Saturday, February 22, 2014

The Claim that the "Missing Heat" is Going into the Oceans

One claim I have repeatedly seen in online arguments about global warming is that it has not really paused because the "missing heat" has gone into the ocean. Before asking whether that claim is true, it is worth first asking how anyone could know it is true. A simple calculation suggests that the answer is one couldn't. As follows ... .

Part of the claim which I assume is true is that from 90% to 95% of global heat goes into the ocean. That implies that the heat capacity of the ocean is 10 to 20 times that of the rest of the system. If so, and if the pause in surface and atmosphere temperatures was due to heat for some reason going into the ocean instead, that should have warmed the ocean by 1/10 to 1/20th of the amount by which the rest of the system didn't warm.

The global temperature trend in the IPCC projections is about .03°C/year. If surface and atmospheric temperature has been flat for 17 years, that would put it about .5° below trend. If the explanation is the heat going into the ocean, the average temperature of the ocean should have risen above its trend by between .025° and .05°.

Would anyone like to claim that we have data on average  ocean temperature accurate enough to show a change that small? If not, then the claim is at this point not an observed fact, which is how it is routinely reported, but a conjecture, a way of explaining away the failure of past models to correctly predict current data.

The next question is what has actually happened to heat content. The data are shown at

http://www.nodc.noaa.gov/OC5/3M_HEAT_CONTENT/.

The page insists on showing you a series of different graphs, so I am pasting in a screenshot of the first one. The second shows heat content down to 2000 meters; you are welcome to look at that and see if you agree with me that it shows the same pattern, if a little less clearly.

Examining the graph, in particular the black line showing the yearly average, it looks as though the rate of increase from about 2003 on is slower, not faster, than over the previous decade. The change is not as striking as the corresponding change in the graphs of surface or atmospheric temperature and seems to start a little later, but it is just the opposite of what we would expect if the slower warming elsewhere was being balanced by faster warming of the ocean. And, since the ocean is being heated from above, one would expect the pattern of ocean temperature to lag the pattern of atmospheric temperature.

Anyone interested in disputing either half of this post and defending the claim that there has not really been a slowdown in global warming because the missing heat went into the ocean? I am not looking for links to articles claiming that it's true—too much of the online argument on climate consists of dueling appeals to authority. I'm looking for actual arguments.

11 Comments:

At 12:33 PM, February 22, 2014, Blogger Jesse Huebsch said...

I think you are confusing heat flow (power or energy over time) with heat capacity (energy per unit temperature change). The heat capacity of the ocean is on the order of 1000x that of the atmosphere - http://wattsupwiththat.com/2011/04/06/energy-content-the-heat-is-on-atmosphere-vs-ocean/
There is no requirement that the temperature change is the same in each, especially because the mixing of the layers of the ocean has lags measured in decades or longer.

 
At 1:54 PM, February 22, 2014, Blogger Rick Caird said...

I have been quite skeptical of the idea that heat is being stored in the deep ocean because no one seems to be able to explain how it gets there or how it gets there without passing through and affecting other parts of the ocean or land masses.

The idea that heat is being stored in the deep ocean is just wishful thinking for an explanation of why we are not seeing the predicted heating.

 
At 3:18 PM, February 22, 2014, Blogger David Friedman said...

Jesse:

If the reason the atmosphere didn't warm was that the extra heat went into the ocean, then the ocean's average temperature would have to rise by the amount the atmosphere didn't times the ratio of atmospheric heat capacity to oceanic capacity.

My implicit assumption was that claims such as "95% of the heat is in the ocean" described equilibrium, at which temperature is equalized and the amount of heat in each reservoir is proportional to its heat capacity. If you are correct about heat capacities, then my argument is even stronger than I thought.

 
At 3:01 AM, February 23, 2014, Blogger Tim Lambert said...

I don't think you have understood the argument you are disputing. The graph you show of ocean content in the upper ocean doesn't show any pause, so you cannot say that global warming has paused.

We know that more energy is coming in than going out (see here for a summary of the evidence). Energy is conserved, so the energy must be going somewhere. The energy increase in the oceans is consistent with the energy going there and I can't think of any other plausible place it could go, can you?

There is also direct evidence of an increased rate of heat going into the oceans if you look at the spacial variation of the changes in heat content. See here.

 
At 4:15 AM, February 23, 2014, Blogger A Life Long Scholar said...

I haven't made a study of the relative magnitudes of the sources of various temperature fluctuations in the ocean, but I would think that the magmatisim at the mid-ocean spreading centers and hot-spots under the ocean crust, combined with the black-smokers on the ocean floor must be contributing a certain amount of heat to the ocean from beneath.

 
At 6:35 AM, February 23, 2014, Blogger Fred Mangels said...

RC wrote, "The idea that heat is being stored in the deep ocean is just wishful thinking for an explanation of why we are not seeing the predicted heating.".

I'd suggest it's simply scurrying around looking for excuses when their models don't work out as they believe they should. Rather than look back to see if their original assumption (global warming) is wrong, they're trying to make the evidence fit their foregone conclusion.

 
At 7:51 AM, February 23, 2014, Blogger Fred Mangels said...

I'm not normally a fan of Charles Krauthammer, but I thought he was spot on in his commentary in the Washington post criticizing the idea that the science of global warming was "settled". Very nicely written.

Predictably, the comments to his piece- at least the first few I read- were along the lines of the old us vs. them:
http://www.washingtonpost.com/opinions/charles-krauthammer-the-myth-of-settled-science/2014/02/20/c1f8d994-9a75-11e3-b931-0204122c514b_story.html

 
At 7:52 AM, February 23, 2014, Blogger Fred Mangels said...

Here's an abbreviated url if the above one can't be made to work:
http://tinyurl.com/mp93vrn

 
At 9:37 AM, February 23, 2014, Blogger Jesse Huebsch said...

David, that is correct that the the oceans average temperature would have to rise by the amount that the atmosphere did not times the ratio of Catmosphere / Cocean. If the ratio is 1/1000x then for the missing 0.5C in the atmosphere, the ocean would have had to rise an extra 0.0005C beyond trend. I think that might be hard to detect.
The mass of the atmosphere is equivalent to a layer of water 30ft deep (14.7 pounds per square inch is a standard atmosphere, 14.7 pounds of water in a coulumn and inch square is about 30 feet). Water has about 4 times the heat capacity of air per pound, so in terms of heat capacity the atmosphere is like a layer of water 8 feet deep. You can see why the ocean is so dominant on temperature over the atmosphere.

 
At 11:29 AM, February 23, 2014, Blogger Jesse Huebsch said...

I should also add that if the statement that 95% of the heat goes into the ocean is correct, in the period of time where we would expect 0.5C of the atmosphere, we would expect the ocean to warm by the atmospheric warming * the ocean heat / the atmospheric heat / the ocean to atmosphere heat capacity ratio = (0.5C * 95%/5% / 1000) = (0.5C * 19 /1000) = 0.0095C If all the heat goes to the ocean this would be 0.01C. If the heat absorbed ratio is 90% this would drop to 0.0005C, if only half the ocean water is included in the short term ehat absorbtion, this would double. Overall 0.01C would probably be about the mean prediction.

By your graph the heat increase in the ocean is 10x10^22J, by the source I listed above, the heat capacity of the ocean is 5.6X10^24 J/Kelvin or J/C. This would imply a temperature increase of 0.02C, or basically right what would be expected. To try to tease out an extra 0.0005C to show if the amount of atmospheric warming is in the ocean or not is going to be difficult.

 
At 7:21 PM, February 23, 2014, Blogger JonJ said...

"To try to tease out an extra 0.0005C to show if the amount of atmospheric warming is in the ocean or not is going to be difficult."

Which of course is precisely why this particular tactic is being used. It will not convince any sceptics, but it provides an excuse to keep the money tap flowing for a few more years.

 

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