Measure spectral radiance emitted to space (for the spectrum that you are interested in). Subtract that from the black body radiance. Spectral radiance is measured in Wm^-2. This was in the very first post. Thanks for paying attention.
So let's be very clear here - you're measuring spectral radiance for the spectrum that you're interested in. After that, you're using a model to decide what forcing is.
So what you have is a spectral-radiance-o-mometer, not a forcing-o-mometer. You've got a model which derives a theoretical forcing from your spectral-radiance-o-mometer.
Understand your error now?:)
Except that apples are not a forcing you idiot.
What, you're asserting that apples and plants are a feedback for global cooling? Really?
Or are you going to make the bold assertion that apples and other plants have no effect on climate at all?
It's in the very first post. Thanks for paying attention.
Fail - you've taken disparate falsifiable hypotheses, and simply asserted that they combine in some unspecified way to show AGW. Each link in the chain is subject to strict scrutiny in order for the chain to hold together:)
However to be a hypothesis it has to be falsifiable. Your "it's natural" isn't falsifiable.
Let's revisit your proposed null hypothesis:
"My hypothesis would be that each change of climate had a cause."
Explain how that hypothesis is any more falsifiable than "each change of climate had a natural cause". Demonstrate how you could observe a change of climate without any cause, natural or unnatural.
"It's natural" is a perfectly valid null hypothesis, because it states clearly that the beginning of our knowledge is an empty set. We don't have to rely on "it was aliens" or "it was leprechauns" or "it was humans" or "it was god" - without any specifically defined cause, we know that left to its own devices, climate and weather have changed without humanity or any other intelligent or sentient power causing things to happen.
Fact: AGW is falsifiable because it makes empirically testable predictions. FULL STOP. We can get to the rest when we agree on that.
I believe you mean (A)AGW, but correct me if you for some reason think I've misinterpreted your meaning, and you *intended* to leave that out as an important caveat. When you say "I am saying that AGW is *technically* falsifiable", that sounds like a yes answer to "Simply that the net impact of humanity's CO2 is positive, no matter *how* small".
Put in your terms:
Fact: (A)AGW is falsifiable because it makes empirically testable predictions. It makes no claims as to the magnitude of warming due to CO2, only that it is at least infinitesimally positive. FULL STOP.
Not to prejudge your answer before you've had a chance to give it, I would imagine that disagreeing with that fact means that you believe that (A)AGW == AGW for all intents and purposes. If that's true, please explain why you would consider those two functionally equivalent.
Oops. You forgot again to answer my questions. Perhaps the idea of the questions isn't sitting well with your unconscious denial. Here they are again:
1) Are you simply supporting any *technically* true hypothesis of (A)AGW? Simply that the net impact of humanity's CO2 is positive, no matter *how* small?
A "yes" answer to that question, and I think we're both on the same page. A "no" answer on that question, and you'll have to help me understand your point of view more clearly.
2) Explain to me where in any recent established philosophy of science besides AGW (Popper or beyond), one actually does *not* make a falsifiable hypothesis? Can you give a specific example?
Or are you going to say that AGW _doesn't_ make predictions that can be falsified?
Your hypothesis of (A)AGW (any anthropogenic global warming) does make falsifiable predictions, but not very useful ones. You still haven't found a hypothesis of AGW with any sort of specific magnitude that can be falsified, although I invite you to do so.
Again, try to respond with your next post answers to my questions, and help bring more understanding to the conversation. I know they may not sit well in your mind, but take a while and try to overcome the difficulty you're having thinking about them!
If you removed all greenhouse gases from the atmosphere the oceans would freeze, probably to the equator. That's how big an effect the atmosphere has on oceans.
So, 100% nitrogen atmosphere you think would freeze the oceans? I think the problem with that thought experiment is that water would evaporate and thereby put more GHG (water is the most powerful one) back in even if you magically removed all water from the atmosphere. Case in point - ice caps on mars growing and shrinking.
You could never sustain a 50% increase in albedo. The clouds would quickly precipitate out in the cooling atmosphere.
Aren't clouds already precipitated? That is to say, aren't they just floating droplets of solid and liquid water? Now no doubt, clouds are tricky (sometimes they warm, sometimes they cool), but since we don't clearly understand all the drivers of that variation, it's difficult to ignore the large error bars that creates.
And where did you get that 0.001C number? Does it have any basis in reality?
Heat capacity of ocean water: 3993 J/kg/K Heat capacity of air: 1005 J/kg/K
energy content of the atmosphere is – 1005 *5×1018 kg =5 x1021 Joules/Degree Kelvin Energy content of the ocean is – 3993 *1.4×1021 =5.6×1024 Joules/Degree Kelvin
If you were to transfer enough ocean energy directly to the atmosphere to create 4 degrees of atmospheric warming, how much would that change the average temperature of the Earth’s water?
There are two different things. The theoretical forcing, and what we can actually measure.
Sigh. Okay, I'll bite, tell me what units a "forcing-o-mometer" reads in. Explain how forcing can be measured directly with some sort of ADC.
Gotcha. So Carbon doesn't cause global warming but apples do.
What? Did you *read* the falsifiable hypothesis statement? Apples (and other plants), because they act as a CO2 sink (excluding farming activity, as specified), cause *global cooling*.
Second, you do realize that the whole point of the science game isn't for me to say "I have a falsifiable hypothesis, therefore it is guaranteed to be right" -> it's "I have a falsifiable hypothesis, so now we can play the science game instead of religion".
So, your turn, where's your falsifiable hypothesis statement for AGW?:)
"It is important to understand that the null hypothesis can never be proven. A set of data can only reject a null hypothesis or fail to reject it."
*All* null hypotheses work the same way as the "each observable change of climate had a non-human cause" null hypothesis.
I've told you how to falsify AGW - falsify W or G or A. Shoul be easy enough. Start the experiments now.
That's like me telling you to falsify LGW (Leprechaun Global Warming) by falsifying W, G or L. W has happened over G in the pre-human past, so there's no doubt that it *can* happen without A (or the L's they invented).
Now tell me, how do you discern between NGW (natural global warming) and AGW or LGW? What *observations* would exclude any of them from being true? Be specific!
Well, now that you've accepted that AGW (and related) are falsifiable
Wait a sec, don't expand the scope of our agreement without checking first -> I've accepted that there is a falsifiable hypothesis of (A)AGW, which simply states that there is at least some minuscule positive effect from human emitted CO2. That does not mean that you've established a falsifiable hypothesis of AGW with a specific magnitude, nor the great grand daddy CAGW which insists that warming will be so severe that it will cause catastrophe. You've gotten a nanometer from me, and you're extending it to a kilometer without justification:)
You've also forgotten to answer my question. Perhaps some unconscious "denial" filter just missed it, so I'll state it again:
Are you simply supporting any *technically* true hypothesis of (A)AGW? Simply that the net impact of humanity's CO2 is positive, no matter *how* small?
A "yes" answer to that question, and I think we're both on the same page. A "no" answer on that question, and you'll have to help me understand your point of view more clearly.
explain to me where in any recent established philosophy of science (Popper or beyond), one actually makes a falsification hypothesis? Can you give specific examples?
Okay, Popper was born in 1902, so we'll consider roughly any 20th century scientific hypotheses.
First up, Quantum Mechanics. QM makes definite predictions and can be falsified. For example John Bell, in developing his inequalities, was attempting to falsify QM (he was a proponent of Bohm's theory). He showed that QM would have a higher correlation betwen states of separated entangled particles than would be consistent (on a naive view) with special relativity. But subsequent experiment showed that in fact nature does behave just this way, and relativistic locality has to be catered for with a more nuanced view. So this attempt to falsify QM failed. But the next attempt might just succeed!
Now, let me add a second question to you (don't forget to answer the first one above!):
Explain to me where in any recent established philosophy of science besides AGW (Popper or beyond), one actually does *not* make a falsifiable hypothesis? Can you give a specific example?
What? The measurements didn't *agree* with anything, they were processed, through a model, to come up with a theoretical number for forcing. What you're asking is "what model did the model agree with"!
1) Hypotheses: Apples are a forcing.
2) This would be falsified if temperature drops are followed by increased numbers of apples
Let's play with that for a moment:
1) Hypothesis: The growth of apples uses CO2, and therefore reduces the amount of warming in the atmosphere (by whatever trivial amount that may be), and can be considered ONLY a negative forcing, rather than a feedback (at any time).
2) This would be falsified if temperature drops are followed by increased number of apples (because in that case, if we show that dropping temperatures increase apples, which then lower temperature further, which then increase apples further, we've got a feedback, at least some of the time, right?)
Sounds reasonable to me. We of course gloss over a bunch of things that go into raising apple orchards up, but let's pretend for a moment that we're talking about apples in a world where there is no humanity, so we don't get confused with farming activity impacts.
Let's try this:
1) Hypothesis: plant growth can be considered ONLY a negative forcing, rather than a feedback (at any time)
2) This would be falsified if temperature drops are followed by increased plant growth, which then lower the temperature further, which then increase plant growth further, and so on.
Sounds like a reasonable falsifiable hypothesis statement. Of course for both plants and apples, we've got a bunch of confounding variables (like soil, solar radiation, etc, etc), but on its face, there's nothing particularly unscientific about either of those. They definitely would need polishing as you examined things closer, but they're both the start of the science game.
Ready to make your falsifiable hypothesis statement of AGW yet?:)
This is absurd. Because there were forest fires before the advent of humanity we know that all forest fires have a non-human cause.
No, what that means is that when we see a forest fire, the *default* assumption is that it was caused by non-human forces. You need to *prove* that humans caused it, you can't just assume that as default.
If we can't find the matches and the can of kerosene.
So...anytime we find matches and a can of kerosene, AGW is true...not sure if that's really a useful falsifiable hypothesis of AGW.
My hypothesis would be that each change of climate had a cause.
A rose by any other name. If your hypothesis is that each change of climate had some unspecified cause, how is that different than "natural unspecified causes"?
How about this for the null hypothesis - "each observable change of climate had a non-human cause". We know this to be true because we had climate change well before the advent of humanity.
Now that we've established the null, what is your falsifiable hypothesis statement of AGW?
Yeah, except that we can also measure it thanks to the magic of modern satellites. Remember the very first post? And guess what? The measurements confirm the expected results.
Do you understand the difference between a model and a measurement?
The measurements, when pushed through a model, give us a theoretical result. As you've seen, the model has been modified over the years, and has given *different* theoretical results.
Or are you claiming that early measurements had some sort of error in them, and that the last measurements that we took are definitely right on the money?
"The result (of F) can be determined... with no reference to changes in the Earth’s temperature."
And the result apparently doesn't have a static determination, does it, if it keeps changing over time:)
Try again:)
Hey, I'm not the one that said that volcanoes impact the climate. You did.
I made a falsifiable hypothesis statement as to whether or not volcanoes were forcings or feedbacks. You made the hand waving claim that my falsifiable hypothesis statement was improper, without providing an alternative falsifiable hypothesis statement that *was* proper. Then you made the claim that no falsifiable hypothesis statement could even *exist* for it.
I understand your point, but it is also beside the point. You said AGW is not falsifiable, but it simply is.
I had expected you to actually have a hypothesis statement that made some sort of magnitude claim on AGW, not just a direction. So yes, the theory of AAGW is falsifiable (Any Anthropogenic Global Warming), just as the theory of ANAGW is falsifiable (Any Non Anthropogenic Global Warming). But neither of these theories really say much.
Proving the case for AGW or CAGW (which involves risk management), is simply a different problem.
No, CAGW and a SAOAGW (Catastrophic Anthropogenic Global Warming and Specific Amount Of Anthropogenic Global Warming) both need their own falsifiable hypothesis statements - so the "problem", from a science point of view, starts off with the same first step.
As is so typical in discussions like this, instead of back-tracking and saying, "Oh yes, I see, AGW *is* falsifiable", you have tried to change the context of the discussion.
Actually, I was inviting you to define the context so we could speak with understanding. When you finally defined the context as AAGW (Any Anthropogenic Global Warming), my previous misunderstanding as to your point of view was clarified, even though I was surprised you went in that direction.
So, again, let me explicitly ask a question I don't think you've answered yet, so I don't make you jump to logically consistent conclusions you may have a different rationale for:
Are you simply supporting any *technically* true hypothesis of (A)AGW? Simply that the net impact of humanity's CO2 is positive, no matter *how* small?
A "yes" answer to that question, and I think we're both on the same page. A "no" answer on that question, and you'll have to help me understand your point of view more clearly.
AGW can be falsified -- for example, showing zero forcing for CO2.
That is DIFFERENT to saying that you can prove AGW with non-zero forcing of CO2.
I completely understand what you're saying, but I don't think you're really understanding the reply. Let me try again.
A hypothesis of AGW that is falsified by showing zero forcing for CO2 only promises us a *direction* of effect, not a *magnitude*.
Take this list of potential observations:
Forcing for CO2 = -1 HYPOTHESIS FALSIFIED Forcing for CO2 = 0 HYPOTHESIS FALSIFIED Forcing for CO2 = 0.000000000000000000000000000000000000001 HYPOTHESIS NOT FALSIFIED ("CONSISTENT") Forcing for CO2 = 1000000000000000000000000000000000000000 HYPOTHESIS NOT FALSIFIED ("CONSISTENT")
It is quite possible according to your stated falsifiable hypothesis of AGW (falsified by CO2 forcing non-CO2 forcing" (requiring fairly detailed specification of all non-CO2 forcings - perhaps practically unfalsifiable)? Or do you want to modify your falsifiable hypothesis to say, "CO2 forcing > 5.0"? Or make some other magnitude claim, rather than just a direction claim?
I am saying that zero forcing falsifies AGW, which is what falsifiability is about.
That's exactly what I understood you meant - do you understand my critique that without any magnitude placed on that, your falsifiable hypothesis of AGW doesn't offer any particularly informative information?
"natural climate change" is not the null hypothesis because it's not a hypothesis.
Really? You're gonna hang your hat on that?
Say, what would you make the null hypothesis? All climate change is caused by humanity? Not sure how that one explains climate changes before humans, but maybe you also believe the world was created in 7 days 4004 years ago?:)
The default, or general position on climate change must be that it changes naturally - you don't have to specify, measure, or enumerate all the different variables involved in climate change for that to be the null hypothesis, all you have to do is look at the fairly incontrovertible fact that climate has changed long before humanity and anything "un-natural" has ever happened.
Now, make your clear statement of what CO2 levels and global average temperature would falsify your hypothesis of AGW if observed next year, in 5 years, or heck, even in 30 years. Add additional variables if you'd like, but be specific (otherwise you're just opening up the door to future ad hoc special pleadings).
If you can't even start the with a clear falsifiable hypothesis statement, you're not playing the science game.
I'm going to assert that the effect the atmosphere has on oceans has to do with cloud cover and albedo, moderating the amount of sunlight that warms the oceans. If you magically raised the average temperature of the atmosphere by say, 4C, but increased the albedo to block 50% of the sunlight that reaches the oceans, the 4C of extra atmospheric energy would be absorbed by the oceans with less than 0.001C change in ocean temperature, and then the ocean temps would fall precipitously with a lack of solar radiation.
So while certainly what happens in one affects the other, the capacity of the oceans is orders of magnitudes greater, and the effect on oceans of atmospheric heat is probably undetectable over any period of time (while the reverse is *certainly* not true).
By the way, we can measure the spectral radiance both at the top of the atmosphere and down here on Earth. The measurements confirm F.
What measurements? Listen to Curry again:
"The result can be determined by fitting a regression line through the simulation results from radiative transfer models with no reference to changes in the Earth’s temperature. the use of this expression is mainly as an hueristic in the context of simple back of the envelope arguments."
F is the result of a *model*, not a measurement. Let's look back at the history of this *calculated* value:
If Lindzen is correct that sensitivity is 0.7C per doubling of CO2, the corresponding change in forcing should be
delta F = (1.2)(delta T) =.84 W/m2 = 1.2*ln(2)
thus the “IPCC formula” “should be” approx.
delta F = 1.2*ln(C/Co)
Say it again with me "F is the result of a *model*, not a measurement.":)
So therefore you cannot prove that volcanoes have an impact on the climate?
Not without making a falsifiable hypothesis statement. You're mistaking the game of common sense for the game of science. The science game has rules, common sense is just convention.
Can you provide proof that would satisfy the bottomless pit of incredulity that is HSThompson?
You're asking me to prove *your* point for you? Now what kind of science game is that!?
Look, you want to argue religion, that's fine - I'm more than happy to tear down your beliefs. If you want to argue science, start with your falsifiable hypothesis statement.
so the centre of the Earth was behind heating the oceans, then?
I believe you mean *is*, not *was*. Or is your belief that the oceans actually heat the center of the earth (much like what seems like a belief that the atmosphere is what heats the oceans)?
water is a heat sink. it can't change itself - it needs energy put in.
Agreed. Ever hear of the tides? Ever wonder where that energy comes from?
I'll assert that energy gets put into the oceans by the tides thanks to the moon, internal heat from the earth, and solar radiation. If the atmosphere does anything at all to moderate ocean heat, it's through the reflection of solar radiation (variances in cloud cover and type).
It would certainly be interesting to imagine that you could heat the oceans by warming the gas above them - I invite you to take a pot of water, and try to boil it by heating the air immediately above. Make special note of how much hotter you need to make the gas above your pot of water in order to heat it say, 1C in 1 hour.
Radiative forcing of CO2 is 0 implies AGW is false.
Thank you for the clarification - I now understand your hypothesis as one that makes *zero* claim on magnitude, simply a claim on sign, much like the hypothesis "if you're a scorpio, you are Loyal, Passionate, Resourceful, Observant and Dynamic" (since every one of those traits exist at a trivial level in *everyone*, and we carefully avoid making any claims on magnitude that might be shown wrong).
I also now understand your hypothesis as one that makes no claims on beneficial or harmful impact, although that might be reading too much into it.
I guess now the problem I have is that Radiative forcing of CO2 > 0 also implies NAGW is true as well (non-anthropogenic global warming caused by other animals). Heck, even non-animal emissions of CO2 (say dying plants) would imply DPGW is true. We could go further and also assert that it implies LPGC is true as well (living plant global cooling), since they consume CO2. But none of these hypotheses seems to have any useful predictions, don't you agree?
As per Popper "Every "good" scientific theory is a prohibition: it forbids certain things to happen. The more a theory forbids, the better it is." - none of these theories seem to forbid much at all.
Remember, we are talking about falsifiability. Popper was not provability.
I'm not sure if I understand your distinction - Popper never mentions the term "provability". Do you mean "practical falsifiability"? The general understanding I have is that "falsifiability" == "provability" according to Popper.
That is exactly what people in denial do. You said that AGW is not falsifiable, but you are simply wrong.
Actually, I claimed AGW was not falsifiable because I did not realize the incredibly limited claims you really intended to make - I'll agree, AGW as you've defined it (radiative forcing of CO2 > 0) is falsifiable, the problem is, I think you've won the battle to lose the war. By your AGW definition, we can also assert NAGW, DPGW and LPGC - all of them being trivially true, without making any real useful predictions at all (since we avoid magnitude of any sort here). It's like asserting the hypothesis "gravity is a force that pulls objects together", rather than saying F = G(m1*m2/r2). Yes, "gravity is a force that pulls objects together" is trivially true, but not very informative.
So tell me, do people in denial often concentrate on a semantic victory while not realizing they've actually managed to refute their basic premises?:) Or am I being unfair to you, by inferring that you are a warmist who has undermined their own argument, rather than a lukewarmist who was simply trying to make a technically true point?
While hard to imagine Antarctica becoming a temperate paradise without a major change in incoming solar radiation (or additional "greenhouse" gases if one prefers), it seems that much of the change has to do with large conveyer belt currents.
Just from a heat capacity point of view, if we want to understand climate better, the atmosphere probably isn't nearly as important as the oceans.
Let's try the lasty first go to surfacestations.org and then to www.ncdc.noaa.gov and compare site photos.
Any specific URLs, or should I simply browse through all of them looking for examples you'd interpret as shady?
Second point Watts supports Spencers claim that clouds are causing warming. Watts supports Spencer deliberately choice of model data and observations that the greatest difference. Using the same approach as the difference can be made nearly zero.
So you'd fight a cherry pick with another cherry pick?:) It sounds like you're having a philosophical disagreement rather than showing a substantive refutation. Remember, all that is necessary for a hypothesis to be wrong is *one* refutation, even if it's cherry picked. A hypothesis needs to survive attempts at falsification (or at least have some sort of defined falsification).
I think Watts and Spencer are saying something a bit more subtle - the effect of clouds is not easily observable, calculated, and can have such an big impact that you cannot make models and plug anything realistic into them. Demonstrating how far off things can be with a single example is sufficient to show how unskilled the models are.
So you can just hand wave natural causes without saying what they are? Guess what. Every conceivable natural cause has been evaluated many times. Some of the warming is natural. Most isn't.
I don't have to hand wave - natural climate change is the null hypothesis. Climate has changed since before humanity existed - there's no particular reason we should believe that humans have completely taken over control of the climate.
Guess what - you have *no idea* what the various variables, components, and other causes of climate change are, much less have any way of attributing with any sort of confidence a magnitude to them. Every worm that aerates the soil has an effect on climate - care to tell me what that effect was evaluated to?
One spike 15 years ago doesn't change that.
You're making an ad hoc special pleading for the spike you didn't predict. Try this on for size - make a clear statement as to what observations of CO2 levels and temperature would falsify your hypothesis. Be specific.
So we should wait 30 years before we do anything? I guess it's easier to die than admit you are wrong.
There is no reason for me to believe that your claims of apocalypse are true, be it 5, 10, 30 or 100 years from now, and even less reason for me to believe that any of your proposed remediations would be benign. The road to hell is paved with the precautionary principle.
There are many falsifiable hypothesis that make up global warming theory.
Do you have a list? Or do you simply take it on faith that it is so?
+ Insufficient radiative forcing of CO2 + Warming attributed to Sun (correlated change is solar irradience)
I don't think you're being very honest with yourself here. Let's be more specific about your two points, and see if we can get some clarity.
"Insufficient radiative forcing of CO2", I take it, means simply calculating based on spectral analysis, a proposed theoretical radiative forcing. (References below from: http://www.john-daly.com/bull-121.htm)
Wigley (1987): Delta F = 6.333 ln (C/C0)
So in 1987, one might say, "if Delta F does not equal 6.333 ln (C/Co), radiative forcing of CO2 is insufficient to support the AGW hypothesis". That's a specific prediction, and an acceptance of falsifiability. What happens next?
Houghton et al 1990: Delta F = 6.3 ln (C/Co)
So now it's 1990. Radiative forcing has now been calculated slightly lower. Has AGW been falsified? Nope, we simply lower the bar (or shift the goalposts), and now we state "if Delta F does not equal 6.3 ln (C/Co) radiative forcing of CO2 is insufficient to support the AGW hypothesis". Another specific prediction but an avoidance of responsibility for the first one. What happens next?
Myhre et al 1998: Delta F = 5.35 ln (C/Co)
So now it's 1998. Radiative forcing has now been calculated even more significantly lower. Has AGW been falsified?
How much lower do we need to go before we can no longer avoid responsibility for our predictions, and accept AGW as falsified?
If Lindzen is correct that sensitivity is 0.7C per doubling of CO2, the corresponding change in forcing should be
delta F = (1.2)(delta T) =.84 W/m2 = 1.2*ln(2)
thus the “IPCC formula” “should be” approx.
delta F = 1.2*ln(C/Co)
So now we're even farther away from the original prediction. Has AGW been falsified? How about this devil's advocate position - it isn't falsified until Delta F goes negative, because it is theoretically possibly to attribute 100% of all CO2 in the atmosphere to humanity, and if we accept that CO2 *always* adds warming (a stipulation at this point), then no matter how small the warming effect of CO2, we can assert AGW is at the very least technically true.
Now, are you arguing for the "at the very least technically true AGW"? Again, I don't want to put up a straw man you're not trying to defend, but you're not being specific enough in your assertions of what AGW really is.
+ Warming attributed to Sun (correlated change is solar irradience)
Okay, this one is a pretty obvious logical fallacy - the argument from ignorance. Saying that "if you don't have a better explanation, then my explanation must be true" is not a scientific argument, even if it *is* clever. The null hypothesis, I think we can both agree, is that climate changes due to natural forces. We can trivially observe that climate change existed before humanity, and there is no particular reason we should believe that humanity (as opposed to say, the rise of the arthopods, or dinosaurs, or any other widespread lifeform on the planet) has the unique ability to suddenly take control of the weather and climate. Note, I'm not saying it isn't *possible*, I'm simply saying that it must be held to strict scrutiny.
And again, devil's advocate - even if solar irradiance explained 99% of the warming observed (assuming we has some rock solid understanding of all the other confounding variables), even 1% of uncertainty there could leave AGW *technically* true, even if miniscule.
So here are the questions outstanding to you:
1) did the change in the calculated forcing over the decades falsify AGW? 2) can any change in the calculated forcing falsify A
Slashdot Mirror
So let's be very clear here - you're measuring spectral radiance for the spectrum that you're interested in. After that, you're using a model to decide what forcing is.
So what you have is a spectral-radiance-o-mometer, not a forcing-o-mometer. You've got a model which derives a theoretical forcing from your spectral-radiance-o-mometer.
Understand your error now? :)
What, you're asserting that apples and plants are a feedback for global cooling? Really?
Or are you going to make the bold assertion that apples and other plants have no effect on climate at all?
Fail - you've taken disparate falsifiable hypotheses, and simply asserted that they combine in some unspecified way to show AGW. Each link in the chain is subject to strict scrutiny in order for the chain to hold together :)
Let's revisit your proposed null hypothesis:
"My hypothesis would be that each change of climate had a cause."
Explain how that hypothesis is any more falsifiable than "each change of climate had a natural cause". Demonstrate how you could observe a change of climate without any cause, natural or unnatural.
"It's natural" is a perfectly valid null hypothesis, because it states clearly that the beginning of our knowledge is an empty set. We don't have to rely on "it was aliens" or "it was leprechauns" or "it was humans" or "it was god" - without any specifically defined cause, we know that left to its own devices, climate and weather have changed without humanity or any other intelligent or sentient power causing things to happen.
I believe you mean (A)AGW, but correct me if you for some reason think I've misinterpreted your meaning, and you *intended* to leave that out as an important caveat. When you say "I am saying that AGW is *technically* falsifiable", that sounds like a yes answer to "Simply that the net impact of humanity's CO2 is positive, no matter *how* small".
Put in your terms:
Fact: (A)AGW is falsifiable because it makes empirically testable predictions. It makes no claims as to the magnitude of warming due to CO2, only that it is at least infinitesimally positive. FULL STOP.
Not to prejudge your answer before you've had a chance to give it, I would imagine that disagreeing with that fact means that you believe that (A)AGW == AGW for all intents and purposes. If that's true, please explain why you would consider those two functionally equivalent.
Oops. You forgot again to answer my questions. Perhaps the idea of the questions isn't sitting well with your unconscious denial. Here they are again:
1) Are you simply supporting any *technically* true hypothesis of (A)AGW? Simply that the net impact of humanity's CO2 is positive, no matter *how* small?
A "yes" answer to that question, and I think we're both on the same page. A "no" answer on that question, and you'll have to help me understand your point of view more clearly.
2) Explain to me where in any recent established philosophy of science besides AGW (Popper or beyond), one actually does *not* make a falsifiable hypothesis? Can you give a specific example?
Your hypothesis of (A)AGW (any anthropogenic global warming) does make falsifiable predictions, but not very useful ones. You still haven't found a hypothesis of AGW with any sort of specific magnitude that can be falsified, although I invite you to do so.
Again, try to respond with your next post answers to my questions, and help bring more understanding to the conversation. I know they may not sit well in your mind, but take a while and try to overcome the difficulty you're having thinking about them!
So, 100% nitrogen atmosphere you think would freeze the oceans? I think the problem with that thought experiment is that water would evaporate and thereby put more GHG (water is the most powerful one) back in even if you magically removed all water from the atmosphere. Case in point - ice caps on mars growing and shrinking.
Aren't clouds already precipitated? That is to say, aren't they just floating droplets of solid and liquid water? Now no doubt, clouds are tricky (sometimes they warm, sometimes they cool), but since we don't clearly understand all the drivers of that variation, it's difficult to ignore the large error bars that creates.
http://wattsupwiththat.com/2011/04/06/energy-content-the-heat-is-on-atmosphere-vs-ocean/
Heat capacity of ocean water: 3993 J/kg/K
Heat capacity of air: 1005 J/kg/K
energy content of the atmosphere is – 1005 *5×1018 kg =5 x1021 Joules/Degree Kelvin
Energy content of the ocean is – 3993 *1.4×1021 =5.6×1024 Joules/Degree Kelvin
If you were to transfer enough ocean energy directly to the atmosphere to create 4 degrees of atmospheric warming, how much would that change the average temperature of the Earth’s water?
0.001 Degrees C of ocean temp change
Sigh. Okay, I'll bite, tell me what units a "forcing-o-mometer" reads in. Explain how forcing can be measured directly with some sort of ADC.
What? Did you *read* the falsifiable hypothesis statement? Apples (and other plants), because they act as a CO2 sink (excluding farming activity, as specified), cause *global cooling*.
Second, you do realize that the whole point of the science game isn't for me to say "I have a falsifiable hypothesis, therefore it is guaranteed to be right" -> it's "I have a falsifiable hypothesis, so now we can play the science game instead of religion".
So, your turn, where's your falsifiable hypothesis statement for AGW? :)
You still don't understand what the null hypothesis is, do you? Here: http://en.wikipedia.org/wiki/Null_hypothesis
"It is important to understand that the null hypothesis can never be proven. A set of data can only reject a null hypothesis or fail to reject it."
*All* null hypotheses work the same way as the "each observable change of climate had a non-human cause" null hypothesis.
That's like me telling you to falsify LGW (Leprechaun Global Warming) by falsifying W, G or L. W has happened over G in the pre-human past, so there's no doubt that it *can* happen without A (or the L's they invented).
Now tell me, how do you discern between NGW (natural global warming) and AGW or LGW? What *observations* would exclude any of them from being true? Be specific!
Wait a sec, don't expand the scope of our agreement without checking first -> I've accepted that there is a falsifiable hypothesis of (A)AGW, which simply states that there is at least some minuscule positive effect from human emitted CO2. That does not mean that you've established a falsifiable hypothesis of AGW with a specific magnitude, nor the great grand daddy CAGW which insists that warming will be so severe that it will cause catastrophe. You've gotten a nanometer from me, and you're extending it to a kilometer without justification :)
You've also forgotten to answer my question. Perhaps some unconscious "denial" filter just missed it, so I'll state it again:
Are you simply supporting any *technically* true hypothesis of (A)AGW? Simply that the net impact of humanity's CO2 is positive, no matter *how* small?
A "yes" answer to that question, and I think we're both on the same page. A "no" answer on that question, and you'll have to help me understand your point of view more clearly.
Okay, Popper was born in 1902, so we'll consider roughly any 20th century scientific hypotheses.
First up, Quantum Mechanics. QM makes definite predictions and can be falsified. For example John Bell, in developing his inequalities, was attempting to falsify QM (he was a proponent of Bohm's theory). He showed that QM would have a higher correlation betwen states of separated entangled particles than would be consistent (on a naive view) with special relativity. But subsequent experiment showed that in fact nature does behave just this way, and relativistic locality has to be catered for with a more nuanced view. So this attempt to falsify QM failed. But the next attempt might just succeed!
Second up, DNA vs. protein replication. Here's the relevant experiment: http://en.wikipedia.org/wiki/Avery-MacLeod-McCarty_experiment
Now, let me add a second question to you (don't forget to answer the first one above!):
Explain to me where in any recent established philosophy of science besides AGW (Popper or beyond), one actually does *not* make a falsifiable hypothesis? Can you give a specific example?
What? The measurements didn't *agree* with anything, they were processed, through a model, to come up with a theoretical number for forcing. What you're asking is "what model did the model agree with"!
Let's play with that for a moment:
1) Hypothesis: The growth of apples uses CO2, and therefore reduces the amount of warming in the atmosphere (by whatever trivial amount that may be), and can be considered ONLY a negative forcing, rather than a feedback (at any time).
2) This would be falsified if temperature drops are followed by increased number of apples (because in that case, if we show that dropping temperatures increase apples, which then lower temperature further, which then increase apples further, we've got a feedback, at least some of the time, right?)
Sounds reasonable to me. We of course gloss over a bunch of things that go into raising apple orchards up, but let's pretend for a moment that we're talking about apples in a world where there is no humanity, so we don't get confused with farming activity impacts.
Let's try this:
1) Hypothesis: plant growth can be considered ONLY a negative forcing, rather than a feedback (at any time)
2) This would be falsified if temperature drops are followed by increased plant growth, which then lower the temperature further, which then increase plant growth further, and so on.
Sounds like a reasonable falsifiable hypothesis statement. Of course for both plants and apples, we've got a bunch of confounding variables (like soil, solar radiation, etc, etc), but on its face, there's nothing particularly unscientific about either of those. They definitely would need polishing as you examined things closer, but they're both the start of the science game.
Ready to make your falsifiable hypothesis statement of AGW yet? :)
No, what that means is that when we see a forest fire, the *default* assumption is that it was caused by non-human forces. You need to *prove* that humans caused it, you can't just assume that as default.
So...anytime we find matches and a can of kerosene, AGW is true...not sure if that's really a useful falsifiable hypothesis of AGW.
Care to try again?
A rose by any other name. If your hypothesis is that each change of climate had some unspecified cause, how is that different than "natural unspecified causes"?
How about this for the null hypothesis - "each observable change of climate had a non-human cause". We know this to be true because we had climate change well before the advent of humanity.
Now that we've established the null, what is your falsifiable hypothesis statement of AGW?
Do you understand the difference between a model and a measurement?
The measurements, when pushed through a model, give us a theoretical result. As you've seen, the model has been modified over the years, and has given *different* theoretical results.
Or are you claiming that early measurements had some sort of error in them, and that the last measurements that we took are definitely right on the money?
And the result apparently doesn't have a static determination, does it, if it keeps changing over time :)
Try again :)
I made a falsifiable hypothesis statement as to whether or not volcanoes were forcings or feedbacks. You made the hand waving claim that my falsifiable hypothesis statement was improper, without providing an alternative falsifiable hypothesis statement that *was* proper. Then you made the claim that no falsifiable hypothesis statement could even *exist* for it.
What will you think of next? :)
I had expected you to actually have a hypothesis statement that made some sort of magnitude claim on AGW, not just a direction. So yes, the theory of AAGW is falsifiable (Any Anthropogenic Global Warming), just as the theory of ANAGW is falsifiable (Any Non Anthropogenic Global Warming). But neither of these theories really say much.
No, CAGW and a SAOAGW (Catastrophic Anthropogenic Global Warming and Specific Amount Of Anthropogenic Global Warming) both need their own falsifiable hypothesis statements - so the "problem", from a science point of view, starts off with the same first step.
Actually, I was inviting you to define the context so we could speak with understanding. When you finally defined the context as AAGW (Any Anthropogenic Global Warming), my previous misunderstanding as to your point of view was clarified, even though I was surprised you went in that direction.
So, again, let me explicitly ask a question I don't think you've answered yet, so I don't make you jump to logically consistent conclusions you may have a different rationale for:
Are you simply supporting any *technically* true hypothesis of (A)AGW? Simply that the net impact of humanity's CO2 is positive, no matter *how* small?
A "yes" answer to that question, and I think we're both on the same page. A "no" answer on that question, and you'll have to help me understand your point of view more clearly.
I completely understand what you're saying, but I don't think you're really understanding the reply. Let me try again.
A hypothesis of AGW that is falsified by showing zero forcing for CO2 only promises us a *direction* of effect, not a *magnitude*.
Take this list of potential observations:
Forcing for CO2 = -1 HYPOTHESIS FALSIFIED
Forcing for CO2 = 0 HYPOTHESIS FALSIFIED
Forcing for CO2 = 0.000000000000000000000000000000000000001 HYPOTHESIS NOT FALSIFIED ("CONSISTENT")
Forcing for CO2 = 1000000000000000000000000000000000000000 HYPOTHESIS NOT FALSIFIED ("CONSISTENT")
It is quite possible according to your stated falsifiable hypothesis of AGW (falsified by CO2 forcing non-CO2 forcing" (requiring fairly detailed specification of all non-CO2 forcings - perhaps practically unfalsifiable)? Or do you want to modify your falsifiable hypothesis to say, "CO2 forcing > 5.0"? Or make some other magnitude claim, rather than just a direction claim?
That's exactly what I understood you meant - do you understand my critique that without any magnitude placed on that, your falsifiable hypothesis of AGW doesn't offer any particularly informative information?
Really? You're gonna hang your hat on that?
Say, what would you make the null hypothesis? All climate change is caused by humanity? Not sure how that one explains climate changes before humans, but maybe you also believe the world was created in 7 days 4004 years ago? :)
The default, or general position on climate change must be that it changes naturally - you don't have to specify, measure, or enumerate all the different variables involved in climate change for that to be the null hypothesis, all you have to do is look at the fairly incontrovertible fact that climate has changed long before humanity and anything "un-natural" has ever happened.
Now, make your clear statement of what CO2 levels and global average temperature would falsify your hypothesis of AGW if observed next year, in 5 years, or heck, even in 30 years. Add additional variables if you'd like, but be specific (otherwise you're just opening up the door to future ad hoc special pleadings).
If you can't even start the with a clear falsifiable hypothesis statement, you're not playing the science game.
I'm going to assert that the effect the atmosphere has on oceans has to do with cloud cover and albedo, moderating the amount of sunlight that warms the oceans. If you magically raised the average temperature of the atmosphere by say, 4C, but increased the albedo to block 50% of the sunlight that reaches the oceans, the 4C of extra atmospheric energy would be absorbed by the oceans with less than 0.001C change in ocean temperature, and then the ocean temps would fall precipitously with a lack of solar radiation.
So while certainly what happens in one affects the other, the capacity of the oceans is orders of magnitudes greater, and the effect on oceans of atmospheric heat is probably undetectable over any period of time (while the reverse is *certainly* not true).
What measurements? Listen to Curry again:
"The result can be determined by fitting a regression line through the simulation results from radiative transfer models with no reference to changes in the Earth’s temperature. the use of this expression is mainly as an hueristic in the context of simple back of the envelope arguments."
F is the result of a *model*, not a measurement. Let's look back at the history of this *calculated* value:
Wigley (1987): Delta F = 6.333 ln (C/C0)
Houghton et al 1990: Delta F = 6.3 ln (C/Co)
Myhre et al 1998: Delta F = 5.35 ln (C/Co)
Lindzen and Choi 2011:
http://www-eaps.mit.edu/faculty/lindzen/236-Lindzen-Choi-2011.pdf
If Lindzen is correct that sensitivity is 0.7C per doubling of CO2, the corresponding change in forcing should be
delta F = (1.2)(delta T) = .84 W/m2 = 1.2*ln(2)
thus the “IPCC formula” “should be” approx.
delta F = 1.2*ln(C/Co)
Say it again with me "F is the result of a *model*, not a measurement." :)
Not without making a falsifiable hypothesis statement. You're mistaking the game of common sense for the game of science. The science game has rules, common sense is just convention.
You're asking me to prove *your* point for you? Now what kind of science game is that!?
Look, you want to argue religion, that's fine - I'm more than happy to tear down your beliefs. If you want to argue science, start with your falsifiable hypothesis statement.
I believe you mean *is*, not *was*. Or is your belief that the oceans actually heat the center of the earth (much like what seems like a belief that the atmosphere is what heats the oceans)?
Agreed. Ever hear of the tides? Ever wonder where that energy comes from?
I'll assert that energy gets put into the oceans by the tides thanks to the moon, internal heat from the earth, and solar radiation. If the atmosphere does anything at all to moderate ocean heat, it's through the reflection of solar radiation (variances in cloud cover and type).
It would certainly be interesting to imagine that you could heat the oceans by warming the gas above them - I invite you to take a pot of water, and try to boil it by heating the air immediately above. Make special note of how much hotter you need to make the gas above your pot of water in order to heat it say, 1C in 1 hour.
My point exactly. A warmer world has nicer climates.
What about this Antarctica you mention? Wouldn't that be pleasant if it were a temperate zone? :)
Thank you for the clarification - I now understand your hypothesis as one that makes *zero* claim on magnitude, simply a claim on sign, much like the hypothesis "if you're a scorpio, you are Loyal, Passionate, Resourceful, Observant and Dynamic" (since every one of those traits exist at a trivial level in *everyone*, and we carefully avoid making any claims on magnitude that might be shown wrong).
I also now understand your hypothesis as one that makes no claims on beneficial or harmful impact, although that might be reading too much into it.
I guess now the problem I have is that Radiative forcing of CO2 > 0 also implies NAGW is true as well (non-anthropogenic global warming caused by other animals). Heck, even non-animal emissions of CO2 (say dying plants) would imply DPGW is true. We could go further and also assert that it implies LPGC is true as well (living plant global cooling), since they consume CO2. But none of these hypotheses seems to have any useful predictions, don't you agree?
As per Popper "Every "good" scientific theory is a prohibition: it forbids certain things to happen. The more a theory forbids, the better it is." - none of these theories seem to forbid much at all.
I'm not sure if I understand your distinction - Popper never mentions the term "provability". Do you mean "practical falsifiability"? The general understanding I have is that "falsifiability" == "provability" according to Popper.
Actually, I claimed AGW was not falsifiable because I did not realize the incredibly limited claims you really intended to make - I'll agree, AGW as you've defined it (radiative forcing of CO2 > 0) is falsifiable, the problem is, I think you've won the battle to lose the war. By your AGW definition, we can also assert NAGW, DPGW and LPGC - all of them being trivially true, without making any real useful predictions at all (since we avoid magnitude of any sort here). It's like asserting the hypothesis "gravity is a force that pulls objects together", rather than saying F = G(m1*m2/r2). Yes, "gravity is a force that pulls objects together" is trivially true, but not very informative.
So tell me, do people in denial often concentrate on a semantic victory while not realizing they've actually managed to refute their basic premises? :) Or am I being unfair to you, by inferring that you are a warmist who has undermined their own argument, rather than a lukewarmist who was simply trying to make a technically true point?
I used it as a case example of extreme heat, extremely large areas of habitability and extreme biodiversity amongst the non-homo genus species :)
I'm more than happy to argue against any assertion that a warmer world may be good for humanity, but worse for life as a whole.
Of interesting note, the cooling which followed the Late Eocene was driven by ocean currents:
http://www.sciencedaily.com/releases/2011/05/110526141406.htm
While hard to imagine Antarctica becoming a temperate paradise without a major change in incoming solar radiation (or additional "greenhouse" gases if one prefers), it seems that much of the change has to do with large conveyer belt currents.
Just from a heat capacity point of view, if we want to understand climate better, the atmosphere probably isn't nearly as important as the oceans.
Any specific URLs, or should I simply browse through all of them looking for examples you'd interpret as shady?
So you'd fight a cherry pick with another cherry pick? :) It sounds like you're having a philosophical disagreement rather than showing a substantive refutation. Remember, all that is necessary for a hypothesis to be wrong is *one* refutation, even if it's cherry picked. A hypothesis needs to survive attempts at falsification (or at least have some sort of defined falsification).
I think Watts and Spencer are saying something a bit more subtle - the effect of clouds is not easily observable, calculated, and can have such an big impact that you cannot make models and plug anything realistic into them. Demonstrating how far off things can be with a single example is sufficient to show how unskilled the models are.
I don't have to hand wave - natural climate change is the null hypothesis. Climate has changed since before humanity existed - there's no particular reason we should believe that humans have completely taken over control of the climate.
Guess what - you have *no idea* what the various variables, components, and other causes of climate change are, much less have any way of attributing with any sort of confidence a magnitude to them. Every worm that aerates the soil has an effect on climate - care to tell me what that effect was evaluated to?
You're making an ad hoc special pleading for the spike you didn't predict. Try this on for size - make a clear statement as to what observations of CO2 levels and temperature would falsify your hypothesis. Be specific.
There is no reason for me to believe that your claims of apocalypse are true, be it 5, 10, 30 or 100 years from now, and even less reason for me to believe that any of your proposed remediations would be benign. The road to hell is paved with the precautionary principle.
Do you have a list? Or do you simply take it on faith that it is so?
I don't think you're being very honest with yourself here. Let's be more specific about your two points, and see if we can get some clarity.
"Insufficient radiative forcing of CO2", I take it, means simply calculating based on spectral analysis, a proposed theoretical radiative forcing. (References below from: http://www.john-daly.com/bull-121.htm)
Wigley (1987): Delta F = 6.333 ln (C/C0)
So in 1987, one might say, "if Delta F does not equal 6.333 ln (C/Co), radiative forcing of CO2 is insufficient to support the AGW hypothesis". That's a specific prediction, and an acceptance of falsifiability. What happens next?
Houghton et al 1990: Delta F = 6.3 ln (C/Co)
So now it's 1990. Radiative forcing has now been calculated slightly lower. Has AGW been falsified? Nope, we simply lower the bar (or shift the goalposts), and now we state "if Delta F does not equal 6.3 ln (C/Co) radiative forcing of CO2 is insufficient to support the AGW hypothesis". Another specific prediction but an avoidance of responsibility for the first one. What happens next?
Myhre et al 1998: Delta F = 5.35 ln (C/Co)
So now it's 1998. Radiative forcing has now been calculated even more significantly lower. Has AGW been falsified?
How much lower do we need to go before we can no longer avoid responsibility for our predictions, and accept AGW as falsified?
Lindzen and Choi 2011:
http://www-eaps.mit.edu/faculty/lindzen/236-Lindzen-Choi-2011.pdf
If Lindzen is correct that sensitivity is 0.7C per doubling of CO2, the corresponding change in forcing should be
delta F = (1.2)(delta T) = .84 W/m2 = 1.2*ln(2)
thus the “IPCC formula” “should be” approx.
delta F = 1.2*ln(C/Co)
So now we're even farther away from the original prediction. Has AGW been falsified? How about this devil's advocate position - it isn't falsified until Delta F goes negative, because it is theoretically possibly to attribute 100% of all CO2 in the atmosphere to humanity, and if we accept that CO2 *always* adds warming (a stipulation at this point), then no matter how small the warming effect of CO2, we can assert AGW is at the very least technically true.
Now, are you arguing for the "at the very least technically true AGW"? Again, I don't want to put up a straw man you're not trying to defend, but you're not being specific enough in your assertions of what AGW really is.
Okay, this one is a pretty obvious logical fallacy - the argument from ignorance. Saying that "if you don't have a better explanation, then my explanation must be true" is not a scientific argument, even if it *is* clever. The null hypothesis, I think we can both agree, is that climate changes due to natural forces. We can trivially observe that climate change existed before humanity, and there is no particular reason we should believe that humanity (as opposed to say, the rise of the arthopods, or dinosaurs, or any other widespread lifeform on the planet) has the unique ability to suddenly take control of the weather and climate. Note, I'm not saying it isn't *possible*, I'm simply saying that it must be held to strict scrutiny.
And again, devil's advocate - even if solar irradiance explained 99% of the warming observed (assuming we has some rock solid understanding of all the other confounding variables), even 1% of uncertainty there could leave AGW *technically* true, even if miniscule.
So here are the questions outstanding to you:
1) did the change in the calculated forcing over the decades falsify AGW?
2) can any change in the calculated forcing falsify A