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GG, I'm not a climate scientist, so if you want to challenge them you have my blessings. ;-) But I try to get people to prepare their arguments better according to the best practice of physics. That's why I try to pin down time periods that people are talking about, for example, and actual magnitudes of phenomena. As I understand it, low pressure systems/storms have made incursions into the Arctic historically-- in the "traditional model" as you would have it. So, with the increased energy in the global system (global warming), it would be reasonable to think that these incursions might occur more often, or be stronger, or persist longer. All of the above or some, obviously, depending on physics. That's why I used the term "enhanced" natural variations. Now, I have suggested in the past that the actual climate scientists should be more assertive about attributing extreme events to global warming, and that is beginning to happen. But you appear to be suggesting that there is some kind of state change, based on a couple of years of anomalous weather. You seem to have an idea of how the transition to a new equilibrium would happen in a complex system, but you are compressing the time element at least, and overstating the change in physical parameters, at least as I understand the magnitudes.
Toggle Commented Mar 15, 2017 on PIOMAS March 2017 at Arctic Sea Ice
Golocyte Golo, From following the topic, I get the sense that climate scientists are focused more on characterizing shorter term changes. As I mentioned, there is an active debate about the role of the Arctic in the global model. So, some would argue that whatever you are observing now falls into the category of enhanced natural variations, rather than an intermediate non-state. And this would be dominated by tropical inputs. But if we were in that intermediate condition (far out to sea relative to the islands of the attractors), wouldn't the answer to your suggestion of hints be "no"? I think it is more fruitful to try to pin down the shorter term phenomena that we can be definitive about, particularly in the context of the ongoing political conflicts on the subject.
Toggle Commented Mar 14, 2017 on PIOMAS March 2017 at Arctic Sea Ice
Golocyte Golo, I know this is not a popular question, but when you used the term "ice free arctic" previously, were you talking about "ice free" for 12 days, 12 weeks, or 12 months? The same question arises with what you are asking now: What do you mean by "alternate" circulation pattern? Do you mean an actual "climatological" change, that lasts 30 years? Obviously, any pattern that we actually observe is possible, by definition. Perhaps if you were more specific it would be easier to clear things up. The issue of the jet stream and modulation of the Coriolis effect is the subject of an actual scientific debate, so there is information available.
Toggle Commented Mar 13, 2017 on PIOMAS March 2017 at Arctic Sea Ice
Sam, It's interesting that you say that. Everyone I've ever worked with/for has told me that my value was particularly in what you call gestalt thinking: Seeing the path to an elusive solution. But the first time someone (kindly) said that it was a mathematical physicist that I asked for help because... I didn't know how to "do the (particular) math". In other words, seeing the path, even when others don't, doesn't matter, if you can't walk. A very valuable lesson; I've learned it at every level of development, from people with more experience than I had. You can't wing it, and you can't make stuff up, however clever you are (or think you are). So, what we are talking about here has nothing to do with complex systems. It has to do errors from Physics 101. I try, from time to time, to pay the lesson forward.
Toggle Commented Mar 5, 2017 on PIOMAS February 2017 at Arctic Sea Ice
OK guys. I have admired this blog for its ability to convey lots of excellent observational science. I have learned about the complexity of the Arctic geography and physical systems-- ice transport, melt ponds, leads and compaction, all the "seas" and how each has its own characteristic interactions, and so on. That richness of information is great, but in the final analysis, as I said earlier in a response to ER, the "other side" gives no quarter in this conflict. To my mind, right or wrong, the reality/science-based community has to be really committed to a high standard. The actual climate scientists, who are subject to all kinds of abuse and time wasted refuting spurious arguments, would probably appreciate some support on this front. If it's OK for people "on our side" to make speculative arguments with no physical basis, and dismiss the "rules" that got us to where we are in science and technology, then it becomes impossible to criticize the Denialists. But, if that's the approach that makes you comfortable, "be happy in your work."
Toggle Commented Mar 4, 2017 on PIOMAS February 2017 at Arctic Sea Ice
Frank said: "the information gained by considering the influence of several factors simultaneously." Frank, generations of scientists have spent their lives trying to eliminate "the influence of several simultaneous factors". A "gold standard" experiment is one in which we gain information about how a single variable influences another single variable. All of our knowledge of the physical world is built up this way. Step by forward step. Which is why my method is correct and Rob's is incorrect. This is very basic "scientific method" and "philosophy of science" and "best practice" and so on. This is why we have Ockham's Razor. This is why we have formal statements of experimental hypotheses. So, unless you can tell me why any serious investigator would refrain from taking the simple step of testing for a correlation as I described, you are not engaging in a serious debate.
Toggle Commented Mar 3, 2017 on PIOMAS February 2017 at Arctic Sea Ice
Frank, What ever happened to being calm and polite? I was snarky (which I have said I will avoid) about Rob (not Bill, with whom I didn't interact) because I thought he was being defensive and not forthcoming with his process. Now you are taking a similar oppositional attitude when all I did was explain my own reasoning, as requested. Anyway, I'm not following what you are saying about "a continuous function". It's data points, some are daily and some are monthly averages. When we fit a straight line, which in science we always try first if the eyeball reads it that way, then we are establishing a continuous function. But what I am most not getting is what you are saying about "first to fifth guesses". I haven't read every single post and every single comment, but I thought this idea of Land Snow Cover influencing the melt rate was exactly the new idea that Rob came up with. In fact, what I said when I was "asking nicely" for more information was that I thought it was an interesting hypothesis well worth exploring. The question at hand, from my perspective, is the correct methodology, which is what we are disagreeing about. What would be the value of me testing for the correlation?
Toggle Commented Mar 3, 2017 on PIOMAS February 2017 at Arctic Sea Ice
Frank, That sounds like what I thought Rob was doing. But I don't see the physical justification for such an approach. First, you asked me why I would do a best fit on the (yearly) data instead of subtracting the last data point from the first. Well, why would we ever do a best fit? The answer is, because we are trying to distinguish the underlying signal, which is the result of a physical process, from the noise, which may be the result of other physical processes. The single most important thing I've learned lurking here myself is that there is an enormous level of variability. So, the first step I would take to avoid error is to determine just how correct my assumption of linearity would be, and also to get a slope that has not been influenced by some storm, on August20, for example. Now, having decided that the melt rate is constant, I would try to imagine what physical factors determine that melt rate. If the first guess is that Land Snow Pack on June1 has an effect on the melt rate, why would you call it "convoluted" to simply test for a correlation? It is, to me, the obvious next step.
Toggle Commented Mar 3, 2017 on PIOMAS February 2017 at Arctic Sea Ice
Neven, I think I did show my work, which I stand by, and which I'm happy to discuss with Frank. This is difficult to do if we can't agree about what we are disagreeing about. If that's OK, I will continue if Frank indicates that he is interested. I will try to avoid snark, and if I find myself getting too frustrated I will simply move on, which I was ready to do before he commented.
Toggle Commented Mar 3, 2017 on PIOMAS February 2017 at Arctic Sea Ice
Frank Pennycook, I understand what you are saying. I appreciate that someone who has a grasp of the math and can communicate his position wants to help clarify things. For starters, could you just explain, as a mathematician, "the work that Rob did"? I don't care about using spreadsheets-- I just assume that's what people use because they are available-- but I still haven't seen from him any description of a process that I could replicate. I can imagine some approaches that I might use, for a multi-variate analysis, but I certainly would not use them before I established a correlation that is consistent with physics. In any event-- go ahead and describe Rob's actual method from what he has written, and we can deal with the physics later.
Toggle Commented Mar 3, 2017 on PIOMAS February 2017 at Arctic Sea Ice
Rob Dekker said: Something like : "Rob, you did nice work correlating three different variables (land snow cover, water-close-to-ice, and plain old ice 'area'). But you didn't do "nice work". What you did may even qualify for that famous quote: Not Even Wrong. It's hard to tell if there's anything "right" in your "analysis", but in an effort to be positive, I provided you the correct methodology-- not because I want you to do it for me, but because it would be a way for you to gain some understanding. If that's too painful, OK. I also provided it so that lurkers could see the difference. It might discourage some, but if people do want to be "citizen scientists" they should be willing to put in the effort to read and understand, and learn the terminology and methods, so that you can communicate your work in a clear and complete form. You can't just wing it and make stuff up.
Toggle Commented Mar 3, 2017 on PIOMAS February 2017 at Arctic Sea Ice
Rob Dekker, Now you are being silly. Here's a quote from your original post: When I use this formula as the 'predictor' I get improved correlation numbers (especially for the shorter terms if you use only 'Area' or 'Extent' as a predictor), which suggests we are on the right track! But what I was really interested in, is if by tweaking these weight factors (which after all were just educated guesses), if we can improve the correlation numbers even more. If it turns out that the 'optimum' correlation is way off from the weight factors I suggested above, then we know that the physical effects of 'albedo' amplification are simply not significantly visible in the later ice cover numbers. So I used the 1995-2012 series (long enough for statistical quantity and short enough to not be affected by completely different melting regions) and tweaked the numbers until I found optimal correlation. Either you used some software to get your "correlation number" (and your "regressions") or you were just pretending-- what we would call "citizen scientific fraud". So, to get the correlation, click on the same icon, or type in the same command, or whatever the mechanics are in your software. It really sounds like you just don't want to find out if what you thought-- that there would be a correlation-- is wrong. That's not uncommon; that's why we have the term "confirmation bias".
Toggle Commented Mar 2, 2017 on PIOMAS February 2017 at Arctic Sea Ice
Rob, I've given you the entire procedure. The remainder is up to you. Use the data you've downloaded and follow the steps. If you get a correlation, then you can "publish". I will be very interested in seeing the results. (And please, read the steps over a few times, carefully, and note what is emphasized in bold type. I read your explanations multiple times to be sure I understood them.)
Toggle Commented Mar 1, 2017 on PIOMAS February 2017 at Arctic Sea Ice
ER and RobertS, If you check back you will see that I have been arguing against predictions but for projections. You are ignoring the difference. RobertS, yes, the FF are really flying around here, and people are using terms that they don't understand and aren't even interested in reaching an internal consensus on what the words mean. But, and I don't know why you would object, there are many topics where people can become better at scientific/quantitative reasoning and reach valid conclusions. We can figure out, for example, whether or not the Land Snow Cover has an effect on the rate of ice melting between June 1 and September 1. So, why do you object, and what's your plan?
Toggle Commented Feb 28, 2017 on PIOMAS February 2017 at Arctic Sea Ice
Elisee Reclus, Yes and no. There's a difference between what is speculative and what is wrong. That's what I am working on establishing, which I tried to convey in our previous conversation. Here you are citing "summer minima" as having some significance, when that number means as much as "the millenium" or some other numerologically striking value. Do you really want to engage in that kind of propaganda exchange with the masters of BS we are up against? You will surely lose; shouting is what they do best. As difficult as it may be, we are in the position of Caesar's Wife. If someone is going to debate a Denialist, he or she better not be making mistakes from seventh-grade algebra. And there are things we can explore here as a way of training our thinking, like my suggestion to Rob on looking for factors that might influence the melt rate. What's the harm, as long as it is done correctly.
Toggle Commented Feb 28, 2017 on PIOMAS February 2017 at Arctic Sea Ice
Elisee Reclus, If that is addressed to the discussion I am trying to have with Rob-- it may well be true. But as I have been saying all along to no effect, apparently, you have to be specific. Are we talking about the winter maximum and summer minimum, or June 1 and September 1? Rob could supply some answers if he wanted to, or anyone willing to download and organize some data.
Toggle Commented Feb 28, 2017 on PIOMAS February 2017 at Arctic Sea Ice
Rob, If you want to be a "citizen scientist", then you have to be willing to undergo "peer review", and you should be willing to "defend your thesis". It sounds like you are indeed very confused about the math and physics, and unwilling to take the opportunity to get a better understanding. I gave you the correct way to do this. If you have all the data set up in your spreadsheet, why don't you give it a try-- it will take a couple of minutes at most. There is a lot of information that could be developed if you put aside your ego.
Toggle Commented Feb 28, 2017 on PIOMAS February 2017 at Arctic Sea Ice
Rob Said: @zebra, I understand. Let's see if this helps. Using this formula : delta (ice) = alpha - beta*(MF) Calculate "MF" for each June between 1992 and 2015. Then calculate 'delta (ice' for each June between 1992 and 2015 as well. That results in what we call a "scatter plot", with "MF" at the x-axis and 'delta (ice)' at the y-axis. Something like this (from the Wiki page on regression analysis) : https://upload.wikimedia.org/wikipedia/commons/3/3a/Linear_regression.svg On that scatter plot we then run simple regression analysis which results in an offset (alpha) and a slope (beta). Does that make sense ? Rob, I think I could rewrite what you are saying here to make it clearer, but it is clear to me already that you have a very confused understanding of the math and the physics. In case this is not obvious to others, I'm going to go through what I would consider the correct way to approach the question. 1. The question is: Does an initial condition in June (Land Snow Cover) have an effect on the sea ice minimum (in September)? 2. Let's look at the Charctic interactive graph for extent. We zoom in on June first to October first. We observe that June 1 through Sept 1 looks like it might be a straight line with some wiggles or "noise". (This is ice extent on the y axis and days on the x axis.) 3. We use the regression function to find the straight line that best fits the data for each year, June1 to Sept1. This gives us the slope of the line, which is the rate at which the ice melts, for each year. 4. If June1 Land Snow Cover has an effect, that rate is what would be affected. 5. Now, we have a list of rates for each year. 5a. We can look for a trend by doing a regression again, with rate on the y axis and years on the x axis. Is the rate increasing? 5b. We can list the the rate for each year next to the June LSC for each year, and look for a correlation. Does the rate go up/down when the LSC goes down/up? You have that function on your spreadsheet as well. So, to continue the theme that this all started on for me: Yes, it's great for people to look for quantitative information (first approximations) as part of understanding what's going on and countering the Denialists. However, we have to have the fundamental principles right and be disciplined in how we reason and how we communicate it.
Toggle Commented Feb 27, 2017 on PIOMAS February 2017 at Arctic Sea Ice
Rob, Of course I didn't understand what you were doing-- why would I keep asking these silly questions otherwise? :-) I think the cause of my confusion all along may be that you are calling delta (ice) = alpha - beta*(MF) a "regression formula", and referring to "many regressions". Again, could you just describe what you are actually doing there, with what data, without using the term regression? (Except maybe to say : "then I click on 'regress' in my spreadsheet.")
Toggle Commented Feb 26, 2017 on PIOMAS February 2017 at Arctic Sea Ice
Rob, I just skimmed your paper before commenting and I wasn't clear what you were trying to do. I now see that you are trying to improve the correlation beyond what we would expect just looking at the initial value as I do with the WFT graph. OK, so let's try to get the communications clear. First, we seem to agree that "albedo amplification" and "albedo feedback" can be confusing, but let's put that particular terminology aside for the moment. Second, I think your hypothesis about land snow cover is a nice bit of reasoning, and I would like to see it developed further. However, I've now read your paper over carefully, (as well as the post Bill referenced), and the particular terminology there has me puzzled. What you are calling a "melt formula" seems to be what I would call a "melt factor", and I am assuming that what I would call the "melt formula" is the form (amount of melt) = alpha+beta*(melt factor). Could you just demonstrate step-by-step how you calculated your prediction for the amount of melt for 2016, instead of describing it in words?
Toggle Commented Feb 25, 2017 on PIOMAS February 2017 at Arctic Sea Ice
Hans G, You hit on one of my pet peeve topics there. We on the East Coast have plenty of our own wind offshore, and we just got the first US offshore project up and running. We would have expected HRC to recognize our natural desire to put our under-utilized ports and boatmen to work rather than buying energy from the bigots who voted against her. More investment on the turbines, but perhaps less trouble and expense than routing HVDC lines over land. What a difference a vote makes...sigh
Toggle Commented Feb 24, 2017 on PIOMAS February 2017 at Arctic Sea Ice
Rob Dekker, I hope you take this in the spirit of constructive criticism; I don't want yet another person mad at me. It seems to me that if you start with less(more) ice in June, you will inevitably end up with less(more) ice in September. http://woodfortrees.org/plot/nsidc-seaice-n/from:1980.42/every:12/normalise/plot/nsidc-seaice-n/from:1980.67/every:12/normalise I don't know how you would attribute this to albedo at all, except insofar as the January extent might be influenced by retained energy in the system. But that's a stretch.
Toggle Commented Feb 24, 2017 on PIOMAS February 2017 at Arctic Sea Ice
Robert S, I don't know how far back you followed the discussion. Some contributors were calculating heats of fusion and energy absorption and so on over the Arctic area. I started out defending them and the idea that you don't need to have super-computer level models to draw valid (approximate) quantitative conclusions. When scientists and engineers start to solve problems-- I mean real problems, not plug-in school problems-- that's how we begin. But, just because you are looking for numbers like orders of magnitude, or "is it going up or down", or relative rates of change, and so on, you don't get to ignore the rules. That means clearly stating the boundaries of what you are trying to demonstrate, and justifying your quantities and conclusions. The question at hand had to do with insolation, albedo, phase transitions, and the "ice-free" condition, and whether that condition represented a "tipping point". So, clathrate bombs, for example, are irrelevant. Also ocean and atmospheric currents bringing energy in. Nor is the historical loss of volume useful. It's a simplified hypothetical case, not the whole shebang. You have this big ocean with a big ice covered island, and part of the ocean has ice and part doesn't, depending on the time of year. Will there be a complete state change if the entire ocean is ice free for three days? Three weeks? Three months? Will the island ice melt? Will the rate of change of planetary energy balance double? Will we all be doooomed? Quickly playing with the numbers, I would say no, but I am willing to be corrected by a rigorous argument.
Toggle Commented Feb 23, 2017 on PIOMAS February 2017 at Arctic Sea Ice
Glenn, Robert S, This kind of physics involves being able to characterize temporal and spatial relationships, propose a causal narrative based on fundamental principles, and establish (simple) quantitative models therefrom. I've tried to give some guidance on how you might constructively "do the math", but if you aren't interested in that elementary level of rigor, I can't force you to try.
Toggle Commented Feb 22, 2017 on PIOMAS February 2017 at Arctic Sea Ice
Glenn, I appreciate your reply to John Bilsky. No need to apologize; this is not my first internet "debate" rodeo. First, I think others had previously made the point I was trying to make, which is that momentarily crossing the "no ice" threshold does not in itself represent some kind of "tipping point". There is already lots of "blue ocean" when we hit the minimum last year. Something like 11 million square kilometers, if we just subtract about 4 from about 15, using the extent graph. 1) I suggest you calculate the net energy absorption for 24 hours as that number increases by say 1 million at a time, until you get to 15, and plot your results. 2) It would also make sense for you to think about the fact that all that blue ocean does re-freeze. Maybe a little less each year, but there is no catastrophic cascade going on at this point. So, where is the great accumulation of all the stored energy you are talking about?
Toggle Commented Feb 22, 2017 on PIOMAS February 2017 at Arctic Sea Ice