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chriskoz at 22:00 PM on 25 February 2012Radiative Balance, Feedback, and Runaway Warming
Fantastic article. Now I can realy see the GH effect in much better perspective. Few questions jump: Are those curves a true representatives of our real earth or just exemplary? If the former, can we say by how much the green and red horiz lines are appart when comparing recent solar energy with meander minimum during LIA? Then, what are the angles of intersection of red curve (CO2 only) and blue curve (CO2+H2O) with the current solar radiation line? Finally, if red curve represents 400ppmCO2 we have right now how far above the 280ppm curve would be? I'm asking those questions, because I want to have the feeling about the relative magnitude of the three forcings (solar, CO2 & H2O) we are talking about in this model. Thanks. -
Paul D at 20:48 PM on 25 February 2012Radiative Balance, Feedback, and Runaway Warming
Good article. -
Bernard J. at 20:45 PM on 25 February 2012Global Extinction: Gradual Doom as Bad as Abrupt
I'm late to this thread, so others (especially Glenn Tamblyn) have already said what I will below, but I feel that it bears repeating with a slightly different emphasis. With respect to Malthus, Club of Rome, the Ehrlichs and similar, it is important to recognise, as Glenn and Adelady and others already have, that technology simply delayed the anticipated consequences of human population growth and societal complexity. The various resource limitations do still exist - they've simply been moved to a different timeframe through energy and technology use. After all, what technology will actually sustainably quench the world's huge and growing thirst for water? What technology will actually sustainably assuage the world's huge and growing hunger for meat, for timber, for the very space and topsoils that are used to grow such resources and much more? How will such future technologies be sustainably energised? Sorry owl905, but I'm with my ecological colleagues' (and Albert Bartlett's and Joseph Tainter's, amongst others) consensus on this matter. And all that technology about which you speak is coming with huge collateral damage, and it's largely because (most) humans don't live in the Arctic, or in a disappearing rainforest, or 100 metres underground in an aquifer, that they don't understand the cumulative damage to the biosphere that is occurring. When all is said and done it boils down to basic thermodynamics, and one of the thermodynamic penalties of humanity's co-opting of the planets' energy/resource systems will be that the bottoming-out, when it inevitably comes, will be all the more severe. Essentially, we've made a Faustian bargain in order to avoid paying the piper. As Glen observed in his post at #15, no technology currently in existence will allow humanity to avoid those thermodynamic consequences. Similarly - and here I am forced to differ somewhat with Glenn's otherwise excellent post - it is extremely difficult to see how a possible "future technology certainly could" enable humans to avoid the huge entropy imbalance that we've inflicted on the planet's life support systems, whether one is speaking agriculturally or ecologically. The numbers do not add up, and certainly not if future (larger?) human societies are to be equitable. If anything our technological trajectory seems to describe the thermodynamic equivalent of the story of the old woman who swallowed a fly... For this reason I am not a technofixophile. Not by itself, and not with the numbers of humans that we have on the planet. If we had at least an order of magnitude fewer people, and if we had a system that doesn't encourage the gross inequity and cavalier waste that we see in our societies, then perhaps our technology could catapult us toward what is currently science fiction, but in some cases even that would require skirting around the current laws of physics that dictate the ultimate finiteness of the resources available to us. And before someone puts their hand up at this point and mentions interstellar (or even interplanetary) travel, please calculate the energy and time requirements to successfully and productively achieve such, or point to the particular laws that might be circumvented in order to bring those otherwise literally astronomical numbers within reach of human endeavour. There's also the fact that our ever more sophisticated technologies, as the complex systems that they are, are vulnerable to disruptions. The more complex, the more that can go wrong, and in the case of serious failure, the more difficult it can be to recover. This is the stuff of whole threads though - indeed, of whole disciplines - and it's wandering from the basic subject of this thread, so I won't head down that path at the moment. And in case any readers here missed them, Tamino had a couple of interesting threads in the vein of this thread: http://tamino.wordpress.com/2012/01/04/what-is-epsilon http://tamino.wordpress.com/2012/01/23/best-case-scenario/ -
Doug Hutcheson at 19:54 PM on 25 February 2012Radiative Balance, Feedback, and Runaway Warming
So obvious, once clearly explained. Thank you, Chris. -
Rob Painting at 18:34 PM on 25 February 2012Clouds provide negative feedback
DSL - Strange how the Earth still got very hot in the past eh? The most likely explanation is that the lowering of cloud height is related to the ENSO trend, and the consequent top-of-the-atmosphere radiation flux over the last decade. The decade started off with weak La Nina and El Nino and finished off with strong ones, and the end of the decade was La Nina-dominant. A colder, drier atmosphere (relative to the beginning of the decade) should see less cloud formation and a lowering of cloud height. Nothing makes sense in mainstream media land, because they don't even make the effort to understand what's happening. Sad really. I'm writing up a post/rebuttal of Davies & Molloy (2012). Their findings have predictably been mangled - although a sentence in the study doesn't help. -
Steve L at 18:27 PM on 25 February 2012Radiative Balance, Feedback, and Runaway Warming
This is a fantastic explanation. I had spent a little bit of time thinking about this problem, but now reading this post I realize I didn't yet have the information needed to reason this through. Thanks! -
RonManley at 17:28 PM on 25 February 2012Scafetta's Widget Problems
First, thanks for the positive comments. I did consider the El Nino index (e.g. Extended MEI) but data for it don't go back as far as the AMO. I could have included both MEI and AMO but while it might have added something to the accuracy it would have added little to the understanding of climate. I could also have included other measures of greenhouse gases. Basically my simple regression model has shown that if you include CO2 and a climate cycle you can simulate temperatures quite accurately. Using CO2 as an independent variable is more justified than using either the MEI or AMO. CO2 is a recognised forcing factor. The cycles/oscillations are not and it would not be legitimate for the IPCC to use them input in their models. -
David Lewis at 16:59 PM on 25 February 2012Satellites find over 500 billion tons of land ice melting worldwide every year, headlines focus on Himalayas
Hansen, Earth’s Energy Imbalance and Implications, states that 1 Watt-yr over the full Earth surface corresponds to about ~1.61 x 1022 Joules. He infers that the Earth’s energy imbalance over the period 2005 – 2010 was 0.58 W m-2. He estimates that over a full solar cycle the figure would be somewhat greater, about 0.75 W m-2. Converting to Joules, I get 0.75 W m-2 = 1.2 x 1022 Joules. In comparison, he summarized his understanding of the data in his preferred sources in the literature for absorption of heat by ice on land, where "most of the energy is used in the phase change from ice to water" in this (Figure 8c) chart: Which appears to show a total of about a bit more than ~0.02 W m-2 worth of heat going into land ice by 2006 - 2007 or so. Its a massive amount of heat compared to what I use to boil coffee in the morning, but if it is compared to the heat that is accumulating each year in the planetary system, which goes primarily into the oceans, it is less than 3%. Convert that into Joules, and it seems you have 3.22 x 1020 Joules. -
muoncounter at 16:46 PM on 25 February 2012Tree-rings diverge from temperature after 1960
cjs#65: It's the same article. And it still is off-topic. See CO2 is plant food. Let's try less selective quote-mining and more reading for content. -
DSL at 15:45 PM on 25 February 2012Clouds provide negative feedback
ABC (Aussie) has a summary of Roger Davies (et al.) work on cloud height decrease over the last decade. From the summary: "Experts from the University of Auckland suggest the change in cloud altitude could be the Earth's way of dealing with global warming." Earth's way of dealing with global warming. We don't need mitigation; Earth's got our backs. Earth's a smart cookie. It likes us. Wants to protect us. That Pluto . . . dumb as a rock . . . living way out there at the edge . . . freezing! Isn't even smart enough to grow a coat. -
IanC at 15:38 PM on 25 February 20122nd law of thermodynamics contradicts greenhouse theory
@1297 Yogi, When I talked about the OLR graph in #1290, I said "the radiation coming from the surface", not radiation coming from CO2 near the surface. When you are looking down in the 600-750 band, you are seeing the emission from CO2 at the level near the detector. Using a standard lapse rate of 6.5 degrees, at 3 km, the brightness temperature should be about 19.5 lower than the surface temperature, so the dip will be relatively small. Using the standard atmosphere at 3km looking down, that is about right (it'll be clearer if you turn off water vapour, which tends to distort the top of the spectra). The closer you get to the surface, the less temperature contrast between the surface and the air temperature near the "instrument", and so the dip will be smaller. Now for clouds it appears to radiate as a black body. If you are on the surface looking up, you are effectively seeing the bottom, and if you are using heavy cloud/rain, the cumulus base is at 0.66km. The temperature on the surface is 288K, so lapse rate of 6 degree puts you at 284k at the base. that looks about right from the spectra. If you look closely at the 600-750 band you'll see a slight bump, since there you are actually detaching radiation from CO2 near the ground, which is warmer. When you are looking down at 20km, having cloud is effectively like having a surface that is cooler. If you compare the case without cloud, and altostratus at cloud top at 3km, you'll expect a change in brightness temperature in the 800-1000 band by about 20 degrees, and that is exactly what you'll get. -
cjshaker at 15:19 PM on 25 February 2012Tree-rings diverge from temperature after 1960
This article from Columbia University says the opposite, that trees next to the Tundra are thriving “I was expecting to see trees stressed from the warmer temperatures,” said study lead author Laia Andreu-Hayles, a tree ring scientist at Columbia University’s Lamont-Doherty Earth Observatory. “What we found was a surprise.” http://www.ldeo.columbia.edu/news-events/trees-tundras-border-are-growing-faster-hotter-climate Chris Shaker -
Bob Lacatena at 15:07 PM on 25 February 20122nd law of thermodynamics contradicts greenhouse theory
1299, Yogi, Why is that, do you think? -
muoncounter at 14:42 PM on 25 February 2012Tree-rings diverge from temperature after 1960
cjshaker#63: Your link has nothing to do with the 'divergence problem,' although there is a passing mention of it. This is clear evidence of warming. But it is not good news: The outlook may be less favorable for the vast interior forests that ring the Arctic Circle. Satellite images have revealed swaths of brown, dying vegetation ... Evidence suggests forests elsewhere are struggling, too. In the American West, bark beetles benefitting from milder winters have devastated millions of acres of trees weakened by lack of water. -
owl905 at 13:46 PM on 25 February 2012Global Extinction: Gradual Doom as Bad as Abrupt
@adelady 26 "And what technology was that specifically? It was converting oil into fertiliser." You're kidding, right? Every aspect - information, science, remote sensing, biology, chemistry, education, finance, management ... there's no end to the technology paradigm - the period since the mid-70s is soaked in every aspect of technology invention and innovation imaginable. To make any claim that it is nothing more than oil into fertilizer in the agriculture world is Guinness-level myopia. -
cjshaker at 13:44 PM on 25 February 2012Tree-rings diverge from temperature after 1960
Regarding tree ring proxies and the divergence problem, this paper claims that some trees such as western juniper are growing more rapidly in response to elevated CO2 http://libres.uncg.edu/ir/uncg/listing.aspx?id=7935 Chris Shaker -
owl905 at 13:41 PM on 25 February 2012Global Extinction: Gradual Doom as Bad as Abrupt
@Glen - very sad response from you. ClubofRome 'wasn't about technology' was because it was the factor they missed. You missed it as well. And no, it doesn't "just change the timing". You fall on your facia with the Punjab as an example that isn't about technology - while you acknowledge all the technology used to make it succeed. Technology isn't succeeding "only by accelerating our draw-down of resources". That's fictional nonsense. After that you drift into a philosophical ambiguity that's unfounded by observation. The fundamental fallacy is yours; your response highlights an attempt to dance around while failing to deal with it. -
cjshaker at 13:35 PM on 25 February 2012Medieval Warm Period was warmer
Also, this AGU published research paper, "Evidence for a ‘Medieval Warm Period’ in a 1,100 year tree-ring reconstruction of past austral summer temperatures in New Zealand". http://ruby.fgcu.edu/courses/twimberley/EnviroPhilo/CookPalmer.pdf Chris Shaker -
YOGI at 13:32 PM on 25 February 20122nd law of thermodynamics contradicts greenhouse theory
#1298..But more interesting is that OLR (in the 600-750 band) from 20km is always the same regardless of location and temperature on this model: http://forecast.uchicago.edu/Projects/modtran.html -
cjshaker at 13:30 PM on 25 February 2012Medieval Warm Period was warmer
I've always thought of the Medieval Warm Period as an example of Natural Variability. Found some examples of other proxy data being used for temperature reconstructions Woods Hole Oceanographic Institution Examines 2,000 years of sediment records for temperature reconstruction "A new 2,000-year-long reconstruction of sea surface temperatures (SST) from the Indo-Pacific warm pool (IPWP) suggests that temperatures in the region may have been as warm during the Medieval Warm Period as they are today." "Water temperature during the late Medieval Warm Period, between about A.D. 1000 to 1250, was within error of modern annual sea surface temperatures. (Oppo, Rosenthal, Linsley; 2009)" http://www.whoi.edu/page.do?pid=7545&tid=282&cid=59106&ct=162 Found another interesting page about sediment record analysis at Woods Hole, covering the Medieval Warm Period and the Little Ice Age http://www.whoi.edu/oceanus/viewArticle.do?id=3842 "Events warmer than today occurred about 500 and 1,000 years ago, during the Medieval Warm Period, and it was even warmer than that prior to about 2,500 years ago." "Because the Sargasso Sea has a rather uniform temperature and salinity distribution near the surface, it seems that these events must have had widespread climatic significance. The Sargasso Sea data indicate that the Medieval Warm Period may have actually been two events separated by 500 years, perhaps explaining why its timing and extent have been so controversial. Second, it is evident that the climate system has been warming for a few hundred years, and that it warmed even more from 1,700 years ago to 1,000 years ago." This graph of the Sargasso Sea Surface Temperature, reconstructed from sediment cores, shows what they are talking about http://www.whoi.edu/oceanus/viewImage.do?id=8722&aid=3842 More data on reconstructed temperatures around the world from the Medieval Warm Period is available at the Woods Hole web page. Go there and search for 'Medieval Warm Period' http://www.whoi.edu/search.do?q=Medieval+Warm+Period&g=ext&search=Search&type=search Paper offering high resolution temperature proxy data from an Alaskan lake over the past 6,000 yrs, derived from midge analysis on the sediments. Shows temperatures there were higher in the past 3,000 yrs than today"Although the Moose Lake TJuly record displays an increasing trend over the past 150 years, the TJuly values in several warm intervals of the past 6000 years were comparable to or exceeded early 20th-century values. For example, the TJuly values during the MCA were generally higher than the early 20th-century values (Fig. 4C). " http://www.life.illinois.edu/hu/publications/Clegg_et_al_2010.pdf Chris Shaker -
owl905 at 12:49 PM on 25 February 2012Satellites find over 500 billion tons of land ice melting worldwide every year, headlines focus on Himalayas
Correction from 18 - it shouldn't say 'all of that heat' ... unsure what the right reference point is ('energy', 'cooling factor'?). -
owl905 at 12:23 PM on 25 February 2012Satellites find over 500 billion tons of land ice melting worldwide every year, headlines focus on Himalayas
@Charlie A - if you can't join the dots between the TAR graph and the AR4 statement that there's less than a 10% divergence from that graph by century's end, I'm not sure finding a graph that looked visually like the TAR would satisfy you. -
owl905 at 12:20 PM on 25 February 2012Satellites find over 500 billion tons of land ice melting worldwide every year, headlines focus on Himalayas
@ Spherica 1 "Ten years of that and you've raised the temperature of the top meter of the ocean by a full degree." At the detail level, why is there an implied assumption that all of that heat will get from the glaciers and sheets to the surface layers of the ocean? In the bigger picture, surface layers of the oceans have been stable during this period. Likewise lower troposphere temperatures. Much faster rises in the 90s were in a world with greater exposures of all forms of permanent ice at lower latitudes and altitudes. If anything, the clues could claim an even greater dropoff in warming for this 00s. The true value of GRACE monitoring is to get a real established baseline for the ice sheets. Maybe the pro-pollutionists will spend less time trying to fake a 'not happening' comment. -
MarkR at 12:19 PM on 25 February 2012Satellites find over 500 billion tons of land ice melting worldwide every year, headlines focus on Himalayas
#1 Sphaerica #13 Eric (skeptic) Thanks for your comments guys, I re-ran my calculations and found out where I'd gone wrong. The graph and comments relating to the graph have been corrected and a note added to the post. An embarrassing mistake on my part, I corrected it as soon as possible and I hope you'll all accept my apologies. -
Charlie A at 12:14 PM on 25 February 2012Satellites find over 500 billion tons of land ice melting worldwide every year, headlines focus on Himalayas
@owl905 #15: thanks, but both your ref and everything in AR4 WG1 Ch 10.6 mention only the projection to 2090-2099 decade. I have also found some short term projections for steric rise vs. emission scenario, but no projections for GMSL before 2090. Surely I'm just overlooking something and AR4 has short term projections that can be used to generate figures such as Fif 2 of this SkS post. The SkS author listed Allison et al, 2009 as the source, without further detail. Allison 2009 is the Copenhagen Report, which is not a peer reviewed article and seems to reference TAR, not AR4, even though it was written two years after AR4. Figure 2 is a comparison of IPCC projections vs. observations. Surely there is something more up to date than a 2009 comparison to TAR. -
owl905 at 11:55 AM on 25 February 2012Satellites find over 500 billion tons of land ice melting worldwide every year, headlines focus on Himalayas
@Charlie 11 "Model-based projections of global average sea level rise at the end of the 21st century (2090–2099) are shown in Table SPM.3. For each scenario, the midpoint of the range in Table SPM.3 is within 10% of the TAR model average for 2090–2099. The ranges are narrower than in the TAR mainly because of improved information about some uncertainties in the projected contributions.[15] {10.6} " http://www.ipcc.ch/publications_and_data/ar4/wg1/en/spmsspm-projections-of.html -
YOGI at 11:20 AM on 25 February 20122nd law of thermodynamics contradicts greenhouse theory
Sphaerica#1296 "I have no idea what this means. What is the "it" in "it has no effect..."? Greenhouse gases?" I`m saying on the 20km looking down, you cannot see the 600-750 band any more when the sub-Arctic reaches -30C. But more interesting is that OLR from 20km is always the same regardless of location and temperature on this model: http://forecast.uchicago.edu/Projects/modtran.html -
MarkR at 11:17 AM on 25 February 2012Satellites find over 500 billion tons of land ice melting worldwide every year, headlines focus on Himalayas
#13 Eric: I think I made an error. I'll double check tomorrow and correct the graph if so. I think I might have multiplied the annual loss rate by 8 (i.e. I used total ice loss rather than annual, and added that each year). I'll double check, but if so that's horribly horribly embarassing! -
YOGI at 11:03 AM on 25 February 20122nd law of thermodynamics contradicts greenhouse theory
IanC#1290 "As for your question, in the OLR (20km looking down) graph and at regions without atmospheric absoprtion, you will be seeing radiation coming from the surface, which is ~265K. For the DLR in the 600-750cm-1 band, the radiation is coming from CO2 near the surface, which is again close to 265K." But if I look down from 3km, the 600-750cm-1 band barely shows up, and looking down from 1km its not there at all, that does agree not with most of this being due to near surface CO2. And looking up from the surface with heavy cloud/rain, all bands are radiating, but when looking down from 20km, the difference between clouds/no clouds is minor in comparison. -
Eric (skeptic) at 10:54 AM on 25 February 2012Satellites find over 500 billion tons of land ice melting worldwide every year, headlines focus on Himalayas
Am I reading figure 5 correctly? As Sphaerica pointed out the heat needed to melt 500 Gt of ice is about 1020 J, but the chart shows about 1021 J per year which is about an order of magnitude more. In perspective http://en.wikipedia.org/wiki/Orders_of_magnitude_%28energy%29 that amount of energy is less than annual human energy consumption and two orders of magnitude less than the daily incident solar radiation. -
muoncounter at 10:34 AM on 25 February 2012Satellites find over 500 billion tons of land ice melting worldwide every year, headlines focus on Himalayas
Doug H: See the thread Greenland ice loss continues to accelerate. And you're quite right, the GRACE system is very cool. -
Charlie A at 10:13 AM on 25 February 2012Satellites find over 500 billion tons of land ice melting worldwide every year, headlines focus on Himalayas
Does anybody have an equivalent to Figure 2 that uses AR4 projections rather than TAR, and which has current observations? -
Doug Hutcheson at 09:56 AM on 25 February 2012Satellites find over 500 billion tons of land ice melting worldwide every year, headlines focus on Himalayas
Does GRACE give us sufficient resolution to determine if the rate of global ice loss is slowing, steady, or increasing? I would expect the rate to increase over time, as global surface temperatures rise and ice mass decreases, but with significant noise over the signal (as is seen in and possibly tracking with global temperature records). It will be interesting to see if a steady or increasing rate of melt is reflected in AR5. I am still enough of a kid to look at science like the GRACE program and say "Gee ... that's pretty neat! Measuring mass on Earth indirectly, by measuring the distance between two satellites travelling in formation ... someone really smart thought that one up!" ... then I look at how some other really smart people are using their extraordinary gift of human intelligence purely to undermine popular confidence in the results of such science and the warm glow fades from my heart. -
Nick Palmer at 09:53 AM on 25 February 2012Scafetta's Widget Problems
These "cyclical variations explain the warming/lack of warming" theories remind me of the biorhythms fad of the 70s. The use of the cycles (to explain climate variation) by so called scientists is really just like seeing imagined patterns in Rorschach ink blots. -
Mike3267 at 09:26 AM on 25 February 2012Search For 'Missing Heat' Confirms More Global Warming 'In The Pipeline'
Thank you KR! -
MikeS at 09:10 AM on 25 February 2012Satellites find over 500 billion tons of land ice melting worldwide every year, headlines focus on Himalayas
It is interesting to see that another significant property of ice i.e. its large latent heat of fusion is getting more attention. This point has often been highlighted by James Lovelock but I have not seen its implications discussed much on any 'climate blogs' until now. Although the Arctic has its annual melt/freeze cycle we can expect this to change with the global warming trend, with the refreezing over autumn/winter taking longer as the stored heat from the previous summer has to be removed. I think this is what we have seen in the northern hemisphere over the last few years and is clearly depicted in this post on Climatecrocks Arctic Anomaly I think we could even coin a new acronym - AAPCA - Annual Arctic Phase Change Anomaly. Well done to John and colleagues on running such a good science based site. I notice even here it's names like Heartland and Monckton that attract the most comments, unfortunately. -
Bob Lacatena at 09:04 AM on 25 February 20122nd law of thermodynamics contradicts greenhouse theory
1294, Yogi,...so in the sub-Arctic it has no effect on OLR when surface temp`s are -30C or lower.
I have no idea what this means. What is the "it" in "it has no effect..."? Greenhouse gases? A basic element of radiation, as evidenced by Stefan-Boltzmann, is that temperature plays a huge role. So for a few months of the year, temperatures are around 243˚K, radiation is only 198 W/m2. Conversely, when the sun is above the horizon, temperatures are around 273˚K and radiation is about 315 W/m2. While there is a huge difference between summer and winter, and between poles and tropics, I don't think anything qualifies for the statement "has no effect." But the spherical nature of the planet influences climate in a variety of other ways, as well, such as the spread of incoming sunlight over a larger area near the poles, the circulation of heat and moisture from the tropics through advection in the atmosphere, and other factors. It's not simple. It's not impossible to untangle, but not simple. -
muoncounter at 08:38 AM on 25 February 2012Satellites find over 500 billion tons of land ice melting worldwide every year, headlines focus on Himalayas
MarkR#5: "as it warms it emits more and acts to cool." If that was the entire system, wouldn't we be guaranteed stable temperatures? More realistically, as it warms, there's also more evaporation and thus more water vapor available to trap energy. And a larger area of ocean is exposed due to ice melt each summer, there's more open ocean to absorb solar input. -
logicman at 07:09 AM on 25 February 2012Satellites find over 500 billion tons of land ice melting worldwide every year, headlines focus on Himalayas
Just so as to ensure that nobody misunderstands the numbers below: caveat: there is no direct connection between human heat emissions and ice melting. The numbers are merely shown so as to give a sense of scale. Each year the Arctic ice retreats and then regrows. The problem is that it has not been regrowing as much as it has been melting. Here are some figures for the amount of heat it takes to melt the net lost ice. To melt the additional 280 km3 of sea ice, the amount we have have been losing on an annual basis based on PIOMAS calculations, it takes roughly 8.6 x 1019 J or 86% of U.S. energy consumption. Perspective: Ice Loss and Energy -
IanC at 07:08 AM on 25 February 20122nd law of thermodynamics contradicts greenhouse theory
Yogi, The graphs in the SkS article is data from arctic, where water vapour content is relatively low. Between 8-13μm water does aborb IR slightly, so if you are in a moist atmosphere it will alter the picture. Below is a comparison between DLR at arctic vs tropics. You can see from the curve for the tropics there is actually significant emission between 8-13 μm due to water vapour. You said:And the atmosphere emits IR brightly from 7.5 to 40 microns
Now brightness is relative, so it obviously depends on the application. What is dim in atmospheric science may not be dim for astronomy. From your source, they classify the emission at 3-4 micron as low. If you extrapolate the black body curves all the way out to 4 micron, or 2500cm-1, you'll see that the radiance between 8-13 micron is in fact quite high in the case of a tropical atmosphere. Infrared windows do exist, but that depends on how dry the atmosphere is, and what application you have in mind. -
YOGI at 07:07 AM on 25 February 20122nd law of thermodynamics contradicts greenhouse theory
Sphaerica#1291 Interesting so in the sub-Arctic it has no effect on OLR when surface temp`s are -30C or lower. http://forecast.uchicago.edu/Projects/modtran.html -
Search For 'Missing Heat' Confirms More Global Warming 'In The Pipeline'
Mike Total top of atmosphere (TOA) global imbalance is usually inferred from the various components, as there aren't any satellite resources doing direct differencing between incoming and outgoing radiation (quite difficult to do, given in particular spatial variations). Spectral changes in Earth emission, on the other hand, are very easy to measure. Over time, the relative energy in the Earth emission spectra, as per Harries 2001 and others, has shown decreases relative to the rest of the spectra at just the wavelengths expected for increased GHG absorption. That can be measured as changes on a single instrument, as the spectra will differ. Also, that can be observed at any point on the planet as a consistent local measure. It's really the difference between relative values on either the same or similar instruments, versus global sums. -
Biophilia at 06:47 AM on 25 February 2012Satellites find over 500 billion tons of land ice melting worldwide every year, headlines focus on Himalayas
Many people I have the pleasure of interacting with, assume very naively that because temperature increase to date has been less then a degree there's really not that much to worry about. There's no cause to reform our current economy. If only they understood the bigger picture and could grasp the importance of calculations like these, which give a sense of the planet's limited, one-time ability to buffer warming from our emissions. It's shaping up to be a riveting real life science fiction horror. If our present situation was fiction rather than reality it would make one hell of a sci-fi blockbuster. It's just happening a little too slow to hold the audience's attention. Despite some of the valid dislike of Gore because of his hypocritical talk vs. personal walk, his analogy of the frog in the pot of water, is playing out to a T in reality. Half of the people in the world seem content to sit and find out if the water really will get hot enough to kill. -
YOGI at 06:25 AM on 25 February 20122nd law of thermodynamics contradicts greenhouse theory
YOGI#1292 IR telescopes not radio telescopes -
Mike3267 at 06:21 AM on 25 February 2012Search For 'Missing Heat' Confirms More Global Warming 'In The Pipeline'
Painting wrote: "Because this planetary heat imbalance is tiny compared to the energy coming in from the sun, and the heat being radiated back out to space, it is too small to be measured directly by satellites." But I found this claim elsewhere on SkS: "In 1970, NASA launched the IRIS satellite measuring infrared spectra. In 1996, the Japanese Space Agency launched the IMG satellite which recorded similar observations. Both sets of data were compared to discern any changes in outgoing radiation over the 26 year period (Harries 2001). What they found was a drop in outgoing radiation at the wavelength bands that greenhouse gases such as CO2 and methane (CH4) absorb energy. The change in outgoing radiation was consistent with theoretical expectations. Thus the paper found "direct experimental evidence for a significant increase in the Earth's greenhouse effect". This result has been confirmed by subsequent papers using data from later satellites (Griggs 2004, Chen 2007)." http://www.skepticalscience.com/empirical-evidence-for-global-warming.htm Can someone help me reconcile these statements? -
Jeremy C at 05:56 AM on 25 February 2012Monckton Misrepresents Specific Situations (Part 2)
I notice on Monckton's WUWT response is that he seems to have learnt since his abysmal reply to Abraham. I remember his reply to Abraham as being easily disposable but here he pulls off sleight-of-hand after sleight-of-hand that allmost seem reasonable till you ask yourself about the assumptions and presuppositions he displays. It seems sceptical science has made him work harder which is a plus but I think it might become harder to displace his style in the public square. -
YOGI at 04:59 AM on 25 February 20122nd law of thermodynamics contradicts greenhouse theory
OK in the absorption bands, ingoing and outgoing IR is absorbed, radio telescopes can`t see out through them. Quote; your article: "In the "infrared window" of the atmosphere, the atmosphere is transparent. In these frequencies, no radiation is absorbed, no radiation is emitted, and here is where IR telescopes and microwave sounding satellites can look out to space, and down to the surface, respectively." IR is emitted in the "infrared window",the 20kn downward view shows it emitting 268K in the window (away from the absorption bands). And the atmosphere emits IR brightly from 7.5 to 40 microns: "The Earth's atmosphere causes another problem for infrared astronomers. The atmosphere itself radiates strongly in the infrared, often putting out more infrared light than the object in space being observed. This atmospheric infrared emission peaks at a wavelength of about 10 microns (micron is short for a micrometer or one millionth of a meter). So the best view of the infrared universe, from ground based telescopes, are at infrared wavelengths which can pass through the Earth's atmosphere and at which the atmosphere is dim in the infrared. Ground based infrared observatories are usually placed near the summit of high, dry mountains to get above as much of the atmosphere as possible. Even so, most infrared wavelengths are completely absorbed by the atmosphere and never make it to the ground." http://www.ipac.caltech.edu/outreach/Edu/Windows/irwindows.html -
MarkR at 04:50 AM on 25 February 2012Satellites find over 500 billion tons of land ice melting worldwide every year, headlines focus on Himalayas
2. actually thoughtful - the point I'm making is that a HUGE amount of heat has been absorbed over the past decade and concentrating on atmospheric temperatures, whilst popular for 'skeptics' is not what a proper skeptical scientist would do. A real skeptic would look at everything, not just cherry pick individual data. There's a really easy mistake to make though: if there were no ice at all and we had the same heating that we've had for 2003-2010 then the atmosphere wouldn't actually warm by ~2 C. It would warm by much less, because as it warms it emits more and acts to cool. To calculate the warming you have to use the heating imbalance in W m-2, which is about 0.1 W m-2 for the heating. That's actually very small, less than a tenth of a degree of warming by the time it balances out. -
Dave123 at 04:49 AM on 25 February 2012Satellites find over 500 billion tons of land ice melting worldwide every year, headlines focus on Himalayas
I've been wondering why there hasn't been a denier meme that runs like this: So 90% of the heat goes into the oceans and may be melting glaciers... that saves us from global warming. We'll run out of fossil fuels before we can overwhelm the natural buffers to the system. You warmists are worried for nothing. (these being the people who are happy watching other people drown). -
WheelsOC at 04:43 AM on 25 February 2012Satellites find over 500 billion tons of land ice melting worldwide every year, headlines focus on Himalayas
Sounds like critical information for AR5. One of the early caveats about AR4 was the lack of information about how melting ice would impact sea level rise, keeping their projections for the future relatively low. Just be sure I've got this totally straight. Over the study period: *Globally, the net change in land ice is about -500 billion tons per year? Every couple of years we wound up with a trillion tons of total glacier mass less than before? *The Antarctic as a whole is undergoing a net loss of land ice at a pace that's very similar to Greenland?
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