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Comments 1 to 25 out of 53:

1. GMB at 12:29 PM on 28 December, 2007
   "If the ocean was feeding atmospheric warming, the oceans would be cooling." Thats very weird thinking. The transmission goes like this: 1. Increased solar activity leads to oceanic warming. Leads to more water vapour, leads to atmospheric warming. 2. Increased solar activity leads to less invasion of cosmic rays, leads to less cloud cover, leads to greater oceanic warming, leads to water vapour, leads to atmospheric warming. 3. Increased solar activity, leads to greater momentum in oceanic currents, leads to greater imbedded energy in the oceans via the Stefan-Boltzmann's law. With regards to point 3. Were there some basic change to the "resistance to circulation". If some change in oceanic currents led to a better circulation or less resistance to circulation then you would expect the oceans to accrue more energy and that would eventually have the side effect of greater average global temperatures.
2. Quietman at 11:05 AM on 17 May, 2008
   John In keeping with this thread, you may be interested in a paper from Nature: AMO will stop warming until 2020. This seems to coincide with SSC24 as well. I added two links dealing with the AMO, PDO and ENSO cycles in Is Pacific Decadal Oscillation the Smoking Gun? as well as the ENSO related posts in It's volcanoes (or lack thereof) about the cause of El Nino/La Nina.
3. Quietman at 04:03 AM on 16 September, 2008
   Looking at the maps you will note that the warming occurs along ridge lines. This is NOT coincidental, nor is it caused by AGW but quite the opposite. Refer to comment 13 in the volcano thread linked above.
4. chris at 20:21 PM on 10 October, 2008
   Re #3 Quietman which maps are you referring to (in relation to your statement about warming on ridge lines)?
5. Quietman at 04:25 AM on 27 November, 2008
   chris Compare the charts of "hot spots" to a good map of the ocean floor such as Nat. Geo. maps. Also see post 115 in the volcano thread.
6. Quietman at 10:49 AM on 13 May, 2009
   [In 2005 James Hansen, Josh Willis, and Gavin Schmidt of NASA coauthored a significant article (in collaboration with twelve other scientists), on the “Earth’s Energy Imbalance: Confirmation and Implications” (Science, 3 June 2005, 1431-35). This paper affirmed the critical role of ocean heat as a robust metric for AGW. “Confirmation of the planetary energy imbalance,” they maintained, “can be obtained by measuring the heat content of the ocean, which must be the principal reservoir for excess energy” (1432). ... In 2007 Roger Pielke, Sr. suggested that ocean heat should be used not just to monitor the energy imbalance in the climate system, but as a “litmus test” for falsifying the IPCC’s AGW hypothesis (Pielke, “A Litmus Test…”, climatesci.org, April 4, 2007). Dr. Pielke is a Senior Research Scientist in CIRES (Cooperative Institute for Research in Environmental Sciences), at the University of Colorado in Boulder, and Professor Emeritus of the Department of Atmospheric Science, Colorado State University, Fort Collins. One of the world’s foremost atmospheric scientists, he has published nearly 350 papers in peer-reviewed journals, 50 chapters in books, and co-edited 9 books.] The Global Warming Hypothesis and Ocean Heat I think that this was an excellent point.
7. tallbloke at 00:54 AM on 15 October, 2009
   "What the science says... Oceans are warming across the globe." This is incorrect, although you might get away with saying they are warming on a six year average, for a little while anyway. Cazenave et al 2008 concludes that the steric sea level has been falling since 2006. The ARGO data shows that there has been a recent swift fall in ocean heat content globally. (Oct 2009 prelim data)
8. h-j-m at 01:14 AM on 16 August, 2010
   If the oceans are warming in response to increased atmospheric warming due to anthropogenic green house gases then undoubtedly there has to be a mechanism (physical or chemical) resulting in a net heat transfer from atmosphere to ocean. So far I completely failed to find such a mechanism mentioned. By contrast, most ocean-atmosphere interactions mentioned (el Nino, Gulf stream, fueling extreme weather events) constitute a net heat transfer the other way round. Further more, the quote provided by Quietman "the ocean, which must be the principal reservoir for excess energy”, clearly rules out any knowledge of a mechanism resulting in a net heat flux from atmosphere to ocean. But unless such a mechanism is found and sufficiently supported by evidence a warming of the oceans seems far more likely to cause global warming than anthropogenic increase in green house gases.
   Response: The mechanism of transferring heat from the atmosphere to the ocean is an increase in the amount of downward infrared radiation. Normally a certain amount of infrared radiation escapes out to space. But with greenhouse gases increasing in the atmosphere, this extra gas both absorbs and scatters the outgoing radiation and some of it returns to the Earth's surface.
   
   There are various independent lines of empirical evidence that this is happening. A series of papers analysing different satellite data find less infrared radiation escaping to space. Similarly, a number of different papers find more infrared radiation returning to the Earth's surface. So we have a mechanism for warming the oceans and evidence that this mechanism is indeed at play.
   
   For the record, I'm actually planning a post that specifically looks at the pattern of ocean warming and how it indicates human influence on climate - but just haven't had the time to write it yet.
   
9. Tom Dayton at 02:36 AM on 16 August, 2010
   h-j-m, you can conduct your own experiment to demonstrate that the atmosphere transfers energy to the ocean: Step 1: Chill beer. Step 2: Pour beer into glass. Step 3: Sip beer, noticimg its temperature. Step 4: Wait three minutes. Step 5: Go to Step 3.
10. h-j-m at 22:03 PM on 16 August, 2010
    Seemingly some more explanation is necessary. It is obvious that atmospheric infrared radiation hits the oceans. But if and to which extend that results in a warming of the ocean is a completely different question. For example it is quite obvious that one of the results will be an increase of evaporation which can result in a net cooling. Then there is the question of penetration i. e. how far can infrared radiation penetrate the water to warm it. As some reports claim a warming of the oceans down to 700 meters this quite clearly can hardly be explained by exposure of the surface to increased infrared radiation. Anyway I see the main weakness of this theory in the missing attempt to rule out alternative causes. Tom Dayton: Your experiment needs some more elaboration. 1. How to make sure that the only source of heat comes from the atmosphere above as I doubt that a glass provides enough insulation for that. 2. How to sip some of that beer (assuming that to be an adequate measurement method) without inducing currents within the liquid which will scramble up and disturb the current heat distribution.
11. Karamanski at 11:46 AM on 8 October, 2010
    A paper by Mojib Latif predicted that changes in ocean circulation in the Atlantic could cause the rise in global surface temperatures to stall for a decade or two. How exactly would changes in ocean circulation cause global warming to temporarily slow for a decade? Is this related to the Atlantic Multi Decadal Oscillion? Would this have any effect on ocean heat content? I've been curious about this for a long time. Please explain this.
12. Doug Bostrom at 15:50 PM on 8 October, 2010
    Karamanski, I believe you're thinking of Keenlyside et al 2008 (full text, pdf) which includes Mojib Latif as a coauthor. The abstract is probably better to read directly rather than letting someone else paraphrase it. The key lies in the words "surface temperature" and regional variability, how much heat is available where we can measure it in various regions of the surface temperature network and different regions of ocean surface. Keenlyside predicted a regional cooling in the North Atlantic area caused by circulation changes in the North Atlantic ocean, sufficiently strong as to cause a change in the overall surface temperature trend, even as other areas of the globe continued to warm. Behind all this is no change in the total amount of energy being retained on the planet, rather a change in distribution. Popular press treatments of this paper conveyed the impression that warming was going to stall or even that the Earth was going to cool, which is wrong in terms of energy being retained on Earth during the period covered by Keenlyside's prediction. Richard Wood explains this in a commentary at Nature accompanying Keenlyside et al: [Keenlyside's] starting point is the ocean. On a time scale of decades, this is where most of the ‘memory’ of the climate system for previous states resides. Anomalously warm or cool patches of ocean can be quite persistent, sometimes exchanging heat with the atmosphere only over several years. In addition, large ocean current systems can move phenomenal amounts of heat around the world, and are believed to vary from decade to decade. Wood goes on, regarding the extent of the predicted cooling: The authors use their model to predict that the MOC will weaken over the next decade, with a resultant cooling effect on climate around the North Atlantic. Such a cooling could temporarily offset the longer-term warming trend from increasing levels of greenhouse gases in the atmosphere. That emphasizes once again the need to consider climate variability and climate change together when making predictions over timescales of decades. On a parenthetical note, it's fun when scientists bet money on validation. Some climate researchers found Keenlyside's analysis and forecast sufficiently debatable as to offer a bet on the outcome.
13. Karamanski at 01:08 AM on 10 October, 2010
    Keenlyside et al 2008 states that a weakening of the Atlantic meriodional overturning circulation will cause North American and European temperatures to stall or cool slightly. How exactly would changes in Atlantic SSTs cause temperatures on the adjacent continents to cool? And the paper did not clarify which parts of the globe would continue to warm while North America and Europe cool slightly. Is it similer to the way ENSO affects global surface temperatures?
14. Doug Bostrom at 04:54 AM on 10 October, 2010
    Karamanski, surface temperatures of the North Atlantic have a powerful influence on climate adjacent to the North Atlantic. There's a useful article here from Woods Hole providing a general explanation. It's a bit old, but it provides lots of search terms for following things forward.
15. Karamanski at 07:32 AM on 10 October, 2010
    Are variations in the Atlantic meriodional overturning circulation driven by the imput of fresh water from the Arctic? Keenlyside et al 2008 did not state what the drivers for a weakening of the Atlantic meriodional overturning were, the paper just used historical analogs of certain regions of the North Atlantic and extrapolated current conditions using climate models. Comparing Keenlyside et al 2008 and the article you provided, the mechanism described in Keenlyside's paper seem to be cyclical on multidecal timescales, while the ocean conveyer discussed in the article you provided is changed by an external factor rather than internal variability. Are the Atlantic meridional overturning circulation and the Great Ocean Conveyor interelated?
16. Doug Bostrom at 07:57 AM on 10 October, 2010
    At some point you're going to find it irresistible to use Google Scholar, Karamanski. Going directly to the well is much more efficient than relying on generalists such as myself to function as proxies hauling teaspoons of information. Plus, why trust me when you can eliminate a layer of fallible human nature and go straight to researchers themselves?
17. h-j-m at 05:25 AM on 17 November, 2010
    Claims that the warming of the planet is due to heat being released from the oceans into the atmosphere are not supported by any empirical evidence or peer-reviewed science. Thus ends the article. But if I am not mistaken the temperature of the water is one of the dominant factors determining the rate of evaporation (i. e. the warmer the water the higher the rate of evaporation). But more evaporation equates to more water vapour in the atmosphere (aka latent heat) which will result in warming the atmosphere. Else a lot of physics text books need rewriting. In a previous post I complained about mentioning alternative explanations for rising ocean temperatures. I will give just three with the humble request to be shown how or where these are debunked. 1. Marine as any other life needs energy to build its biomass. By now we are next to successful clearing our oceans of it. In consequence that energy is not used for this purpose and heats the water instead. 2. There may be spots where the earth crust has grown thinner over time and therefore more of the earth's interior heat gets transferred to upper layers. As the earth's crust is thinnest below oceans this may heat the water above. 3. Not only are we clearing out next to all marine life from the oceans we are using them as garbage bins as well. I recall reports stating that all over the oceans probes were taken that revealed a higher content of plastics than phytoplankton. I think it is rather likely that these areas when hit by visible light will absorb more of it and in return emit more infrared radiation aka heat.
18. KR at 05:39 AM on 17 November, 2010
    h-j-m - Do you perhaps have any evidence that one of your alternative theories is true? You've put forward three different hypotheses, without numbers or supporting evidence - as opposed to the article this thread is based upon. And to quote Christopher Hitchens, assertions without evidence can be dismissed without evidence. As to warmer water leading to evaporation and more warming, well, that's absolutely true, one of the basic positive feedbacks to temperature change. That's well understood basic physics, and doesn't lead to a runaway situation, if that's what you're implying.
19. Phil at 07:20 AM on 17 November, 2010
    h-j-m #17 But more evaporation equates to more water vapour in the atmosphere (aka latent heat) which will result in warming the atmosphere. This is incorrect, I believe. The amount of water vapour that the atmosphere can hold is determined only by the temperature of the atmosphere. Factors that increase only the rate of evaporation will simply increase the rate of condensation out as well. In the atmosphere that means clouds form faster and then more precipitation. 1. Marine as any other life needs energy to build its biomass. By now we are next to successful clearing our oceans of it. In consequence that energy is not used for this purpose and heats the water instead. I would think the main route for marine life to obtain energy is photosynthesis and respiration. Indeed, given biochemistry, I would expect respiration inside marine animals to keep them at a higher temperature than the water (blubber in marine mammals would seem to corroborate this). Therefore I think denuding the oceans would most likely have a nett cooling effect. 2. There may be spots where the earth crust has grown thinner over time and therefore more of the earth's interior heat gets transferred to upper layers. As the earth's crust is thinnest below oceans this may heat the water above. This is beyond my realm of expertise, but I would note that what is actually required is a nett thinning of the crust for the oceans to get warmer. "some spots" is not, of course, sufficient. 3. Not only are we clearing out next to all marine life from the oceans we are using them as garbage bins as well. I recall reports stating that all over the oceans probes were taken that revealed a higher content of plastics than phytoplankton. I think it is rather likely that these areas when hit by visible light will absorb more of it and in return emit more infrared radiation aka heat. Phytoplankton photosynthesize (by definition) which is the absorption of visible light, I would imagine they are better at it than plastic, unless perhaps most of the plastic is black ...
20. muoncounter at 08:31 AM on 17 November, 2010
    #17: "As the earth's crust is thinnest below oceans this may heat the water above." Not by much. Here's what Douglass and Knox 2009 have to say about tectonic heating: The geothermal contribution is constant [certainly over human time scales], but cannot be ignored because it contributes directly. The flux into the ocean and trenches averages 101 ± 2.2 mW/m² and that into the land and shelves averages 65 ± 1.6 mW/m² (globally averaged, 87 ± 2.0 mW/m²) --emphasis added Compare to solar heat flux, same source: The mean solar flux S0 at the earth’s orbit is assumed to be 340 W/m²±1 W/m² A sizable difference in favor of solar heat.
21. h-j-m at 06:13 AM on 18 November, 2010
    KR, no I don't have any evidence, but neither did I forward any hypothesis. But my understanding about science tells me that in order to establish any hypothesis (e. g. anthropogenic global warming caused by increasing emissions of - mainly - CO2) you need to look at all possible causes and either rule them out or show their insignificance. If I were a scientist that is I would do prior to finding evidence to back my intended hypothesis. The history of the AGW hypothesis seems to have developed the other way round. About water vapour: I just wanted to point out that the cited quote can't be correct as there is an established method of heat transfer from the ocean to the atmosphere while I still could not find any hint of significant heat transfer the other way round. By the way, so far the only explanation I encountered about AGW causing oceanic temperature rise was that the oceans are (due to their thermal capacity) the only available heat sink. That clearly qualifies as an assertion without evidence. muoncounter, Thanks, this is the kind of reply I would have generally expected (but seemingly I'm asking too much). Unfortunately the data that is referred to are from a paper published in 1993 and is therefore rather useless given the fact that reports about rising ocean temperatures state them to be most significant in the last decade. Besides, due to the theme of this site you should have selected the alleged additional heat flux from anthropogenic global warming as comparison.
22. KR at 06:23 AM on 18 November, 2010
    h-j-m - In that case, prior to accepting your hypotheses (and yes, you did propose three of them) and dismissing the mass of evidence for greenhouse enhancement via increased anthropogenic CO2, you need to display both some evidence for your hypotheses. And point out why that evidence is better than the evidence for CO2. You don't do science by hunting for and debunking all possible and dreamed of hypotheses (as that is an infinite set), which is what you seem to be asking for - you do it by following the evidence, learning what common events and generalizations can be made, and examining the evidence for and against them.
23. CBDunkerson at 06:23 AM on 18 November, 2010
    h-j-m wrote: "But my understanding about science tells me that in order to establish any hypothesis (e. g. anthropogenic global warming caused by increasing emissions of - mainly - CO2) you need to look at all possible causes and either rule them out or show their insignificance. The history of the AGW hypothesis seems to have developed the other way round." You must be reading a different history than the one I've seen. When Arrhenius first proposed enhanced greenhouse warming from human CO2 emissions in 1896 a whole host of objections (CO2 absorption is saturated, water vapor absorption overlaps, oceans can absorb all the extra CO2, human emissions are too low, et cetera) were raised and the idea was dismissed. It is only as each of those, and many other, objections has been disproved over the subsequent decades that it has become clear that Arrhenius was correct.
24. muoncounter at 07:04 AM on 18 November, 2010
    #21: "the data that is referred to are from a paper published in 1993" The paper I cited was published in 2009. Do you think those authors knowingly used the 1993 data (which has been cited by 167 subsequent papers through 2010) without some consideration of whether or not they were still appropriate? More to the point, do you think the earth's geothermal heat flow into the oceans varies by a 3 orders of magnitude (we're talking watts vs. milliwatts) over the course of 17 years? Everybody would have noticed that!
25. muoncounter at 07:20 AM on 18 November, 2010
    Just noticed your other notion in #21: "should have selected the alleged additional heat flux from anthropogenic global warming as comparison." Yes, the 'alleged' GHG forcing, as shown here still trumps this 0.087 W/m² from geothermal 30 or times over. What was your point?

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