Torpedoing Of The Use Of The Global Average Surface Temperature Trend As The Diagnostic For Global Warming
By Dr. Roger Pielke Senior
There is a new paper by Gerald Meehl of NCAR and other collaborators that has been announced in the media; i.e. see in the International Business Tribune [h/t to Watts Up With That]
Global Warming on Temporary Hold Thanks to Deep Oceans
First, I am glad the authors implicitly acknowledge the importance of the ocean heat changes as the primary diagnostic of climate system heat changes, as I have urged in my papers
Pielke Sr., R.A., 2003: Heat storage within the Earth system. Bull. Amer. Meteor. Soc., 84, 331-335.
Pielke Sr., R.A., 2008: A broader view of the role of humans in the climate system. Physics Today, 61, Vol. 11, 54-55.
There are two major issues, however, with the new study that the authors [that the news article reports on] did not seem to recognize:
1. If heat is being sequested in the deeper ocean, it must transfer through the upper ocean. In the real world, this has not been seen that I am aware of. In the models, this heat clearly must be transferred (upwards and downwards) through this layer. The Argo network is spatially dense enough that this should have been seen.
2. Even more important is the failure of the authors to recognize that they have devalued the use of the global average surface temperature as the icon to use to communicate the magnitude of global warming. If this deeper ocean heating actually exists in the real world, it is not observable in the ocean and land surface temperatures. To monitor global warming, we need to keep track of the changes in Joules in the climate system, which, as clearly indicated in the new study by Meehl and colleagues, is not adequately diagnosed by the global, annual-averaged surface temperature trends.
The news article has the text [highlight added]
Global warming is temporarily on hold as the deep ocean currents and circulations absorb the sun’s heat before releasing it finally, scientists said on Sunday.
The study conducted by scientists at the National Center for Atmospheric Research (NCAR) and the Bureau of Meteorology in Australia was published in the Sept. 18 issue of the journal Nature Climate Change.The last decade saw an incessant growth in greenhouse gas emissions which ideally should have increased Earth’s temperature. However, Earth’s temperature didn’t increase vastly. Where was the “missing heat” going?To find out the mystery, Gerald Meehl, lead author of the study that revealed the connection between global warming and temperature hiatus caused by ocean’s heat absorption, and scientists at the NCAR in Colorado ran five simulations on a computer model that studied the complex interactions between the atmosphere, land, oceans and sea ice.The study revealed that temperature has already increased by several degrees in this century and will increase more in the coming days but the hiatus period will interrupt the increase. During this period, the missing temperature will lurk inside the deep ocean.“We will see global warming go through hiatus periods in the future, however, these periods would likely last only about a decade or so, and warming would then resume. This study illustrates one reason why global temperatures do not simply rise in a straight line,” said Meehl.
Kevin Trenberth, a study author and NCAR scientist, said: “… this study suggests the missing energy has indeed been buried in the ocean, the heat has not disappeared and so it cannot be ignored. It must have consequences.”
They found the vast area deeper than 1,000 feet (305 meters) warmed by about 18 to 19 percent more during the hiatus periods than at other times. Meanwhile, shallower global oceans above 1,000 feet warmed by 60 percent less than during non-hiatus periods in the simulation.
The study also revealed the regional signature of oceanic warming during hiatus periods. During a hiatus, average sea-surface temperatures decrease across the tropical Pacific, while they tend to increase at higher latitudes.
Meehl says these patterns are similar to those observed during a La Niña event.
“Global temperatures tend to drop slightly during La Niña, as cooler waters reach the surface of the tropical Pacific, and they rise slightly during El Niño, when those waters are warmer,” he added.
A final comment on this paper, if heat really is deposited deep into the ocean (i.e. Joules of heat) it will dispersed through the ocean at these depths and unlikely to be transferred back to the surface on short time periods, but only leak back upwards if at all. The deep ocean would be a long-term damper of global warming, that has not been adequately discussed in the climate science community.
If the deep ocean is a damper, then how do those tipping points work?
This study involved a climate model and can therefore not be trusted.
So let me get this straight: The computer model showed the heat was in the deep ocean? The COMPUTER MODEL?!?!?
So they measured the deep oceans over the past decade?
Trenberth found his missing heat with actual thermometers?
Wait, did they just assume the heat isn’t missing and plugged it into a model that estimates what the deep oceans must be doing to allow for the storage of this “misplaced heat”?
Could we have some observational data that backs this claim?
If the deep ocean were warming, I would suspect that it would also be expanding and the ocean level to be rising. Yet it is not.
Great job! This contortionism to save a hypothesis from the trash can will wear thin eventually, thanks to brave souls like yourself. Thank you.
One possible edit in bullet #1:
“that this should have been see.” seen?
[Fixed, thanks. ~dbs, mod.]
If the deep ocean is absorbing the heat instead of the surface then sea level must continue to rise. Where is the sea level rise to confirm their model? I don’t see it in the CU Sea Level Research Group plots or data.
Let’s hope they are right, we might well need that heat later!
The dog ate my homework.
People, you are missing the point. We all know we are killing the planet with excess heat trapped by our evil ways. This is settled science. Since we cannot find the heat anywhere we have looked it must be hiding. The best place (for our purposes) for it to hide is in the deep ocean where no one can prove that it is not there. Therefore our models looked, and there it was. Our findings are robust, and anyone who says otherwise is a shill for big oil and is committing crimes against humanity. We are watching and taking names. Climate Justice will find you. /sarc
Garry says: September 20, 2011 at 12:58 pm
I might agree with the sentiment, but how does this advance the discussion?
Just wondering do any scientists actually do experiments anymore? A computer model based on the predictions of another model is proving black is black. If heat is being sequestered deep it would have to be below a thermocline in order to stay deep and even so it would transfer heat from the hot areas to the cold areas or has thermodynamics changed recently.
Would it be possible for one of these “sceintists ” to actually do an experiment and measure the heat transfer from Argo Data . If this transfer and sequestering is really happening it has to have a footprint somewhere, Scotty has not been beaming the heat down there for G*** sake.
“The study revealed that temperature has already increased by several degrees in this century…’
Oh, really!? Even if you take “this century” to mean “this past century” (i.e. the last 100 years) instead of “the 21st century”, I don’t know of any source that reports over a degree of warming of any component of the climate system, especially the oceans.
“Global warming is temporarily on hold as the deep ocean currents and circulations absorb the sun’s heat before releasing it finally, scientists said on Sunday.”
Whew, for a second there I thought that: Global Warming was temporarily on hold as the deep ocean currents and circulations absorb the sun’s heat before releasing it finally, scientists said, on Sunday.
Come to think of it, it was a little warm on Sunday.
MattN
I watched ‘The Day After Tomorrow” over the weekend and the hero of that film is a paleoclimate climate modeller. Their work is very important.
“They found the vast area deeper than 1,000 feet (305 meters) warmed by about 18 to 19 percent more during the hiatus periods than at other times.”
They found this IN THEIR COMPUTER MODEL, not in the world. It is a rank perversion of the language of science, which is premised on the priority of observation over theory and modeling. They have booted observation out of town and are pretending that models ARE observation.
I’m mystified by this. What is the source of this increased heat content of the ocean? If the atmosphere does not have a higher energy content, where did the heat energy in the ocean come from? Is Trenberth suggesting that CO2 stops the ocean from radiating energy in the first place? If the atmosphere does have a higher energy content, why hasn’t the temperature of the atmosphere increased?
So……..all of a sudden the deep ocean decided to act as a heat sink
Out of the blue,and for no known reason….just all of a sudden it started doing it
when it never has before
What a bunch of crock…..
The deep ocean would have been retaining more heat all along….since the beginning
….it wouldn’t just start doing it when it’s convenient for climate scientists to hide the heat
The other possibility is that the rapid warming in the 1990s was due to the opposite, and now we have the normal warming
I thought science examined observable data and tried to develop a theory for it not the other way around. Has this deep ocean heat been observed?
Wouldn’t the extra heat also show up in sea level rise due to thermal expansion?
Can we henceforth refer to this as “Trenberth’s Nature Trick”?
I’m just a layman, but can someone tell me HOW the heat remains “sequestered” in the deep oceans? IIRC from high school physics, a warm body, even with insulation, will radiate its heat to cooler surroundings. Since the supposedly warmer water is surrounded by cooler water, why would that not happen in this case — or is the warmer water trapped in some sort of huge Thermos bottle?
Wouldn’t the heat in deep waters be more likely caused by thermal vents and underwater volcanos?
There is a particularly valuable aphorism these guys apparently were not taught in their youth: Oh, what a tangled web we weave…