Please, you are the expert on isolated exceptions.
And I was talking about opinions, when your opinions are disrespected by people from the right that are aware of the science, that leads me to the opinion that once again we can just declare you an ignorant with baseless allegations.
And again you missed that if I had seen it and was aware of the actual state of the science during the 70’s I would had kicked those “lefties” in the nuts. Once again: Most scientists said warming was coming in the 70’s, even if the thermometer was saying that for almost 20 years the temperature was dropping.
Far from being the “left” press one should consider one possible opinion: That the corporate press from the day would like to make the oil advertisers happy by telling most readers on the popular press that cooling was coming so we should not worry about the increase of GHGs and ignore what most of the scientists actually were saying.
But let’s drop any possibly collusion with major advertisers, (There is a very (un)funny double page ad saying that “Enco could melt this glacier with all the energy we make” from 1962)
Again, Peter Hadfield, the science reporter, explains better how silly or misleading the sources of the denier media are, first with the “there has been no warming in the last 10 or so years”:
And yes, religion is actually the item pointed at by Senator Inhofe (R, undead) as the reason to dismiss the climate scientists.
But the data doesn’t in fact show “a decade of apparent global cooling”.
What the long-term temperature charts show is an overall net rise in global temperature over the last few decades (although with lots of fluctuations up and down in the meanwhile), with a huge spike to a peak in the El Nino year of 1998 and a sharp drop back down to the pre-spike level in 1999, after which the overall fluctuating but rising trend continues until the 2010 level is nearly as high as the 1998 spike.
I don’t see how you can call that “cooling” in any meaningful sense: it’s just a continuation of a long-term overall warming trend with a big short-term spike in it.
A more accurate analogy with a weight-gain situation would be the case of, say, a 60-year-old woman who used to weigh 100 pounds back when she was fit and slim in 1970. Then she started increasing her average calorie intake without increasing her exercise rate and she’s been gaining, say, about one pound a year on average since then, although in the short term her weight has always fluctuated up and down.
In 1998 she ballooned up by 8 or 10 pounds but managed to lose that amount in 1999, since when her weight on average has been increasing at about the same rate as before. So she’s now about 40 pounds heavier than she was at her fit weight 40 years ago.
Any rational doctor would look at this woman’s weight record and conclude that yes, she definitely seems to have a long-term pattern of weight gain. The fact that her recent weight increases haven’t yet pushed her above her peak weight from the sudden spike in 1998 doesn’t mean that the overall upward trend isn’t there. Trying to tell this woman that her record doesn’t indicate a long-term weight-gain problem would be misleading and dishonest.
Actually, SA, you don’t recall correctly (as a brief glance at the earlier posts in this thread would have informed you, saving you from having to rely on your faulty recall). In fact, Sam said that he is convinced that the preponderance of the scientific evidence does support the AGW hypothesis:
Of course, Sam doesn’t believe that the AGW hypothesis is conclusively proven, but then, nobody else with any intelligence does either. What sensible people, including Sam, recognize about the AGW hypothesis (imperfect and incomplete though it admittedly still is) is that it’s currently by far the most successful scientific explanation we have to account for the existing evidence about global climate.
In other words, if you want some support for your flaccid bleatings about “oh well, maybe there’s warming and maybe there isn’t, there’s no telling one way or the other, so there’s no valid justification for accepting one view over the opposite view”, you ain’t getting it from Sam.
Well, the “left vs. right issue” is clearly the only aspect of the global warming issue you care about or know anything substantive about, and you clearly consider “personal politics” to be the determining factor in most other people’s views of the issue, even those of the scientists who are doing research on it. So I kind of doubt your boast that your own views on the subject are or will be determined by your making up your mind independently.
Judging from your track record on other policy issues requiring an informed opinion, if you ever do change your mind about global warming, it seems highly unlikely that you’ll know anything more then about the science involved than you know about it now. If it were actually important to you to educate yourself on the facts about the study of global climate and make up your own mind about the AGW hypothesis based on the facts, you’d have done it already.
I know I’ve seen reports that 2010 has been the warmest year on record. And I think it was 2005 that it had beaten. Is there some discrepancy between different sets of data where some still have 1998 as the warmest year? Or is there something else going on here?
The US (namely, the NCDC and NASA) reported that '99 was cooler than '98; the UN (namely, the WMO) later agreed. And so it went for '00, and '01, and '02, and '03, and '04. The US reported that '05 was a fraction of a degree warmer than '98; the UN later weighed in to disagree, saying that, no, it was still down from '98. The US then reported that '06 was below the '98 level, and the UN unsurprisingly agreed; so it went for '07 and '08 and '09. The US has now reported that '10 was a fraction of a degree warmer than '98; the UN hasn’t yet weighed in.
In other words, there was a general trend toward rising temperature punctuated by an especially high temperature spike in 1998, apparently due to El Nino effects. The temperature dropped sharply from that spike level in 1999 (as we would expect if the 1998 sharp rise was mostly due to a short-term event), and the overall rising trend, with fluctuations, continued.
Now the overall rising trend has brought the average temperature back up to about the 1998 spike level.
As I said, there’s no sensible way to interpret that as a long-term “cooling trend” of any kind. What it clearly appears to be is a warming trend with a high spike in it, surrounded by continual smaller fluctuations.
Recently I saw a TV program on the Little Ice Age (occurring during the 16th-19th centuries). The show discussed the different theories as to why the cooling occurred, and later presented several climate experts theorizing as to why the Little Ice Age came to an end.
After one expert talked about the possibility that a change in ocean currents caused a rebound to more “normal” temperatures in the 19th century, another was interviewed. This guy stated flat out that the warming was man-made and due to industrialization. He said this in a tone (and with a belligerent smirk) that brooked no dissent.
It’s people like that who concern me. When you’re perceived as being an utter zealot for your cause, distrust is fostered.
Note that I concur with the weight of expert opinion that recent warming has a marked man-made component and support prudent efforts to mitigate its effects.
And, again, that’s why I want to put primary emphasis on what hypothetical evidence could falsify the assorted predictions; I’m mildly interested in a declaration that twelve years isn’t enough, but I’m more interested in what would be enough.
The basic problem is that the past predictions of most scientists are happening. The earth is warming even if one just concentrates on the temperature over ground.
As Latif reminds us, variability was and will continue to be misinterpreted, either by ignorance or malice by the deniers.
So as for predictions, I still see that no matter if educated estimates were mentioned before, the fact is that you do not like the answers, as I learn more about this my estimations also change, only guys without a clue would expect that one could remain static or ignore reading and learning more. I still have to say that so far we have an “apparent” no increase of **surface **heat. Once again, this is to be expected when natural forcings are taken into account, what we could see is ten years more of this. Unfortunately it is not only the surface temperature that is increasing, the ocean temperature is currently where most of the heat is going and that does not show anything of the “cooling” that deniers are trying to use now to confuse people.
So a prediction is more complicated than before, I would still go for the next 10 years to show ups and downs, but once again, the trend will show warming by taking the previous decade into account, one stills needs almost 20 years to get a significant lowering temperature trend of the global surface temperature that would begin to throw justifiable doubts on the AGW theory, but it would not be good enough as it does not include the big picture, because the oceans are clearly ignoring the say so’s of the deniers.
The point is that the data from the past twelve years isn’t contradicting the “assorted predictions”, so it isn’t relevant to the falsification issue. An isolated spike doesn’t “falsify” a general trend.
Your basic problem seems to be that you don’t quite understand the difference between the concepts of a spike in a general pattern of data, and a reversal of a general pattern. Here’s a simple example:
Wow, you – cut the rest of the quote, which asked the question I now have to repeat. That’s actually sort of impressive.
I wrote: “I’m mildly interested in a declaration that twelve years isn’t enough, but I’m more interested in what would be enough.” You posted the first half of the sentence solely to take issue with it; I’ll now ask you to address the second half, which is the part I’m explicitly more interested in.
Er, no; I mentioned the part about the last twelve years not being enough to emphasize that I want to hear just how much would be enough. As per the sentence you half-quoted, I’m already perfectly willing to grant that a dozen years aren’t enough – and merely ask that you follow up by declaring what would be enough.
That’s fine in general terms, but I want to be sure we’re on the same page with regard to specifics: just how cold does it need to get, for just how long, to falsify the whole thing?
I mean, take a look at GIGO’s latest:
See? That’s a lot of wiggle room; instead of committing on falsifiability, GIGO is merely spelling out what doesn’t count. If the next ten years remain well under the '98 mark, if we get almost 20 years of significant lowering temperature, then it still wouldn’t be good enough for GIGO – and, again, that’s fine by me so long as GIGO then spells out what would be good enough.
(Take a really long look at GIGO’s whole post, there: on and on and on about how the apparent lack of increase in surface heat isn’t enough, about how I don’t like the answers so far, about changing estimations and natural forcing – but when it comes to spelling out what’s enough, all we get is a detailed description of what’s not enough.)
Meh, just grasping at straws. And I mentioned before what would be make it false IMHO, to my previous points I have to add that also the oceans have to go to the levels seen just 20 years ago in less than 10 years. Speaking of wiggle room, can you tell us if you agree with one of the few remaining skeptical scientists in the field, Pat Michaels?:
You’re still missing the point. The last twelve years of temperature data don’t show a cooling trend. So your oft-reiterated query about “how much would be enough” to conclude the existence of a cooling trend is irrelevant.
What you are trying to portray as “cooling” since the one-year temperature spike of 1998 was simply the one-year drop coming off the spike in 1999. Since that year, the overall average warming trend has been continuing: e.g., the average annual atmospheric temperature in 2001 was higher than that in 1999, and the temperature in 2005 higher than in 2001, and in 2010 higher than in 2005.
Again, your problem here seems to be that you’re not really grasping the difference between a spike and a reversal in a trend. Look at my earlier example again:
Both these data sets are identical up to the sudden drop-off just after the sharp spike at 20. But after that, the “spike” set continues on average to climb back up from the pre-spike level. The “reversal” set, on the other hand, begins an overall decreasing trend at that point.
If we’re trying to understand general trends in the data, the important thing is not whether any of the post-spike values have surpassed the peak value so far, but rather whether the post-spike values are on average climbing or falling.
Your constant harping on “how much of a cooling trend would be enough to falsify the warming trend” is irrelevant, because we aren’t seeing a cooling trend at all.
Yep, irrelevant, and even more so when the ocean temperature is taken into account.
I still remember that even if a number was offered Pepper just kept on playing the obtuse, in the past I even posted this item made by one of the scientists at Realclimate:
I do consider this to be far in the future, nevertheless even when I propose an early date TOWP keeps coming back with creative ways to say I would not commit to check for falsification, it is clear to me that he is incapable of processing the items that can falsify many aspects of the theory of AGW because he assumes beforehand that because AGW is not scientific that therefore no falsification is possible.
Of course, then one wonders how Pat Michales and other scientists beloved (for very ignorant reasons) by the deniers are able to function.
Here are the basic facts that I think are pretty solid when it comes to global warming:
We know what the normal rate of temperature increase should be during this point in the inter-glacial period.
We know that temperature in the last 100 years or so has been increasing faster than the normal rate.
We have very good understanding of the roles the various atmospheric gases play in the greenhouse effect. We understand what CO2 does in the atmosphere, and we have solid mathematical and physical models showing how CO2 traps heat.
We have very good measurements of atmospheric CO2 concentration which show that CO2 levels have increased dramatically in the last 60 years.
Modeling the CO2 increase in the atmosphere using relatively straightforward models seems to show strong correlation between CO2 and temperature, and accounts for the additional heating we’re seeing.
Since we know of no other mechanism other than human industry for the amount of CO2 rise we’ve seen, we have to conclude that it’s anthropogenic in origin.
(Most important to me) - predictions of temperature from models two or three decades old which assumed human-caused CO2 forcing have proven to be pretty accurate. I’m much more impressed by a model that predicts the future than one which merely explains the past.
Conclusion: Human activity is increasing the amount of CO2 in the atmosphere. This CO2 is contributing to additional heating of the planet.
That’s not fact - it’s the best hypothesis. Using Occam’s razor, it is the most reasonable scientific conclusion to draw.
Then there are the things that, in my opinion, are still on weaker/speculative grounds:
The existence of positive feedbacks that will accelerate the warming over a longer scale.
The existence of negative feedbacks that will moderate warming over a longer scale.
The ability of of the planet/mankind to adapt, and the cost of adaptation over a 100 year span.
The amount of CO2 we will continue to produce in the medium and long term.
The net present value of the cost of future warming.
Cost/Benefit analysis of global warming measured against attempts to stop it.
The pricing of the risk due to variance in possible outcomes.
The correct policy prescription for global warming.
Where I part company with many on the AGW side is that I think the acceptance that AGW is happening really just opens the necessary debate over what to do about it, while many AGW proponents seem to think that once you accept it, the debate is closed and we should do whatever they say needs to be done. It’s a long, long way from “Global warming is happening” to “California should pass a cap-and-trade bill.” or “Global warming is happening, so we should subsidize corn ethanol.”
But as for the existence of global warming itself, I have to accept that the best explanation for observed data is man-caused global warming. Of course this could change if new evidence comes to light, but that is true of any scientific theory. Science doesn’t deal in absolute fact - it deals in models and evidence and working theories.
Sometimes a theory can be validated in so many ways that it seems crazy to say it’s anything but cold hard fact, but even then it only means that it’s almost certainly true over the range of evidence we have measured. Newton’s laws were dead-on and corroborated over and over again - until we stepped out and looked at bigger and faster things. Then it turned out to be an approximation and not universally true.
This is the problem with trying to draw conclusions from short-term trends, by the way. You can find trends in anything, including in random walks, if you just pick the right scale and endpoints of your sample. And when a signal is small and variance is large, the real trend can be hard to spot through the variance.
For example, if you’re a blackjack player with a 1% advantage over the house, but with variance 20X as large, then over 95% of the time your bankroll will be below its peak level. The short-term variance overwhelms the signal. It’s possible for a player to have an advantage over the house, play 8 hours a day, and still be a net loser after six months. It’s just not as likely as him being a net winner over the same period, but it can happen.
In the same way, having a current annual temperature below its peak value is not evidence against global warming - it’s an expected result of a temperature curve that has significant variance compared to the warming ‘signal’. Looking at the variance in weather, I don’t think a 10 year trend is particularly meaningful one way or the other, given the relatively small size of the CO2 forcing compared to normal annual variance. You also have to consider the effects of other trends that overlay the CO2 forcing trend - El Nino and La Nina, the solar cycle, ocean currents, etc.
Also, we should maintain a strong sense of humility regarding our current ability to understand climate. AGW is not as solid a theory as Kepler’s laws or The Navier-Stokes equations describing fluid flow. Those theories deal with rather simple systems, and can be easily tested, repeated, and validated. Our knowledge of the planet’s temperature regulation is not nearly as complete, and the atmosphere itself is a complex system. We’re still learning new things about it and about the Earth’s various feedback mechanisms. So while AGW is the best hypothesis, we need to be careful about drawing sweeping conclusions and trying to predict the temperature 100 years from now. There’s still much we don’t understand.
Can’t argue with any of that, Sam. The one caveat I would offer is this:
Although your “weaker/speculative” #4 is technically correct—namely, that we don’t know for sure how much CO2 we will continue to produce in the medium and long term—there appears to be no convincing political or economic reason to think that (barring some global catastrophe on the scale of the Black Plague or thereabouts) our overall emissions levels will decrease or even stop increasing any time in the next fifty years, for any reason other than deliberate response to climate change issues.
In short, we shouldn’t overstate our ignorance about future levels of CO2 emissions. We certainly can’t predict their exact amounts, but we definitely have good evidence about their general trend.
In broad strokes I agree with you, but basically I’m saying, “we know what the likely trend is, but we don’t know the size of the error bars.”
For example, the current economic downturn has caused a fairly dramatic swing away from the curve of increasing CO2 emissions, and has decreased the rate of growth of CO2 by more than any proposed global warming legislation would have. And no one was predicting it even five years ago.
In general, we overestimate our ability to predict the future. We are often wildly wrong about what the future will look like even five years into the future, let alone one hundred years into the future.
How accurate do you think a 1910 prediction of world CO2 output in 2010 would have been? In 1910, no one predicted the rise of Japan and China, two world wars, the information age, nuclear power, or any number of other transformative events that took place. And the rate of change in the world is accelerating. We don’t have a clue what the world will look like even 20 years from now. Will China still be growing? Or will it implode its own gigantic bubble and revert to the kind of economic output it had 20 years ago? Will oil peak? If so, what will that do to the amount of money we invest in alternate technology? What about telecommuting/telepresence? Will we develop virtual reality so strong that we’ll stop traveling to work, eliminating a huge part of our current CO2 emissions? What about nanotechnology? Improvements in battery technology?
How about war? What would even a small-scale nuclear war do to world CO2 output? What are the odds that nuclear weapons will be used somewhere in the next 100 years? Pretty good, I’d think.
But even these questions only involve extrapolations of current trends. The history of the modern world is one of disruptive technologies that come out of nowhere and change the world. We can’t predict what the change will be, but we can predict that there will be massive change.
Now, since we don’t know what it will be, we still have to extrapolate based on what we know, and that’s what the IPCC has done. And that’s a reasonable approach to take (especially if you offer multiple competing models, which they did). But while it’s the most reasonable approach, that still doesn’t mean that it’s accurate, or likely, or even likely to be in the ballpark. So the error bars we assign to those estimates should be very, very large. Especially on the downside - there’s not much to suggest that we’ll use even more fossil fuels than we do, because we’re limited on the upside by how much there is. But there are many potentially disruptive events that could decrease CO2 emissions, perhaps by orders of magnitude.
You’re almost there. You’re explaining with tremendous vigor that what we’re seeing so far isn’t a cooling trend at all, which is good – and then you’re not quite going on to spell out what would be enough to count as a cooling trend. Don’t just give me an example of a reversal side-by-side with a spike-with-fluctuations; that’s nice to illustrate your point, but I’m out to eliminate ambiguity; just tell me how much colder it needs to get, and for how long, to falsify the position in question.
Mind, staking out that position doesn’t end the debate; it opens one. If, say, you tell me you need to see a drop of at least one degree each year for the next twenty years, I’d probably ask why not at least a tenth of a degree each year for the next twenty years? Why that criterion? Or:
But why that criterion? Imagine for a moment that the oceans (a) hold steady at the current level for the next 10 years, and then (b) spend 10 or 20 or 30 years heading back to the levels in question. Why should that count as warming? (Or, at that, imagine it simply and only holds steady at the current level; why should that count as warming?)
Of course I don’t agree; I have no idea whether, “one of these years, that’s going to turn around.” Maybe it will. Maybe it won’t. I’m not interested in flatly declaring that, one of these years, it will turn around – or that it won’t, for that matter.
And my response at the time: “So if next year is no warmer than this one, and ditto for the year after that, and ditto for the year after that, and ditto for the decade after that, and ditto for the decade after that, and then it actually gets a lot colder in the decade after that – are we still supposed to stand around saying, whoa, hey, let’s stick with this ‘global warming’ conclusion until 2050 rolls around and kicks off a relevant timeframe, eh?” And you helpfully replied that, no, “if for the next ten years we get temperatures close to the 70’s or the 80’s that would do.”
You then followed up with a quote that “anyone who tries to establish the trend in global average temperature with much less than fifteen years data is — in my view — either particularly ignorant of the science, or what is more likely, some sort of flim-flam artist”. Which struck me as odd for someone who just staked out a willingness to do exactly that, but, hey, whatever.
Still, if that’s the criterion you want to keep in play, then I’d of course like to ask why that’s your criterion of choice. Imagine for a moment that temperatures don’t get close to where they were in the '70s or '80s – but do stay at, say, the same place they are right now; do we need a decline to disprove warming, or would enough years of a hypothetical leveling-off suffice?
(And, likewise: you say we could falsify it if 2050-2070 winds up being lower than the 1950-1970 level. What if it winds up simply being the same as the 1950-1970 level? Shouldn’t a criterion to falsify “warming” encompass mere steadiness as well as a cooling drop?)
Meh, I predicted how you would still become the other wall of obtuseness regarding the bone of falsifiability thrown at you.
And the Pat Michaels question was also a test:
As you failed to explain why*, you indeed demonstrate that you are unwilling to check the evidence of why he is saying also that you will kill the skeptics by continuing to follow a stupid point.
When you dismiss so easily one of the few remaining scientists that are concentrating on areas that there is indeed more doubt you are indeed becoming a denier and not an skeptic.
*The reason why is that indeed we are currently in a low solar activity phase with a la nina thrown in for good measure, and we **still **got a year(s) that was(were) an statistical tie with the warmest years on record (and the oceans and other items show how dumb it is to insist there was no warming in the last decade), unless you can explain properly how the current decade will be cooler when the natural forcings increase and are added to the GHGs already in the atmosphere, you are indeed just full of hot air as **Sam **told deniers that follow silliness like this one.