Prev  1  2  3  4  5  6  7  8  9  10  11  12  13  14  15  16  17  18  19  Next

Comments 151 to 175 out of 471:

151. muoncounter at 13:38 PM on 22 December, 2010
     #150: "Check out this ... " Why am I not surprised? I asked you if that website was your source 130 comments or so ago. Where is the published science from this 'originator'? Who are the other authors who've gone on to cite the 'originator'? That site (which begins with nonsensically throwing out 'anomaly analysis') seems to be the basic source for everything you've presented here. To the extent that Lindzen and Choi are debunked here and the extent that you've been shown to be incorrect, that site goes down the debunking trail too.
152. archiesteel at 13:41 PM on 22 December, 2010
     @RW1: "I've never seen the information and analysis he presents here refuted anywhere" Has he every published in a peer-reviewed journal? The fact that you hold him in high esteem is quite meaningless; in fact, if he gets the same results as Lindzen and Choi are getting, he's likely just as mistaken as they are. Too bad your skepticism is only directed towards those you disagree with, and not those who reinforce your initial position. Meanwhile, many people here have successfully rebutted your assertions, and you have yet to offer a counter-argument. I guess we'll just have to take that silence as an admission of defeat on your part.
153. archiesteel at 13:44 PM on 22 December, 2010
     @muoncounter: hey, maybe RW1 *is* George White. That would explain a lot, actually... :-)
154. Eric (skeptic) at 13:56 PM on 22 December, 2010
     RW1, the (lack of) perihelion increase is just another example of nonlinearity in the effects of forcing. The increased solar power hitting the SH is absorbed in the oceans which smooths the extra forcing much more evenly than the NH can. One bit of interesting evidence is that part of the Milankovitch theory is that seasonal extremes melt the ice and release us from an ice age. This occurred 11k years ago when the perihelion was in July and the summer extremes melted the NH ice.
155. Eric (skeptic) at 14:03 PM on 22 December, 2010
     RW1, it looks like the consensus is that site will provide some good practice in spotting incorrect assumptions, logic or math. I can't guarantee anything, but I'll give it a try tomorrow.
156. RW1 at 14:19 PM on 22 December, 2010
     Eric (RE: Post 154), "RW1, the (lack of) perihelion increase is just another example of nonlinearity in the effects of forcing." How do you figure?
157. RW1 at 14:26 PM on 22 December, 2010
     Eric (RE: Post 148), Eric: "RW1, the sun, measured by TSI changes in the historical measurements and proxies, increased by about 0.5 W/m^2 from the depths of the Little Ice Age to about 1900, see fig. 1 in A-detailed-look-at-the-Little-Ice-Age.html The temperature increase, which also involved other factors, was at least 0.5C, maybe more like 1C. With no other factors considered the "gain" is something like 2.5 to 5W/m^2 divided by 0.5 which is 5 to 10, rather than 1.6 The problem, I believe, is you are calculating gain with full solar input (zero to current day) which will yield a much smaller result than a delta of solar input as I demonstrated, albeit crudely, using the LIA." You're assuming the temperature increase was caused entirely by the 0.5 W/m^2 increase in solar power. The overwhelming majority of it could have been caused by a countless number of other things or combination of things - most of which we still don't know. It's well known that the very small increases in total average solar radiance are not enough to cause the warming we've seen since the LIA.
158. scaddenp at 14:26 PM on 22 December, 2010
     "that site will provide some good practice in spotting incorrect assumptions, logic or math" Indeed. Starting with this one: According to HITRAN based simulations, the atmosphere captures 3.6 W/m² of additional power when the CO2 is increased from 280ppm to 560ppm. Of this, the atmosphere radiates half of this up and half down. One of us doesnt understand what HITRAN outputs mean. It seems the site author is also eccentric in usage of word "power". I had no luck finding publications by George White in physics and climate. Anyone else done better?
159. RW1 at 15:08 PM on 22 December, 2010
     Eric, To show you that the global temperatures being 3 C colder at perihelion still coincides with the average gain factor of about 1.6 for net incident solar power, here are some calculations: At perihelion in January, the albedo is closer to 0.4 or nearly 0.1 higher than it is on average. So if we take the increased solar power at perihelion of 347 W/m^2 and subtract out an albedo of 0.4, we get net incident solar power of about 209 W/m^2 (347 x 0.4 = 138; 347 - 138 = 209 W/m^2). At 3 C colder, the earth's average temperature is about 285K. 285K = 374 W/m^2 from S-B. 374 W/m^2 divided by 208 W/m^2 equals a gain of about 1.8, which is not far off from 1.6. The albedo is actually not quite 0.4 in January on average, so if we used .37 instead, it comes to a gain of about 1.7, which is pretty close to 1.6.
160. muoncounter at 15:24 PM on 22 December, 2010
     #159: "At perihelion in January, the albedo is closer to 0.4" Your website's graph 'global monthly albedo' shows the average at 0.27 and appears to put the NH winter seasonal difference 'limit' at 0.032. Thus, in January, according to your figures, the albedo is closer to 0.3. The bulk of this change (as labeled) is due to 'ice amount'. This is used as some form of input to a 'power' equation. Do you include the fact that NH solar insolation above 60N lat is sharply reduced during winter months? So while there is higher albedo due to the greater ice extent, there is very little sunlight falling on that reflective surface. How can there be any material alteration to what you call your 'power' calculation due to these purely seasonal changes? What, then, does this 'gain' actually mean? Please note these questions are not an invitation to merely restate what you've already said here numerous times.
161. RW1 at 16:12 PM on 22 December, 2010
     Eric, I'm sorry again. The increase in average solar power at perihelion is actually 350 W/m^2 - not 347 W/m^2. When this is corrected for, the gain calculation for a 0.4 albedo is about 1.78 and for a 0.37 albedo is 1.7 - pretty close to 1.6. Also, the original gain calculated from 288K is actually 1.64 (390/238 = 1.64). So again, it's very close and certainly same ball park. Most importantly, it's no where near 8 or significantly less than 1.6.
162. RW1 at 16:47 PM on 22 December, 2010
     muoncounter (RE: Post 160), I wasn't getting my albedo numbers from that sight, but I don't think you are interpreting the graph there correctly. The referenced limit is the amount from the dashed line to dotted line, and the peak albedo is actually above the dotted line - making it greater than 0.304. So what numbers do you want to use for average yearly albedo vs. average albedo in January? I've been using a round 0.3 yearly average. How about we use 0.34 then for January? That yields a gain of 1.63.
163. RW1 at 17:00 PM on 22 December, 2010
     muoncounter (RE: Post 160), "The bulk of this change (as labeled) is due to 'ice amount'. This is used as some form of input to a 'power' equation. Do you include the fact that NH solar insolation above 60N lat is sharply reduced during winter months? So while there is higher albedo due to the greater ice extent, there is very little sunlight falling on that reflective surface. How can there be any material alteration to what you call your 'power' calculation due to these purely seasonal changes? What, then, does this 'gain' actually mean?" I don't get the question. The numbers used and inputed for each variable are global averages, so all of what you mention is automatically accounted for.
164. archiesteel at 17:14 PM on 22 December, 2010
     I'm pretty sure discussing perihelion insolation and albedo is quite off-topic. Please stop bloating the thread with such confused, irrelevant and repetitive arguments. Thanks.
165. VeryTallGuy at 18:47 PM on 22 December, 2010
     RW1, you're simply not listening, I'm done. Riccardo @141 do you have a reference or link for how the calculation for surface heat flux change and therefore temperature change is done from the TOA 3.7W/m2 ? As I said in the post, conceptually I'd expect the surface change to be larger, but I'm interested if a rough methodology is available to work through.
166. Riccardo at 22:29 PM on 22 December, 2010
     VeryTallGuy I haven't seen any rough calculations and I don't think it is possible. The problem is that you need to consider the wavelength dependence of both emission by the earth surface and absorption by the atmosphere; also, other forms of energy other than radiative need to be taken into account. In other words, you're asking for the climate sensitivity which proved to be hard to calculate.
167. VeryTallGuy at 23:03 PM on 22 December, 2010
     Riccardo, I found this excellent exposition of the concepts by Chris Colose It turns out that the definition of the no-feedback temperature increase for a forcing is based on the effective emission temperature rather than the actual surface temperature. Using 255K as the effective temperature (that of a notional blackbody with overall emission equal to total net insolation TOA) that gives 1K for 3.7W/m2. I guess that the often quoted 1.2K comes from working through the calculation to give the surface budget accurately for real temperature, without feedbacks, but applying it directly to the effective temperature gets approximately the same answer much more simply. RW1 - if you want to understand this better, Chris's post includes how to calculate for solar forcings, albedo etc.
168. Ned at 00:04 AM on 23 December, 2010
     In the past, I've pointed out that most of our regular "skeptic" commenters appear to follow an unwritten rule never to say anything critical of another's "skeptic" arguments, no matter how far-fetched. So I have to note here how much I appreciate the tone set by Eric (skeptic), who has been very calmly and even-handedly responding to comments from both the pro-consensus and anti-consensus "side" in this thread. This is a real breath of fresh air ... and it's very reassuring to those of us who have been starting to wonder whether there's anyone on the "skeptic" side whose comments here are worth taking seriously. We need more of this. John has created a really great site here, but it's constantly in danger of succumbing to the typical pattern of two noisy "sides" yelling at each other. Anything that tends to break down the homogeneity of these two "sides" is a good thing, IMHO.
169. Eric (skeptic) at 02:37 AM on 23 December, 2010
     Thanks for the praise, Ned. I read all the threads here (or at least the head post) and choose carefully where I can understand and respond to science issues. As I said on another thread, I was brought here after I spewed some "talking point" without doing proper research over on a weather forum that has occasional climate opinion pieces. I have two goals here, to hopefully never make claim that I haven't researched, and second to get critiques of my own, sometimes outlandish-sounding theories. In order to do the second, I have to explain what I mean very carefully which is great practice for the long run. If I can make one useful contribution to the site it would be if someone takes one of my explanations above and cleans it up and turns it into a post, e.g. why lack of warming in the perihion does not disprove sensitivity or something like that.
170. scaddenp at 07:05 AM on 23 December, 2010
     I would have to second Ned's comment. Eric, if you are not actually a scientist, then you are thinking like one. You would be welcome in our tea room anytime.
171. RW1 at 09:48 AM on 23 December, 2010
     VeryTallGuy (RE: Post 165), The questions I asked were perfectly reasonable.
172. RW1 at 10:03 AM on 23 December, 2010
     No one here has adequately debunked anything I've said. No one has yet to explain what is so special about each 1 W/m^2 of additional forcing from CO2 that the system is going to treat it as being 5 (or at least 2.5 times) as powerful as each 1 W/m^2 from the Sun. No one has yet to explain why the oceans will obey radically different physics globally than they do hemispherically to increases in radiative forcing. A few people have acknowledged that of the additional absorbed power from CO2, only half of it can affect the surface because the other half is radiate upward out to space. When asked for a source or some kind of documentation that for the total net forcing to be 3.7 W/m^2, the total absorbed actually need to be 7.4 W/m^2, no one has provided it. Now, I know must have missed answering some questions directed to me here, so please remind me of anything I failed to address to anyone's satisfaction.
     Response: [Daniel Bailey] You have been repeatedly corrected, most recently by KR at 174 below. Please read his comment carefully and review the previous comments others have made. Thank you.
173. RW1 at 12:02 PM on 23 December, 2010
     Eric (RE: Post 169), What numbers would you like to use for the yearly average albedo vs. the average albedo in January? I now realize 0.4 is too high, and it appears like it's more around 0.33-0.35. Do you see that the 3 C colder temperature at perihelion doesn't conflict with the increased solar power and the roughly 1.6 gain factor, and is actually in line with it?
174. KR at 13:33 PM on 23 December, 2010
     RW1 - Quite frankly, it's difficult to know where to start. - The 3.7 W/m^2 forcing for a doubling of CO2 leads to a 1.2°C warming without considering feedbacks. That means 3.7 W/m^2 less IR radiation leaves the atmosphere. That number is the result of a considerable amount of computation, more than I can fit on the back of an envelope, working from basic physics to find how much energy is retained by GHG's. That's equivalent to a 3.7 W/m^2 forcing from solar changes (1.2°C for each 3.7 W/m^2 change), a 3.7 W/m^2 change in volcanic aerosols (1.2°C for each 3.7 W/m^2 change), etc. - Your 'halving' of the 3.7 radiative forcing is nonsense. You've been told that repeatedly, and have not responded. CO2 absorbs all the IR within it's emissivity/absorptivity bands within a matter of meters at ground level pressures. And emits based on it's temperature, somewhere near dynamic equilibrium. It's not just a single-layer atmosphere (where 7.4 W/m^2 absorption of surface IR would account for that); you would have to look at the integrated spectra of surface level IR absorption, the numeric calculations of each layer of atmosphere, etc. But it's 3.7 W/m^2 not making it out of the atmosphere for each CO2 doubling. - Your 1.6 gain makes absolutely no sense to me, nor to any number of other posters. You appear to be dividing apples by oranges. - Your peak-to-peak insolation numbers are meaningless without averaging them over the season; they should be ~50-60% of the peak-peak values (off the top of my head) for seasonal averages. - Climate sensitivity amplifies (to some extent) that change, with the current estimates being ~3°C for a doubling of CO2. - Your raw number calculations for insolation do not include sun angle; that will change those raw numbers considerably. - Seasonal changes are cyclic, which means they average out to a trend of zero (0°C) over time. Seasonal variability is quite large - but the trend over time (30 years for statistical significance) is non-zero, indicating global warming. - The difference between seasonal heating/cooling and long term trends is, quite simply, the trend. Seasonal effects cancel out, trends on baselines do not. - Evaporation and convection in the Trenberth numbers count; very much so. The Trenberth 2009 energy budget is essentially a 3-layer layout: 3-way exchanges between outer space, the surface of the Earth (water and soil), and the atmosphere. All numbers are important. You've indicated that you feel Trenberth was just presenting ad hoc numbers, as I indicated in this post, you're going to have to demonstrate your objections to specific numbers in those budgets to be taken seriously. Given the large number of incorrect or unsourced assertions in your postings, I would find it very difficult to discuss anything with you. You really appear to be focusing on details (bean-counting) without a good view of what's happening on a larger scale, and are getting tied up in the (incorrectly summed) numbers.
175. Eric (skeptic) at 13:38 PM on 23 December, 2010
     Hi RW1, sorry I haven't answered your 172 post yet. I am looking at the paper you linked that said "According to HITRAN based simulations, the atmosphere captures 3.6 W/m² of additional power when the CO2 is increased from 280ppm to 560ppm. Of this, the atmosphere radiates half of this up and half down." and looking at the Collins paper http://www.cgd.ucar.edu/cms/wcollins/papers/rtmip.pdf and others linked from Judith Curry's site http://judithcurry.com/2010/12/05/confidence-in-radiative-transfer-models/ So far I have not found a complete derivation of such a quantity as "captured additional power" for the atmosphere but a changes in LW forcing at various levels in the atmosphere. Hopefully I can reconcile those and determine whether the "divide by 2" idea is valid or not.

Prev  1  2  3  4  5  6  7  8  9  10  11  12  13  14  15  16  17  18  19  Next

Post a Comment

Political, off-topic or ad hominem comments will be deleted. Comments Policy...

You need to be logged in to post a comment. Login via the left margin or if you're new, register here.