 2012 actually had a different cause? Color me skeptical:)
So first we have a straw man--no scientist has claimed that modern temperature records are unprecedented, only that the natural causes that have produced high temperatures in the past are not present today.
Okay, so let's take this slowly - you agree that modern temperature records aren't unprecedented, and that from a trivial examination of the past climate, we can see this has happened before.
Convince me. Find five periods of historical temperature change within say, the past 100,000 years, that match the historical temperature changes we've observed over the past 50 years. Now explain exactly all the natural factors that caused those past five periods of variation, and compare to the past 50 years.
Go!
When examined over the period of time that statistical analysis indicates is necessary to be able to reliably detect the trend expected from global warming, it is highly significant.
I'll argue that the period of time necessary is 100,000 years. How many years do you want to assert? 5? 10? Maybe 18 years?
So a single cold year would expose Hansen as conceited but 3.5 decades of progressive warming
Show me that we've never had 3.5 decades of progressive warming, and maybe you'd have something:) As it stands, you continue to carve loopholes so large in your favored predictions that there are no observations that would falsify your central conceit. This is the hallmark of religion.
isn't the burden of proof on YOU rather than spending 15 years telling everyone else they're wrong?
Interesting. You'll critique Christy for failing to meet some burden of proof, but you'll gladly and blithely assume that Mann and Hansen, et. al. are correct without any sort of proof:)
Nice:)
You might be putting too much faith in stabilising feedbacks as the ice-core records show about a dozen rapid shifts in average temps, on the order of 5 deg C, in only a couple of years,
Funny, that kind of rapid shift, in the absence of humanity, means that it's quite impossible to assert the mild.1C/century warming we've seen in the past 100 years is anything but business as usual for the planet:)
Slashdot Mirror
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 :)
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?
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!
It certainly falsifies it over North America, and so far you've got no data on the global water vapor content integrated over the entire atmospheric column.
Again, while we cannot say with certainty yet that this will apply to the rest of the globe, it certainly implies a local falsification that may very well be true on other spatio-temporal time scales.
What was contradicted? I never made the claim that the north american observations were necessarily representative of the entire globe (just as the entire surface temperature network is hardly representative of the entire globe). That was your assumption, not my assertion :)
I'll miss you!
Which, you've admitted, is completely unknown information. And yet, you blithely believe you can discern between natural climate change, and unnatural climate change :)
Seriously, is there *any* observational data that you wouldn't respond to with an ad hoc special pleading? :)
Talking about H2O vs. CO2 levels? Claiming it was a cherry pick is far from showing that it was falsified :)
The neat thing about cherry picks though, is that only one falsification is necessary to show a truly scientific hypothesis *wrong*. The burden of proof lies in the affirmative :)
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, 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?
You keep saying you've explained something. You keep forgetting that doesn't mean you've explained it correctly, or explained it well :)
So, let's take that hypothesis, and counter it with its opposite, that in fact *you* are the intellectually bankrupt dishonest liar. How would one use the scientific method, and falsifiability, to determine which one of us is "intellectually bankrupt", and which one is actually doing science?
Go ahead, take your time, I know you can figure it out if you try :)
(And that sir, is an insult only if you want it to be :) )
I'll repeat my question again, and give you another chance to answer:
How hard have you tried to prove Catastrophic Anthropogenic Global Warming *wrong*? How hard has Hansen tried? :)
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 :)
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.
Why would that be contrary? If you believe global average CO2 drives global average temperature (overwhelming all other natural signals), then a lowering CO2 *and* a lowering average temperature would be expected.
But if you were to address the central conceit of CO2 driving warming, would you accept it as falsified if say, we saw in the historical record of some ice core rising CO2 for 50 years, but falling temperatures?
Science is the proposition of a falsifiable hypothesis, the ruthless attempt to find those falsifications, and the *failure* to do so after concerted effort.
http://garytaubes.com/2012/03/science-pseudoscience-nutritional-epidemiology-and-meat/
"Science is ultimately about establishing cause and effect. It’s not about guessing. You come up with a hypothesis — force x causes observation y — and then you do your best to prove that it’s wrong. If you can’t, you tentatively accept the possibility that your hypothesis was right. Peter Medawar, the Nobel Laureate immunologist, described this proving-it’s-wrong step as the ”the critical or rectifying episode in scientific reasoning.” Here’s Karl Popper saying the same thing: “The method of science is the method of bold conjectures and ingenious and severe attempts to refute them.” The bold conjectures, the hypotheses, making the observations that lead to your conjectures that’s the easy part. The critical or rectifying episode, which is to say, the ingenious and severe attempts to refute your conjectures, is the hard part. Anyone can make a bold conjecture. (Here’s one: space aliens cause heart disease.) Making the observations and crafting them into a hypothesis is easy. Testing them ingeniously and severely to see if they’re right is the rest of the job — say 99 percent of the job of doing science, of being a scientist."
How hard have you tried to prove Catastrophic Anthropogenic Global Warming *wrong*? How hard has Hansen tried? :)
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.
In order to get my trust on a science issue, someone needs to start the scientific method with a clearly necessary and sufficient falsifiable hypothesis statement. Care to cite one? :)
I'm asking for something different, qmaqdk -> observations "consistent with" are all fine and dandy, but can you specify any observations that would *not* be "consistent with"?
The central conceit here is that human CO2 emissions are causing increases in global average temperature that overwhelm all natural drivers (and furthermore that such increase in global average temperature will be catastrophic). What observations can you specify that would falsify that central conceit?
Mod parent up. This "heads I win, tails you lose" mentality essentially means that a swath of predictions, +/- 30%, means "see, I'm right!"
Well, you're half right :)
Natural climate change is a fact. Given that climate has always changed, long before significant human CO2 emissions (or even significant humans existed), we can all stipulate to that.
Now, taking the bold step of asserting that humans are the primary driver of global average temperature (much less that an increase in global average temperature is bad), is a much larger speculation. But, if we're going to speculate, let's ask the question - what observations would convince you that your central conceit (humans are the primary instigators of climate change since say, 1950, whereas before climate change was natural) was wrong?
Here are two 50 year periods of the climate record. One comes from a time of low CO2 emissions. The other comes from a time with high CO2 emissions. Can you discern which one is which?
http://climate-skeptic.typepad.com/photos/uncategorized/2008/08/26/periodb.gif
http://climate-skeptic.typepad.com/photos/uncategorized/2008/08/26/perioda_3.gif
Interesting anecdote. However, I wonder, what observations would convince you that your basic premise is wrong, and that global average temperature changes over the past 100 years have been 1) within the bounds of natural variation, 2) not particularly harmful to the world or even impactful on regional weather patterns?
Does your point of view include the possibility of being wrong?
...come from astrologists as well. This doesn't make it science.
The fact of the matter is that *anyone* could have predicted the gentle rise in temperatures due to the natural end of the Little Ice Age. And if you'll take careful note, Hansen's graph doesn't start inflecting in any meaningful way until past 2020 :)
The open question to those that believe in Catastrophic Anthropogenic Global Warming, is what observations would falsify the *central conceit*, not just the happenstance of natural climate change. What will require throwing away the "co2 drives warming" model, instead of just tweaking it to curve fit observations? 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.
Falsification means that the *reaction* to data can include admitting the central conceit is wrong. It doesn't mean that observations are "consistent with" prior predictions.
Well, wait a sec, color me corrected - if you truly believe that the state of the art climate science does not project any sort of catastrophe due to human contributions to global average temperature, and that business as usual, or even increased CO2 emissions aren't anything to worry about, then maybe you're just a lukewarmer like me :)
And you don't quite see that when you ask for a competing model before you're willing to accept the flaws in your own, that you're also making excuses?
You're making the bold assumption that we can and do observe all changes in the universe that have an effect on climate. Natural climate change can happen without you knowing its specific origin. In fact, right now, outside your window, the temperature is changing, but you can't tell if it's because some nearby plant is blocking a breeze, or if it's because heat is radiating out of your house, or if the humidity is changing due to some desiccant in your general vicinity.
The real world is not a laboratory, where everything that can be measured is measured, and complex systems can be decomposed into discrete parts for direct analysis. And to that point, you obviously have failed to find five (or even one) period of historical warming, in the past 100,000 years, similar to the past 50 years, but explained in detail via other mechanisms.
Exactly. Your model of CO2 isn't right simply because you'd like to nitpick straw-men models that don't yet exist.
You do that by having a model that is falsifiable, not one that responds to divergence from reality with ad hoc special pleadings. Astrology is a model. We know it is unfalsifiable. That is wrong in a way that matters.
Ah, typo. 0.1C/decade for the past century, probably a bit less. :)
So, are you saying that in 1975, there was a La Nina cooling event that did reduce the temp anomaly below zero? You make it seem like 1976 was before the age of high CO2 emissions :)
And more importantly, this implies....what? We're rebounding out of a mini-ice age, we should *expect* temperatures to be on the rise. La Nina and El Nino, and other ocean oscillations, are major drivers of both global average temperature, and more importantly, regional climate effects (nobody ever experiences global average temperature, but regional climate effects are directly experienced).
Endured? Mann's work was thoroughly refuted, and Hansen's either has error bars so big you can predict *anything*, or has also been refuted :)
http://climateaudit.org/2011/12/13/ar5-and-mikes-pnas-trick/
"Thousands of blog readers are aware that the “similar findingswithout tree-ring data” were obtained only by including upside-down contaminated data. It’s disquieting that IPCC coauthors are unaware of this. The failure of Mann and his coauthors to retract or correct the PNAS 2008 article lingers on."
Here are two 50 year periods of the climate record. One comes from a time of low CO2 emissions. The other comes from a time with high CO2 emissions. Can you discern which one is which?
http://climate-skeptic.typepad.com/photos/uncategorized/2008/08/26/periodb.gif
http://climate-skeptic.typepad.com/photos/uncategorized/2008/08/26/perioda_3.gif
Cite some numbers here - if we continue at 0.1C/century warming, why should we assume any sort of catastrophe? Did the world become more catastrophic over the past 100 years where we've experienced that?
Oh, certainly there are physical mechanisms for natural climate change, but I don't have to model them in order for them to be true. The simply *are*. Did electricity exist before we modeled it? Did chemistry exist before we modeled it? Did plate tectonics exist before we modeled it?
Of course it did. And so does natural climate change. Surely you don't deny that, do you?
Sure we've checked it mathematically - we've got indistinguishable periods of 50 years of warming, one of which is asserted to be "natural" and the other asserted to be due to human CO2. There is no discernible difference, ergo, we have no strong assertion that the 50 year period we'd like to assert as due to human CO2 was anything but the natural course of events. Since things aren't unprecedented, there's no reason to assume that suddenly things happened in the same way for different reasons.
Again, you seem to believe that a flawed, falsified model must be believed in the absence of another mathematical model. This isn't how science works - you don't need to prove something else right in order to prove a hypothesis wrong. I'd be more convinced if the known climate data of the modern CO2 emitting era was unique in the historical climate record - but it isn't.
The sun rises and sets because of the rotation of the earth. But now you want me to believe that the sun rise of April 2, 2012 actually had a different cause? Color me skeptical :)
Okay, so let's take this slowly - you agree that modern temperature records aren't unprecedented, and that from a trivial examination of the past climate, we can see this has happened before.
Convince me. Find five periods of historical temperature change within say, the past 100,000 years, that match the historical temperature changes we've observed over the past 50 years. Now explain exactly all the natural factors that caused those past five periods of variation, and compare to the past 50 years.
Go!
I'll argue that the period of time necessary is 100,000 years. How many years do you want to assert? 5? 10? Maybe 18 years?
http://woodfortrees.org/plot/hadcrut3vgl/from:1998/to:2012/plot/hadcrut3vgl/from:1998/to:2012/trend/plot/esrl-co2/from:1998/to:2012/normalise
Show me that we've never had 3.5 decades of progressive warming, and maybe you'd have something :) As it stands, you continue to carve loopholes so large in your favored predictions that there are no observations that would falsify your central conceit. This is the hallmark of religion.
Interesting. You'll critique Christy for failing to meet some burden of proof, but you'll gladly and blithely assume that Mann and Hansen, et. al. are correct without any sort of proof :)
Nice :)
Funny, that kind of rapid shift, in the absence of humanity, means that it's quite impossible to assert the mild .1C/century warming we've seen in the past 100 years is anything but business as usual for the planet :)