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Comments 26 to 50 out of 53:

26. h-j-m at 02:49 AM on 20 November, 2010
    muoncounter, my point is simple. Repeatedly there are statements made claiming that rising ocean temperatures provide evidence for the anthropogenic global warming theory. Now, let's have a closer look. The logical consequence of this claim is that rising atmospheric temperatures (due to anthropogenic global warming) causes rising ocean temperatures. There are two ways this could happen: Either the warmer atmosphere actively warms the underlying oceanic waters or the energy transfer from the oceans to the atmosphere via evaporation (latent heat) is slowed down. For the first possibility I have not seen any evidence presented so far while the second possibility directly contradicts the implied main positive feedback mechanism (more evaporation causing an increased green house effect of warming). A simple lab experiment could be conducted to prove (or disprove) the possibility to increase water temperature via warmer air above. Create a water column of let's say of 10 m perfectly insulated at the sides and the bottom. Lower a strip with temperature sensors (equally spaced to measure the downward propagation of heat) into that column that is adjustable so that the first measurements will occur just below the water surface (to allow for evaporation losses) and expose the water surface to a (monitored and controlled) warmer layer of air. Now let's say we consider a rise in temperature of 0.05 C at 2 m below the water surface significant that then will be the end point of the experiment. If the sensor indicating 2 m below surface hits the bottom of the container before that it should be considered a disprove. Else you have a partial success and data (energy usage, propagation speed of heat etc.) to start calculations how these findings relate to the reported warming of the oceans.
27. KR at 02:58 AM on 20 November, 2010
    h-j-m - Actually, increased CO2 directly increases the backradiation from the atmosphere, warming the ground, the air, and the water. I believe latent heat carries something like 78 W.m^2 averaged over the globe (higher over water, of course), while IR involves ~396 W/m^2 upward, and the atmosphere gives 324 W/m^2 downward, the sun 168 W/m^2. The IR exchanges and incoming sunlight are dominant. Increased evaporation (as someone correctly pointed out) is really dependent upon increased air temperature, as increasing temperature increases the possible partial pressure of water in the air.
28. h-j-m at 09:38 AM on 20 November, 2010
    KR, somehow your statements seemed odd. So I looked and found this Diagram. It gives the numbers in percent of total radiation and shows that your numbers can hardly be correct and I sincerely doubt that NOAA counts as a discredited source here. As to evaporation it seems you are seemingly mixing up possibility and reality. Warmer air can hold more water vapour therefore warmer air will lead to more evaporation. That seems to me the line of reasoning and it is a logical fallacy. Let me explain with the case at hand, evaporation. It should be obvious that the conditions governing the process need to be in place where the process takes place. Now I think it is no deep secret that the bulk of evaporation takes place over tropical ocean during daytime (when sunshine warms air and water). Unfortunately the bulk of warming occurs at far higher latitudes and during the night. Therefore it is quite unlikely that evaporation will significantly increase. The correct conclusion that can be drawn is that higher atmospheric temperatures may influence (diminish) the conditions that govern condensation (and precipitation in consequence) which by the way gives a perfect explanation for the ice loss of alpine glaciers in permafrost regions.
29. KR at 09:53 AM on 20 November, 2010
    h-j-m - See Trenberth 2009. My numbers are drawn from that. 80 W/m^2 evaporation, 17 W/m^2 thermals, 396 W/m^2 IR from the ground, with 161 W/m^2 solar and 333 W/m^2 back IR. (Sorry about the inexact numbers before, I was typing from memory) Warmer air will hold more water vapor - the same relative humidity at different temperatures leads to different absolute humidities. So warmer air over water at an unchanged temperature will end up with more absolute humidity, more H2O in the air column, more greenhouse effect. And warmer water can raise the relative humidity in the air above it, again raising the amount of H2O in the air column. So these effects interact. Increasing H2O therefore acts as positive feedback upon CO2 driven global warming.
30. h-j-m at 01:27 AM on 22 November, 2010
    KR, first you may have to explain why you estimate the diagram by Trenberth to be more reliable than that of NOAA. Besides, Trenberth states that he got the numbers for the IR radiation from the ground by calculations applying Bolzmann's law. I am pretty sure that if he tried living in quarters where the floor emits 396 W of IR peer square meter he will rather fast learn that this approach might be inadequate. Second, about my argument on evaporation. Unfortunately you completely failed to show any evidence that at least one part of my argument is wrong. Therefore I will apply Mr. Hitchens advice to your comment, though I am unaware that he is considered some sort of authority on science theory.
31. KR at 06:32 AM on 22 November, 2010
    h-j-m - The IR power emitted by the ground is a very straightforward application of Bolzmann's law, as well as per observation (with FTIR spectrometers and other instruments). And 396 W/m^2 is the correct number; that is what will be emitted from the ground and water at the current surface temperature. If you disagree with that, you're going to have to overturn a lot of physics! You don't feel it because at your body temperature you're emitting more than that. In an earlier version of the paper Trenberth estimated 390, then corrected it based on surface temperature variations - +/- swings around average temperatures, due to the T^4 term in thermal radiation, means that a varying temperature surface will emit a bit more than an evenly warm surface. The IR backradiation has also been directly measured, repeatedly and quantitatively, since the 1950's. (Stern, S.C., and F. Schwartzmann (1954) An Infrared Detector for Measurement of the Back Radiation from the Sky in J. Atmos. Sci., 11, 121-129. This documents early measurements of backradiation with a pyrgeometer). As to water vapor, you should read the page on Water vapor is the most powerful greenhouse gas. That states the scientific case regarding water vapor feedback more clearly than I can in a few lines.
32. h-j-m at 10:15 AM on 22 November, 2010
    KR, I checked about Bolzmann's law and failed to find any hint that it could be applied to a body surrounded by other matter. So I am rather confident that I don't have to "overturn a lot of physics!". About water vapour. The article you mention states: the level of water vapour in the atmosphere is a function of temperature. When I wrote about my argument against that notion (basically the same I gave in a previous post) concerning the wikipedia article on water vapour that part of the article got removed in response.
33. Alexandre at 10:24 AM on 22 November, 2010
    h-j-m Stefan-Boltzmann´s law applies to bodies. All of them. They all emit energy if their temperature is above 0ºK. What you said is like stating "Newton never said his laws applies to cars!".
34. DSL at 10:26 AM on 22 November, 2010
    h-j-m: "KR, I checked about Bolzmann's law and failed to find any hint that it could be applied to a body surrounded by other matter. So I am rather confident that I don't have to 'overturn a lot of physics!'." You also didn't find any hint that SB only describes emissivity in a total vacuum. Have fun here.
35. h-j-m at 02:53 AM on 23 November, 2010
    I think that any discussion about Bolzmann's law is rather off topic here as it is obviously not about heat transfers which I erroneously assumed. Anyway I am still waiting for a reply on my main point that I outlined in detail at my post #26.
36. KR at 04:01 AM on 23 November, 2010
    h-j-m - Your questions and proposed experiments (here and here) specifically attempt to disallow circulation and current effects. Currents (wind driven, salinity/thermal density driven) are primary mixers of the oceans, and redistribute surface temperatures elsewhere at varying rates. Studying a system without currents will not tell you much about the oceans. The oceans receive solar radiation and back IR, giving up energy via conduction/convection, evaporation, and IR (in increasing order of magnitude). The atmosphere is heated by conduction/convection, evaporation, solar and surface IR. At the top of the atmosphere all exchange is via EM, where the atmosphere is optically thin enough to actually radiate the IR to space. I'm failing to see what your issue with ocean heating is. Perhaps you could restate your concern?
37. TOP at 13:28 PM on 27 November, 2010
    If the ocean was feeding atmospheric warming, the oceans would be cooling. Boy, I don't follow this statement. If the oceans were feeding global warming they would have to be warmer than the atmosphere for heat transfer to occur. Heat flows from hotter to colder always whether it is conduction, convection or radiation. Since the oceans radiate very little it has to be conduction and convection. This is kind of like the beer illustration in reverse. Problems in assessment of the ultraviolet penetration into natural waters from space-based measurements interestingly seems to disregard or at least down play the role of the atmosphere (CO2 and air) in the absorption of UV in the oceans. The ozone hole, aerosols, clouds and the nature of the ocean with it's life seem to be bigger drivers of the absorption of UV. UV is of course a big player in warming the oceans.
38. Bibliovermis at 13:39 PM on 27 November, 2010
    Yes, there is a net flow of heat from hotter objects to cooler objects. That flow results in the cooler object becoming hotter and the hotter object becoming cooler. Hence, if the oceans were warming the atmosphere they would be cooling.
39. scaddenp at 14:04 PM on 27 November, 2010
    h-j-m. "The logical consequence of this claim is that rising atmospheric temperatures (due to anthropogenic global warming) causes rising ocean temperatures." But this is NOT what is happening. It is not warm air that is warming the sea - it is increased radiation (sun + backradiation) that is warming the sea. Ie radiative heating not conductive heating. And in that setting, it is warm ocean that is warming the air, not the other way round.
40. muoncounter at 07:38 AM on 16 February, 2011
    On another thread, friend BP linked to Compo 2009, claiming that ocean heating supposedly drives land heating. ... recent ocean warming ... has increased the humidity of the atmosphere, altered the atmospheric vertical motion and associated cloud fields, and perturbed the longwave and shortwave radiative fluxes at the continental surface. This proposed mechanism doesn't seem to make any sense, but it does argue for strong positive water vapor feedback.
41. Dana69 at 13:32 PM on 23 September, 2011
    Seems like the oceans aren't increasing in heat. What does this do to the AGW theory? Dr. Trenberth's 2009 lament that: "The fact is that we can't account for the lack of warming at the moment and it is a travesty that we can't.. Our observing system is inadequate." Note that Dr. Trenberth doesn't seem to countenance the possibility that the whole anthropogenic thesis - that the climate is driven by man-made industrial emissions - might be wrong. It is the absence of the real world to follow the models that is the alleged "travesty." "Subsurface temperature trends in the better-sampled parts of the World Ocean are reported. Where there are sufficient observations for this analysis, there is large spatial variability of 51-yr trends in the upper ocean, with some regions showing cooling in excess of 3°C," http://journals.ametsoc.org/doi/pdf/10.1175/JPO3005.1 A cooling ocean would falsify the validity of the AGW radiative forcing theory.
    Response:

    [DB] "Seems like the oceans aren't increasing in heat." and "A cooling ocean would falsify the validity of the AGW radiative forcing theory."

    Except for a lack of evidence to support those assertions.  Trenberth's most recent paper shows significant sequestering of OHC from the upper ocean into the deep ocean.  Coupled with Hansen's aerosol forcings hypothesis, the global energy budget appears to likely close.

    A refocus on science rather than unsubstantiated speculation would be of help to you.

42. Rob Painting at 16:37 PM on 23 September, 2011
    Dana69 - See SkS post: Ocean cooling corrected, again And note the warming oceans down to 1500 metres:
43. h-j-m at 04:27 AM on 5 March, 2012
    As KR pointed out in post 36 I would like to restate my concern to clarify what I see as a problem. Sorry to be a year late but more urgent personal affairs occupied my time meanwhile. First I am not supposing that the oceans are driving global warming but it hits me quite queer that a measured warming of the oceans is put up as proof for anthropogenic global warming over and over again. Unless my understanding is completely screwed up AGW (climate change) is based on the fact that various gases (mostly CO2) emitted by our industrial society are heating up the atmosphere due to the so called greenhouse effect. So far so well? Now I completely fail to understand what this has to do with rising oceanic temperature unless there is a physical process allowing for the atmosphere to heat up the ocean. Looking around I just found that on average ocean temperatures are higher compared to the atmosphere above which (according to the theory of thermodynamics) would not allow for such a process. But this in turn leads tho the conclusion that AGW and rising ocean temperature are unrelated and the so are the effects of the latter. But of cause if you leave out all the effects of rising ocean temperature you loose a lot of the most scaring predictions of AGW.
44. Tristan at 05:12 AM on 5 March, 2012
    various gases (mostly CO2) emitted by our industrial society are heating up the atmosphere due to the so called greenhouse effect. So far so well? Not quite. The GHGs reduce the amount of heat escaping into space. Over 90% of this heat takes up residence in the oceans. We focus on the extra heat kicking around in the atmosphere because it matters more to us (to the first order at any rate). It's also easier to measure surface temperatures and we've been measuring them for a long time.
45. Rob Painting at 05:25 AM on 5 March, 2012
    h-j-m@43 - the same greenhouse gases that trap heat in the atmosphere also trap heat in the ocean, via longwave forcing of the 'cool skin' layer of the ocean surface. See SkS post: How Increasing Carbon Dioxide Heats The Ocean.
46. michael sweet at 05:52 AM on 5 March, 2012
    hjm, You need to think it through before you talk. If you phrase your statements as a question you will not look like someone who is not serious about answers. The ocean loses heat to the atmosphere above it since it is warmer (as you point out). When the atmosphere warms, the ocean loses heat more slowly (according to the theory of thermodynamics as you referred to). When the ocean loses heat more slowly it warms. This is obvious to people who do not have an agenda to to discount the real problems caused by AGW. Summary: the ocean loses heat more slowly to a warmer atmosphere so the ocean increases in temperature.
47. TheCabbage at 02:51 AM on 20 December, 2015

    I think there's a basic point that a lot of people are missing here.  If the ocean was causing the warming, it would release excess CO2.  This is the case during natural warming cycles.  However, atmospheric CO2 is observed to be increasing while the ocean is becoming more acidic (i.e. still absorbing CO2).  This obviously points to a terrestrial CO2 source, but more importantly, it is evidence that the ocean is not the warming cause since oceanic CO2 is not decreasing.

48. TheCabbage at 02:55 AM on 20 December, 2015

    At least that is my understanding.  I think the cause is high atmospheric partial pressure of CO2.

49. jesscars at 15:10 PM on 13 June, 2019

    I believe this is a misrepresentation of the "skeptics'" argument being made.
    
    "Skeptics" believe that, before the industrial revolution, the correlation betweeon CO2 and temperature (as shown on records such as the Vostok Ice Coe records) was explained by:

    1) Natural factors causing the earth's temperature to change e.g. Milankovitch cycles, solar radiation cycles, and the circum-polar jet-streams.

    2) The ocean beng warmed or cooled due to these natural factors - which takes several hundred years (thus explaining the 800-year lag found on the Vostok Ice Core samples).

    3) The release or absorption of CO2 from the oceans, as the natural solubility or equilibrium level of CO2 in water changes with temperature. (The linear relationship of CO2 to water temperature (below about 23 degrees C.) also explains the linear historic relationship of temperature to CO2 (found at Vostok): which is about 1 degree C. to 10 ppm atm. CO2.)
    
    So yes, the historic source of CO2 was the oceans - and it was the temperature change, caused by natural factors, that caused this change.

    Response:

    [PS] Please quit spamming multiple threads.

50. scaddenp at 07:49 AM on 14 June, 2019

    This article is explicitly refuting William Gray assertion. Your points hardly reference that. In the past, CO2 most certainly came from ocean as it warms and it will again in a few 100 years (currently ocean is undersaturated for atmospheric CO2 levels and absorbing CO2). However, the current increase in CO2 is not from oceanic CO2 ( you cant have ocean as source when CO2 content in ocean is increasing), but from our emissions.

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