This is the language of science bucko. Get used to it. Clearly they are consistent.
Ah, the Layzej "Speculation Is Science" axiom. Got it:)
The non-anthropogenic portion of the CO2 is preexisting. It is not causing a change in the climate.
Of course not. Climate never changed before humans started releasing CO2, so obviously natural CO2 can't cause climate change, right?:)
You get funnier every day!
The literature that you referenced does not support Spencer's claim that clouds are a negative feedback.
Let's be clear as to what Spencer claims - "But we have never claimed anything like “clouds are the cause of, and not a feedback on, changes in surface temperature”! We claim causation works in BOTH directions, not just one direction (feedback) as he claims."
The literature only shows that clouds are a large negative forcing.
Do you also accept that the literature of Ramanthan underestimated the negative forcing by a factor of 2?
This is not a novel claim as shown by Ramanathan 1989.
You'll have to be specific - *what* claim. Ramanthan is very careful not to claim anything other than the idea that measuring forcing from year to year can help answer some vexing questions. Speculation != claim.
This also does not imply that clouds are a large negative feedback as shown by Ramanathan 1989.
What? You need to make up your mind - is Ramanthan saying clouds are a *negative* feedback, or *positive* feedback in your opinion? Be precise!
In fact Ramanathan 1989 specifically states that BECAUSE clouds are a large negative forcing we may find that they are a significant positive feedback.
Read the article again - he makes a claim that they could play a significant feedback role, but he only *speculates* that this feedback is positive, not negative. From his abstract:
"Hence, small changes in the cloud-radiative forcing fields can play a significant role as a climate feedback mechanism."
Note the lack of "positive" or "negative" quantifier there before the word "feedback".
The literature that you referenced shows that clouds are a negative feedback
I'd say it strongly implies, and at the least brings into question whether or not they are purely a positive feedback. If I've confused you earlier I apologize, and hope you can understand my clarification.
A negative cloud forcing is inconsistent with the IPCC finding that clouds are a small positive feedback.
I'll be more specific - a net negative cloud forcing, along with the assertion that a warmer world produces more clouds (which would produce more negative cloud forcing), is inconsistent with the idea that clouds are a small positive feedback. Now, perhaps for the edge case of a drought stricken landscape there is reason to believe they could regionally be a small positive feedback, but certainly not on a global scale. The problem with the IPCC is that it is inconsistent with itself.
Ramanathans many examples of positive cloud feedbacks all go something like: "So more heat, means more moisture, means more clouds, which have a negative forcing, which means less negative forcing"
I've got nothing against Ramanthan's speculations (hard to call his imagination "examples") - my statement there is a parody of your position (and ap
Okay, so you don't believe that clouds are a positive feedback. Even less of a reason to believe that human CO2 is going to cause catastrophic warming on any timescale:)
WRONG! From the paper: "The positive cloud feedback mechanism implies that the size of the (negative) SW cloud forcing would decrease significantly"
Way to miss the context of the two previous sentences:
"In the Great Plains region of North America, the summer soil wetness in *one model* is decreased by 50 percent, which *suggests* that a positive feedback between clouds and land surface could be a factor in soil drying. An initial tendency for drying causes decreased cloudiness, which leads to increased solar heating of the soil, thus amplifying the tendency toward drying. The positive cloud feedback mechanism implies that the size of the (negative) SW cloud forcing would decrease significantly during a drought event."
So on top of being specific to less than 1/3rd of the earth's surface at most (remember, we're talking land temperature here), he's talking about a model that *suggests* an implication. A far cry from asserting it as either true, or even less so true for the entire globe:)
Clearly they are consistent.
Read your quote again.
"during past glaciations a migration toward the equator of the field of strong, negative cloud-radiative forcing, in response to a similar migration of cooler waters, *could have* significantly amplified oceanic cooling and continental glaciation.""
Note the "could have" - this is speculation. They *might* be consistent, but no such claim is being made.
In other words, he is suggesting that the "mythical" world (as you put it) is Earth.
Again, read your quote again:
"An initial tendency for drying causes decreased cloudiness, which leads to increased solar heating of the soil, thus amplifying tendency toward drying. "
The earth, as you know, is mostly covered in water - or do you know of some alternate "Earth" that only has soil on its surface?:)
WRONG! Ramanathan is comparing the total cloud forcing to only the anthropogenic portion of the carbon forcing. If he were to compare total cloud forcing to total CO2 forcing he would have stated that the cloud forcing is many times smaller than the CO2 forcing.
Okay, shall I just let you win this particular battle, so you lose the war?:) If the total CO2 forcing is mostly non-anthropogenic, then why would we worry about the insignificant anthropogenic portion?:)
That is me? WRONG! Way to slay that straw man!
Well, until you're able to put forth a falsifiable hypothesis statement you'll stand behind, I can only fill the empty suit you present me with straw:)
Well, get me some falsifiability, and then we'll see how I react:)
Go ahead, specify a combination of CO2 and temperature that would falsify your hypothesis - add whatever other variables you feel necessary if those two aren't sufficient.
Trust me, that postulation goes nothing like: "So more heat, means more moisture, means more clouds, which have a negative forcing, which means less negative forcing?" You are so far off it is laughable.
Clouds are a negative forcing. You seem to believe that clouds have a positive feedback, which means that as it gets hotter there would be less clouds (therefore less negative forcing). This is *your* postulation, not Ramanthan's.
See Ramanthan 1989 where he discusses negative cloud forcing and positive cloud feedback in the same paper. Clearly these are not inconsistent.
On the contrary, simply *discussing* them in the same paper does *not* make them consistent. You're again reading too much into Ramanthan.
Well Ramanthan says that cloud forcing is large and negative!
No, Ramanthan says that cloud forcing is negative, but he miscalculates by half compared to the latest research. He speculates that because it has such a big impact (even by his count, four times any effect CO2 could have), that *if* in some mythical world there was a feedback with temperature that somehow made clouds *less* negative (less clouds with more heat?), that you could note that by comparing various forcing calculations from year to year.
He also says that we may expect positive cloud feedback.
You haven't read the paper, have you? He makes no assertion of expectation (an in fact, uses the term "expect" and its derivatives only twice in the whole paper). Let's look at the paper again:
"For example, results from some GCMs *suggest* that severe drying of the mid-continental regions in North America and Europe could result from a doubling of CO2 concentrations...[one model] suggests that a positive feedback between clouds and land surface could be a factor in soil drying."
Ramanthan is doing science, putting forth the idea that by measuring cloud forcing we can test certain hypotheses (such as the idea of positive cloud "feedback"). He's not jumping off a cliff and saying "I've measured cloud forcing, and therefore we can expect positive cloud feedback" - that's all you baby:)
No, Ramanthan 1989 doesn't say that at all - *you* did. Let's review:
YOU: "If the negative forcing decreases with an increase of heat then you have a positive feedback."
ME: "So more heat, means more moisture, means more clouds, which have a negative forcing, which means less negative forcing?"
YOU: "Ramanthan didn't say that!"
Of course I paraphrase a bit there, but you get the gist. Ramanathan 1989 doesn't say what you think it says, because what you're trying to say *doesn't make sense* - all he's doing is *postulating* a *possible* positive feedback, he's not asserting it. From his paper:
"Cloud forcing data could verify this postulated positive cloud feedback. For example, this mechanism would imply that the summertime SW cloud forcing over the Great Plains was anomalously low during the 1988 drought. Comparison of the cloud forcing for this year with the forcing for other years should confirm or refute this suggestion."
Ramanthan is incredibly careful not to make any claims in his paper, but you don't seem to understand that.
Go ahead, read the chain again, and see if that helps!:)
Sure I read the paper. It just doesn't say what you think it says:)
The cloud forcing is preexisting. The forcing from doubling CO2 is new.
So are you claiming that never before in the history of the planet have we ever had 400ppm CO2? 800ppm CO2?
I guess "new" all depends on how selective your memory is:)
The interesting part about the cloud forcing is determining, over a range of temperatures, what the changes to that forcing is ("feedback" as you term it). It very well may be (as per recent research), that the forcing not only depends on temperature, but also on non-terrestrial/atmospheric influences, such as cosmic rays. Simply asserting that the cloud forcing depends only on temperature to determine its magnitude seems a bit silly, even for you:)
If the negative forcing decreases with an increase of heat then you have a positive feedback.
So more heat, means more moisture, means more clouds, which have a negative forcing, which means less negative forcing?
You keep using these terms "feedback" and "forcing" without really seeming to understand them. Maybe it's just that we're not being specific enough - after all, the idea of purely linear "feedback" on any of the myriad climate variables is more than unlikely. Maybe if instead of simply using the terms "negative" and "positive" to describe "feedback", you'd provide a graph for what you think the changes in temperature might do to a given forcing over a wide range of temperatures.
It seems to me that any rational observation of cloud effect on climate would show that they have a buffering effect, increasing in cooling when things get too hot, and decreasing in cooling when things get too cold. Certainly the relatively narrow band of historical climates indicate that (even including ice ages).
See Ramanthan 1989
"The size of the observed net cloud forcing is about four times as large as the expected value of radiative forcing from a doubling of CO2."
And yet somehow we're worried about CO2? Maybe the real problem we should be addressing is cloud formation!
He also seems to get a net cooling effect calculation less than recent studies have shown (about half of what my cite shows).
Watt's obviously doesn't know what a feedback is. (Do you?)
Apparently you know know what a feedback is either...or at least you can't come up with any falsifiable hypothesis for determining whether or not a given climate factor is a feedback or a forcing:)
From the paper cited:
"the cloud radiative cooling effect through reflection of short wave radiation is found to dominate over the long wave heating effect, resulting in a net cooling of the climate system of 21 Wm2."
Go ahead, explain how IPCC models that depend on clouds having a net heating of the climate system jive with this.
"The Partial Radiative Perturbation (PRP) method, that excludes clear-sky changes from the definition of cloud feedbacks, diagnoses a positive global net cloud feedback in virtually all the models (Colman, 2003a; Soden and Held, 2006). "
Imagine where we'd be if the first chemists said "we can't know anything until we know everything."
Imagine where we'd be if the first chemists said "fire, earth, air, water - the science is settled".:)
If you assume that water vapor, cloud and other effects are linearly dependent on CO2 levels in a narrow range of temperatures, then from modeling the past climate you can determine the climate sensitivity to CO2 without determining the size of each of the feedback mechanisms.
You can't assume that. You need to come up with a falsifiable hypothesis statement, and explicitly state what observations would falsify those assumptions. That's the way the science game is played.
Clouds also appear to be a small positive feedback rather than a negative feedback.
But when you talk about all these factors you seem to be thinking that water vapor, clouds, and temperature could suddenly change without cause.
Far from it, I understand that all of these things have changed due to natural causes the entire history before mankind existed, and understand that our default null hypothesis should be that those same natural causes are what drive current observed climate changes.
Large cloud formations not predicted by the model that cause cooling would be a failure of the model (not to mention unlikely) that, if stable decade to decade, would refute global warming.
You're not being precise. Global warming happens. It has happened in the past, and will certainly happen in the future, and even large cloud formations could be asserted as an ad hoc special pleading that preserves your original intent of "human CO2 is what caused warming in the 20th century". Whether or not any given period of global warming can be attributed to a specific factor is the question. The fact that you can't specify what your falsifiable hypothesis statement is means that any straw man put up (i.e., human CO2 is responsible for.01C/decade warming,.02C/decade warming, etc, etc) can be objected to. Do me the favor of being specific in your falsifiable hypothesis statement, and we can skip the part where I have to read your mind.
Of course, but there is no known factor that matches the profile of climate change other than CO2 increase.
That's an argument from ignorance - just because we don't have a specific explanation for you, doesn't mean that your explanation is the truth. Without specifying what your falsifiable hypothesis statement is, you've essentially created a hypothesis that can match *any* profile that is observed. This is a weakness in a hypothesis, not a strength.
"The most characteristic element in this situation seemed to me the incessant stream of confirmations, of observations which "verified" the theories in question; and this point was constantly emphasize by their adherents. A Marxist could not open a newspaper without finding on every page confirming evidence for his interpretation of history; not only in the news, but also in its presentation — which revealed the class bias of the paper — and especially of course what the paper did not say. The Freudian analysts emphasized that their theories were constantly verified by their "clinical observations." As for Adler, I was much impressed by a p
The hell you haven't. You can determine the relative importance of each forcing using a climate model that can reproduce the past temperature history.
BS. Atmospheric temperature, water vapor and clouds depend on more than just CO2. If you double CO2, and fail to account for all the other variables that have changed over the same period of time, you don't have anything.
The fit to prior climate tells you the temperature forcing of CO2 even if you don't understand the exact effect of increased CO2 on water vapor or cloud cover.
Hard coding a model does not make it true. Explaining every deviation of reality from a model as time moves on with an ad hoc special pleading shows a particular weakness of the model. The "our prediction for this year didn't come true because of [ENSO/PDO/Pinatubo/Chinese Aerosols]" is a denial of falsification, and therefore a denial of science.
Essentially what you are saying is scientists are idiots that don't understand linear algebra or principle component analysis.
Scientists who can't come up with a falsifiable hypothesis are idiots (or at least navel gazers). Linear algebra and principal component analysis have nothing to do with it.
As far as what would disprove anthropogenic global warming, right now I think the 95% no-confidence point is two solar cycles (i.e. 22 years) of flat or downward trending temperatures without causative a forcing (i.e. a caldera explosion with continued eruptions or something similar that cuts sunlight).
Sounds like you've built in a loop hole there - no matter what happens, you'll blame it on "something similar that cuts sunlight". Maybe it'll be Chinese Aerosols. Maybe it'll be unique cloud formations caused by atmospheric patterns in the southern hemisphere. Maybe it'll be an explosion of high-albedo butterflies in Brazil.
Can you accept the fact that your prediction, as stated, could also come true if a non-CO2 or other non-human factor that is currently unidentified has a net-warming effect?
From the stand point of trying to set policy, your position is ridiculous.
Let's make it clear, I'm here to play the science game, not the policy game. If the questions I'm asking are ridiculous for policy makers, it's because they're not interested in what the scientific method provides here.
"What is the proximate cause of the warming?"
Even with this question, the null hypothesis is "the same causes that have been in effect during other periods of warming before humanity existed". Those causes don't have to be specified, and moreover, are probably too numerous and chaotic to be specified in detail.
Now, you may ask separate sub questions, like "Are solar fluctuations the proximate cause of the current warming?" or "Are cosmic ray variations the proximate cause of the current warming?" or "Are GHG variations the proximate cause of the current warming?" - in each case, the null hypothesis is "current warming has the same causes as in effect during other periods of warming before humanity existed."
Thus far, the assumption that solar and cosmic radiation cannot account for 100% of the observed warming recently does not provide much support to the idea that human emitted GHGs do account for 100%, or 50%, or really any defined magnitude. After all, nature found a way to have rapid periods of warming in the past (and rapid periods of cooling in the past), without having to resort to human SUV emissions.
That all being said, if you're convinced that GHGs are the primary cause (>50%?), why do you suppose CO2 lags temperature changes in the ice core record?
You mean your confusion between the tilt of the earth *causing* seasons, and seasons being *defined* by the tilt of the earth WRT the sun?
Let's review - even if we have a "year without summer" in 1816 because of major volcanic eruptions, where seasonal differences are drastically modified by natural variation and the experience of "summer" is eliminated, it is still technically the season "summer" in the northern hemisphere when the north pole is tilted toward the sun.
Unless, of course, you want to blame 1816 on a dramatic variation in the tilt of the earth that year:)
There's tons of falsifiability, you just won't hear about it from them.
I beg to differ. From your article cite:
"In one sense, the Theory of Global Warming is clearly a falsifiable scientific theory: all we need to do is wait around a while until industrial activities have doubled CO2, and observe what has happened to atmospheric temperature, water vapor and clouds. This indeed seems to be the experiment that most of the world seems intent on carrying out."
Even if you double CO2, and observe what has happened to atmospheric temperature, water vapor and clouds, you haven't linked it to the CO2. There are myriad drivers of climate and you cannot simply say "wait until we get to 750ppm CO2, and that'll prove it". There's no prediction being made at all.
If you want to make the case that CAGW is falsifiable, make your falsifiable hypothesis statement. Exactly *what* CO2 and temperature combination would need to be observed in order to falsify it in 5 years? 10 years? 30 years? 100 years? If CO2 and temperature aren't sufficient for your hypothesis, feel free to add in other factors, but be specific.
Natural climate change is the null hypothesis. Climate has always changed in the past, long before humanity ever existed, so we can safely assume that *any* observed change before humanity existed had a non-human cause. Since climate was more than able to change in the past because of non-human causes, we start with the null hypothesis that says that any observation even after the rise of humanity can similarly be explained. It then becomes incumbent on the affirmative, who want to assert that climate after the rise of humanity, or after the industrial age, or whatever marker you choose, is controlled by humanity.
Now climate changes in pre-humanity times have had both statistically significant upward and downward trends, so the mere existence of a statistically significant trend doesn't serve to implicate humanity.
If you really want to play the science game, though, I invite you to make a clear falsifiable hypothesis statement, specifically identifying what observations would invalidate your hypothesis.
You pay more attention to me that most of my ex-girlfriends:)
Let's be clear here - I offered a falsifiable hypothesis of apples or other plants as a forcing versus a feedback. I didn't claim that it was not falsified, simply that, like all good science, you need to start with a falsifiable hypothesis statement.
Now, if you'd like to offer a better falsifiable hypothesis statement for deciding when a factor is a forcing or feedback on climate, I'd welcome it, but I'm not holding my breath:)
Agreement with what? That the climate warmed over the past century? That's one of the predicates to a statement of CAGW, but hardly a resounding endorsement.
Natural climate change happens and is our default null hypothesis here. What observations of data could convince you that observed climate change is not due to CO2, or not due to humans, or is not going to be catastrophic?
I'm more than willing to stipulate GGP was Correct Insightful Flamebait:)
My problem with the whole CAGW "science" is that it fails to start off with your basic falsifiable hypothesis, without which, playing the science game is pretty much impossible. NGW and AGW (natural global warming and anthropogenic global warming), when asserted simply in a given direction without magnitude, are almost trivially true (as well as falsifiable). Once you decide to place a magnitude on it, your falsifiable hypothesis statement gets even more important to have - typically, this is glossed over and we get nothing but ad hoc special pleadings for any observation contrary to models.
My big bitch is that Jeusuy McAnnRaynd is the last person in the world I'd ever expect to be busy out there *defending* the scientific method. It's like previously KKK Democrats taking credit for the civil rights movement.
Note that is has/already/ been shown significant potentially very dangerous changes will occur from human activity.
That sounds much too strong at the same time it includes the weasel word "potentially". Let's be more specific.
Has it been shown that significant changes will occur from human activity? As per our discussion before, that requires putting a specific magnitude on AGW, in order to allow it to be falsified. Thus far, "significant" has not been quantified as being "measurable" (in the strictly scientific sense of the term "significant"), or as being "very very large" (in the more colloquial sense of the term "significant").
Even if "significant" changes (in either sense of the word) are stipulated to, the definition of "dangerous" needs to be more specific. What beneficial changes are possible from "significant" changes? What harmful changes are possible from "significant" changes? By what measurement do we judge benefit and harm? What observations would falsify a hypothesis of more harm than benefit?
Quantumn mechanics standard model Evolution Genetic basis of behaviour Generative grammar General relativity
QM I already offered a cite for falsifiable predictions and falsification attempts between vying camps. Since QM is really a collection of theories, I can understand that one might say that the falsification I cited didn't apply to the entire mass of QM. However, unlike the components of climate that may live under "Climate Theory", CAGW in particular although concerned with climate, does not offer falsifiability like other hypotheses under the umbrella of "Climate Theory" (analogous to "Quantum Mechanics Theory" which has sub-hypotheses).
For evolution, you've got the rabbit in the pre-cambrian.
For the genetic basis of behavior, you're talking mostly pseudo-science. Epidemiological studies can show correlation, but not causality, and no significant work has been completed to even understand *how* the brain actually works for us to get to the point where we can hypothesize a causal relationship between DNA and an individual decision to behave a certain way. I've found that this kind of study is done mostly by racialists intent on showing that there are distinct sub-specie of human that can be categorized.
Generative grammar is also mostly pseudo-science (like Marx's theory of history or Astrology). While certainly interesting to study, and perhaps some sub-hypotheses may compete with each other for dominance, I'll argue that literally *any* of their hypotheses can be willfully falsified simply by inventing a new language that disobeys their proposed rules.
General relativity is the easiest - In his 1916 paper, Einstein said that the Sun's gravity would bend light. He predicted that a photograph taken during a solar eclipse would clearly show the effect. Starlight passing near the Sun would bend, and the stars would show up in just slightly the wrong place. If they didn't, then his theory would be falsified. Guess which happened?:)
We're talking about theories, not models.
Isn't that a distinction without a difference for CAGW?
Let's put it another way - there are competing "theories" of QM, or even the more fanciful string theory and supersymmetry. What are the competing "theories" of CAGW? Does one insist that CO2 has feedback mechanism A and another insist that CO2 has feedback mechanism B? From a purely technical point of view, differing GCMs obviously have different calculations to make their predictions - aren't these GCMs simply automated implementations of their theoretical underpinnings?
Insects evolved in equilibrium with flaura, and make part of a dynamic system that produces and consumes CO2 on an scale that is an order of magnitude beyond human activity.
There is no single (as you put it) formal CAGW formulation with a null hypothesis.
I would assume the null hypothesis would be "climate will continue to change as it always has (i.e., AGW is a minor factor compared to others) with no greater or less frequency of catastrophe for humankind". It would be incumbent on anyone proposing a truly scientific theory of CAGW to show a falsifiable hypothesis statement that would indict AGW as a primary driver of climate (rather than just one of many equals, or one of the minor ones), as well as quantify and predict "catastrophe" in specific values/timescales.
There is no such formal formulation for/any/ substantial scientific theory. I defy you to find a single example for a substantial theory.
DNA replication versus protein replication (as I noted above). Or the specifics of falsifying QM by parts. Of course, your word "substantial" sounds like a subjective term, which would perhaps disallow those examples because they didn't fit?
How about this, name 5 "substantial" theories, and we'll talk about what their formal falsifications are.
Think of symmetry: it is broken, then fixed (we find the neutrino), then broken again, etc. Today, most physicists believe that symmetry is probably true even though it is currently broken. Where's your single falsibility hypothesis there?
The interesting part about that kind of stuff is that we *do* end up falsifying specific models of physics, in pursuit of a true one. The problem with computerized climate models is that they are never considered falsified - they simply get more hard coded ad hoc assumptions. Now, this could be true for symmetry as well (one might look at all the math tweaks here and there and cry foul), but I'd assert that physics models (symmetry, QM, etc), for the most part, are making falsifiable predictions and being ruthlessly tested against them. We've got a bunch of competing models, and various groups doing their best to make predictions that can be falsified, and then failing to find that falsification.
GCMs, on the other hand, are proclaimed "consistent", even as they vary from each other across multiple axes. None of them represents a repudiation of another of them - a sure sign we're not really doing science.
As an example of what I would consider non-scientific navel-gazing typically viewed as "scientific" by laymen, that makes no falsifiable predictions, would be the whole "string theory" (which some would claim is falsifiable simply because it depends on QM as falsifiable - I reject that the same way I reject CAGW as being falsifiable simply because trivial AGW is falsifiable). Now, perhaps this will change one day, but while mathematical exercises may be fun and pretty, without falsifiability it's not really science.
btw, your coment about comparing the volume of insect CO2 emissions to burning fossil fuels is a good example of junk science. Can you think why?
The only caveat there is timescale, of course. Before insects existed, they didn't emit CO2. With the rise of insects, CO2 increased, and as per the theory of IGW we stipulate to, this CO2 must have some warming effect. How quickly did insects increase in population? No idea, but I could imagine a fairly exponential curve.
Now, "fossil fuel" burning by humans is considered to be on a quicker timescale (scare quotes because of abiogenic petroleum), but even then, we don't have very good data on say, the variation of burning methane/forests/volcanoes/other CO2 injections over time to assert that the planet hasn't seen the same kind of increase in CO2 in the past. In fact, from the ice core record, we can note that we *did* in fact see CO2 increases of this kind of rate/magnitude in the past, which would follow if temperature dramatically rose because of say, solar flux, causing the CO2 to outgas very quickly from the oceans, for example.
That all being said, can you think of why the trivial AGW hypothesis of any positive effect is just as junk as IGW?:)
As the air cools under your "50% increase in albedo" scenario more water vapor continues to condense out until the droplets get heavy enough to precipitate out of the atmosphere.
I'm not quite sure if that follows, but then again I'm not a cloud expert:) This is all terribly speculative of course, but I'm very interested in seeing how the next 30 years pans out for the solar activity/cosmic ray/cloud cover hypothesis that predicts cooling in general, and I'd bet that some of the biggest leaps forward in climate understanding for the next decade is going to be characterizing ocean currents and drivers like ENSO/PDO, etc.
I never proposed a "null hypothesis" because I'm interested in science, not statistics.
Perhaps you've forgotten this exchange:
ME: "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,"
YOU: "My hypothesis would be that each change of climate had a cause."
Did you not understand what the original question was?
We know that climate changes. We assume that all such changes have a cause.
Sure, we may not know the cause, but certainly the change had a cause. Trivial assertions.
Examining the data available to us appears to show that the largest cause of the current episode is an increase in atmospheric CO2.
Epic fail. You've got no basis for asserting that at all, and more importantly, no specification of what observed data would falsify your hypothesis. This means, you're not doing science.
After-all, according to some, we're about to head into a cooling phase for 30 years!
As a test of the solar/cosmic ray/cloud hypothesis, that seems like a reasonable, if risky position to hold. I'm probably more inclined at this moment, based on the evidence, to believe that is true. In 30 years, if solar activity slows, cosmic ray activity rises, cloud cover increases, and we *don't* go into a cooling phase, I'll obviously alter my position.
So we have to establish that first the world *is* warming (which some of your friends deny), and that humans play some role in that (which some of your friends deny).
We can stipulate the following:
1) the world has been warming in recent history 2) human CO2 plays some role in that 3) insect CO2 plays a bigger role in that 4) other natural variations play some role in that
I would assert 3 since insects account for 48 billion tons of CO2, as compared to 34 billion tons of CO2 for humans and farming activity, but I don't have incredibly robust references for that off the top of my head.
Even with those three stipulations (or a modified 3rd stipulation if you wish), that seems to be *necessary* to a theory of CAGW (or a more robust specification of AGW magnitude), but not sufficient.
While this is no doubt the case, it does not follow, therefore, that CAGW is unfalsifiable.
You're right, my complaint of ad hoc special pleading does not necessarily prove that CAGW is unfalsifiable. However, the lack of any falsifiable hypothesis statement of CAGW *does*. I welcome you to present one, as complex as it may be.
Forget the fact (for the moment), that there are people who ideologically hate lazzie-faire capitalism, or have other disabilities regarding entrenched world views. That is a/separate/ issue to whether CAGW is falsifiable or not. Agreed?
Absolutely. CAGW being falsifiable or not depends on the specific falsifiable hypothesis statement being presented. There may be dozens of CAGW strawmen that are not falsifiable, another few dozen CAGW strawmen that are both falsifiable and falsified, but I have not yet heard of a single CAGW formulation that is both falsifiable and not falsified.
AGW is true even if there is a small impact from CO2. It could mean that although there is warming, there is nothing to worry about in terms of risk management.
I believe we've hit consensus on the basics then - AGW (specifically due to CO2), as defined as *any* positive impact by CO2 is a falsifiable hypothesis, and I am willing to further stipulate that it is 100% true (not much of a stipulation since it includes the point of view that this positive impact is completely overwhelmed by non-anthropogenic forces, but there you have it).
Remember, AGW is a different hypothesis to CAGW. Both are falsifiable, although CAGW is orders of magnitude more complex, since one must make predictions on the magnitude of warming, and its consequences.
Now you jumped the shark. I will not accept that CAGW is falsifiable simply because AGW (with no claim of magnitude) is. My assertion is that proponents of CAGW will (and have) continually make ad hoc special pleadings when observations do not match their assertions.
By the same rationale that AGW is both falsifiable and 100% true, we could say that IGW (insect global warming) is both falsifiable and 100% true. But would you accept that because IGW is falsifiable, CIGW (catastrophic insect global warming) is as well?
We knew this for sure in 1979, according to the definitive NAS literature review of that year.
Was the NAS wrong about AGW?
What's the citation you're asking me to respond to? I'm not sure if the NAS asserted AGW in 1979 was simply guaranteed to be positive (no matter how small), or if they actually hung their hat on something less acceptable like it was guaranteed to be more than noise against background changes.
Anyway, so now that we've gotten to the basic agreement on what we mean by "AGW" when we say "AGW", would you like to move onto trying to show that CAGW is falsifiable? Or would you like to return to the discussion of specific QM and DNA predictions being falsifiable (and look for a citation of any other modern science which does not have any falsifiability)?
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Ah, the Layzej "Speculation Is Science" axiom. Got it :)
Of course not. Climate never changed before humans started releasing CO2, so obviously natural CO2 can't cause climate change, right? :)
You get funnier every day!
Let's be clear as to what Spencer claims - "But we have never claimed anything like “clouds are the cause of, and not a feedback on, changes in surface temperature”! We claim causation works in BOTH directions, not just one direction (feedback) as he claims."
http://www.drroyspencer.com/2011/09/the-good-the-bad-and-the-ugly-my-initial-comments-on-the-new-dessler-2011-study/
How's that straw man taking your beating? :)
Do you also accept that the literature of Ramanthan underestimated the negative forcing by a factor of 2?
You'll have to be specific - *what* claim. Ramanthan is very careful not to claim anything other than the idea that measuring forcing from year to year can help answer some vexing questions. Speculation != claim.
What? You need to make up your mind - is Ramanthan saying clouds are a *negative* feedback, or *positive* feedback in your opinion? Be precise!
Read the article again - he makes a claim that they could play a significant feedback role, but he only *speculates* that this feedback is positive, not negative. From his abstract:
"Hence, small changes in the cloud-radiative forcing fields can play a significant role as a climate feedback mechanism."
Note the lack of "positive" or "negative" quantifier there before the word "feedback".
I'd say it strongly implies, and at the least brings into question whether or not they are purely a positive feedback. If I've confused you earlier I apologize, and hope you can understand my clarification.
I'll be more specific - a net negative cloud forcing, along with the assertion that a warmer world produces more clouds (which would produce more negative cloud forcing), is inconsistent with the idea that clouds are a small positive feedback. Now, perhaps for the edge case of a drought stricken landscape there is reason to believe they could regionally be a small positive feedback, but certainly not on a global scale. The problem with the IPCC is that it is inconsistent with itself.
I've got nothing against Ramanthan's speculations (hard to call his imagination "examples") - my statement there is a parody of your position (and ap
Okay, so you don't believe that clouds are a positive feedback. Even less of a reason to believe that human CO2 is going to cause catastrophic warming on any timescale :)
Way to miss the context of the two previous sentences:
"In the Great Plains region of North America, the summer soil wetness in *one model* is decreased by 50 percent, which *suggests* that a positive feedback between clouds and land surface could be a factor in soil drying. An initial tendency for drying causes decreased cloudiness, which leads to increased solar heating of the soil, thus amplifying the tendency toward drying. The positive cloud feedback mechanism implies that the size of the (negative) SW cloud forcing would decrease significantly during a drought event."
So on top of being specific to less than 1/3rd of the earth's surface at most (remember, we're talking land temperature here), he's talking about a model that *suggests* an implication. A far cry from asserting it as either true, or even less so true for the entire globe :)
Read your quote again.
"during past glaciations a migration toward the equator of the field of strong, negative cloud-radiative forcing, in response to a similar migration of cooler waters, *could have* significantly amplified oceanic cooling and continental glaciation.""
Note the "could have" - this is speculation. They *might* be consistent, but no such claim is being made.
Again, read your quote again:
"An initial tendency for drying causes decreased cloudiness, which leads to increased solar heating of the soil, thus amplifying tendency toward drying. "
The earth, as you know, is mostly covered in water - or do you know of some alternate "Earth" that only has soil on its surface? :)
Okay, shall I just let you win this particular battle, so you lose the war? :) If the total CO2 forcing is mostly non-anthropogenic, then why would we worry about the insignificant anthropogenic portion? :)
Well, until you're able to put forth a falsifiable hypothesis statement you'll stand behind, I can only fill the empty suit you present me with straw :)
Keep trying!
Well, get me some falsifiability, and then we'll see how I react :)
Go ahead, specify a combination of CO2 and temperature that would falsify your hypothesis - add whatever other variables you feel necessary if those two aren't sufficient.
Clouds are a negative forcing. You seem to believe that clouds have a positive feedback, which means that as it gets hotter there would be less clouds (therefore less negative forcing). This is *your* postulation, not Ramanthan's.
On the contrary, simply *discussing* them in the same paper does *not* make them consistent. You're again reading too much into Ramanthan.
No, Ramanthan says that cloud forcing is negative, but he miscalculates by half compared to the latest research. He speculates that because it has such a big impact (even by his count, four times any effect CO2 could have), that *if* in some mythical world there was a feedback with temperature that somehow made clouds *less* negative (less clouds with more heat?), that you could note that by comparing various forcing calculations from year to year.
You haven't read the paper, have you? He makes no assertion of expectation (an in fact, uses the term "expect" and its derivatives only twice in the whole paper). Let's look at the paper again:
"For example, results from some GCMs *suggest* that severe drying of the mid-continental regions in North America and Europe could result from a doubling of CO2 concentrations...[one model] suggests that a positive feedback between clouds and land surface could be a factor in soil drying."
Ramanthan is doing science, putting forth the idea that by measuring cloud forcing we can test certain hypotheses (such as the idea of positive cloud "feedback"). He's not jumping off a cliff and saying "I've measured cloud forcing, and therefore we can expect positive cloud feedback" - that's all you baby :)
No, Ramanthan 1989 doesn't say that at all - *you* did. Let's review:
YOU: "If the negative forcing decreases with an increase of heat then you have a positive feedback."
ME: "So more heat, means more moisture, means more clouds, which have a negative forcing, which means less negative forcing?"
YOU: "Ramanthan didn't say that!"
Of course I paraphrase a bit there, but you get the gist. Ramanathan 1989 doesn't say what you think it says, because what you're trying to say *doesn't make sense* - all he's doing is *postulating* a *possible* positive feedback, he's not asserting it. From his paper:
"Cloud forcing data could verify this postulated positive cloud feedback. For example, this mechanism would imply that the summertime SW cloud forcing over the Great Plains was anomalously low during the 1988 drought. Comparison of the cloud forcing for this year with the forcing for other years should confirm or refute this suggestion."
Ramanthan is incredibly careful not to make any claims in his paper, but you don't seem to understand that.
Go ahead, read the chain again, and see if that helps! :)
Sure I read the paper. It just doesn't say what you think it says :)
So are you claiming that never before in the history of the planet have we ever had 400ppm CO2? 800ppm CO2?
I guess "new" all depends on how selective your memory is :)
The interesting part about the cloud forcing is determining, over a range of temperatures, what the changes to that forcing is ("feedback" as you term it). It very well may be (as per recent research), that the forcing not only depends on temperature, but also on non-terrestrial/atmospheric influences, such as cosmic rays. Simply asserting that the cloud forcing depends only on temperature to determine its magnitude seems a bit silly, even for you :)
So more heat, means more moisture, means more clouds, which have a negative forcing, which means less negative forcing?
You keep using these terms "feedback" and "forcing" without really seeming to understand them. Maybe it's just that we're not being specific enough - after all, the idea of purely linear "feedback" on any of the myriad climate variables is more than unlikely. Maybe if instead of simply using the terms "negative" and "positive" to describe "feedback", you'd provide a graph for what you think the changes in temperature might do to a given forcing over a wide range of temperatures.
It seems to me that any rational observation of cloud effect on climate would show that they have a buffering effect, increasing in cooling when things get too hot, and decreasing in cooling when things get too cold. Certainly the relatively narrow band of historical climates indicate that (even including ice ages).
"The size of the observed net cloud forcing is about four times as large as the expected value of radiative forcing from a doubling of CO2."
And yet somehow we're worried about CO2? Maybe the real problem we should be addressing is cloud formation!
He also seems to get a net cooling effect calculation less than recent studies have shown (about half of what my cite shows).
So a net *cooling* from clouds of 21 W/m2 is somehow compatible with the idea that clouds are a *positive* feedback?
Really?
Keep digging, friend :)
Apparently you know know what a feedback is either...or at least you can't come up with any falsifiable hypothesis for determining whether or not a given climate factor is a feedback or a forcing :)
From the paper cited:
"the cloud radiative cooling effect through reflection of short wave radiation is found
to dominate over the long wave heating effect, resulting in a net cooling of the climate system of 21 Wm2."
Go ahead, explain how IPCC models that depend on clouds having a net heating of the climate system jive with this.
http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch8s8-6-3-2.html
"The Partial Radiative Perturbation (PRP) method, that excludes clear-sky changes from the definition of cloud feedbacks, diagnoses a positive global net cloud feedback in virtually all the models (Colman, 2003a; Soden and Held, 2006). "
Imagine where we'd be if the first chemists said "fire, earth, air, water - the science is settled". :)
You can't assume that. You need to come up with a falsifiable hypothesis statement, and explicitly state what observations would falsify those assumptions. That's the way the science game is played.
Not according to the latest research: http://wattsupwiththat.com/2011/09/20/new-peer-reviewed-paper-clouds-have-large-negative-feedback-cooling-effect-on-earths-radiation-budget/
Far from it, I understand that all of these things have changed due to natural causes the entire history before mankind existed, and understand that our default null hypothesis should be that those same natural causes are what drive current observed climate changes.
You're not being precise. Global warming happens. It has happened in the past, and will certainly happen in the future, and even large cloud formations could be asserted as an ad hoc special pleading that preserves your original intent of "human CO2 is what caused warming in the 20th century". Whether or not any given period of global warming can be attributed to a specific factor is the question. The fact that you can't specify what your falsifiable hypothesis statement is means that any straw man put up (i.e., human CO2 is responsible for .01C/decade warming, .02C/decade warming, etc, etc) can be objected to. Do me the favor of being specific in your falsifiable hypothesis statement, and we can skip the part where I have to read your mind.
That's an argument from ignorance - just because we don't have a specific explanation for you, doesn't mean that your explanation is the truth. Without specifying what your falsifiable hypothesis statement is, you've essentially created a hypothesis that can match *any* profile that is observed. This is a weakness in a hypothesis, not a strength.
Obligatory Popper cite: http://www.stephenjaygould.org/ctrl/popper_falsification.html
"The most characteristic element in this situation seemed to me the incessant stream of confirmations, of observations which "verified" the theories in question; and this point was constantly emphasize by their adherents. A Marxist could not open a newspaper without finding on every page confirming evidence for his interpretation of history; not only in the news, but also in its presentation — which revealed the class bias of the paper — and especially of course what the paper did not say. The Freudian analysts emphasized that their theories were constantly verified by their "clinical observations." As for Adler, I was much impressed by a p
BS. Atmospheric temperature, water vapor and clouds depend on more than just CO2. If you double CO2, and fail to account for all the other variables that have changed over the same period of time, you don't have anything.
Hard coding a model does not make it true. Explaining every deviation of reality from a model as time moves on with an ad hoc special pleading shows a particular weakness of the model. The "our prediction for this year didn't come true because of [ENSO/PDO/Pinatubo/Chinese Aerosols]" is a denial of falsification, and therefore a denial of science.
Scientists who can't come up with a falsifiable hypothesis are idiots (or at least navel gazers). Linear algebra and principal component analysis have nothing to do with it.
Sounds like you've built in a loop hole there - no matter what happens, you'll blame it on "something similar that cuts sunlight". Maybe it'll be Chinese Aerosols. Maybe it'll be unique cloud formations caused by atmospheric patterns in the southern hemisphere. Maybe it'll be an explosion of high-albedo butterflies in Brazil.
Can you accept the fact that your prediction, as stated, could also come true if a non-CO2 or other non-human factor that is currently unidentified has a net-warming effect?
Let's make it clear, I'm here to play the science game, not the policy game. If the questions I'm asking are ridiculous for policy makers, it's because they're not interested in what the scientific method provides here.
Even with this question, the null hypothesis is "the same causes that have been in effect during other periods of warming before humanity existed". Those causes don't have to be specified, and moreover, are probably too numerous and chaotic to be specified in detail.
Now, you may ask separate sub questions, like "Are solar fluctuations the proximate cause of the current warming?" or "Are cosmic ray variations the proximate cause of the current warming?" or "Are GHG variations the proximate cause of the current warming?" - in each case, the null hypothesis is "current warming has the same causes as in effect during other periods of warming before humanity existed."
Thus far, the assumption that solar and cosmic radiation cannot account for 100% of the observed warming recently does not provide much support to the idea that human emitted GHGs do account for 100%, or 50%, or really any defined magnitude. After all, nature found a way to have rapid periods of warming in the past (and rapid periods of cooling in the past), without having to resort to human SUV emissions.
That all being said, if you're convinced that GHGs are the primary cause (>50%?), why do you suppose CO2 lags temperature changes in the ice core record?
You mean your confusion between the tilt of the earth *causing* seasons, and seasons being *defined* by the tilt of the earth WRT the sun?
Let's review - even if we have a "year without summer" in 1816 because of major volcanic eruptions, where seasonal differences are drastically modified by natural variation and the experience of "summer" is eliminated, it is still technically the season "summer" in the northern hemisphere when the north pole is tilted toward the sun.
Unless, of course, you want to blame 1816 on a dramatic variation in the tilt of the earth that year :)
I beg to differ. From your article cite:
"In one sense, the Theory of Global Warming is clearly a falsifiable scientific theory: all we need to do is wait around a while until industrial activities have doubled CO2, and observe what has happened to atmospheric temperature, water vapor and clouds. This indeed seems to be the experiment that most of the world seems intent on carrying out."
Even if you double CO2, and observe what has happened to atmospheric temperature, water vapor and clouds, you haven't linked it to the CO2. There are myriad drivers of climate and you cannot simply say "wait until we get to 750ppm CO2, and that'll prove it". There's no prediction being made at all.
Obligatory Popper cite: http://www.stephenjaygould.org/ctrl/popper_falsification.html
If you want to make the case that CAGW is falsifiable, make your falsifiable hypothesis statement. Exactly *what* CO2 and temperature combination would need to be observed in order to falsify it in 5 years? 10 years? 30 years? 100 years? If CO2 and temperature aren't sufficient for your hypothesis, feel free to add in other factors, but be specific.
Natural climate change is the null hypothesis. Climate has always changed in the past, long before humanity ever existed, so we can safely assume that *any* observed change before humanity existed had a non-human cause. Since climate was more than able to change in the past because of non-human causes, we start with the null hypothesis that says that any observation even after the rise of humanity can similarly be explained. It then becomes incumbent on the affirmative, who want to assert that climate after the rise of humanity, or after the industrial age, or whatever marker you choose, is controlled by humanity.
Now climate changes in pre-humanity times have had both statistically significant upward and downward trends, so the mere existence of a statistically significant trend doesn't serve to implicate humanity.
If you really want to play the science game, though, I invite you to make a clear falsifiable hypothesis statement, specifically identifying what observations would invalidate your hypothesis.
Ah! My Friendly Neighborhood Slashdot Stalker!
You pay more attention to me that most of my ex-girlfriends :)
Let's be clear here - I offered a falsifiable hypothesis of apples or other plants as a forcing versus a feedback. I didn't claim that it was not falsified, simply that, like all good science, you need to start with a falsifiable hypothesis statement.
Now, if you'd like to offer a better falsifiable hypothesis statement for deciding when a factor is a forcing or feedback on climate, I'd welcome it, but I'm not holding my breath :)
Agreement with what? That the climate warmed over the past century? That's one of the predicates to a statement of CAGW, but hardly a resounding endorsement.
Natural climate change happens and is our default null hypothesis here. What observations of data could convince you that observed climate change is not due to CO2, or not due to humans, or is not going to be catastrophic?
I'm more than willing to stipulate GGP was Correct Insightful Flamebait :)
My problem with the whole CAGW "science" is that it fails to start off with your basic falsifiable hypothesis, without which, playing the science game is pretty much impossible. NGW and AGW (natural global warming and anthropogenic global warming), when asserted simply in a given direction without magnitude, are almost trivially true (as well as falsifiable). Once you decide to place a magnitude on it, your falsifiable hypothesis statement gets even more important to have - typically, this is glossed over and we get nothing but ad hoc special pleadings for any observation contrary to models.
Parent is definitely Insightful Flamebait.
My big bitch is that Jeusuy McAnnRaynd is the last person in the world I'd ever expect to be busy out there *defending* the scientific method. It's like previously KKK Democrats taking credit for the civil rights movement.
It is indeed a cold day in hell.
That sounds much too strong at the same time it includes the weasel word "potentially". Let's be more specific.
Has it been shown that significant changes will occur from human activity? As per our discussion before, that requires putting a specific magnitude on AGW, in order to allow it to be falsified. Thus far, "significant" has not been quantified as being "measurable" (in the strictly scientific sense of the term "significant"), or as being "very very large" (in the more colloquial sense of the term "significant").
Even if "significant" changes (in either sense of the word) are stipulated to, the definition of "dangerous" needs to be more specific. What beneficial changes are possible from "significant" changes? What harmful changes are possible from "significant" changes? By what measurement do we judge benefit and harm? What observations would falsify a hypothesis of more harm than benefit?
QM I already offered a cite for falsifiable predictions and falsification attempts between vying camps. Since QM is really a collection of theories, I can understand that one might say that the falsification I cited didn't apply to the entire mass of QM. However, unlike the components of climate that may live under "Climate Theory", CAGW in particular although concerned with climate, does not offer falsifiability like other hypotheses under the umbrella of "Climate Theory" (analogous to "Quantum Mechanics Theory" which has sub-hypotheses).
For evolution, you've got the rabbit in the pre-cambrian.
For the genetic basis of behavior, you're talking mostly pseudo-science. Epidemiological studies can show correlation, but not causality, and no significant work has been completed to even understand *how* the brain actually works for us to get to the point where we can hypothesize a causal relationship between DNA and an individual decision to behave a certain way. I've found that this kind of study is done mostly by racialists intent on showing that there are distinct sub-specie of human that can be categorized.
Generative grammar is also mostly pseudo-science (like Marx's theory of history or Astrology). While certainly interesting to study, and perhaps some sub-hypotheses may compete with each other for dominance, I'll argue that literally *any* of their hypotheses can be willfully falsified simply by inventing a new language that disobeys their proposed rules.
General relativity is the easiest - In his 1916 paper, Einstein said that the Sun's gravity would bend light. He predicted that a photograph taken during a solar eclipse would clearly show the effect. Starlight passing near the Sun would bend, and the stars would show up in just slightly the wrong place. If they didn't, then his theory would be falsified. Guess which happened? :)
Isn't that a distinction without a difference for CAGW?
Let's put it another way - there are competing "theories" of QM, or even the more fanciful string theory and supersymmetry. What are the competing "theories" of CAGW? Does one insist that CO2 has feedback mechanism A and another insist that CO2 has feedback mechanism B? From a purely technical point of view, differing GCMs obviously have different calculations to make their predictions - aren't these GCMs simply automated implementations of their theoretical underpinnings?
Equilibrium? Isn't that a bold assertion to mak
I would assume the null hypothesis would be "climate will continue to change as it always has (i.e., AGW is a minor factor compared to others) with no greater or less frequency of catastrophe for humankind". It would be incumbent on anyone proposing a truly scientific theory of CAGW to show a falsifiable hypothesis statement that would indict AGW as a primary driver of climate (rather than just one of many equals, or one of the minor ones), as well as quantify and predict "catastrophe" in specific values/timescales.
DNA replication versus protein replication (as I noted above). Or the specifics of falsifying QM by parts. Of course, your word "substantial" sounds like a subjective term, which would perhaps disallow those examples because they didn't fit?
How about this, name 5 "substantial" theories, and we'll talk about what their formal falsifications are.
The interesting part about that kind of stuff is that we *do* end up falsifying specific models of physics, in pursuit of a true one. The problem with computerized climate models is that they are never considered falsified - they simply get more hard coded ad hoc assumptions. Now, this could be true for symmetry as well (one might look at all the math tweaks here and there and cry foul), but I'd assert that physics models (symmetry, QM, etc), for the most part, are making falsifiable predictions and being ruthlessly tested against them. We've got a bunch of competing models, and various groups doing their best to make predictions that can be falsified, and then failing to find that falsification.
GCMs, on the other hand, are proclaimed "consistent", even as they vary from each other across multiple axes. None of them represents a repudiation of another of them - a sure sign we're not really doing science.
As an example of what I would consider non-scientific navel-gazing typically viewed as "scientific" by laymen, that makes no falsifiable predictions, would be the whole "string theory" (which some would claim is falsifiable simply because it depends on QM as falsifiable - I reject that the same way I reject CAGW as being falsifiable simply because trivial AGW is falsifiable). Now, perhaps this will change one day, but while mathematical exercises may be fun and pretty, without falsifiability it's not really science.
The only caveat there is timescale, of course. Before insects existed, they didn't emit CO2. With the rise of insects, CO2 increased, and as per the theory of IGW we stipulate to, this CO2 must have some warming effect. How quickly did insects increase in population? No idea, but I could imagine a fairly exponential curve.
Now, "fossil fuel" burning by humans is considered to be on a quicker timescale (scare quotes because of abiogenic petroleum), but even then, we don't have very good data on say, the variation of burning methane/forests/volcanoes/other CO2 injections over time to assert that the planet hasn't seen the same kind of increase in CO2 in the past. In fact, from the ice core record, we can note that we *did* in fact see CO2 increases of this kind of rate/magnitude in the past, which would follow if temperature dramatically rose because of say, solar flux, causing the CO2 to outgas very quickly from the oceans, for example.
That all being said, can you think of why the trivial AGW hypothesis of any positive effect is just as junk as IGW? :)
I'm not quite sure if that follows, but then again I'm not a cloud expert :) This is all terribly speculative of course, but I'm very interested in seeing how the next 30 years pans out for the solar activity/cosmic ray/cloud cover hypothesis that predicts cooling in general, and I'd bet that some of the biggest leaps forward in climate understanding for the next decade is going to be characterizing ocean currents and drivers like ENSO/PDO, etc.
Thanks again for the enjoyable chat, riverrat!
Perhaps you've forgotten this exchange:
ME: "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,"
YOU: "My hypothesis would be that each change of climate had a cause."
Did you not understand what the original question was?
Sure, we may not know the cause, but certainly the change had a cause. Trivial assertions.
Epic fail. You've got no basis for asserting that at all, and more importantly, no specification of what observed data would falsify your hypothesis. This means, you're not doing science.
That's it. :)
As a test of the solar/cosmic ray/cloud hypothesis, that seems like a reasonable, if risky position to hold. I'm probably more inclined at this moment, based on the evidence, to believe that is true. In 30 years, if solar activity slows, cosmic ray activity rises, cloud cover increases, and we *don't* go into a cooling phase, I'll obviously alter my position.
We can stipulate the following:
1) the world has been warming in recent history
2) human CO2 plays some role in that
3) insect CO2 plays a bigger role in that
4) other natural variations play some role in that
I would assert 3 since insects account for 48 billion tons of CO2, as compared to 34 billion tons of CO2 for humans and farming activity, but I don't have incredibly robust references for that off the top of my head.
Even with those three stipulations (or a modified 3rd stipulation if you wish), that seems to be *necessary* to a theory of CAGW (or a more robust specification of AGW magnitude), but not sufficient.
You're right, my complaint of ad hoc special pleading does not necessarily prove that CAGW is unfalsifiable. However, the lack of any falsifiable hypothesis statement of CAGW *does*. I welcome you to present one, as complex as it may be.
Absolutely. CAGW being falsifiable or not depends on the specific falsifiable hypothesis statement being presented. There may be dozens of CAGW strawmen that are not falsifiable, another few dozen CAGW strawmen that are both falsifiable and falsified, but I have not yet heard of a single CAGW formulation that is both falsifiable and not falsified.
I believe we've hit consensus on the basics then - AGW (specifically due to CO2), as defined as *any* positive impact by CO2 is a falsifiable hypothesis, and I am willing to further stipulate that it is 100% true (not much of a stipulation since it includes the point of view that this positive impact is completely overwhelmed by non-anthropogenic forces, but there you have it).
Now you jumped the shark. I will not accept that CAGW is falsifiable simply because AGW (with no claim of magnitude) is. My assertion is that proponents of CAGW will (and have) continually make ad hoc special pleadings when observations do not match their assertions.
By the same rationale that AGW is both falsifiable and 100% true, we could say that IGW (insect global warming) is both falsifiable and 100% true. But would you accept that because IGW is falsifiable, CIGW (catastrophic insect global warming) is as well?
What's the citation you're asking me to respond to? I'm not sure if the NAS asserted AGW in 1979 was simply guaranteed to be positive (no matter how small), or if they actually hung their hat on something less acceptable like it was guaranteed to be more than noise against background changes.
Anyway, so now that we've gotten to the basic agreement on what we mean by "AGW" when we say "AGW", would you like to move onto trying to show that CAGW is falsifiable? Or would you like to return to the discussion of specific QM and DNA predictions being falsifiable (and look for a citation of any other modern science which does not have any falsifiability)?