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#16785 - 10/26/06 04:04 PM Ocean array acts as climate alert
DA Morgan Offline
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Registered: 10/17/04
Posts: 4136
Loc: Seattle, WA
Measurements from a network of monitors stretching across the Atlantic Ocean could offer an early warning of "sudden climate change", scientists have said.

Underwater instruments measuring the temperature and salinity of seawater will detect any change to currents that regulate Europe's climate, they said.

A UK-led team of researchers said the data offered the most detailed picture of the ocean's circulation patterns.

The first set of results were presented at a climate conference in Birmingham.

Source:
http://news.bbc.co.uk/2/hi/science/nature/6081458.stm
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#16786 - 10/26/06 09:59 PM Re: Ocean array acts as climate alert
RicS Offline
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Registered: 03/26/06
Posts: 310
Loc: Sydney, Australia
G'day Dan,

And on what do they base their comparison? It provides a detailed snapshot of circulation but how do you detect a change if you don't know what is a normal or even cyclic pattern. Two different things, in my view.

I always worry when a valid scientific endeavour - in this case the study of ocean circulation, water temperature at various depths and salinity - is shoehorned into an "early warning system" when it clearly has no ability to do any such thing unless those that monitor it are very confident indeed on what is the norm.

Being a news article it was very difficult to discern how they were comparing the data that involved very sophisticated arrays up to 5 kms in length with some measurements taken in 1957 when there would not have been any ability to take similar measurements. I also noted that they are only going to do this until 2008. What is the point of that? I would have thought that the readings every year for 25 or even 50 years may be very useful in the study of ocean circulation.

Actually the idea of retrieving the units once every 12 months rather than having some method of just uploading the data periodically seems to not be the best design for such a project, unless current technology only lasts 12 months or so in the conditions of the sensors. Once again, being a news article, none of this information that might have made this interesting is absent.

Regards


Richard
_________________________
Sane=fits in. Unreasonable=world needs to fit to him. All Progress requires unreasonableness

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#16787 - 10/26/06 10:20 PM Re: Ocean array acts as climate alert
samwik Offline
Megastar

Registered: 10/10/06
Posts: 1164
Loc: Colorado
Hiya Richard
"We concluded that there was some evidence of a small decrease but not as big as we reported in the Nature paper last year," Professor Bryden observed.

The findings were based on five historical "snapshot" measurements of overturning in 1957, 1981, 1992, 1998 and 2004.


As I read this link (above) earlier today, I could already hear you over my shoulder pointing out all the weaknesses of the study. (Thanks...)(I think)?
Or at least the weaknesses we can glean, or suppose, based on the news article.

As I read, I wondered about the "truth" that could be derived from 5 snapshots. Not very good odds.

Still, the infant global climate science continues to hone it's acuity and understanding with studies like this.

I'm just amazed that there were 5 other snapshots that even existed! ...and I know what your going to say about those too; but at least they exist!

Cheers!
~Sam
_________________________
Pyrolysis creates reduced carbon! ...Time for the next step in our evolutionary symbiosis with fire.

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#16788 - 10/26/06 10:47 PM Re: Ocean array acts as climate alert
RicS Offline
Senior Member

Registered: 03/26/06
Posts: 310
Loc: Sydney, Australia
G'day Sam,

Hey, I've had an impact!

I have no problem with such studies. Ocean circulation is important to the understanding of our planet. Not all science has to be immediately of economic benefit (although I wonder about studies that include such things as mobile phone use and fertility - see other current thread).

I actually think my post was being written while yours ended up being posted and so your predictions were not far off at all. Is that a good thing or a bad thing?


Richard
_________________________
Sane=fits in. Unreasonable=world needs to fit to him. All Progress requires unreasonableness

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#16789 - 10/26/06 11:39 PM Re: Ocean array acts as climate alert
DA Morgan Offline
Megastar

Registered: 10/17/04
Posts: 4136
Loc: Seattle, WA
We can compare current salinity with that at past times by taking core samples. And at those same points in time we can determine, with some degree of accuracy, the climate.

Some assumptions must be made.

And with time they will be modified and become increasingly more accurate.

What Europe is worried about is the mid-Atlantic conveyor stopping. If it does Europe, as we know it ends for the rest of the lifetimes of all alive. Not a happy thought.

We know how to stop it. We don't have a clue how to restart it.
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DA Morgan

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#16790 - 10/27/06 10:54 AM Re: Ocean array acts as climate alert
RicS Offline
Senior Member

Registered: 03/26/06
Posts: 310
Loc: Sydney, Australia
G'day Dan,

It isn't all that easy to stop. It took a huge amount of fresh water to stop it for quite a limited period about 8,000 years ago and even then it seems that it was working again in about eight months. But it did have an impact on Europe for a while. I personally would not want to have been one of the tribes people that had gone to the trouble of having made summer clothes only to find we were stuck with basically very cold conditions for another century or so.

I don't think you can easily compare the records now being gathererd with pretty much anything. They can be compared with each successive year in the future if they keep it going long enough and I hope they do but core samples provide only limited information (and I'm a little confused here - sediment core samples or ice core samples - neither seems to be a good fit for temperature and salinity of the Atlantic in the area of the current recording over the last 100 years).

If the inter-ocean conveyor were to falter then I'd guess we'd have a reglaciation throughout the Northern Hemisphere. I'd be more worried if I lived in Canada or the US than Europe. The conditions in Europe, to some extent and set up to cope with snow and cold but that is not true for much of the US. I'm not sure you could get the conveyor to change in such a way that it stopped warming Europe but continued to work for the rest of the world and heat exchange is necessary somehow so I can't see it stopping. It does not stop during a glaciation or even during a reglaciation so it does not seem to be the trigger for a reglaciation. And I can't see how it could possibly work to cause a deglaciation.

The whole process smacks of "The Day After Tomorrow" and the science was a bit suspect in that movie. It made a good science fiction movie, emphasis on fiction. There is an explanation for the grass chewing woolly mammoth and the sudden extreme freezing that there does seem to be evidence for during the instability going into a reglaciation. It seems that jet streams are not only latitudinally unstable but can be altitudinally unstable during reglaciations. If a jet stream dipped to the point where it touched or gets very close to land, you get very fast air movement with incredibly cold air. Snap freeze! It seems that a jet stream, if it dipped towards the land would do so in the warmest area. That would be a lake. Thus you could get a jet stream ripping off the frozen skin of a lake, vacuuming up a large quantity of water into fine droplets, freezing these in the air and building up a block of ice that would snap freeze anything in its path.

While the hurricane in the South Atlantic is called a cold hurricane it does not act like a hurricane in several vital areas. It certainly does not produce the sinking of super cold air in its centre like they showed in the movie.

I'd be interested if you could explain what you meant by core samples, Dan. Personally I cannot see how they would determine climate in comparison to what this discussion is about. And using sediments or ice cores to determine world climate is a whole other topic.


Regards


Richard
_________________________
Sane=fits in. Unreasonable=world needs to fit to him. All Progress requires unreasonableness

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#16791 - 10/27/06 07:15 PM Re: Ocean array acts as climate alert
DA Morgan Offline
Megastar

Registered: 10/17/04
Posts: 4136
Loc: Seattle, WA
RicS wrote:
"It isn't all that easy to stop. It took a huge amount of fresh water to stop it for quite a limited period about 8,000 years ago"

Compare what it took to stop it the last time to the freshwater melt from Greenland.

Post the results and the sources here for everyone to examine.
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DA Morgan

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#16792 - 10/27/06 10:09 PM Re: Ocean array acts as climate alert
RicS Offline
Senior Member

Registered: 03/26/06
Posts: 310
Loc: Sydney, Australia
G'day Dan,

No thank you but thanks for the invitation. You posted a news article. I've commented on the news article and even went to the trouble of at least finding the NASA web page that provided detail of the research which was the topic of the news article. Post some research and I will do likewise.

The two lakes that collapsed into the North Atlantic were truly immense. The barrier that held it back was up to 2,000 metres high and the lakes covered a much larger area than Greenland. That and Greenland does not seem to be lossing all that much land ice and there really is no comparison. It's not a topic that greatly interests me but feel free to continue with your own comments.

There is also a question of the relevance of major fresh water melts at the end of glaciations and the fact that they do not seem to stop the ocean conveyor system of heat transfer. If they did, then there would be a mechanism that would be self limiting in the world flipping to an interglacial period. It would warm up, the ice would melt into the North Atlantic. The conveyor would be disrupted, returning a very large area of the Northern Hemisphere to a much colder condition and, hey presto, no interglacial period.

Thus far, all of your news articles in relation to Arctic ice coverage have included the detal that overall the loss of locked ice is small or perhaps non existent. So just how much sea ice melts during a particular summer (and the one just gone was nothing like the severity of the previous one) does not contribute to the addition of extra water into the system. If there is research that contradicts this, feel free to cite it or provide a link to it. Please note I'll happily ignore further news articles.

This is all getting rather stale. You post a thread with a news article. Someone, often myself responds to it. You then rubbish the opinions of anyone that does respond to it, claim that no research is ever quoted to back the counter position, even though the whole thing was not based on research in the first place but rather a news article, and it degenerates into a thread that does not discuss the science of climate or any particular aspect of it. I'd rather not perpetuate this system.

Frankly, I don't have the time to do this over and over. But put forward some science or a considered argument or even postulate a point of view and as long as you agree to stick to the topic, I'll happily participate, provide citations and the like.


Regards


Richard
_________________________
Sane=fits in. Unreasonable=world needs to fit to him. All Progress requires unreasonableness

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#16793 - 10/27/06 10:40 PM Re: Ocean array acts as climate alert
DA Morgan Offline
Megastar

Registered: 10/17/04
Posts: 4136
Loc: Seattle, WA
RicS wrote:
"No thank you but thanks for the invitation."

Why not? Afraid of what I know to be true? That we are well on our way to repeating history?

Buck up. Show some courage. Hit google. Post the results.

What do you mean you don't have time to do it over and over ... you've yet to do it once.
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DA Morgan

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#16794 - 10/27/06 10:43 PM Re: Ocean array acts as climate alert
dehammer Offline
Megastar

Registered: 03/23/06
Posts: 1089
Quote:
Originally posted by RicS:
There is an explanation for the grass chewing woolly mammoth and the sudden extreme freezing that there does seem to be evidence for during the instability going into a reglaciation.
perhaps one of you could help me on this. wasn't the wooly mammoth frozen at about the same time as a super volcano eruption in north america. the distance would be too far for the ash and stuff to reach, but the sulpher dioxide could have been thick enough when it reach siberia to have caused a major snowstorm in late spring, the time i believe the mammoth was frozen. All it would have required was for the mammoth to have been in a simi sheltered gully or valley, when a large amount of snow fell on him to choke him quick enough to keep the flower or grass he was eating to not be swallowed, and a wet spring thinned coat would have transfered the body heat away quick enough to stop the stomack acid before it could destroy the stomack content.
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#16795 - 10/27/06 11:02 PM Re: Ocean array acts as climate alert
RicS Offline
Senior Member

Registered: 03/26/06
Posts: 310
Loc: Sydney, Australia
G'day dehammer,

The woolly mammoth in the New York Museum isn't the only one that was found like that by the way.

It could have had a heart attack I suppose. But the point about how it was found was that it did not appear to be in particular distress. It just ended up in a block of ice. Even -80 isn't cold enough for the incredibly good insulated mammoth to snap freeze so that the partly chewed material stays in its mouth. I'd dare say a human would still have time to swallow and could live for a few minutes naked at those temperatures with a screaming wind on top.

Regards


Richard
_________________________
Sane=fits in. Unreasonable=world needs to fit to him. All Progress requires unreasonableness

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#16796 - 10/28/06 02:58 PM Re: Ocean array acts as climate alert
dehammer Offline
Megastar

Registered: 03/23/06
Posts: 1089
that would be true, but what if his throat was restricted by the snow, blocking the passage of the material. rather than freeze to death, it might have choked to death, after having been knocked unconcious by the force of the blow from the snow hitting its head. the cold temperature would have reduced any flow to that area, preventing any sign of a bruise. As i understand it, it had lost its winter coat, meaning it was not as well insulated as normal. that would have allowed it to lose heat much faster when it turn to a deep freeze again. about the time hyperthermia would start to set in, here comes the avalance.
_________________________
the more man learns, the more he realises, he really does not know anything.

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#16797 - 10/28/06 06:57 PM Re: Ocean array acts as climate alert
RicS Offline
Senior Member

Registered: 03/26/06
Posts: 310
Loc: Sydney, Australia
G'day dehammer,

That's a lot of what if's. The point is that it was not a single animal found. If it was then some truly bizarre reasons may actually be correct. But there have been several. Mammoth carcases have been found (and most often eaten) for centuries. The instant death, seemingly in positions that did not suggest its manner of death and including such strange things as still chewing, suggest that something occurred that caused the animals to die where they were instantly. Makes it a bit harder to come up with a logical reason.


Regards


Richard
_________________________
Sane=fits in. Unreasonable=world needs to fit to him. All Progress requires unreasonableness

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#16798 - 10/28/06 07:19 PM Re: Ocean array acts as climate alert
samwik Offline
Megastar

Registered: 10/10/06
Posts: 1164
Loc: Colorado
Maybe it wasn't quite as instantaneous as we imagine. Thinking of the way herbivores eat, don't they chew for a long time? And they don't sleep for long stretchs either, but doze (I think).

I chew much longer than average and I don't sleep for more than 3-4 hours straight (sorry, TMI?); and I find myself falling asleep while chewing.

Maybe these mammoths were frozen overnight (or at least over a few hours).

Another idea is that if I were a mammoth, faced with the feeling i was about to freeze to death, I might start eating (hoping to generate a little warmth from bacterial decomposition). -i'm such a smart mammoth!

smile smile
~samwik

P.S. Isn't this a good example of a thread that maybe should be moved over to "not-quite-sci;" or maybe duplicated over there. After duplication, that new thread could go on speculating, and the this original could get back to discussing whatever this thread started with -ice?

AND it'd be nice to put this "P.S." in a side-bar & also add it to the other thread re: (now I can't go look at the title without losing all my typing here, so I'll call it) Climate Change Forum Modifications

Hint, hint....

smile ~S
_________________________
Pyrolysis creates reduced carbon! ...Time for the next step in our evolutionary symbiosis with fire.

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#16799 - 10/28/06 07:25 PM Re: Ocean array acts as climate alert
RicS Offline
Senior Member

Registered: 03/26/06
Posts: 310
Loc: Sydney, Australia
G'day Sam,

You are absolutely right but mere members cannot move posts. Perhaps the original post should have been copied and the reply posted in a new thread. I don't agree with you about the "Not quite" bit though. Speculation some of this is, but exactly why mammoths ended up they way they did really is something that may well explain some of the mechanisms of flips between glaciatons and interglacial periods.

Of course now your post and this one are also off topic. Sigh. But then again the topic started with a news article and was not all that much about science the science of Climate even in the first place.

Regards


Richard
_________________________
Sane=fits in. Unreasonable=world needs to fit to him. All Progress requires unreasonableness

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#16800 - 10/28/06 08:22 PM Re: Ocean array acts as climate alert
samwik Offline
Megastar

Registered: 10/10/06
Posts: 1164
Loc: Colorado
"You are absolutely right but mere members cannot move posts." -RicS
That's what I meant by changing the structure of the fora.

I'd also like to see a link to the "All Fora Overview" (Science a GoGo Forums) in that "Hop To" button on the bottom of each screen.

Thanks,
~samwik

P.S. ...watch out for the fora & fauna smile
_________________________
Pyrolysis creates reduced carbon! ...Time for the next step in our evolutionary symbiosis with fire.

Top
#16839 - 10/26/06 10:47 PM Re: Ocean array acts as climate alert
RicS Offline
Senior Member

Registered: 03/26/06
Posts: 310
Loc: Sydney, Australia
G'day Sam,

Hey, I've had an impact!

I have no problem with such studies. Ocean circulation is important to the understanding of our planet. Not all science has to be immediately of economic benefit (although I wonder about studies that include such things as mobile phone use and fertility - see other current thread).

I actually think my post was being written while yours ended up being posted and so your predictions were not far off at all. Is that a good thing or a bad thing?


Richard
_________________________
Sane=fits in. Unreasonable=world needs to fit to him. All Progress requires unreasonableness

Top
#16840 - 10/26/06 11:39 PM Re: Ocean array acts as climate alert
DA Morgan Offline
Megastar

Registered: 10/17/04
Posts: 4136
Loc: Seattle, WA
We can compare current salinity with that at past times by taking core samples. And at those same points in time we can determine, with some degree of accuracy, the climate.

Some assumptions must be made.

And with time they will be modified and become increasingly more accurate.

What Europe is worried about is the mid-Atlantic conveyor stopping. If it does Europe, as we know it ends for the rest of the lifetimes of all alive. Not a happy thought.

We know how to stop it. We don't have a clue how to restart it.
_________________________
DA Morgan

Top
#16841 - 10/27/06 10:54 AM Re: Ocean array acts as climate alert
RicS Offline
Senior Member

Registered: 03/26/06
Posts: 310
Loc: Sydney, Australia
G'day Dan,

It isn't all that easy to stop. It took a huge amount of fresh water to stop it for quite a limited period about 8,000 years ago and even then it seems that it was working again in about eight months. But it did have an impact on Europe for a while. I personally would not want to have been one of the tribes people that had gone to the trouble of having made summer clothes only to find we were stuck with basically very cold conditions for another century or so.

I don't think you can easily compare the records now being gathererd with pretty much anything. They can be compared with each successive year in the future if they keep it going long enough and I hope they do but core samples provide only limited information (and I'm a little confused here - sediment core samples or ice core samples - neither seems to be a good fit for temperature and salinity of the Atlantic in the area of the current recording over the last 100 years).

If the inter-ocean conveyor were to falter then I'd guess we'd have a reglaciation throughout the Northern Hemisphere. I'd be more worried if I lived in Canada or the US than Europe. The conditions in Europe, to some extent and set up to cope with snow and cold but that is not true for much of the US. I'm not sure you could get the conveyor to change in such a way that it stopped warming Europe but continued to work for the rest of the world and heat exchange is necessary somehow so I can't see it stopping. It does not stop during a glaciation or even during a reglaciation so it does not seem to be the trigger for a reglaciation. And I can't see how it could possibly work to cause a deglaciation.

The whole process smacks of "The Day After Tomorrow" and the science was a bit suspect in that movie. It made a good science fiction movie, emphasis on fiction. There is an explanation for the grass chewing woolly mammoth and the sudden extreme freezing that there does seem to be evidence for during the instability going into a reglaciation. It seems that jet streams are not only latitudinally unstable but can be altitudinally unstable during reglaciations. If a jet stream dipped to the point where it touched or gets very close to land, you get very fast air movement with incredibly cold air. Snap freeze! It seems that a jet stream, if it dipped towards the land would do so in the warmest area. That would be a lake. Thus you could get a jet stream ripping off the frozen skin of a lake, vacuuming up a large quantity of water into fine droplets, freezing these in the air and building up a block of ice that would snap freeze anything in its path.

While the hurricane in the South Atlantic is called a cold hurricane it does not act like a hurricane in several vital areas. It certainly does not produce the sinking of super cold air in its centre like they showed in the movie.

I'd be interested if you could explain what you meant by core samples, Dan. Personally I cannot see how they would determine climate in comparison to what this discussion is about. And using sediments or ice cores to determine world climate is a whole other topic.


Regards


Richard
_________________________
Sane=fits in. Unreasonable=world needs to fit to him. All Progress requires unreasonableness

Top
#16842 - 10/27/06 07:15 PM Re: Ocean array acts as climate alert
DA Morgan Offline
Megastar

Registered: 10/17/04
Posts: 4136
Loc: Seattle, WA
RicS wrote:
"It isn't all that easy to stop. It took a huge amount of fresh water to stop it for quite a limited period about 8,000 years ago"

Compare what it took to stop it the last time to the freshwater melt from Greenland.

Post the results and the sources here for everyone to examine.
_________________________
DA Morgan

Top
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