Global Warming and Ocean Heat

William DiPuccio has a really very readable and clear post on using ocean heat content to falsify current global warming model projections. He argues pretty persuasively that surface air temperature measurements are a really, really poor way to search for evidence of a man-made climate forcing from CO2.

Since the level of CO2 and other well-mixed GHG is on the rise, the overall accumulation of heat in the climate system, measured by ocean heat, should be fairly steady and uninterrupted (monotonic) according to IPCC models, provided there are no major volcanic eruptions.  According to the hypothesis, major feedbacks in the climate system are positive (i.e., amplifying), so there is no mechanism in this hypothesis that would cause a suspension or reversal of overall heat accumulation.  Indeed, any suspension or reversal would suggest that the heating caused by GHG can be overwhelmed by other human or natural processes in the climate system….

[The] use of surface air temperature as a metric has weak scientific support, except, perhaps, on a multi-decadal or century time-scale.  Surface temperature may not register the accumulation of heat in the climate system from year to year.  Heat sinks with high specific heat (like water and ice) can absorb (and radiate) vast amounts of heat.  Consequently the oceans and the cryosphere can significantly offset atmospheric temperature by heat transfer creating long time lags in surface temperature response time.  Moreover, heat is continually being transported in the atmosphere between the poles and the equator.  This reshuffling can create fluctuations in average global temperature caused, in part, by changes in cloud cover and water vapor, both of which can alter the earth’s radiative balance.

One statement in particular really opened my eyes, and made  me almost embarassed to have focused time on surface temperatures at all:

For any given area on the ocean’s surface, the upper 2.6m of water has the same heat capacity as the entire atmosphere above it

Wow!  So oceans have orders of magnitude more heat capacity than the atmosphere.

The whole article is a good read, but his conclusion is that estimates of ocean heat content changes appear to be way off what they should be given IPCC models:

dipuccio-2

My only concern with the analysis is that I fear the authors may be underestimating the effect of phase change (e.g. melting or evaporation).  Phase change can release or absorb enormous amounts of heat.  As a simple example, observe how long a pound of liquid water at 32.1F takes to reach room temperature.  Then observe how long a pound of ice at 31.9F takes to reach room temperature.  The latter process takes an order of magnitude more time, because it absorbs an order of magnitude more heat.

The article attached was necessarily a summary, but I am not totally convinced he has accounted for phase change sufficiently.  Both an increase in melting ice as well as an increase in evaporation would tend to cause measured accumulated heat in the oceans to be lower than expected.   He uses an estimate by James Hansen that the number is really small for ice melting (he does not discuss evaporation).  However, if folks continue to use Hansen’s estimate of this term to falsify Hansen’s forecast, expect Hansen to suddenly “discover” that he had grossly underestimated the ice melting term.

  • http://www.miltonconservative.blogspot.com/ Bill MacLean

    The oceans and atmosphere tend to be in equilibrium. The heat of evaporation is identical to the heat of condensation. As long as the evaporated water recondenses, the heat will remain constant in the system. Temperature differences in the atmosphere generate pressure/density difference causing mixing. One can see large temperature differences in small areas due to adiabatic expansion – thunder storms. Generally the atmosphere is more prone to large temperature excusions than the oceans, greatly increasing the uncertainty of local temperature measurements.

  • hunter

    “Wow! So oceans have orders of magnitude more heat capacity than the atmosphere.”

    Yep. Perhaps now the penny has dropped, you’ll stop posting your perennial bullshit arguments that ignore any lags in the climate system.

    Your graph is largely fiction. No model predicts a monotonous upward rise. Unsurprisingly, you don’t plot the error bars on the observations.

  • hunter (the real one)

    The missing of heat content, like Jennifer’s missing ability to understand the concept of heat vs. temperature, is jsut one of the reasons to know AGW is bogus.
    Notice taht not *one* AGW prediction actually holds up in the real world, except for the heroic and trollish efforts of our dear friends like Jennifer, Hansen, Gore, etc.
    They cannot deal with the issues. They can only attack those who point out the issues.
    The issue is that the GCM models are not holding up at all.
    The issue is that the predicted apocalypse is not happening, and is not likely to at all.

  • hunter

    On the idea that the heat went from the oceans to melting ice: They can try, but they will fail, to save AGW with that rationalization.
    The ice is, on a worldwide basis, within one std. deviation or less.

  • markm

    How is the heat content of the ocean measured? I am under the impression that nearly all of the measurements are of near-surface temperatures (compared with the usual depths of thousand of feet), but the near-surface temperature of any particular spot of ocean has far more to do with the circulation patterns that exchange water and heat with the deep ocean than with the heat gain or loss from the surface.

    But if you can get valid measurements of the overall ocean heat, you don’t need anything else to measure long term global temperature trends. I could build a circuit that is so chaotic that it’s impossible to predict future voltages – but if I tie a room-sized capacitor to it through a resistor, that capacitor will keep an average of the voltage over a long period, and if it’s going down, the long term trend is the voltage is going down.

    Anything happening in the atmosphere is just a tiny ripple on top of the heat gained or lost in the deep oceans – and if those scientists are correct, the globe has been COOLING for a long time. How long? I don’t know how to calculate the response time for oceanic heat sinks (that is, I can estimate the equivalent of “C” in “RC”, but can’t even guess at “R”). If the average ocean temperature is going down, the globe might not be cooling as fast as previously, but the global average temperature must still be lower than the average of the last few centuries or millenia, however long it would take for the ocean to reach a new temperature level if the temperature ever stayed level.

  • Steve

    My mother once told me that a person who requires foul (or digusting) language to make a point has lost the respect of the intelectuals around them.

  • Bob Zorunkle

    hunter: “Yep. Perhaps now the penny has dropped, you’ll stop posting your perennial bullshit arguments that ignore any lags in the climate system.”

    I would think that lags in the climate system would be problematic for the AGW proponents. Since industrialization is only a recent phenomenon, if the lag is determined to be anyting over 50 – 100 years, it would pretty well destroy the AGW argument – at least with regard to the warming in the 1980 – 1998 period. However, a lag would certainly verify the proposition that temperature is the driver and CO2 is the follower, as shown in the approximately 6-700 year lags in the long range temp history.

  • Steve

    OK MORON HUNTER (the extremely fake one) If you would bother to read any of the vastly available refuting data on so called recent global warming you would know that the mean you and all the othe doomsayers use is not valid as it doesn’t reflect the LONG TERM temperatures (for those of you with limited vision) this means the last 100,00o years. Read “Limitations on AnthropogenicGlobal Warming” by Leonard Weinstein, ScD dated March 1,2009

  • Steve

    OOPS I made a mistake and posted this comment on the wrong arguement site. I meant to post on the site regarding the 10 acres of permafrost loss. I am very sorry if I offended the real Hunter or any one else.

  • Jim

    Climate Skeptic – Is the study cited by the link later than the evidence in the discussion in the link below? The AWG alarmists here are presenting evidence the Argo floats were mis-calibrated and the cooling was instrumental error. Climate Skeptic, anyone, which is it?

    http://www.skepticalscience.com/Mystery-of-the-vanishing-ocean-heat.html

  • hunter

    Jim,
    Notice how when AGW predictions are proved wrong, it is never because their theory needs correcting, but rather because the instruments were wrong, or the evil companies were misleading people?
    No other science is ever immune to mistakes like AGW.
    Then again, that is one of the important evidences taht AGW is not science in the first place.

  • Jim

    Here’s the thing. The link provided by Climate skeptic cites the paper below as being from 2009. This link cites a paper from 2006 with the same title. Soooo, what’s up with that?? Which is right.

    Here’s the link and a quote from it below:

    http://www.skepticalscience.com/Mystery-of-the-vanishing-ocean-heat.html

    “First, to clear up one common misconception. One paper oft quoted is Recent Cooling of the Upper Ocean (Lyman 2006). This found a rapid drop in ocean heat from 2003, as measured by the Argo network deployed in 2000. Argo is a global array of 3,000 free-drifting floats that measures the temperature and salinity of the upper 2000 metres of the ocean.”

  • Jim

    The Argo data problem was written up in 2007, so if there is a “Recent Cooling of the Upper Ocean” paper from 2009, it would be significant.

    Here is a link to the correction paper.

  • Jim

    I apologize for the multiple posts. I found another reference to the 2009 work on the Argo floats. Looks like we have bone here…

    http://jennifermarohasy.com/blog/2009/03/the-ocean-really-is-cooling/

  • Jim

    Here is another recent paper attempting to resurrect a warming trend from ocean temperature data. The problem here is that they include a multitude of corrections to various temperature measurement methods thereby finding a warming trend. I see no reason not to rely on the Argo data which agrees with the modern and global satellite data.

    ftp://ftp.nodc.noaa.gov/pub/data.nodc/woa/PUBLICATIONS/grlheat08.pdf

  • Dave

    Hunter wrote that the graph was mostly fiction. If true, where’s the non-fiction stuff?. You know, the unfalsified, unbiased data that use to be presented back when we all worked together to better our understanding of Atmospheric Science/Climate? We’re living in great time with all that is going on. Do ya all have to keep clubbing each other over the head? Oh well, there’s still astronomy.

    -Dave

  • JP

    MarkM,

    For what it’s worth, ocean heat content is measured in Joules, and is derived from Agro bouys that take both near surface and deep ocean measurements. Lyman from the JPL has published a number of papers that calculated heat content for the last 15-18 years.

    As far as the “change of states” (or phase changes) in water (liquid-vapor, vapor-liquid,liquid-solid, and solid-vapor/liquid), I was always taught that the net energy is conserved, and balance is reached through the water cycle. If we even take oceanic heat content into account, the oceans are constantly in flux, transporting warmer waters poleward, cool waters equatorward, or radiating the surface heat back into space. A net increase in energy (measured in Joules) would occur if more “energy” was getting to the earth, and being added to the budget. I do agree that surface or near surface temperatures is a very poor proxy to measure this energy balance. That’s why I’ve always held little stock in any of the temp trends. The oceans can hold more heat, as the land radiates most of its heat back into space. Ergo, we should be spending more time and effort looking at our oceans.

    So, much for my rant.

  • http://www.skepticalscience.com/ John Cook

    The article http://www.skepticalscience.com/Mystery-of-the-vanishing-ocean-heat.html is a little outdated. An updated post that directly addresses William DiPuccio’s article is http://www.skepticalscience.com/Does-ocean-cooling-disprove-global-warming.html

    It makes two points. Firstly, over the past 40 years of warming in the upper ocean waters, there are many short periods where the ocean cools for several years. This is due to internal variability, the most dominant cycle being the El Nino Southern Oscillation – where heat is exchanged between the upper ocean, the atmosphere and deeper waters.

    Secondly, there is some uncertainty in the Argo data due to biases introduced by pressure sensor issues. Some reconstructions of Argo show a slight cooling, some show a slight warming. How to know which are more accurate? One paper calculates ocean heat through 3 different independent methods and finds an overall warming trend over the past 5 years.

    Nevertheless, the warming is less than the long term 40 year average. This brings us back to point 1 – short term variations in ocean heat. We’re currently in La Nina phase which imposes a cooling influence on global ocean heat.

  • Nikolaj

    But, there is no “increase in melting”. Global sea ice is not changing, Antarctica and Greenland ice sheets are not melting, but rather gaining ice. There is no “melting” to be accounted for in. Melted ice cannot artificially lower ocean heat content simply because it doesn’t exist!