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Author Topic:   Global Warming
truthlover
Member (Idle past 4059 days)
Posts: 1548
From: Selmer, TN
Joined: 02-12-2003


Message 1 of 115 (371512)
12-21-2006 10:54 PM


Maybe this has been done before. I wouldn't have been too interested, because I didn't know much. However, recently I came across two completely opposed views through the media, and I had to do some research to find out who's lying to me (or passing on their own deception to me).
This seems a great place to test out what I'm finding.
The EPA's web site says that the following things are known about global warming (wording condensed by me):
1. Human activities have increased CO2 levels in the atmosphere.
2. A warming trend of roughly 1 degree fahrenheit occured during the 20th century.
3. Greenhouse gases like CO2 stay in the atmosphere, so they'll continue to accumulate.
4. Increasing greenhouse gases tend to warm the planet.
Not very specific, really. The more moderate anti-global warming people like Richard Lindzen (moderate as compared to say, Rush Limbaugh) could agree with all this. I agree with all this.
However, here's some specific things I think I'm finding. I've researched only the Antarctic Ice Sheet, the Greenland Ice Sheet, and sea levels (and Mt. Kilimanjaro specifically):
1. Only melting land ice raises sea level. Melting sea ice does not.
2. There are really three major land ice sheets talked about in the web sites I've looked at: The Greenland Ice Sheet, the West Antarctic Ice Sheet, and the East Antarctic Ice Sheet.
3. The Greenland Ice Sheet is not losing any mass, so it is not contributing to rising sea levels, despite all the hype about it. (From the EPA.) This isn't certain because of difficulties of measurement, but every study since 1968 listed on their site says it's the same or increasing.
4. The West Antarctic ice sheet is losing mass (NASA news release, March 2, 2006 and a Science Daily news release). This was only enough to raise global sea level about 0.2 or 0.4 mm/yr, about half the thickness of a sheet of paper or less.
5. The East Antarctic ice sheet is apparently gaining mass (Nature's web site news release).
6. The Antarctic Peninsula, which is a small part of West Antarctica, has increased in temperature by 4 or 5 degrees fahrenheit since 1947. This has caused much or perhaps almost all of the West Antarctic melting. NASA felt free to say that this temperature increase has no apparent link to global warming, but is localized, and "the jury is still out" as to whether the melting will continue.
7. The East Antarctic ice sheet contains 76.5% of the world's ice (85% of Antarctica's, which is 90% of the world's - from the Gulf of Maine link in point 8 and the Nature link in 5).
8. The highest prediction of global sea level increase I saw that looked remotely scholarly was 1 meter, attributed to "some scientists" by the Gulf of Maine Research Institute here. They add that "some scientists" say that warming could result in more snow in the Antarctic and thus reduce sea levels. Finally, they say that "most scientists" caution that it is very hard to predict what will happen.
My conclusion from what I've seen.
Greenhouse gas accumulation is very real. It causes global warming. How much is uncertain. What its effects have been to date is uncertain. Prediction of future effects is difficult.
The doomsayers, however, are wrong about some things.
1. Sea levels will not rise 15 to 20 feet in the near future, nor in this century.
2. The antarctic has lost a relatively small amount of mass, and the major part of Antarctica is gaining mass.
3. Greenland's ice sheet, the only other major ice sheet in the world, does not appear to be losing any mass.
I think that's nothing but an honest look at the data, but then, I'm not a scientist.
You are welcome to talk about other points, but these are the ones I'm checking on.

Replies to this message:
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 Message 5 by NosyNed, posted 12-22-2006 12:02 AM truthlover has not replied
 Message 12 by AnswersInGenitals, posted 01-11-2007 6:37 PM truthlover has not replied

  
AdminNosy
Administrator
Posts: 4754
From: Vancouver, BC, Canada
Joined: 11-11-2003


Message 2 of 115 (371513)
12-21-2006 11:04 PM


Thread moved here from the Proposed New Topics forum.

  
NosyNed
Member
Posts: 8996
From: Canada
Joined: 04-04-2003


Message 3 of 115 (371522)
12-21-2006 11:19 PM
Reply to: Message 1 by truthlover
12-21-2006 10:54 PM


Don't jump to conclusions so quickly
A few points:
1. Only melting land ice raises sea level. Melting sea ice does not.
2. There are really three major land ice sheets talked about in the web sites I've looked at: The Greenland Ice Sheet, the West Antarctic Ice Sheet, and the East Antarctic Ice Sheet.
These are simply true you may as well move them up with the other uncontentious items.
ABE (hit the button too soon)
3.. The Greenland Ice Sheet is not losing any mass, so it is not contributing to rising sea levels, despite all the hype about it. (From the EPA.) This isn't certain because of difficulties of measurement, but every study since 1968 listed on their site says it's the same or increasing.
I can't read the data clearly but the second chart give this summary line:
quote:
1843 76d 2246 86d 540 218 10 10e 2072 304
First 2 numbers being accumlation (over ground and all accumultion)
Next 3 numbers are melting, runoff and iceberg production
The last 3 are greater than the second so I don't know what it means.
5.The East Antarctic ice sheet is apparently gaining mass (Nature's web site news release).
That source says:
quote:
The thickening of the eastern ice sheet should not be seen as a long-term protection against a rise in sea level, warns Vaughan. Glaciers in West Antarctica are accelerating, releasing more and more icebergs into the sea. And the Antarctic Peninsula, which stretches towards South America, now regularly hits temperatures above 0 C in the summer, leading to direct melting of the ice there.
What's more, snowfall over East Antarctica will not continue to increase indefinitely in a warming world, Vaughan adds. Conversely, every extra degree of temperature rise will continue to accelerate glaciers and cause more melting on the western side of Antarctica, swelling the world's oceans further.
In addition the measurements are not complete it seems.
6
6. The Antarctic Peninsula, which is a small part of West Antarctica, has increased in temperature by 4 or 5 degrees fahrenheit since 1947. This has caused much or perhaps almost all of the West Antarctic melting. NASA felt free to say that this temperature increase has no apparent link to global warming, but is localized, and "the jury is still out" as to whether the melting will continue..
The jury is still out is the correct answer to this. Not that we can come down on one side or the other yet.
Your point 8 enforces that; we don't know.
To go from a small amount of information on complex processes to thinking we have the answer isn't a good idea.
I'd agree that current data does NOT support a 15 or 20 foot sea level raise in the next few decades but it is NOT ruled out either. There are positive feedback loops that could cause runaway change.
But we know that continued CO2 increases can warm things up even more. It is not impossible to cause a 20 foot sea level raise in decades and much, much more in a century.
So what is the best course of action when faced with such uncertainty?
What is the cost of even a 5 foot raise happening? How much risk is it prudent to take? What will we pay for "insurance"?
Edited by NosyNed, : to finish the reply

This message is a reply to:
 Message 1 by truthlover, posted 12-21-2006 10:54 PM truthlover has replied

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Omnivorous
Member
Posts: 3978
From: Adirondackia
Joined: 07-21-2005
Member Rating: 7.3


Message 4 of 115 (371523)
12-21-2006 11:21 PM
Reply to: Message 1 by truthlover
12-21-2006 10:54 PM


Before we start, I have one question:
Why are you (apparently) considering the Bush EPA (the Environmental Predation Advocates) an authoritative source? This is like discussing religion with someone who considers the Bible an infallible proof: what's the point?
Well before you reach your conclusions about the "doomsayers," you already seem to display a bias in your selection of authorities. Did you even look for other perspectives?
Okay, that's more than one question. Here's another:
Greenland is stable?
Google "Greenland melting."

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This message is a reply to:
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NosyNed
Member
Posts: 8996
From: Canada
Joined: 04-04-2003


Message 5 of 115 (371525)
12-22-2006 12:02 AM
Reply to: Message 1 by truthlover
12-21-2006 10:54 PM


From Science
Just a moment...
Glaciologists nailed down an unsettling observation this year: The world's two great ice sheets--covering Greenland and Antarctica--are indeed losing ice to the oceans, and losing it at an accelerating pace. Researchers don't understand why the massive ice sheets are proving so sensitive to an as-yet-modest warming of air and ocean water. The future of the ice sheets is still rife with uncertainty, but if the unexpectedly rapid shrinkage continues, low-lying coasts around the world--including New Orleans, South Florida, and much of Bangladesh--could face inundation within a couple of centuries rather than millennia.
and
Current ice sheet losses aren't raising sea level faster than 0.1 meter per century, but researchers fear that the rate could rise to a meter per century or more in the near future. As recently as 5 years ago, they assumed that global warming would simply melt more and more ice from the ice sheets, as it is melting mountain glaciers. But it turns out the ice isn't just melting faster, it is moving faster. Radar mapping shows that in recent years, glaciers carrying ice away from the sheets have sped up by as much as 100%. In West Antarctica, warming ocean waters seem to have attacked the floating tongues of ice that hold back the ice sheet's outlet glaciers. Around southern Greenland, something else seems to be quickening the pace of outlet glaciers, perhaps lubrication by increasing amounts of surface meltwater seeping to a glacier's base.
Now glaciologists are wondering how the next chapter will play out. Will the relatively strong warming around the ice continue, or will it be weakened by natural variations of climate? Will the ice sheets adjust to the new warmth by eventually slowing their ice loss? And will more glaciers succumb to the spreading warmth? A few more breakthroughs are definitely in order.

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truthlover
Member (Idle past 4059 days)
Posts: 1548
From: Selmer, TN
Joined: 02-12-2003


Message 6 of 115 (371575)
12-22-2006 9:16 AM
Reply to: Message 4 by Omnivorous
12-21-2006 11:21 PM


Why are you (apparently) considering the Bush EPA (the Environmental Predation Advocates) an authoritative source? This is like discussing religion with someone who considers the Bible an infallible proof: what's the point?
I have no history with which to choose my authorities, so I had to do the best I could. I tried to avoid, in whatever way I could, using far left or far right sources. Global warming seems to be as much a political issue as an environmental one (sadly).
I chose the EPA's climate change web site, because it just listed information, and I felt okay with it, because environmental web sites seemed to refer to it a lot. It's the anti-Sierra club type people who speak against the EPA's committee on climate change, not the environmentalists. The EPA's web site had links to the IPCC, which the right wingers seem to think is evil, so I figured all that was safe. If you can give me reasons not to, besides calling it a Bush EPA, I'd be glad to hear them.
Well before you reach your conclusions about the "doomsayers," you already seem to display a bias in your selection of authorities. Did you even look for other perspectives?
I don't think I displayed a bias. I think I chose the EPA for the reasons above. I chose the Nature web site because they're the publishers of Nature. I chose Science Daily and that Maine Gulf Institute, because they seemed to use real figures that everyone was using, and I used NASA, because it was a government organization. Sorry, my experience on health issues (especially research on herbal issues) makes me more comfortable with government web sites than private ones, because on health issues, they are easily the most honest. They don't hide research.
Google "Greenland melting."
Okay. The first link produced a fisherman's opinion that one iceberg is smaller. The second produced a bunch of comments about what "scientists" say and a vague reference to "this week's Nature" that gave no specifics as to what they got from it. The first line in that article says "Greenland's massive ice sheet could BEGIN to melt this century."
There's a "could" and a "begin" in that sentence, which means despite all the rhetoric in the rest of the article, there's no statement that Greenland is melting currently.
Finally, the third one, from a college--I like those web sites, too, as long as they're giving the author and why the author is writing on the subject, which they often do--gives melt extent data.
That data is newer than what I'd been able to find, so that's good, and it shows a steady increase since 1980.
The fourth is BBC World News. While it's just a news story, it at least names the scientist and quotes him on pertinent subjects (it's amazing how rare that is). None of this is really quantified or tied to sea level rise.
Ah, here we go. That GRACE observatory from NASA is cool. Real numbers. What's funny is that they list 39 cubic miles as higher than all previously published estimates for melting, while this site says 57 cubic miles for 2002-2005, and that's also based on GRACE. Strange.
One more comment about bias
I specifically skipped all the anti-global warming, right wing sites. That means I mostly run into left-wing bias, not right-wing, and all bias is somewhat irritating to me. Take the following statement, from the web site I just linked:
"Although earlier evidence using other techniques appeared to show that the East Antarctica ice sheet was actually thickening, satellite data gathered by Isabella Velicogna and John Wahr at Boulder found that melting -- primarily from the West Antarctic Ice Sheet -- had turned at least 36 cubic miles of ice to fresh water each year from 2002 to 2005."
Using other techniques??? The only evidence I found for the thickening of the East Antarctic ice sheet was from GRACE, the very same technique. And this paragraph doesn't contradict that. It drops this hint that the data saying the East Antarctic ice sheet is thickening is flawed, then never actually gives any evidence it's flawed. And it does more than hint that it's using a different technique, it actually says so, and it's not true.
I have to spend a lot of my time dodging those kind of intellectual land mines, and I don't have a history in science to help me do that. I just have to stay on my toes as I read.
That all said, it appears Greenland's ice sheet is melting at roughly the speed West Antarctica's is, and it's increased from 2002-2005.
Reasonable estimates of future sea level rise still seem to be at 1 meter max in a century, even from those sites I just looked at.

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truthlover
Member (Idle past 4059 days)
Posts: 1548
From: Selmer, TN
Joined: 02-12-2003


Message 7 of 115 (371577)
12-22-2006 9:28 AM
Reply to: Message 3 by NosyNed
12-21-2006 11:19 PM


Re: Don't jump to conclusions so quickly
First 2 numbers being accumlation (over ground and all accumultion)
Next 3 numbers are melting, runoff and iceberg production
The last 3 are greater than the second so I don't know what it means.
It means there's a net loss, but that table you were quoting (the second table on my link) was about Antarctica. It's older data, too, and so it's error margins were huge, bigger than the net loss. (There was a page explaining the tables that I didn't link to, sorry.)
We have GRACE data, too, which seems to be winning for reliability. That's all new since 2005, though.
Let me also address your post 5:
Current ice sheet losses aren't raising sea level faster than 0.1 meter per century, but researchers fear that the rate could rise to a meter per century or more in the near future.
This seems to be the real potential danger amount. 1 meter per century. That would be about 5 or 6 times what it was the last century.
In West Antarctica, warming ocean waters seem to have attacked the floating tongues of ice that hold back the ice sheet's outlet glaciers.
This was one of the more interesting things I found. Apparently, scientists were surprised to find that the ocean waters around West Antarctica had warmed by around 1 degree, uh, Fahrenheit, I think, since 1947. (I don't know why they were surprised. The report just said that climate models said the waters should be cooler.) This apparently must be the major contributor the breakup of the Ross Ice Shelf, because despite Antarctic Peninsula temperature increases, the Ross Ice Shelf air temperatures have actually been cooler.

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Fosdick 
Suspended Member (Idle past 5499 days)
Posts: 1793
From: Upper Slobovia
Joined: 12-11-2006


Message 8 of 115 (376259)
01-11-2007 4:04 PM


Biblical Prophesy vs. Global Warming

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Vacate
Member (Idle past 4600 days)
Posts: 565
Joined: 10-01-2006


Message 9 of 115 (376265)
01-11-2007 4:27 PM
Reply to: Message 8 by Fosdick
01-11-2007 4:04 PM


Re: Biblical Prophesy vs. Global Warming
From the Article writes:
“An Inconvenient Truth” can’t be shown unless Murphy is satisfied an opposing view also will be explained.
What is the opposing view? The article didn't report it. I would be interested to know what findings there are that "oppose" the video. I watched it and found it did a good job of showing what is happening and what it may lead to.
If the school board did allow students to watch "an Inconvenient Truth", what exacly would they tell the students is the opposing viewpoint? Is biblical prophecy in fact what they claim is the opposition, and if so what does it have to say about carbon dioxide and its effects? Anyone have some insight?

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subbie
Member (Idle past 1254 days)
Posts: 3509
Joined: 02-26-2006


Message 10 of 115 (376283)
01-11-2007 5:19 PM


Another viewpoint
Friends of Science, a Canadian based group, presents this graph which shows a closer correlation between rising temperatures and sunspots than CO2.
I'm not particularly interested in hearing about whether this group is one that does junk science or other ad hominem attacks on the group. Are the facts in the graph accurate? Can the obvious implications of the information be undermined by other facts or analyses?
Is it more likely that there is a sunspot connection than CO2?
If CO2 is responsible, why does the "temperature anomaly" precede the CO2 increase?
Edited by subbie, : No reason given.

Those who would sacrifice an essential liberty for a temporary security will lose both, and deserve neither. -- Benjamin Franklin
We see monsters where science shows us windmills. -- Phat

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crashfrog
Member (Idle past 1466 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 11 of 115 (376306)
01-11-2007 6:29 PM
Reply to: Message 10 by subbie
01-11-2007 5:19 PM


Re: Another viewpoint
Are the facts in the graph accurate?
Apparently not:
Page not found
quote:
However,close analysis of the central graphs
in all of these articles reveals questionable
handling of the underlying physical data.
In the 1991 article, the impressive agreement
of the solar curve with terrestrial temperatures
during the global warming of the recent decennia
had been a major factor in the article’s strong
impact. But this agreement was actually an
artifact: it had simply been obtained by adding,
to a heavily smoothed (“filtered”) curve, four
additional points covering the period of global
warming,which were only partially filtered or
not filtered at all.
The PDF provides a more accurate and longer-term graph comparing temperature to solar cycle; even the untrained eye can see that there's no relationship at all.

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 Message 10 by subbie, posted 01-11-2007 5:19 PM subbie has replied

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AnswersInGenitals
Member (Idle past 150 days)
Posts: 673
Joined: 07-20-2006


Message 12 of 115 (376308)
01-11-2007 6:37 PM
Reply to: Message 1 by truthlover
12-21-2006 10:54 PM


Ice sheet melting isn't the only cause of sea level rising. Water has an expansion coefficient of about 0.00023 per degree centigrade. Multiply that by the 3000 meter average ocean depth and you get about a 0.7 meter ocean level rise per degree C increase in temperature. Test problem for a science class: By how many degrees centigrade would the ocean temperatures have to increase for Jeb Bush to be governor of the smallest state in the union?
Also, your OP considers only sea level rising. You of course know that that is only one of many concerns about global warming, and is far from the most immediate or serious concerns.
The real issue with global warning is how do you make decisions in the face of uncertainty. (I've heard Intelligence defined as what you do next when you don't know what to do next.) If you think that there is only a low probability of your getting hit by a car when you cross the street, do you decide that it is a waste of your limit energy resources to look both ways when you cross that street? Apparently you do if you are a conservative. Don't we all wish that Bush had look both ways before crossing into Iraq?
Edited by AnswersInGenitals, : No reason given.

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subbie
Member (Idle past 1254 days)
Posts: 3509
Joined: 02-26-2006


Message 13 of 115 (376311)
01-11-2007 6:48 PM
Reply to: Message 11 by crashfrog
01-11-2007 6:29 PM


Re: Another viewpoint
Lacking the expertise to analyse the paper and determine whether the criticism is valid or not, I move to my second question.
How can CO2 be responsible for the "temperature anomaly" if the temperature rise began before the CO2 rise did?
At least one person thinks the causation may go in the other direction.

Those who would sacrifice an essential liberty for a temporary security will lose both, and deserve neither. -- Benjamin Franklin
We see monsters where science shows us windmills. -- Phat

This message is a reply to:
 Message 11 by crashfrog, posted 01-11-2007 6:29 PM crashfrog has replied

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Fosdick 
Suspended Member (Idle past 5499 days)
Posts: 1793
From: Upper Slobovia
Joined: 12-11-2006


Message 14 of 115 (376327)
01-11-2007 7:59 PM
Reply to: Message 13 by subbie
01-11-2007 6:48 PM


Re: Another viewpoint
subble wrote:
How can CO2 be responsible for the "temperature anomaly" if the temperature rise began before the CO2 rise did?
At least one person thinks the causation may go in the other direction.
Yes, I think what Robert Essenhigh is saying in the link”GLOBAL WARMING NATURAL, MAY END WITHIN 20 YEARS”should be carefully considered. For one thing, there are plenty of geologists who are suspicious that such a warming cycle might be the vanguard of another glaciation.
But local air pollution from carbon combustion is enough of a reason, for me at least, to try to clean up the atmosphere. Look at the progress made in LA”if catatlytic converters were not required LA air would not be fit to breathe. So of course there are immediate health benefits to cutting carbon dioxide emissions.
”Hoot Mon

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fallacycop
Member (Idle past 5520 days)
Posts: 692
From: Fortaleza-CE Brazil
Joined: 02-18-2006


Message 15 of 115 (376338)
01-11-2007 9:00 PM
Reply to: Message 12 by AnswersInGenitals
01-11-2007 6:37 PM


Ice sheet melting isn't the only cause of sea level rising. Water has an expansion coefficient of about 0.00023 per degree centigrade. Multiply that by the 3000 meter average ocean depth and you get about a 0.7 meter ocean level rise per degree C increase in temperature
Usually I enjoy your posts for how precisely correct they are.
This is one case, though, where I think you may have oversimplifyed
Water`s thermal expansion coefficient is actually quite variable as a function of temperature being zero at a temperature around 4 degrees Celsius, and the Oceans temperature varies quite a lot with depth.
try here No webpage found at provided URL: http://www.newton.dep.anl.gov/askasci/chem03/chem03335.htm
and here IIS 7.5 Detailed Error - 404.0 - Not Found
Besides, The temperature change of the air could take a very long time indeed to be reflected as a temperature change of the ocean due to water`s high specific heat. 3000 meters of water is a lot of water to heat.
To top it off, the ocean is heated from above, which means that we would have to wait the natural cycling of the ocean`s water in order to have it all heated up. This cycle takes several thousand years.

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