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NASA Study: Ocean Abyss Has Not Warmed
submitter bigwheel sends this excerpt from a NASA news release:
The cold waters of Earth's deep ocean have not warmed measurably since 2005, according to a new NASA study, leaving unsolved the mystery of why global warming appears to have slowed in recent years. Scientists at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California, analyzed satellite and direct ocean temperature data from 2005 to 2013 and found the ocean abyss below 1.24 miles (1,995 meters) has not warmed measurably. Study coauthor Josh Willis of JPL said these findings do not throw suspicion on climate change itself. "The sea level is still rising," Willis noted. "We're just trying to understand the nitty-gritty details."
Lots of Ice melting. Could be that all the energy is going into phase change right now.
A republic cannot succeed till it contains a certain body of men imbued with the principles of justice and honour.
Because that is what every new report is field of science that we don't actually understand.
And we don't. As regards global climate we have models and data but we don't really understand what is going on here. We never have. And that isn't to say that AGW isn't happening or is or anything one way or the other. But rather that it is extremely complicated and extremely confusing.
This article is going to make the anti AGW people feel vindicated just like the walrus thing made the pro AGW people feel vindicated. It is going to go back and forth. I'm sure tomorrow or the next day we'll get another report of something that backs up the AGW side and this article will just be forgotten.
That is just the politics. For those of us that don't care about the politics... this should just be interesting.
So what we get here is that the heat predicted by the models is still missing.
That is interesting. So we should keep looking for it. And until it is found those supporting the climate models that require that heat to be somewhere really should be some what humble about their position until the heat is found. Which is reasonable. But assuming they don't want to do that for whatever reason... Whatever. We're going to respond to this issue however makes best sense to each of us.
For me... I'm going to take with a grain of salt anything someone says when they don't show what I feel to be a reasonable amount of humility on an issue they cannot claim to fully understand. By all means... form your own opinions.
For me... this is just another interesting data point. I await more.
I've decided to stop wasting my time responding to AC trolls/sockpuppets... so if you want a response from me... login.
Yesterday it was about the top layer, today about the deeper layers. Oceans are big and varied, you know.
My understanding is that the transmission of heat would not be perfect and so if there were heat being sinked in the rock there should be residual heat in the water. The oceans are not after all super conductors. They must have a high resistance and that resistance would mean they would warm if they were subjected to a net increase in heat.
I am no expert either of course... so many that is all crap. :-)
It is very difficult to discuss this issue because about 30 percent of people only care about answers that prove AGW and end the discussion and another 30 percent of people only care about answers that disprove AGW and end the discussion. That means about 60 percent want AGW to not be talked about but rather concluded one way or the other. That leaves less then 40 percent that are actually curious about it and want to know more.
This makes posing questions and looking into the issue problematic because the 60 percent will attempt to shut down any discussion one way or the other. Those 30 percent figure are of course completely pulled out of my butt and they will shift around radically from one moment to the next. In some cases, I've been pretty sure it was over 90 percent of people in a discussion that simply didn't want anyone to talk about the issue at all. Just hordes of people shouting and browbeating everyone to try and silence everything.
I've decided to stop wasting my time responding to AC trolls/sockpuppets... so if you want a response from me... login.
They're obviously getting a rebate on rocket fuel from big oil. Deniers the whole bunch of them!
Again, I've repeatedly explained that the power needed to cool the walls is irrelevant, and that it isn't required to be constant.
Again, why does Jane think if something doesn't affect the power out, it can't affect the power in? For example, black body "power in" depends on the chamber walls even though "power out" through that boundary doesn't depend on the chamber walls.
Since we agree that "electrical heating power" goes to zero when the chamber walls are also at 150F, has Jane also noticed that "net heat transfer" also goes to zero when the chamber walls are also at 150F?
Isn't that a weird coincidence? So why does Jane keep using an equation that depends on "electrical heating power = radiative power out" without even writing down an energy conservation equation to try to justify that claim? Has Jane even considered the possibility that if he applied conservation of energy, he'd find that electrical heating power really is determined by net heat transfer, rather than "radiative power out" which stays constant even if the chamber walls are also at 150F?
If there's no net radiative power coming in, that must mean all the "power in" from the chamber walls just goes back out. That would yield a net of zero. But as usual Jane didn't write down the power in = power out equation showing these terms before they supposedly cancel. Is this what you mean, Jane?
Draw a boundary around the heat source:
Jane's power in = electrical heating power + radiative power in from chamber walls
Jane's power out = radiative power out from source + radiative power from chamber walls, re-emitted back out
At steady state, Jane's power in = Jane's power out:
electrical heating power + radiative power in from chamber walls = radiative power out from source + radiative power from chamber walls, re-emitted back out (Jane's equation?)
Jane, is that your equation for required electrical heating power? By "NO NET RADIATIVE POWER COMING IN", are you saying "radiative power in from the chamber walls" = "radiative power from chamber walls, re-emitted back out"?
Allow my naivete to shine: What's the temperature of all of the rock that water is in contact with, and what's its thermal capacity relative to the water? Could it be that it's slow to warm as you need to warm all the rock it's in contact with?
Without getting technical, heat capacity is called "specific heat", and water has a relatively high specific heat. Using similar units, here are some examples:
Granite: 0.79
Basalt: 0.84
Sea Water: 3.93
So the heat "storage" capacity of liquid water is, very roughly, about 4.8 times that of rock.
Also just a phase change, from ice to water or vice versa at the same temperature, requires (or releases) a surprisingly large amount of energy.
It is not really an issue of thermal capacity. The huge difference is that solid materials like rock, silt, etc. do not have convection currents (or other forms of mixing). Heat transfer via conduction alone is very much lower. If the oceans were magically raised by 1 degree overnight, it would take months to years to warm the underlying floor by half a degree 5 meters below its surface (depending upon the material)
Water has a higher heat capacity compared to just about everything else when considered on a unit mass basis, but a few meters of ocean floor cannot begin to approach the thermal capacity of the ocean.
Allow my naivete to shine: What's the temperature of all of the rock that water is in contact with, and what's its thermal capacity relative to the water? Could it be that it's slow to warm as you need to warm all the rock it's in contact with?
You are correct to label your question naive :-)
The average ocean depth is about 4000 m, so the depth being looked at here (just under 2000 m) isn't typically in contact with rock at all. That is, if you demarcated the 2000 m depth line it would intersect very little ocean floor, and that just off the edges of continental shelves. These are pretty much the "mid-depths" we are talking about.
Furthermore, rock is both a) insulating (compared to water) and b) of relatively low heat capacity (compared to water).
Water has a heat capacity of about 4 kJ/kg*K, which is to day it takes 4 kJ to raise 1 kg of water 1 K in temperature. A typical rock (granite, say, although most others are similar) has a heat capacity of 0.8 kJ/kg*K, so rock is both less able to transport heat and less able to absorb heat than water.
Oceans are far more important to the heat balance of the Earth than the air is. Consider the scales. Earth has 5E18 kg of air, and 1.4E21 kg water, and water has 4 times the heat capacity of air, so the thermal mass of the oceans is about 1000 times greater than that of the air (I'm actually surprised it's not more than that, but I've confirmed the numbers from a couple of different sources.)
Given that AGW is adding about 1.6 W/m**2 to the Earth's heat budget, consider a typical square metre of ocean surface, below which is a water column 4000 m deep with a mass of 4E6 kg. That 1.6E-3 kJ/s*m**2 has the capacity to raise the temperature of that water column by 1.6E-3/4*4E6 = 1E-9 K/s. Which doesn't sound like much until you realize there are 3.14E7 s/year, so ocean warming, all else being equal, could be as much as 0.03 K/year, or 0.3 K/decade, or 3 K/century.
These are pretty appreciable numbers, and give a sense of the utility of precise ocean measurements as a way of getting at AGW, because we should be able to see a characteristic depth profile of temperature developing over time that would allow us to infer the additional radiative forcing very directly.
Blasphemy is a human right. Blasphemophobia kills.
Except global temperatures have not plateaued and continue to rise. The rate of the rise changes but it is continuing to rise. The "plateau" is only spin using a very crude line from a peak in 1998. http://www.skepticalscience.co...
The warming cannot be explained by an inter-glacial. Dumping millions of years of stored carbon into the upper atmosphere is not surprisingly having an effect on the climate. Land use changes, clear felling, road and city concreting do not help either.
This study is going to help refine the calculations of where heat is stored and how it changes over time but don't delude yourself that this is not related to human activity. Even most deniers have stopped denying that.
I believe that climate modelers have identified over a thousand feedbacks, many positive, many negative. The problem is that this really and truly the great unknown of climate models -- The early models (and probably later ones, since the results are somewhat consistent in overall sensitivity) pretty much all seem to be have estimated sensitivity to the CO2 as much larger than unity. From radiation emissivity calculation alone, a doubling of CO2 should raise average temp. by 1.1 def C, the earlier climate models that were used in the the IPCC reports, etc. all modeled the actual sensitivity as well in excess of 1 (which is why predictions were 3-7 degrees IIRC), i.e., more positive feedback than negative.
Positive feedback is well known in dynamic systems as a source of instability (although it is very useful in active control systems).
Personally, given that the known climate history is mostly stable over long periods of time, I would expect the overall sensitivity to be less than unity. I.e., if it was significantly over unity (unstable) the planet should have already been cooked or frozen by now.
I oversimplify, because real systems are non-linear, i.e., at near "normal" mid-range temperature, the net feedback could be positive, but a more extreme temperatures, the net feedback could be negative. But, this would tend to cause a meta-stable system in that the climate would initially overheat or freeze, then tend to stay at that extreme and require a significant external perturbation to flip the climate back to a "normal" mid-range (or even the opposite extreme). I suppose that this could arguably be a pretty considered a good match to the accepted temperature of the earth.
In the atmosphere there's a situation: The weather all happens down near the surface, in a region called the troposphere. Here the density/temperature gradients can result in instabilities, where a parcel of air that is, say, lighter than its sourroundings can become MORE ligher-than-its surroundings as it moves up (and vice-versa). Above that is another (set of) layer(s) called the "stratosphere", where everything is most stable right where it is. Nothing very exciting happens there except when something coming up REALLY fast from below coasts up a bit before it stabilizes and moves back down.
The oceans do something similar, but upside down:
Water has an interesting property: Like most materials it gets more dense as it gtss colder - but only up to a point. As it approaches freezing the molecules start hanging out in larger groups, working their way toward being ice crystals. The hydrogens on one molecule attract the oxygens on another, and because of the angle between the hydrogens bondended to the oxygen in each molecule, the complexes are somewhat LESS dense than liquid. As a result, with progressively lower temperatures the density reaches a maximum, then the water begins to expand again. When it actually freezes it is so much less dense than near-freezing liquid that the ice floats. With fresh water the maximum density happens about 4 degrees C. Salt disrupts the crystalization somewhat so the maximum density is a tad cooler (and varies a bit with salt concentration - and thus depth), but the behavior is similar.
The result is that, when you have a mix of cooler and hotter blobs of fresh water, the water closer to 4 degrees sinks and that farther from it rises. The result is that, absent a heat or impurity source below, the bottom (and much of the volume) of a deep lake tends to be stable, stratified, water at about 4 degrees year around, while all the deviations from it and "weather" activity is in no more than about the top 300 feet: Wave action, ice, hot and cold currents, etc. are all above the reasonably abrupt "thermocline" boundary. Below that things are very slow, driven mostly by things like volcanic heat. (Diffusion is REALLY slow in calm water. It takes decades for, say, dissolved impurities to move a couple inches.)
The ocean is much like that, too, but a little cooler and with some temperature ramps spreading out the thermocline due to variations in salt concentration.
So global warming/cooling/weather, whatever would NOT be expected to affect deep water temperatures. This would all be happening in the top few hundred feet. If, say, the ocean were heating up without the surface water temperature changing, this would take the form of the thermocline gradually lowering near the equator and/or rising near the poles, rather than the deep water becoming warmer.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
Climate: (noun) - anything in the sky or seas that can be twisted to support the claims that the world will end if we do not all pay higher taxes and give governments more power over individuals.
Weather: (noun) - anything in the sky or seas that might be twisted into an argument that governments do not need more money and power in order to "save the planet"
Examples of proper usage:
1. Hurricanes: when large and devastating, like Katrina, they are climate and proof of global warming, but when absent for a record-setting period of time they become weather and anybody who cites them as evidence of non-warming is an IDIOT
2. Temperatures: when high in a place like California, they are climate and proof of global warming, but when very low in a place like the midwest and explained as a "polar vortex" they are just weather and anybody claiming temperatures matter is an IDIOT who doesn not "get" the difference between "climate" and "weather"
3. Droughts: When hitting California worse than younger citizens remember in their short lives they are climate and proof of global warming, but when people are reminded that they have happened many times before and when evidence shows that the current one too is tied to El Nino/La Nina weather patterns they are....... um...... still climate and proof the world will end if we do not abandon the free market, personal liberty, etc (when something is a disaster that can be used no matter what, it remains climate)
Bingo. Anti-AGW people go "ah hah! It's not warming see! Nothing to worry about!"
Which should actually be about as comforting as discovering that your septic tank has gone from full to empty without any actually needing to pump it out.
Whoa... Yet another one that simply doesn't get science at all.