After reading Bob Tisdale at WUWT I made my first visit yesterday to HotWhopper to examine a post on ocean heat content. (Though this doesn’t concern the report from our Commissioner for the Environment, it addresses the fundamental science, so please bear with me.) Miriam O’Brien (a.k.a. Sou) writes:
The oceans absorb more than 90% of the extra energy that’s being built up in the system.
This caught my attention as lying at the centre of her argument. But we need to ask where the heat comes from and how it gets into the ocean.
As we know, the oceans warm from the direct heat of the sun. The hypothesis (and it’s still only an hypothesis, it’s not yet a theory) that the oceans also warm from the effects of man-made global warming depends on heat energy reaching them by radiation from atmospheric gases (the so-called greenhouse gases).
Trouble is, physics is against it.
The only explanation I’ve seen of a possible mechanism for atmospheric ocean heating was at Skeptical Science in 2011, based on a highly speculative guest post in 2006 by Dr Peter Minnett at Real Climate, and those are indeed cited in Miss O’Brien’s reply to my inquiry, though the explanation is no more convincing now than it was back then.
If the scientists supporting AGW alarm were sincere in wanting to know their subject, some at least would have tried harder to perform further experiments in this area, because it’s so very vital to the danger they predict. Since human activities can only heat the air, if the air cannot heat the water, much of the threat of dangerous AGW vanishes because the water is not expanding and rising through our influence.
But since they have not investigated, they do not wish to know.
Courtesy of our industrious friend Richard Cumming, we described the skin layer phenomenon and its deficiencies last year. Clearly, repetition is needed.
In the mechanism as described at Real Climate, an immeasurably small temperature gradient across the sub-millimetre skin layer of the ocean (except across the vast regions of turbulence, which destroys the skin layer) holds at bay a portion of the gigantic quantity of solar heat energy wanting to rise again from the water and escape to space, warming the air as it goes.
It was an experiment on board the New Zealand research vessel Tangaroa in 2004 that measured the temperature gradient across the skin layer. It seems to have been 0.002°K (W/m2)-1—astoundingly small. Since they couldn’t vary the amount of carbon dioxide above the ship, they measured the amount of infrared energy emitted by changing cloud cover.
Experiment did not prove CO2 warms the ocean
The serious limitations of this experiment are given away by Dr Minnett’s honest admission at the end of the post (by which frankness nevertheless he reveals his genuine scientific heart):
Of course the range of net infrared forcing caused by changing cloud conditions (~100W/m2) is much greater than that caused by increasing levels of greenhouse gases (e.g. doubling pre-industrial CO2 levels will increase the net forcing by ~4W/m2), but the objective of this exercise was to demonstrate a relationship.
Unfortunately that doesn’t prevent him from using the following weasel words in an utterly misleading conclusion that the experiment has proved what all the warmists wish to believe, which is that human activity is heating the ocean (you’ll notice that he doesn’t actually say that):
To conclude, it is perfectly physically consistent to expect that increasing greenhouse gas driven warming will heat the oceans – as indeed is being observed.
(Note that what was being observed was warming, not the method of warming.) No attempt was made to quantify the effect in terms of the real-world ocean. We want to know how much heat energy is prevented from leaving the water, how much the water thus warms and, crucially, how much atmospheric cooling is caused by the energy being withheld in this way.
As the atmosphere warms more and more, the amount of heat energy blocked in this way (if significant) constitutes a hitherto unsuspected negative feedback. This, of course, calls for further research, since it further reduces the impact of ‘dangerous’ AGW.
It strikes me today on rereading that this is not so much scientific revelation as it is the attempted birth of a legend.
Considering the minuscule addition by CO2 radiation to the temperature of the skin layer and the amount of thermal energy the skin layer is attempting to block, we’re being asked to believe that an ant might significantly impede a charging lion.
Yet nobody at HotWhopper seems to mind this.
I’ve posted this response here because it makes a few good points, and Miss O’Brien has declined to publish it at HotWhopper, which confirms her ill intentions towards a proper discussion. By implication, she declares that I’m telling whoppers (lies) but refuses to assist by describing them.
My reply at HotWhopper
Sou, thank you for your courteous response.
You confirm what I could not have known without asking (never mind the allegation of ‘faux curiosity’), as I neither know everything, nor do I read minds, that you rely upon the Skeptical Science post and the Real Climate article by Dr Minnett to support your assertion that greenhouse gases significantly warm the ocean.
Unfortunately, the experiment described by Dr Minnett does not support you, substantially because they didn’t measure the warming influence of CO2, they measured the varying amount of infrared radiation from clouds, which intercepted the infrared as it tried to leave the surface.
Contrary to what you say, there is no evidence that the minuscule radiation from CO2 molecules might have a significant effect on the temperature of the ocean. The experiment was designed, as Dr Minnett explains, not to quantify the effect, but only to demonstrate it. It’s surprising, in light of its apparent success in doing so, that no further experiments appear to have been conducted in this area, including nothing to establish its magnitude.
Perhaps that lack of interest springs from the fact that the experiment discovered yet another hitherto unsuspected negative feedback to increasing radiative forcing.
Because the skin layer, as it warms, prevents a little thermal energy from escaping the oceans. That heat no longer warms the atmosphere, which rather defines a cooling influence.
Still, without knowing the magnitude of the warming effect on the skin layer and the consequent reduction in heat flux from the water, we can’t be sure how important this is, can we? There is of course no reason to believe it will destroy us by 2100.