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muoncounter at 15:24 PM on 22 December 2010Lindzen and Choi find low climate sensitivity
#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. -
RW1 at 15:08 PM on 22 December 2010Lindzen and Choi find low climate sensitivity
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. -
Renewable Baseload Energy
Interesting article here from Scientific American on wind farms and fish schools. Gist of the article (at least the part interesting to me) is that by studying fish schooling (optimized for minimum energy in moving from place to place) and taking that analysis to wind farms (vertical turbines, closer spacing, aiming to provide maximum energy extraction) can result in a 10x higher energy density for wind farms. That's 1/10 the land use for the same energy provided. -
scaddenp at 14:26 PM on 22 December 2010Lindzen and Choi find low climate sensitivity
"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? -
RW1 at 14:26 PM on 22 December 2010Lindzen and Choi find low climate sensitivity
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. -
RW1 at 14:19 PM on 22 December 2010Lindzen and Choi find low climate sensitivity
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? -
Eric (skeptic) at 14:03 PM on 22 December 2010Lindzen and Choi find low climate sensitivity
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. -
Eric (skeptic) at 13:56 PM on 22 December 2010Lindzen and Choi find low climate sensitivity
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. -
archiesteel at 13:44 PM on 22 December 2010Lindzen and Choi find low climate sensitivity
@muoncounter: hey, maybe RW1 *is* George White. That would explain a lot, actually... :-) -
archiesteel at 13:41 PM on 22 December 2010Lindzen and Choi find low climate sensitivity
@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. -
muoncounter at 13:38 PM on 22 December 2010Lindzen and Choi find low climate sensitivity
#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. -
RW1 at 13:21 PM on 22 December 2010Lindzen and Choi find low climate sensitivity
Eric, Check out this more detailed explanation and satellite analysis of these things by physicist/climatologist and originator George White: http://www.palisad.com/co2/eb/eb.html I've never seen the information and analysis he presents here refuted anywhere, and I've seen many try and fail totally. It's the single most damning piece of evidence against AGW that I've ever seen. I also don't think it's a coincidence that G. White's sensitivity estimate is about the same as what Lindzen and Choi are getting - albeit via somewhat different methodology. -
RW1 at 13:03 PM on 22 December 2010Lindzen and Choi find low climate sensitivity
Eric, Getting back to the perihelion point, here it is from a different angle: Let's say the total average incident solar power increases from 340 W/m^2 to 343 W/m^2 as a result of the earth's orbit moving closer to perihelion. This results in a new, higher net incident solar energy of 240 W/m^2 (343 x 0.3 albedo = 103, 343 -103 = 240), which is an increase in radiative forcing of 2 W/m^2 (240 W/m^2 - 238 W/m^2 = 2 W/m^2) - the same as from a doubling of CO2. If according to the AGW theory, the system's response will be to greatly amplify the additional 2 W/m^2 from CO2 to about 16 W/m^2 via large positive feedbacks, why doesn't the system do it with the same 2 W/m^2 increase in radiative forcing from from the Sun? The observed temperature changes are nothing anywhere near 3 degrees C for this additional 2 W/m^2 of solar power. Even better, let's take the last 3 W/m^2 increase that occurs at peak perihelion (347 W/m^2 to 350 W/m^2 for a net of 2 W/m^2 albedo adjusted). The system doesn't respond by amplifying that last 2 W/m^2 8 fold, but somehow it's all of the sudden going amplify the next 2 W/m^2 from C02 8 fold? Again, does it make physical and/or logical sense that the system is somehow all the sudden going to treat such a small increase radically differently than it does both the last 0.5 percent and the original 99+ percent? -
muoncounter at 12:54 PM on 22 December 2010A detailed look at climate sensitivity
#62: "So if the ocean has quickly absorbed the heat, it will also quickly absorb the CO2 as soon as we stop producing it." The oceans do nothing quickly; see the graphs here. Oceans are absorbing CO2 now, as they are acidifying. You can't just declare oceans 'quickly absorb the CO2 as soon as we stop', as the oceans might might just give it right back to us (if we stop; that's a good one). See the ocean acidification page; you will find some parts of the ocean are sourcing CO2, while others are sinking it. "the paleo record shows a distinct nonlinearity in the region we are in that indicates the opposite of "tipping points" but rather a stabilization in temperature." In this and in #60, you've made a lot of grand generalizations. In order for general statements like as oceans warm over hundreds or thousands of years, CO2 is released in a more or less linear fashion and longer term sensitivity only applies to glacial to interglacial transitions to be accepted into the debate, you must provide some evidence. -
Eric (skeptic) at 12:43 PM on 22 December 2010Lindzen and Choi find low climate sensitivity
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. -
Eric (skeptic) at 12:16 PM on 22 December 2010A detailed look at climate sensitivity
e, thanks for responding. I will obviously have to look at each study. The biggest difference is that short term amplification from water vapor feedback cannot be compared with long term amplification from a CO2-temperature feedback cycle. Even if we argue that the paleo studies were correct (no other unmeasured factor caused the majority of the temperature increase which then caused the CO2 increase by many centuries of ocean warming), that CO2 to T to CO2 amplification factor does not apply to water vapor for many reasons (e.g. it is not seasonal or geographic unlike water vapor which is). Another key factor is that the ice age to interglacial transition used to estimate sensitivity encompassed a nonlinear change in the warming effect of water vapor (in the present climate there is a much larger ratio of cooling effects from water vapor to warming effects than in the ice age climate). The only valid use of paleo sensitivity is the argument that CO2 increases have short-circuited the long slow feedback process and will emerge in 3C warming after ocean inertia. My very simple answer to that dilemma is that CO2 is sequestered with ocean turnover just the way heat is sequestered. So if the ocean has quickly absorbed the heat, it will also quickly absorb the CO2 as soon as we stop producing it. You may see that as a good argument for the many ideas on the solutions threads here and I agree and I agree with those threads. But I also realize that the paleo record shows a distinct nonlinearity in the region we are in that indicates the opposite of "tipping points" but rather a stabilization in temperature. -
RW1 at 12:15 PM on 22 December 2010Lindzen and Choi find low climate sensitivity
Eric, @Eric 144: "You then stated 1) that an increased radiative forcing in the system (atmosphere plus surface) would produce the same ratio of surface radiative increase (i.e. the gain again). And 2) the 3C rise in temperature postulated for the doubling of CO2 would produce a 12 W/m^2 increase in surface radiation by applying S-B to the delta T. And 3) 12 divided by 1.6 is too large for CO2 to produce." No, not quite. I'm saying the 3 C rise requires an increase in surface power of 16 W/m^2 for a gain of 8 (8 x 2 W/m^2 = 16 W/m^2), which is 5 times the 3.2 W/m^2 increase in the surface power from each 2 W/m^2 coming in from the Sun. The AGW theory of a 3 C rise in temperature requires the system to respond to each 1 W/m^2 of power from increased CO2 5 times more powerfully than each 1 W/m^2 of power coming in from the Sun. -
scaddenp at 12:03 PM on 22 December 2010Lindzen and Choi find low climate sensitivity
"3.7 W/m^2 is the total absorbed or captured power for a doubling of CO2, correct?" NO! It is not. 3.7W/m2 is the equivalent radiative forcing you would get from double CO2. eg. Doubling CO2 would give you the same impact say a solar forcing of 3.7W/m2. This confusion and insistence on halving it is getting in the way. All of the absorption, re-emission in all directions, re-absorption etc etc has to be done in the complex RTE codes. (eg you can find a MODTRAN calculator here). Net result is an intensity out which is used to calculate the radiative forcing. "power" is also a slightly confusing term to use - usually used in context of energy conversion. Here we are talking about an energy flux. -
RW1 at 11:48 AM on 22 December 2010Lindzen and Choi find low climate sensitivity
Eric (RE: Post 144), The amount of power from the Sun that hits the surface and is re-radiated as LW infrared is about 238 W/m^2. However, the total power at the surface is 390 W/m^2 - not 238 W/m^2, because GHGs and/or clouds are absorbing and re-radiating some of that 238 W/m^2 back toward the surface, which in effect, is delaying or slowing down the release of the 238 W/m^2, causing the surface to be warmer than it would be; or causing the surface power flux to be 390 W/m^2 instead of 238 W/m^2. The gain represents the increase in surface power or increase in surface temperature as a result of there being GHGs and clouds in the atmosphere. In effect, the gain factor of 1.6 means that due to the greenhouse effect, it takes about 1.6 W/m^2 of power at the surface for each 1 W/m^2 of power to leave the system, offsetting each 1 W/m^2 entering the system from the Sun. -
A detailed look at climate sensitivity
Eric, Paleo studies were not the only source for calculating climate sensitivity discussed in this post. Also discussed were measurements based on recent volcanic eruptions and on the modern warming trend itself. Both of these reflect short term sensitivity (and are obviously applicable to the current climate regime). The results from these studies agree with those from the long term paleo studies. Furthermore, the bottom-up physical simulations agree with the top-down statistical studies. Thus, the evidence does not support the suggestion that modern short term climate sensitivities vary substantially from those derived from paleo studies. -
Eric (skeptic) at 11:02 AM on 22 December 2010Lindzen and Choi find low climate sensitivity
RW1, thanks for the reply. Ignoring evaporational cooling for now, I think what you were trying to say in #61 is that a particular amount of solar energy absorbed in the atmosphere and on the surface (238 W/m^2) turns into 390 W/m^2 of surface radiation or a "gain" of 1.6 You then stated 1) that an increased radiative forcing in the system (atmosphere plus surface) would produce the same ratio of surface radiative increase (i.e. the gain again). And 2) the 3C rise in temperature postulated for the doubling of CO2 would produce a 12 W/m^2 increase in surface radiation by applying S-B to the delta T. And 3) 12 divided by 1.6 is too large for CO2 to produce. Statement (2) seems correct. But (1) means that the gain is always the same whether dealing with the full amount of solar forcing or a delta in solar forcing or a delta in CO2 forcing. I definitely agree that the "gain" should be the same whether for a delta in solar or a comparable delta in CO2. But gain is probably not a constant over the range of solar forcing. The "3C" proponents would have to show that gain is larger at the pre-industrial equilibrium than over the entirety of solar forcing, and I don't think it's hard to argue that gain is nonlinear with warming since water vapor is highly nonlinear. With a larger gain, they can argue that the relationship in (3) holds. In fact your analysis brings to mind a similar problem I have with the paleo sensitivity analysis. There is an assumption that the temperature to CO2 relationship in going from a frozen planet to unfrozen is the same as from unfrozen to slightly warmer unfrozen. Both your analysis and paleo one here detailed-look-at-climate-sensitivity.html seem to use the same basic but faulty assumption that forcing-to-temperature elationships over colder ranges of climate are applicable to warmer ones. -
archiesteel at 10:43 AM on 22 December 2010We're heading into an ice age
@kdfv: November 2010 is the hottest on record.Which is more significant? Summer snow in a La Niña year, or the hottest November in one of the hottest (if not *the* hottest) year?
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RW1 at 10:34 AM on 22 December 2010Lindzen and Choi find low climate sensitivity
VeryTallGuy (RE: Post 137), Let's take this step by step: 3.7 W/m^2 is the total absorbed or captured power for a doubling of CO2, correct? If not correct, then your saying the total absorbed power is 7.4 W/m^2? Some other amount? I've read much of the IPCC reports and I've been studying this issue for quite a while now - nowhere have I seen that the total captured power from a doubling of CO2 is 7.4 W/m^2 for a net 3.7 W/m^2 because only half of the absorbed power goes down. Where and in what way specifically does the IPCC, or any other climate research paper or document, say this? Also, what you are describing above regarding the 4 W/m^2 increase at the TOA is the total amount of increased radiation to space that will occur to achieve equilibrium, assuming there is 4 W/m^2 increase in power at the surface. However, that is only possible if all the absorbed 4 W/m^2 of power is directed toward the surface instead of only half. If it's only half, the "net change in power emitted at the top of the atmosphere" would only be 2 W/m^2. What I'm getting at is the question boils down to what the total absorbed power is. Again, you're saying the total absorbed is about 8 W/m^2 for net of 4 W/m^2 because only half can affect the surface, correct? My orbital forcing reference is from Wikipedia, which I checked against a few other sources. According to them the range is 1,413 – 1,321 W/m^2 perihelion-aphelion. Divide by 4 to get the average, which is a little over 20 W/m^2 (actually 23). Subtract the Earth's albedo of about 0.3 and it's a net increase of 14 W/m^2 at perihelion. Also, I didn't say or imply there was an average increase in radiative forcing from orbital eccentricity. As stated before, I'm well aware that the increase from CO2 is on top of the current average total. -
muoncounter at 10:14 AM on 22 December 2010It's freaking cold!
#60: "attributing global warming solely to CO2" Guess you missed this page. Be sure to look for the key distinction between 'forcing' and 'feedback'. For example, many people seem to think its warming because of water vapor; something has to start the warming before an excess of water can evaporate. So water vapor is a feedback, where CO2 is a forcing. Your second point about temperature measurement uncertainty is also moot; satellite temps and ground temp records are resolved in a number of SkS articles (some by Ned). Keep digging, you'll find nuggets of gold buried around here. -
Mike H at 09:58 AM on 22 December 2010It's freaking cold!
Ned, I agree that I was referring to our local (UK)situation, and I also concede that the shift in the jet stream that has led to these conditions has probably also caused higher than normal temperatures in Iceland. The difficulty I have is in attributing global warming solely to CO2 emissions, and I have now read the posts referred in the response to my original post, which seem to support the view that other factors have a much stronger influence - but governments (apparently guided by climate scientists)seem to focus only on rising CO2 levels. The other area of difficulty lies in the reliance upon satellite data where the measurement uncertainties are of a similar magnitude to the reported temperature rise / decade, and all this in an extremely complex environment with multiple independent variables.Moderator Response: The role of CO2 relative to other factors is discussed here.
The reliability of temperature records is discussed here.
Finally, the ability to make predictions given the complexity of climate is discussed here.
Per this site's comment policy, please post your specific questions or comments in the appropriate thread. This ensures that your posts are viewable by anyone researching a particular question, rather than being randomly strewn about the site. In the future, please consult the List of Skeptic Arguments prior to posting and ensure your comments are made in the appropriate thread. -
RW1 at 09:55 AM on 22 December 2010Lindzen and Choi find low climate sensitivity
Eric (RE: Post 139), Trenberth is just listing evaporation and thermals for reference purposes - neither actually contributes to the radiative budget and/or balance. It's just one more confusing and ambiguous component of that diagram. BTW, if you don't believe me or want to check yourself, run all the numbers he lists - the 80 W/m^2 for evaporation and 17 W/m^2 aren't included in the total radiative flows to achieve power in = power out. -
Alec Cowan at 09:35 AM on 22 December 2010We're heading into an ice age
@kdfv #186 Yes. Summer snow in Australia first ever recorded in: a) 2012 b) 1921 c) 1856 d) 1884 Guess!! (A hint: think about what you need to record summer snow) The Bureau of Meteorology of Australia has information about. For example, a page with recommendation for buildings in the cool temperate region states: "The cool temperate climate has mild to warm summers and cold winters. In the higher parts of the Snowy Mountains, snow can fall at any time of the year. In Tasmania, summer snow has been reported at elevations as low as 300 m." @archiesteel #185 The blunder in Tom Löber's link is announcing that in the middle of December. The same way I'll soon be able to report that last two weeks of December were hot record here in Buenos Aires, possibly some 3 or 4°C above the previous hot record for December. The link in 184 only claimed a similar period to be some tenths of degree below the "previous" record. -
Riccardo at 09:30 AM on 22 December 2010Lindzen and Choi find low climate sensitivity
VeryTallGuy when you increase emission at the surface by increasing surface temperature you won't get the same excess energy leaving the planet at TOA, part of it will be absorbed by the atmosphere. To balance a forcing at TOA you need a larger temperature increase then predicted by this simple calculations. Basically, this is the same mistake made by RW1 before. -
adelady at 08:37 AM on 22 December 2010We're heading into an ice age
@186 I think you'll find that snow on Mt Wellington is hardly a Christmas novelty. -
kdfv at 08:30 AM on 22 December 2010We're heading into an ice age
#185 First ever recorded summer snow in Australia. Things are starting to get interesting now! -
Joe Blog at 06:51 AM on 22 December 2010Stratospheric Cooling and Tropospheric Warming - Revised
@HR: "I'm really interested why molecules are more likely to collide while IR and molecules aren't more likely to collide when CO2 is increased in the stratosphere?" They will collide whatever their state... but if they have less energy than what they collide with, they will absorb energy from the more excited molecule(excitation is normally referring to increased T/energetic excitation, kinetic motion of a molecule) And if they have more, the exchange is reversed. So if CO2 is radiating away more energy than its receiving via absorption, it will remove energy from the surrounding molecules... simple, the net flow of heat is from hotter to colder. -
VeryTallGuy at 06:42 AM on 22 December 2010Lindzen and Choi find low climate sensitivity
From the invariably excellent Science of Doom the 3.7 W/m2 is defined:"The change in net (down minus up) irradiance (solar plus longwave; in W/m2) at the tropopause after allowing for stratospheric temperatures to readjust to radiative equilibrium, but with surface and tropospheric temperatures and state held fixed at the unperturbed values."
Note"the stratospheric adjustment is minor"
so it's essentially the same as a top of atmosphere calc. Interestingly as noted in their post, applying this to the surface temperature does NOT seem to result in the 1.2 degrees warming: From the Trenberth link above: 1) radiative flux at the surface = 396W/m2 - equates to 289.09K blackbody temperature 2) Add 3.7 to that raises temperature to 289.76, so 0.65 degC temperature rise. 3) In order to get a 1.2 degC rise at the surface you need a heat flux increase to 402.6W/m2, so 6.6W/m2 at the surface. I'm not exactly sure how that calc is done to translate 3.7W/m2 TOA to 6.6 at surface, although you'd expect it to be larger so it seems about right. I can't find a reference for this calc - can anyone help? Are my sums right? -
muoncounter at 05:59 AM on 22 December 2010Greenland Ice Sheet outlet glaciers ice loss: an overview
#27: Your linked paper "Testing hypotheses of the cause of peripheral thinning" makes a distinction between land-terminating and ocean-terminating glaciers. There was a four fold increase in mean marine-terminating outlet glacier thinning rates ... between the periods 1993 to 1998 and 1998 to 2006, while thinning rates of land terminating outlet glaciers remained statistically unchanged. This suggests that a change in a controlling mechanism specific to the thinning rates of marine-terminating outlet glaciers occurred in the late 1990s and that this change did not affect thinning rates of land-terminating outlet glaciers. This distinction argues for warmer water contributing to melting, rather than a strictly "solar influence," as you seem to suggest in #28. Would not a solar influence affect land and ocean-terminating glaciers equally? And isn't ocean warming a known symptom of the GHE? -
Albatross at 05:28 AM on 22 December 2010The Climate Show #4: Peter Gleick, AGU and climate sensitivity
Another interesting show guys. Excellent work as always. It was nice having Peter Gleick on. Maybe having a prominent guest can become a feature. I really liked that Glen was playing devil's advocate regarding the "warm Arctic cold-continents" phenomenon that we seem to be seeing again this year. Perhaps a post on this needs to be done on this soon at SS. Merry Christmas guys. PS: This bird really misses cricket..sigh. -
Stephen Leahy at 04:19 AM on 22 December 2010A Merchant of Doubt attacks Merchants of Doubt
An excellent essay by Clive Hamilton on why people can't accept climate change despite the evidence: http://www.clivehamilton.net.au/cms/media/why_we_resist_the_truth_about_climate_change.pdf -
Ice data made cooler
Thanks again to all for reviewing my Vostok graph. I've added many of the suggestions made here: labels, y-scale markers, and a means of rescaling graphs. These were essential features. Other features will be added as I can find time to do so. jg -
archiesteel at 03:31 AM on 22 December 2010Stratospheric Cooling and Tropospheric Warming - Revised
@HR: "I'm really interested why molecules are more likely to collide while IR and molecules aren't more likely to collide when CO2 is increased in the stratosphere?" I'd like to answer this question, but it's so badly written I can't figure out what it means. Contrarians, please try to eschew obfuscation in your arguments. Thanks. -
archiesteel at 03:23 AM on 22 December 2010Stratospheric Cooling and Tropospheric Warming - Revised
@RSVP: "...at which point, the CO2 molecule cools." A more accurate description would be that it returns to its previous temperature. The extra amount of IR radiation is still in the system, therefore raising the temperature of the system until a new equilibrium is reached. Quod erat demonstrandum. "Furthermore, last time I checked, my pocket yields an interest rate of exactly 0.00000%" I am not interested in your incorrect analogies. Try logic instead. -
archiesteel at 03:19 AM on 22 December 2010Stratospheric Cooling and Tropospheric Warming - Revised
@RSVP: "I think Socrates had to down hemlock for this same accusation." Socrates used logic, and pursued a quest for truth, while you appear to engage in scientific sophistry designed to stall the debate on AGW. There really is no comparison possible. "So I take this as a compliment which I really do not deserve." It isn't a compliment, and you do deserve it. -
CBDunkerson at 00:23 AM on 22 December 20101934 - hottest year on record
prosch, actually the United States does show a warming trend... just a less pronounced trend than the global average.Moderator Response: The comment you're replying to was actually spam, albeit cleverly disguised to appear on-topic. -
Stratospheric Cooling and Tropospheric Warming - Revised
RSVP - Please, you've been on this website for quite a while, and know better than to treat this as a zero-sum fixed quantity issue. Energy comes in continuously from the sun, greenhouse gases slow the exit of that energy to space at any particular temperature (higher emission altitude, lapse rate from there to the ground, or just by looking at effective TOA emissivity), temperatures increase, and outgoing energy increases as well as the Earth system tries to balance in/out energy. Please stop with the inappropriate analogies, such as fixed amounts of change in your pocket (unworkable analogy, it doesn't reflect any aspect of the climate system). We've had that discussion before, on the "Waste Heat" thread, regarding the Bad Analogy logical error. -
Ned at 23:34 PM on 21 December 2010It's freaking cold!
I would argue that if we observe record low temperatures [...] Well, we aren't observing record low temperatures, as far as the whole Earth is concerned. Maybe some individual place is ... but there's nothing especially noteworthy about that. Maximiliano Herrera has compiled data on met stations that set new high or low records every year since 2002. When I last looked at his site, earlier this fall, 2010 had set 337 warm records versus 13 cool records. In 2009, the ratio was 80 (warm) to 15 (cool). In 2008, it was 40 (warm) to 18 (cool). In 2007, it was 133 (warm) to 9 (cool). And so on... -
michael sweet at 23:15 PM on 21 December 2010Greenland Ice Sheet outlet glaciers ice loss: an overview
Arkadiusz: It certainly is a difficult problem to predict what the great ice sheets will do in the future. Past records, including paleo records, are not comparable to the present forcing: the current forcing is much bigger. Models of sea ice in the arctic have greatly underestimated current ice melt (see the IPCC report). The great ice sheets are also starting to melt long before predicted. On the other hand, if you check my reanalysis link at #20, the current anomalies over Greenland are 10C higher than historic over the ice sheet and 5 degrees higher over the ocean. Do the papers you cited refer to anomalies this high, or were they not anticipated? Most of this winter has been over 0C over the southern ice sheet. This unprecedented heat must have some affect on the ice sheet. Do you wait until the ice sheet collapses before you acknowledge there might be a problem? The ice sheet will undoubtedly have some sort of lapse time before it fully responds to the heat. How long do we have? -
Arkadiusz Semczyszak at 22:48 PM on 21 December 2010Greenland Ice Sheet outlet glaciers ice loss: an overview
“direct and indirect - of solar activity.” For starters I recommend all the latest works Lockwood's (et all. of course) and especially (and “consistently”) Solar Influences on Climate (Reviews in Geophysics, 2010). If J.C. “dusting of” about this topic, I will present the latest (last 2-3 years) work - papers, showing the changes, feedback resulting from changes - in the TSI, UV, ULV, volcanic activity, magnetic, phytoplankton - ENSO - clouds - ozone, conductivity of the atmosphere, etc. ... -
Eric (skeptic) at 22:43 PM on 21 December 2010Lindzen and Choi find low climate sensitivity
RW1 (#132), thanks for explaining your numbers again. What doesn't seem to match Trenberth is the 80W/m^2 lost by evaporation (cooling) at the surface (plus another 17 for thermals). In your budget you only consider the energy radiated from the surface. Can you adjust your budget account for evaporation and thermals? Also like KR in 131 I am a little unclear on what you mean by "gain". You are saying that a certain amount of solar energy makes it to the atmosphere and surface (in Trenberth it is 341-79-23 which is about the same as your #'s) Then we measure the earth at 288K and calculate 390W emitted. You then define gain as the ratio of the solar energy caught in the earth/atmosphere (ok...) divided by surface radiation (doesn't make sense). Seems to me like you are comparing two fundamentally different numbers. -
Arkadiusz Semczyszak at 22:25 PM on 21 December 2010Greenland Ice Sheet outlet glaciers ice loss: an overview
All right ... In a “great” nutshell : For three years I deal with problem : „thinning rates of key Greenland outlet glaciers” - what is the effect and what is the cause ? According to this work: Greenland Ice Sheet Surface Mass-Balance Modeling in a 131-Yr Perspective, 1950–2080, Mernild et al. 2010. write: “The authors simulated an 90% increase in end-of-summer surface melt extent (0.483 × 106 km2) from 1950 to 2080 and a melt index (above 2000-m elevation) increase of 138% (1.96 × 106 km2 × days).” Most researchers claim that the outlet glaciers of Greenland (including those within the land) are very sensitive to even small temperature changes ("Arctic amplification"). Cited by me first work shows the difficulties in the interpretation of old data (Eemian). Other works show the great influence of the place and size of the snowpack (SnowModel) the movement of glaciers and the "thinning outlet" (see also: The Cryosphere Estimation of the Greenland ice sheet surface mass balance for the 20th and 21st centuries., Fettweis et al., 2008.) . Even so. “great warming” in Greenland of the 30s (according to many of Greenland's still bigger and more violent than at present) does not give answers, how would the glaciers. Then the loss of ice - the dynamics of movement of glaciers - was (30s) faster than at present, but in the 30's was negative phase of NAO and AO (now this are positive - of course, "most frequently"), concerned mainly the warming of spring, for now - autumn, etc. Her recent works are beginning to agree on one thing - it: “... highly sensitive to ocean Conditions ..." decide on the melting and traffic of Greenland's glaciers (not just those “ending” in the sea? - Testing hypotheses of the cause of peripheral thinning of the Greenland Ice Sheet: is land-terminating ice thinning at anomalously high rates? Sole et al., 2008.). Yes: highly sensitive - the temperature - "thinning rates of Greenland Outlet Glaciers key"- a very affects the movement of glaciers across Greenland. However, with mass loss of glaciers is increasingly important that the surface of Greenland's mountainous sculpture, geothermal activity. Glaciers are to be retained in the narrow mountain valleys, narrow valleys, fjords. For this walk "... negative feedback mechanisms ... " Conclusion. The loss of ice in Greenland is not (and will) linear with respect to temperature. We do not know whether an increase in snow accumulation will be the east or west (various atmospheric circulation, different topographic features) and this will have a decisive influence on the flow of glaciers into the sea: „The greatest difference in melt extent occurred in the southern part of the GrIS, and the greatest changes in the number of melt days were seen in the eastern part of the GrIS ( 50%–70%) and were lowest in the west ( 20%–30%).[ Mernild et al. 2010.]” Mernild et al. 2010., saying: „The rate of SMB loss, largely tied to changes in ablation processes, leads to an enhanced average loss of 331 km3 from 1950 to 2080 and an average SMB level of −99 km3 for the period 2070–80.” - may be wrong. The continental glaciers 2,080 years, particularly those from the deep interior of Greenland will be stable because such accumulation of snow will stop them. These coastal (eg Jakobshavns, Helheim) BTW much farther from the sea and - in this way - lose its dynamic ... P.S. A thorough knowledge of the PETM may tell us all - and the issue about of Greenland ice ... -
Alec Cowan at 22:09 PM on 21 December 2010Stratospheric Cooling and Tropospheric Warming - Revised
@RSVP #72 I knew, as I called that paragraph A. Again, I insist you to start by explaining what UNEXCITED means in A. When you get it you'll comprehend the error in your initial thoughts ... if you're looking for knowledge. I want you to know that your comments are extremely valuable to me for educational purposes. I'm making a collection of your comments for some of my students to work on them during 2011. -
scaddenp at 20:53 PM on 21 December 2010Lindzen and Choi find low climate sensitivity
" but it's assuming all of the absorbed 3.7 W/m^2 affects the surface - meaning all of it is re-radiated downward, instead of only half. " As others have pointed out, this is not true. The calculation used to arrive at 3.7W/m2 assume nothing of the kind and physically the situation is different. The number cannot not be used in the way you describe. See the definition in 2nd IPCC report. Essentially the same set of equations are used to calculate the added energy flux at the surface due to increased but its different no. From memory its about 3.5W/m2 for current GHG emissions since pre-industrial but I dont know the figure for doubling. -
Paul D at 20:45 PM on 21 December 2010Stratospheric Cooling and Tropospheric Warming - Revised
RSVP: "If I move a dollar from one pocket to another all day as I go window shopping, my buying power hasnt changed." The US government isn't printing trillions and trillions (etc) of dollars per second all day. The Sun however... Your discussion is centred around a fixed energy scenario where there is no further input of energy. Even in the scenario you suggest no energy is lost, which is the point. The only way for the energy can escape is to be radiated to space eventually. To be honest your silly game is juvenile. -
RSVP at 19:57 PM on 21 December 2010Stratospheric Cooling and Tropospheric Warming - Revised
Alec Cowen #52 "I suggest you to start by explaining what "unexcited" means in A. " Sorry, this was a quote from the featured article.
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