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Paul, you are using a quote from the IPCC report that appeared on Watt's blog. Then you included his graphic that showed that the atmospheric temperature trend has decreased since 1998. The trend is still positive in that graph, but decreasing. I don't get your point you are trying to make with the first half of your #26316 comment. This is in response to my suggesting that there could have been a solar influence. Are you suggesting that mankind has somehow slowed the amount of warming or that there are indeed some natural causes?

About Greenland, you seem to be trying to link two different ideas: ice melt and mantle melt. You have Greenland's new-found buoyancy is "a symptom of its shrinking ice cap." You suggest that will lead to reduced pressure below the continent as the land mass rises. As a result, the lower pressure on the mantle "... can cause local melting of rock to form magma." Can cause? Hmmm. I wonder what the probability is. How much goes to cooling the mantle vs how much goes to increasing volume?

And what about how Greenland's ice has been thickening or there has been no change in the center. http://svs.gsfc.nasa.gov/stories/greenland/index.html

Greenland's glaciers have been accumulating for a long time. That extra pressure may have been partially relieved by the coastal melting recently causing the continent to rise. And with all the extra ice from this winter, it is likely to stop rising if not sink somewhat if the scientists are correct that the new-found buoyancy is due to melting ice. The glaciers on Greenland are quite old. For how many millenia has it been bobbing up and down?

I am also now lost as to how this magma/Greenland discussion relates to the missing heat in the oceans of the original post. If you point is that the amount of ice in the north is decreasing which puts cold water into the oceans, then you have to reconcile that with the south pole which has been doing the opposite.

Instead of attempting to fisk people using disjointed quotes, it would be nice if you just wrote down your thoughts in a coherent manner.

By the way, there has been another response on this topic elsewhere:

http://climatesci.org/2008/05/29/new-information-from-josh-willis-on-upper-ocean-heat-content/

.
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This is an interesting idea Paul, about the isostatic changes influencing the mantle and earthquakes, etc.
Didn't Iceland just have a 6.1....
Anyway, wish I could spend more time on this thread, but I did want to weigh in on this continuing reference to "increasing ice" here and there.

John,
...from your own nasa/greenland link on this "increasing ice."

"By comparing changes in ice thickness taken in 1999 to measurements made earlier in the decade, they concluded that the continent is giving up nearly 50 gigatons--that's 50 billion tons--of water per year...."
"As it turns out, the thickening ice in the center is itself evidence of disappearing ice over the rest of the continent."

...and in 2007 that number was about 150 gigatons/yr. (compared with 1999) [GRACE data].

I'd like to point out that the same phenomenon is happening in the Antarctic (explaining the often cited "increase" of ice in Antarctica -thanks RicS); but that is just true for Eastern Antarctica. For the continent as a whole, GRACE data shows a net loss of over 100 gigatons there also.

http://www.csr.utexas.edu/grace/
"Ice loss in Antarctica increased by 75 percent in the last 10 years due to a speed-up in the flow of its glaciers and is now nearly as great as that observed in Greenland, according to a new, comprehensive study by NASA and university scientists." -Last Modified: Tue Apr 15, 2008

RicS (and I think others), and now you John, casually throw these sweeping comments about "the ice" of the world increasing, when making some other point about the climate change debate. As an aside, in my replies, I always point out that the net figures do not support such statements. Perhaps this point gets lost in the effort to stick to the main subject, but it's long past time that "increasing icepack" anywhere should still be used to support claims that global warming seems to be reversing itself.

"Global Warming" is called climate change to prevent this misconception that cold events, or locally increasing ice levels, are a sign that things are getting better. In a warming world (with increasing water vapor) locally cold areas are the ones that will get the extra precipitation.
This explains: "As it turns out, the thickening ice in the center is itself evidence of disappearing ice over the rest of the continent."
===

In a warming world, the occasional cold event, or just an average year, probably will seem "record breaking" by comparison.
For instance:
Originally Posted By: JMR
....There were also stories about water reservoirs being close to running dry in the USA until this winter that was full of record breaking snowfalls.

Well, kind of....
http://www.sciencedaily.com/releases/2008/03/080314175834.htm
Quote:
U.S. Winter Temperature Highlights
In the contiguous United States, the average winter temperature was 33.2°F (0.6°C), which was 0.2°F (0.1°C) above the 20th century average – yet still ranks as the coolest since 2001. It was the 54th coolest winter since national records began in 1895.

It's not as if our reservoirs have recovered yet, or anywhere close....

So many of your points, based on these "recent cooling" arguments, are not standing up very well. You can't just dismiss the idea of Greenland's influence on ocean temperature by saying, "then you have to reconcile that with the south pole which has been doing the opposite."

Not the opposite (see above)....

...but thanks John, I learned a new word!
===
Ha, I had to look up fisking:
fisking: n.
[blogosphere; very common] A point-by-point refutation of a blog entry or (especially) news story. A really stylish fisking is witty, logical, sarcastic and ruthlessly factual; flaming or handwaving is considered poor form. Named after Robert Fisk, a British journalist who was a frequent (and deserving) early target of such treatment. See also MiSTing, anti-idiotarianism

I think this forum falls mostly on the "stylish" side of the fisking moire.
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Originally Posted By: samwik

Imran, I don't think we should criticize the knowledge level of folks on the fora here; this is a great place for everyone to learn more. Some people just have deep knowledge in some rare areas, other have broad or unique, shallow or esoteric... etc.
I think, even if it sometimes seems a bit tedious or pointless, that the diversity enriches things, in the long run.
We all try to be perfect, but with varying degrees of success.
smile


Indeed, a very fair point. I apologise for being facaetious. It was not warranted.

I did some extra digging around and can confirm the crustal thickness of the ancient craton which is Greenland is ~ 35-40km. However it does vary and heatflow from the mantle will also vary. The attached link provides is an 'interesting' view.
http://www.sciencedaily.com/releases/2007/12/071212103004.htm

But it hides a massive (and unfortunately typical) flaw in thinking. It is always seductive to use geological phenomena (which occur on timescales of hundreds of thousands to millions of years) to explain variation seen in the human timescale (years and decades). The ridiculous article gives an impression that some recent observation about variations in mantle heatflow can be used to explain annual or decadal variations in ice metling. The quotes below :

"Scientists have discovered what they think may be another reason why Greenland 's ice is melting"
“The complete melting of these continental ice sheets would put much of Florida, as well as New Orleans, New York City and other important coastal population centers, under water,” von Frese said.


This is patently absurd. It implies a link between the discovery of a geographcal variation in heatflow with a temporal variation in ice melt. Yes, whilst there will no doubt be geographical variation in heatflow which may mean glaciers in some areas move more quickly than other, the inference that recent annual changes in ice melt might be due to this are rubbish. It's just typical media reporting - implying there is something else we have to worry about.




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Yes, there has been a loss of ice in the Eastern Antarctic. This is likely due to volanoes warming the shallow ocean water. Your link said the likely cause was warmer ocean waters. Simply saying that the speeding up glaciers is due to global warming is misleading the reader. The air temperature trend in Antarctica has been negative for the past 30 years. It is also interesting to note that both the north and south have increased their ice extent significantly this year. The north is almost in the positive region. Greenland has had a problem with polar bears this winter due to too much ice between Labrador and Greenland.

None of this explains the missing heat though.

Global warming was supposed to affect the polar regions the most because the cold temperatures do not allow the air to hold much moisture. Without water vapour, CO2 was supposed to be a more dominant factor there. Antarctica did not conform to this theory, so they changed it to climate change. I will leave any more discussion about this to the 'human caused' thread.

Fisking, when done properly, refutes the examples given. Here, fisking has been to take sentences apart removing their context.

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ImranCan,
If I called your post "ridiculous," "patently absurd," and just plain "rubbish," would it carry as much weight as when you call a published article, about some scientific research, those same things?

btw...also from that article, fyi (...von Frese, leader of the project and a professor of earth sciences at Ohio State University) ...must be an elitist. smile
"Crustal heat flow is still one of the unknowns -- and it's a fairly significant one, according to our preliminary
results."

JohnMR,
You've not responded to any of the points about the most recent, comprehensive, GRACE data on net ice-mass gain/loss.
I'm still looking into the thermodynamics of CO2, but I could look through some old (Fall/Winter, '07/08) Threads to find the links, if you're interested. Please feel free to fisk my few, clearly defined, points (post #26337) above, about ice. I think that would be a lot easier than me trying to fisk that host of unrelated points you've made (again, and previously addressed) about ice extent, height, humidity, and location (and polar bears? LOL).

Melting came into this thread with the point about it cooling the oceans. Levitus (2003) has accounted for this in his Ocean Temp. calculations, as I've noted on another Topic.

But you're right; "melting theory/observations" is fairly off-topic, and should be continued elsewhere on either a new Topic or one of the older Topics on ice/melting/extent/etc., but not bears!

~Later
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Samwik

Quote:
This is an interesting idea Paul, about the isostatic changes influencing the mantle and earthquakes, etc.


It really is isnt it...
I didnt know there was so much relative information on the net
that points to this , but its easy to piece together once you find a place to start.

and then by applying unhindered physics to most problems there can be a solution found.


Quote:
Didn't Iceland just have a 6.1....


yes , 6.1 to 6.2 10 km deep.

Iceland sits on two tecktonic plates and is basicaly subjected to the same types of actions found along the tecktonic plates deep in the oceans.

I wouldnt want to be there myself , I can think of a better place to be.

I wish I had a map of greenlands land mass and a recent map showing the ice cover along with elevation data.

I have been troubled about the hot spots in general.

ie.. local heating might expand the locking mechanism that is holding large ice masses in place.

I know this sounds far fetched and even twilight zoney but just thinking about what would happen if a large ice mass were to lose its grip on the surrounding mountains or land mass due to expansion...and begin a quick slide into the ocean.

this type of event could set in place an enormous amount of depressurization to the earths mantle and the resulting magmatic expansion from the decreased pressures could caldera.

and I have wondered if this has happened before and that is why
I wish I had the mapps as mentioned above.

I just thought this might entertain some for awhile until I can find some resources of information.




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Originally Posted By: samwik

"Crustal heat flow is still one of the unknowns -- and it's a fairly significant one, according to our preliminary
results."


As an illustration of my point .... indeed I'm sure crutal heatflow is an unknown in understanidng ice distribution, thickness and glacier speed. The point I was making is that the article (note the use of the word 'article', ie. not published paper) IMPLIES that there is some link to climate change observations. Just read the opening sentence : "Scientists have discovered what they think may be another reason why Greenland's ice is melting".

Since when can a mantle "hotspot" which will have been there for a timescale only measurable in geological terms sudenly be stated as the cause for a very recent change in icemass in Greenland ?

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"This is within the margin of error for both techniques, each of which has its strengths and limitations." The GRACE study does not seem settled to me.

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Anyone mind explaining to me why Mar's glaciers are melting at the same rate as the Earth's?

---- some people say its because the sun is going through a regular cycle of expansion next it may contract a little......

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Glaciers receding? According to most folks around here on this forum, glaciers are increasing, and/or the measurements are inaccurate. Do you have a link to the rate on Earth and/or Mars?
...just kidding
....


SolarD,
If the sun really is changing our climate on a short time scale, shouldn't we take steps to counteract these effects if we want to maintain our civilization, which is so dependant on a moderate, predictable climate?

Controlling atmospheric CO2 levels presents an opportunity to "adjust the thermostat" of our planet (within a range that still preserves favorable ocean chemistry, etc.).

Regardless of whether or not the glaciers are disappearing (or perhaps because of it), shouldn't we apply our knowledge and try to manage our planet sustainably; and not be subject to the inevitable whims of planetary and cosmic forces?
http://www.scienceagogo.com/forum/ubbthreads.php?ubb=showflat&Number=25569#Post25569

...or perhaps... just pray to cosmic forces?

Thanks ...catch you later,
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I found this , and data , the data is in strips that offer the depth of the ice on greenland as a flyover that contains time , lat , lon , height , pitch , roll , heading.

but you can use excell and arrive at a estimate for yourself until you can program a visual representation yourself.

the downloaded files are in motion.quick they are ascii and can be renamed with the .txt extention and opened in excell.

the web site has some imagery of scanned data where you can see the land under the ice on greenland in the pdf file below.

Global Ice Sheet Mapping Orbiter
GISMO

here are a few of the charts and images with course plots of the data on greenland.

a pdf file of the greenland flyovers of GISMO sep 07

the nasa esto report has a section about GISMO in it.

apx half the way down in the file "Toward NEW Ice Sheet Measurements"

http://esto.nasa.gov/files/2007_ESTO_Annual_Report.pdf

has a 3D view of GISMO data.


someone remarked earlier in some post about trillion dollar projects.
I Truly believe that finding out just how much mass
could remove from atop greenland and the antarctic
and the results of that movement and most importantly the
speed of that movement would be a
feasible
use of a trillion dollars.

let the projects begin !!!


Last edited by paul; 06/05/08 05:18 AM.

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Regarding the NPR report,

From one of the guys who actually did the study, Josh Willis at NASA:

http://dotearth.blogs.nytimes.com/2008/04/01/ocean-cooling-and-global-warming/

"It is a well-established fact that human activities are heating up the planet and that global temperatures will continue to rise for decades to come. Climate change skeptics often highlight certain scientific results as a means of confusing this issue, and that appears to be the case with Mr. Gunter’s description of our recent results based on data from Argo buoys.

"Indeed, Argo data show no warming in the upper ocean over the past four years, but this does not contradict the climate models. In fact, many climate models simulate four to five year periods with no warming in the upper ocean from time to time. The same is true for the warming trend observed by NASA satellites; it too is in good agreement with climate model simulations. But more important than agreement with computer models is the fact that four years with no warming in the upper ocean does not erase the 50 years of warming we’ve seen since ocean temperature measurements became widespread….

"It is important to remember that climate science is not a public debate carried out on the opinion pages of newspapers. What we know about global warming comes from thousands of scientists pouring over countless data sets, conducting experiments to figure out how the climate works and scrutinizing every aspect of each other’s work."

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I was listening to some conservative talk-show host a few weeks ago on the radio ... can't recall who it was, but he had on a guest who noted that temperatures had actually gone done for a couple years and asked sarcastically exactly how many years of cooling had to take place before scientists acknowledged that GW was wrong.

My 16 yo daughter unprompted recognized how ridiculous this "argument" was before I had even finished explaining what I had heard. Really - it's asinine. I could guess the person making it was not a scientist - but probably it's just some tripe that's being uncritically circulated. But people don't have to be scientists to talk about science with an air of authority.

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Quote:
I was listening to some conservative talk-show host a few weeks ago on the radio ...


I have listened for the last year or so , and they seem to have
slowly been comming apart at the seams.

there is a big difference in the message they put across , and in the way the message is put across , from the time I started listening to recently.

honestly , I sometimes question if their sanity is in jeopardy!

I sometimes feel sorry for them while listening.

when these guys try to comment on GW , its like I'm experiencing your
favorite saying...comic book understanding of science...




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Originally Posted By: Canuck
Deep ocean measurements have not found any warming of the world's oceans (actually a bit of cooling). Where's all this extra heat, which the surface monitoring network tell us is in the air???
Just a physics, my dear Watson. Thermal capacity of oceanic water is roughly 5.000 times higher, then the thermal capacity of atmosphere. Furthermore, the main source of heating is just a surface. When surface is heated, the so called convection occurs in atmosphere, because hotter air tends to circulate in vertical direction.

But at the case of water in ocean exactly the opposite effect occurs: the heating of surface layers effectively inhibits the existing underwater convection, for example the thermohaline convection, which drives the Gulf stream.

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global warming is evident.. soon, plants would die because of severe intense heat. i think this planet is dying, we have to prepare. but not in our time though.

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