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TLP
climber
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Aug 31, 2014 - 12:16pm PT
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Jammer, there are other better places to get your answers. I recommend finding actual scientific articles, and reading at least the abstracts, and following the citation trail about specific things you're interested in. For example, you can just skim through a paper, even if it seems mostly incomprehensible, and when there's a statement relevant to what you want to know, and an author/year citation, then chase that one down and read the abstract. A lot of climate related publications are open, meaning you can download the full pdf of the text and figures without paying for it. And every journal makes the abstracts of every paper available on the internet. You'd be amazed at how quickly you can chase down a specific question by surfing efficiently.
As for your questions, it is true that there has been an overall and fairly gentle decrease in temperature for a few thousand years (with blips up and down), but the recent (1950-present) temperature rise is considered to be potentially alarming because it is quite rapid, and the best of our understanding is that the changes in climatic patterns will be large enough and rapid enough that there will be some pretty big costs in terms of "natural" events like droughts and/or floods and in terms of dislocations of populations due to changed conditions. For example, one of the possibilities is that rainfall might be significantly reduced, either in frequent enough occasional years, or overall, that many tropical areas that currently support large human populations based on primarily rain-supported (rather than primarily irrigation-supported) agriculture wouldn't be able to do so any more, and those folks are not just going to sit there and die, they're going to emigrate. Also, there are a lot of people, cities, etc., currently located where they're going to be greatly affected if the sea level rises only just a bit. When you get a lot of people suddenly moving to cities (see: Syria) or other countries (see: all the noise about immigration in the U.S.), there are problems.
It is absolutely true that there have been many huge climatic swings during human history (Ice Ages!), but the current human population is very dependent on things remaining pretty stable. I'm not imaging the folks in Alaska or Saskatchewan being enthusiastic about having 10 or 100 million immigrants from Bangla Desh or the Nigerian delta whose villages are soon to be under water regularly. Hence the concern.
If you want to know about the whole energy balance, probably your best source is the IPCC summaries. Somewhere in there is probably the equivalent of a pie chart for energy in and out. But the whole system is incredibly complicated, so you shouldn't expect one simple answer.
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TLP
climber
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Aug 31, 2014 - 12:32pm PT
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Oh, regarding the effects of the increase in ocean heat content, I agree with Ed that it isn't just any random guess, there are a few things that make some sense and others that probably don't make much. Though it's a lot of energy, the actual temperature increase (in degrees C, let's say) of the deep ocean water is a very small number. I don't know what it is, but if you go to the cited paper, they might say. Water has a lot higher specific heat than air, so a fraction of a degree temperature increase is a lot more heat content in water than in air.
Thus, the actual direct temperature effect on, say, plate tectonics, is certain to be negligible. The rocks that are hot enough to be semi-fluid are WAY hotter than the ocean waters will ever get to be, and they are insulated from the ocean floor by a lot of just plain solid rock, so there's nothing doing there. It also seems probable that the indirect effects, as in changes of circulation patterns, are so small as to be highly unlikely to trigger significant alterations of tectonic processes. If they did, well, yes, we might get more giant subduction earthquakes and tsunamis. But why bother speculating about these highly hypothetical issues when we know for sure that the surface ecology that we depend on is very sensitive to changes of the magnitude that we are seeing? I'll reiterate my carpentry analogy: who cares about the variation of a thousandth or two of an inch, when what we KNOW about is in the realm of an easily measurable fraction?
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Ed Hartouni
Trad climber
Livermore, CA
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Aug 31, 2014 - 01:24pm PT
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radioactive decay of Uranium in the core of the Earth is thought to keep it warm, but it is a tiny fraction of the energy that comes from the Sun.
As far as taking "a swipe" at you, jammer, I found that "teaching" on this thread didn't really get anywhere, basically the meritocracy of the STForum has more to do with climbing credentials than educational credentials. If my voice seems too harsh for you that's just part of participating. TLP is correct in directing you to other places to learn the basics... without the basics you won't stand a chance of understanding the issues, but I would suggest that it isn't "anyone's guess" as to what is going on, unless you don't want to consider the possibility that someone actually has taken the time to study what's going on and may know more about it than just "anyone."
The vast majority of the energy input to the Earth is from the Sun (this isn't the case for the so called "giant" planets, Jupiter, Saturn, etc... the majority of the energy for those planets is generated internally, except for Uranus). The figure above is a recent accounting of where all the Sun's energy goes...
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Chiloe
Trad climber
Lee, NH
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Aug 31, 2014 - 03:31pm PT
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Is your theory that, rather than eventually finding it's way somehow into the earth itself at least to some significant degree (or just staying in the ocean and not really heating it up all that much apparently), that it will eventually come sweeping back out of the ocean and into the air and incinerate everything?
That's nobody's theory. It sounds stupid, doesn't it? Jammer, you're coming on here with an odd mix of saying how much you don't know, but then declaring that scientists know even less than you. Ain't how things work, which I think is what Ed's reacting to.
Earth's crust transfers heat to the deep ocean, not the other way around; globally averaged heat flux is around 0.1 W/m^2. (Top-down cooling of crust is arguably the reason it sinks into the mantle, driving plate tectonics. That's another conversation we could have with the geologists on the forum.) As Ed's diagram depicts, the incoming solar radiation at the Earth's surface is more than a thousand times greater.
But while human activities are very rapidly changing the composition and thermal properties of the atmosphere, they've done nothing much to the crust-to-ocean heat flux that's been going on for hundreds of millions of years. The recently rising ocean heat content is largely caused by advection from that atmosphere-mediated system above.
Despite rising heat content the deep ocean remains cold, relative to most surface waters or the air just above. So the deep ocean heat is not going to heat the solid planet or the air; rather, a warmer ocean (or a return of historical circulation patterns) will less effectively pull down heat from the air. As Earth's energy imbalance increases the system has to get warmer; over the past decade ocean warming has bought time for the atmosphere but it could do the reverse in the future and cool the air less, so we'd get faster-than-trend warming. That's acknowledged in most recent studies of these topics including the CT14 and E14 papers I cited above.
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TLP
climber
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Aug 31, 2014 - 04:02pm PT
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Jammer, you'll get more informative and considerate answers to questions you pose if you would read the posts more carefully. I specifically made the point that all this deep ocean heat content is only a tiny bit of temperature change. How you got from that to "incinerate everything" is quite a leap of illogic. The current level of understanding of how the whole climatic system works is pretty well developed. There are some things that are pretty much totally random (volcanic eruptions), and some where there's a lot of science still to do (ocean circulation patterns and transfers to/from atmosphere), but the whole picture is nowhere near as sketchy as you seem to imply in your posts.
By the way, what I was recommending earlier was specifically NOT to just surf the internet in the usual way; that way, most of what you stumble into is going to be from the BS-osphere, whether pro or con, and you'll notice that the number of actual scientific sources cited in that realm is usually very very thin. My point was, use the standard scientific citation system (author, year, and the full titles will be in the References section at the end, you can then search on those words to find the paper itself, if there isn't a hyperlink in the pdf) to find your way to the real stuff.
Anyway, Chiloe puts the ocean temperature and geologic heat transfers in perspective. Like several of us have said again and again, what matters is the big terms in the system, not some fractions of Watts of energy. Ed's diagram puts that in perspective for the whole atmosphere and surface. If you must ask about what rate black-body radiation exited the Earth some 5,000,000,000 years ago, in the context of a discussion of 20th-21st centure climate, why not ask yourself, is this really relevant to today? Someday the sun will burn out and go cold, too, and it is safe to assume the climate will not keep getting warmer then; or Earth's orbit will degrade and it will fall into the sun and get fried: much warmer climate for a while. But these distant events are just not relevant. Curiosity about them is good, but not in the present context. It makes it seem like you think the current state of climate science is flawed simply because it doesn't address the pre-life history of the planet, or it can't place a date on the termination of livable conditions on the surface. That's clearly nonsensical, and probably not your point, but it's the impression you're inadvertantly creating.
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Chiloe
Trad climber
Lee, NH
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Aug 31, 2014 - 04:04pm PT
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Fortmental:
Can that rise in heat content be correlated with a sea level rise? Anyone done that math?
Yes, a number of people (not me!) have done that math. NOAA graphs their estimate of the thermosteric (temperature expansion) component of sea level rise as follows:
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TLP
climber
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Aug 31, 2014 - 04:37pm PT
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Must be because I don't know anything about physics ;)
Good one! :) from here too.
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Chiloe
Trad climber
Lee, NH
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Aug 31, 2014 - 04:41pm PT
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something besides your speculation, Chiloe
Which part of that did you class as my speculation?
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TGT
Social climber
So Cal
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Aug 31, 2014 - 05:48pm PT
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LOL!
Carry on.
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Norton
Social climber
quitcherbellyachin
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Aug 31, 2014 - 06:05pm PT
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I was just trying to point out that Ed was appearing to get tangled in words, reducing the power of his argument nearly to nothing, likely leaving many people with very much the wrong impression of things.
that is a strange observation
I have been reading this thread since the beginning and I see no difference whatsoever in Ed's postings, they are always clear, never "tanged in words" as you somehow deduce,
and very UNlikely leaving anyone with the wrong impression
Honestly, I have no idea how you came to those conclusions, does not make any sense
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Ed Hartouni
Trad climber
Livermore, CA
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Aug 31, 2014 - 07:12pm PT
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It is speculated that a long time ago the earth was a molten ball of rock. This is no longer the case.
Where did all that heat go?
it radiated away, see Stefan-Boltzmann law
http://en.wikipedia.org/wiki/Stefan–Boltzmann_law
Stefan's constant is a constant of nature.
Why does it dissipate at the rate that it does?
it depends on the area of the Earth and it's emissivity.
What is this rate?
I'll let you calculate that... if you need help looking up the emissivity then perhaps we can find it for you.
Is the rate effected by heat at the surface?
no, the entire body is in equilibrium, it is at the same temperature
you can derive the Stefan-Boltzmann law from the Planck's law of blackbody radiation.
It is done in the Wikipedia entry.
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rick sumner
Trad climber
reno, nevada/ wasilla alaska
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Aug 31, 2014 - 07:24pm PT
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Jammer-you've been doing a good job of questioning these guys. They'd like to keep you in the dark and baffled only by their b.s. and approved sources of b.s. However, you'll find relevant and understandable discussion of the issues on their unapproved source list. Below is a link to a guest poster on one of these sites discussing ocean heat content. Scroll down to " The layers of meaning in Levitus" for illumination. Figure 4 puts the scary terra joule increase into perspective. By the way, the earth radiates at the surface an average of .08wm2 from activity in the core and mantle.
http://wattsupwiththat.com/tag/levitus/
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Ed Hartouni
Trad climber
Livermore, CA
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Aug 31, 2014 - 07:59pm PT
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here is a link to Kelvin's calculation of the age of the Earth assuming nothing more than the
temperature gradient and an assumed initial temperature.
http://www.uh.edu/engines/epi1568.htm
Kelvin's cooling Earth is not in thermodynamic equilibrium, and the surface radiates as a black body at it's particular temperature...
this includes the internal heat which is largely due to convection of the mantle.
The conduction properties were deduced by the observed temperature gradient at the surface...
the result is 10s to 100s of million years old, and was a bit of a contested value, disagreeing with the
geologists and making Darwin a bit uncertain about his theory. But the issue was not resolved at the
time. In the end, the Earth is much older than Kelvin calculated, and there was time for Darwin's
theory to work.
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Ed Hartouni
Trad climber
Livermore, CA
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Aug 31, 2014 - 08:18pm PT
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the calculation gets more complicated when you let the system become dynamic...
the core is hot because of the radioactive decay
the mantel is also heated by convection
everything is radiating, there is the opacity of the material, so the temperatures vary through the
real Earth... there is emissivity to calculate, the whole nine yards...
the Sun is shining on the surface too, and that radiation goes "both ways" back out towards
space, and into the interior...
I'm being a dick? what's your problem.
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TLP
climber
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Aug 31, 2014 - 08:48pm PT
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By all means, let's keep the questions and answers coming. Here are a few for Rick, about his allegedly non-manure blog link:
Don't ALL of the figures show a huge increase in heat content of the oceans? If not, which one shows a consistent and lasting decrease (not just an annual or couple-year wiggle), either in the oceans overall or in any one portion?
Is an increase in heat content and temperature warming, or is it not warming?
Are the oceans part of planet Earth?
Does it follow that overall global warming is continuing unabated during the magical "Pause"? If not, why not?
What is the missing explanation between "I don't have any explanation for them, but they do not seem to be unusual [??? things change only minimally from 1955 to 1995, then zoom upward from 1995 to 2010, and this is somehow not unusual? what definition of unusual is this guy using?]."... and "It is clear, however, that the changes in heat content are not caused by CO2"
What? Can you refer me to where the justification for this conclusion is explained?
There are more questions, but these are some simple ones to start with.
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rick sumner
Trad climber
reno, nevada/ wasilla alaska
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Aug 31, 2014 - 09:22pm PT
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In a word TLP, no. What is the duration of the period of increased warming, what is the duration of accurate ocean temp measurements, What Is the spatial arrangement of sensors ? What does 0 to 2000 meters mean to you TLP? With the paucity of information, who is to say that the Earths major heat sink doesn't increase/decrease in heat content in cycles following increases/decreases of solar radiance reaching the sea surface? The uncertainty of proxy estimates is much higher than direct measurement, no?
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TLP
climber
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Aug 31, 2014 - 09:23pm PT
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I'm sure answers to the questions above will be coming along in due course, but just to remind (since memories are often shorter than 20 posts), the one single scientific source I cited and recommended was Gray et al. 2010, which I ended up reading because Rick himself posted up the link (and for the nth time, thanks! because it's a great review with tons of references on all sorts of related subjects). Only now this is being referred to as an "approved source of b.s." What changed?
Go and read whatever, but ask the same types of questions about the blathery blogs as you do about the scientific sources, and all will be well. For my part, I've learned a lot of interesting facts and seen a lot of interesting ideas in scientific papers, and pretty much zero of either from blogs. Just my take on the words I see on the screen.
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rick sumner
Trad climber
reno, nevada/ wasilla alaska
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Aug 31, 2014 - 09:31pm PT
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OftenTLP, as Ed graciously pointed out to me some time ago, their is much of interest discussed in the comments following the posted articles. Report back after you have read the whole thing.
Gray Et Al was a great resource. You don't have to reach the same conclusions to appreciate content.
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