"Joseph Gwinn" wrote in message
...
In article ,
"Ed Huntress" wrote:

"Joseph Gwinn" wrote in message
...
In article ,
"Ed Huntress" wrote:

[snip]

You're talking about one measurement path, a Great Circle, which may
or
may
not cross numerous currents, the initiation site for El Nino, and so
on.
From that you're trying to draw a conclusion about global warming. You
don't
know if the pattern between here and NZ is pro-cyclical or
counter-cyclical
to the earth's temperature as a whole. You are talking about a
measurement
taken over a short span of years, while the data being looked at by
serious
scientists is data from decades at least, and hundreds of years in
some
cases.

Well, I don't have a dog in the debate from which this is taken, but I
will add
that it is not impossible to disentangle all those things. What is
done
is the acoustic equivalent of computerized tomography.

Here is a random article dredged up by google:
http://jjap.ipap.jp/link?JJAP/40/5446/.

Joe Gwinn

Joe, I'm going to skip the article, because there are 2,000 or 3,000 that
I'd have to read first.

Not if the intent is to understand the method.

Hey, Joe, I got curious and took a look at it. What in the hell are you
talking about here? Of COURSE temperature differentials result in sound
velocity differentials. That wasn't the question. Nor are statistical
sampling methods part of the question.

The question is, what is the effect of all of the variables upon ocean
temperature, current temperatures and paths, and their cyclical or
countercyclical relation to worldwide global warming? What's causing warming
or cooling along that linear path, and how does it relate to the overall
effect?

The article doesn't touch upon that. What it DOES do is explain a method for
measuring temperature with the velocity proxy. They've been able to do that
for 100 years, by my guess. This is just a quick and simple method, as the
article's title describes.

--
Ed Huntress

In article ,
"Ed Huntress" wrote:

"Joseph Gwinn" wrote in message
...
In article ,
"Ed Huntress" wrote:

"Joseph Gwinn" wrote in message
...
In article ,
"Ed Huntress" wrote:

[snip]

You're talking about one measurement path, a Great Circle, which may
or
may
not cross numerous currents, the initiation site for El Nino, and so
on.
From that you're trying to draw a conclusion about global warming. You
don't
know if the pattern between here and NZ is pro-cyclical or
counter-cyclical
to the earth's temperature as a whole. You are talking about a
measurement
taken over a short span of years, while the data being looked at by
serious
scientists is data from decades at least, and hundreds of years in
some
cases.

Well, I don't have a dog in the debate from which this is taken, but I
will add
that it is not impossible to disentangle all those things. What is
done
is the acoustic equivalent of computerized tomography.

Here is a random article dredged up by google:
http://jjap.ipap.jp/link?JJAP/40/5446/.

Joe Gwinn

Joe, I'm going to skip the article, because there are 2,000 or 3,000 that
I'd have to read first.

Not if the intent is to understand the method.

Hey, Joe, I got curious and took a look at it. What in the hell are you
talking about here? Of COURSE temperature differentials result in sound
velocity differentials. That wasn't the question. Nor are statistical
sampling methods part of the question.

Nor was it the point.


The question is, what is the effect of all of the variables upon ocean
temperature, current temperatures and paths, and their cyclical or
countercyclical relation to worldwide global warming? What's causing warming
or cooling along that linear path, and how does it relate to the overall
effect?

As I said, this allows one to measure the changes. Explaining them is quite
another matter.


The article doesn't touch upon that. What it DOES do is explain a method for
measuring temperature with the velocity proxy. They've been able to do that
for 100 years, by my guess. This is just a quick and simple method, as the
article's title describes.

I don't think they knew of this method 100 years ago, but it doesn't matter, as
the method is quite impractical without computers. Now it's easy.


Joe Gwinn

In article ,
"Ed Huntress" wrote:

"Joseph Gwinn" wrote in message
...
In article ,
"Ed Huntress" wrote:

"Joseph Gwinn" wrote in message
...
In article ,
"Ed Huntress" wrote:

[snip]

You're talking about one measurement path, a Great Circle, which may
or
may
not cross numerous currents, the initiation site for El Nino, and so
on.
From that you're trying to draw a conclusion about global warming. You
don't
know if the pattern between here and NZ is pro-cyclical or
counter-cyclical
to the earth's temperature as a whole. You are talking about a
measurement
taken over a short span of years, while the data being looked at by
serious
scientists is data from decades at least, and hundreds of years in
some
cases.

Well, I don't have a dog in the debate from which this is taken, but I
will add
that it is not impossible to disentangle all those things. What is
done
is the acoustic equivalent of computerized tomography.

Here is a random article dredged up by google:
http://jjap.ipap.jp/link?JJAP/40/5446/.

Joe Gwinn

Joe, I'm going to skip the article, because there are 2,000 or 3,000 that
I'd have to read first.

Not if the intent is to understand the method.

I'm interested in the conclusion. It's so easy to be misled by the methods.
Most of the pontificators here do exactly that.



One can "disentangle" the currents, but there is
still fundamental debate about the influences that initiate the El Ninos,
for example. So you can separate some effects but now you will have
experts
arguing over the causes -- and reading one article or two or a hundred
won't
tell you the full story behind those causes.

Well, it *is* an active research topic for sure, but they are figuring it
out.
And this is their tool. My point was that such a tool does exist.


For us non-experts, it's like searching for the golden fleece.

So, there is no reason to believe either side, and therefore no reason to
believe or to do anything at all? That's the obvious conclusion, because
the alternative is to choose on faith alone which of the warring groups to
believe.

Joe Gwinn

As Ranger and others have pointed out, the best use of our abilities on
impossibly complex topics like this is to use the usual tools we have for
judging which experts appear to know what they're talking about, and are
honest and sane.

It's like understanding cancer research. I wouldn't even try it. But I have
reason to believe the experts who speak through certain institutions. It
doesn't mean they're necessarily right, but experience shows that they're
the most likely to be so.

Anything else is self-delusion.

Cancer research isn't nearly as politicized as climate research, if only because
cancer research findings do not lead to proposals with such immense impacts.

Arguments of the form "most scientists believe ..." don't really have a very
good track record in science, which is neither a democracy nor a popularity
contest.

The classic example is Wegner and continental drift:
http://en.wikipedia.org/wiki/Continental_drift.

More recently, Pruisner and prions: http://en.wikipedia.org/wiki/Prion.
Pruisner was awarded a Nobel prize precisely for bucking the mainstream wisdom
of the day.

But anyway, you have convinced me that we have no hope of figuring out who to
believe, and so are better off simply biding out time. It will all sort itself
out presently.

Joe Gwinn

"Joseph Gwinn" wrote in message
...
In article ,
"Ed Huntress" wrote:

"Joseph Gwinn" wrote in message
...
In article ,
"Ed Huntress" wrote:

"Joseph Gwinn" wrote in message
...
In article ,
"Ed Huntress" wrote:

[snip]

You're talking about one measurement path, a Great Circle, which
may
or
may
not cross numerous currents, the initiation site for El Nino, and
so
on.
From that you're trying to draw a conclusion about global warming.
You
don't
know if the pattern between here and NZ is pro-cyclical or
counter-cyclical
to the earth's temperature as a whole. You are talking about a
measurement
taken over a short span of years, while the data being looked at by
serious
scientists is data from decades at least, and hundreds of years in
some
cases.

Well, I don't have a dog in the debate from which this is taken, but
I
will add
that it is not impossible to disentangle all those things. What is
done
is the acoustic equivalent of computerized tomography.

Here is a random article dredged up by google:
http://jjap.ipap.jp/link?JJAP/40/5446/.

Joe Gwinn

Joe, I'm going to skip the article, because there are 2,000 or 3,000
that
I'd have to read first.

Not if the intent is to understand the method.

Hey, Joe, I got curious and took a look at it. What in the hell are you
talking about here? Of COURSE temperature differentials result in sound
velocity differentials. That wasn't the question. Nor are statistical
sampling methods part of the question.

Nor was it the point.


The question is, what is the effect of all of the variables upon ocean
temperature, current temperatures and paths, and their cyclical or
countercyclical relation to worldwide global warming? What's causing
warming
or cooling along that linear path, and how does it relate to the overall
effect?

As I said, this allows one to measure the changes. Explaining them is
quite
another matter.

Well, we know that there are methods to measure the changes in ocean
temperature. There is only one significant question here, which is what does
it really tell us about overall warming? Dan's original point was that if
the guy he knows who is doing this work tells him there is global warming,
he'll believe it. To which my response is, I can't see how.



The article doesn't touch upon that. What it DOES do is explain a method
for
measuring temperature with the velocity proxy. They've been able to do
that
for 100 years, by my guess. This is just a quick and simple method, as
the
article's title describes.

I don't think they knew of this method 100 years ago, but it doesn't
matter, as
the method is quite impractical without computers. Now it's easy.

Well, they probably knew about velocities of sound in water in relation to
the water's temperature. Maybe they could measure it in the lab. What Dan is
talking about is measuring it across oceans. It may well be possible to a
high degree of accuracy. And it very well may tell you all kinds of useful
things about the relationships of ocean temperatures in certain regions to
weather. It probably also will tell you about a *mean* temperature trend
along a specific Great Circle line.

But the time span is too short to address the kinds of temperature trends
that are significant to the questions about global warming, and, as we've
now discussed ad nauseum, it doesn't address whether temperatures along that
particular line are in direct, or inverse relation to trends at the largest
scale.

Ocean currents change their paths with changes in climate. We may be seeing
it now with the Gulf Stream; it's moved within our lifetimes, as any old
offshore fisherman can confirm. And that's only one of the variables.

--
Ed Huntress

On 3/21/2010 10:44 AM, Joseph Gwinn wrote:
In ,
"Ed wrote:

"Joseph wrote in message
...
In ,
"Ed wrote:

[snip]

You're talking about one measurement path, a Great Circle, which may or
may
not cross numerous currents, the initiation site for El Nino, and so on.
From that you're trying to draw a conclusion about global warming. You
don't
know if the pattern between here and NZ is pro-cyclical or
counter-cyclical
to the earth's temperature as a whole. You are talking about a
measurement
taken over a short span of years, while the data being looked at by
serious
scientists is data from decades at least, and hundreds of years in some
cases.

Well, I don't have a dog in the debate from which this is taken, but I will add
that it is not impossible to disentangle all those things. What is done
is the acoustic equivalent of computerized tomography.

Here is a random article dredged up by google:
http://jjap.ipap.jp/link?JJAP/40/5446/.

Joe Gwinn

Joe, I'm going to skip the article, because there are 2,000 or 3,000 that
I'd have to read first.

Not if the intent is to understand the method.


One can "disentangle" the currents, but there is
still fundamental debate about the influences that initiate the El Ninos,
for example. So you can separate some effects but now you will have experts
arguing over the causes -- and reading one article or two or a hundred won't
tell you the full story behind those causes.

Well, it *is* an active research topic for sure, but they are figuring it out.
And this is their tool. My point was that such a tool does exist.


For us non-experts, it's like searching for the golden fleece.

So, there is no reason to believe either side, and therefore no reason to
believe or to do anything at all? That's the obvious conclusion, because the
alternative is to choose on faith alone which of the warring groups to believe.

Joe Gwinn


There are numerous ways to measure what is happening in the environment
and many of them are accurate. I don't know much about sound waves in
water but I have seen quite a bit of the research on ice and I think
that is one of the best measures of how much the planet is warming. Nova
on PBS just had a very good show called Extreme Ice where they gave a
lot of information on the state of glaciers and sheet ice. I think we
can agree that glaciers and sheet ice don't melt when the temperature
stays the same or gets colder. So it's only when the temperature rises
that you see ice melt. Columbia Glacier, Alaska's biggest is melting at
a very rapid clip. They set up lasers to measure how fast it's flowing
and it's moving fast. In fact, ice is melting all over the planet and
glaciers are shrinking. That's a fact. I don't see that happening unless
the planetary temperature is rising. So by the ice alone the evidence is
that warming is happening. Is man causing it is the question. There is
plenty of evidence that says that is the cause of it. Even if it's not
it's better to avoid something than to make an error and have to come
back and correct it. I think that is the prudent course to take when it
comes to global warming. I also expect that energy producers and
industrial businesses won't go along with that view.

Hawke

On Mar 21, 2:01*pm, "Ed Huntress" wrote:
"Joseph Gwinn" wrote in message

...





In article ,
"Ed Huntress" wrote:

"Joseph Gwinn" wrote in message
...
In article ,
"Ed Huntress" wrote:

[snip]

You're talking about one measurement path, a Great Circle, which may
or
may
not cross numerous currents, the initiation site for El Nino, and so
on.
From that you're trying to draw a conclusion about global warming. You
don't
know if the pattern between here and NZ is pro-cyclical or
counter-cyclical
to the earth's temperature as a whole. You are talking about a
measurement
taken over a short span of years, while the data being looked at by
serious
scientists is data from decades at least, and hundreds of years in
some
cases.

Well, I don't have a dog in the debate from which this is taken, but I
will add
that it is not impossible to disentangle all those things. *What is
done
is the acoustic equivalent of computerized tomography.

Here is a random article dredged up by google:
http://jjap.ipap.jp/link?JJAP/40/5446/.

Joe Gwinn

Joe, I'm going to skip the article, because there are 2,000 or 3,000 that
I'd have to read first.

Not if the intent is to understand the method.

I'm interested in the conclusion. It's so easy to be misled by the methods.
Most of the pontificators here do exactly that.







*One can "disentangle" the currents, but there is
still fundamental debate about the influences that initiate the El Ninos,
for example. So you can separate some effects but now you will have
experts
arguing over the causes -- and reading one article or two or a hundred
won't
tell you the full story behind those causes.

Well, it *is* an active research topic for sure, but they are figuring it
out.
And this is their tool. *My point was that such a tool does exist.

For us non-experts, it's like searching for the golden fleece.

So, there is no reason to believe either side, and therefore no reason to
believe or to do anything at all? *That's the obvious conclusion, because
the
alternative is to choose on faith alone which of the warring groups to
believe.

Joe Gwinn

As Ranger and others have pointed out, the best use of our abilities on
impossibly complex topics like this is to use the usual tools we have for
judging which experts appear to know what they're talking about, and are
honest and sane.

It's like understanding cancer research. I wouldn't even try it. But I have
reason to believe the experts who speak through certain institutions. It
doesn't mean they're necessarily right, but experience shows that they're
the most likely to be so.

Anything else is self-delusion.

--
Ed Huntress

And that doesn't mean choosing the scientists who are arriving at
conclusions that suit your political agenda. It means setting aside
your preconceived notions, and asking yourself whether the scientist's
work is believable. A large part of this judgement includes taking a
look at the company the scientist keeps - as Ed said, you'd be more
likely to believe scientist who speak through certain institutions.

For instance, I'd be more likely to put stock (on this subject) in a
scientist working for the Lamont-Doherty Earth Observatory than I
would put in a scientist from the Heritage Foundation.

On Mar 21, 5:10*pm, Joseph Gwinn wrote:

[snip]

Cancer research isn't nearly as politicized as climate research, if only because
cancer research findings do not lead to proposals with such immense impacts.

Really? Stem cells aren't politicized enough to rate a place in this
discussion?

[snip]

It's like understanding cancer research. I wouldn't even try it. But I have
reason to believe the experts who speak through certain institutions. It
doesn't mean they're necessarily right, but experience shows that they're
the most likely to be so.

Anything else is self-delusion.

--
Ed Huntress

And that doesn't mean choosing the scientists who are arriving at
conclusions that suit your political agenda. It means setting aside
your preconceived notions, and asking yourself whether the scientist's
work is believable. A large part of this judgement includes taking a
look at the company the scientist keeps - as Ed said, you'd be more
likely to believe scientist who speak through certain institutions.

For instance, I'd be more likely to put stock (on this subject) in a
scientist working for the Lamont-Doherty Earth Observatory than I
would put in a scientist from the Heritage Foundation.

You put your finger on the trouble right there. Whereas you would be
more likely to believe a scientist working for the Lamont-Doherty
Observatory a right winger would reject any scientist that didn't work
for the Heritage Foundation. And that explains why there is a dispute.
The deniers only believe the information coming from political outlets
that have no scientific credibility whatsoever. No wonder you wind up in
arguments with them.

Hawke

In article ,
"Ed Huntress" wrote:

"Joseph Gwinn" wrote in message
...
In article ,
"Ed Huntress" wrote:

"Joseph Gwinn" wrote in message
...
In article ,
"Ed Huntress" wrote:

"Joseph Gwinn" wrote in message
...
In article ,
"Ed Huntress" wrote:

[snip]

You're talking about one measurement path, a Great Circle, which
may
or
may
not cross numerous currents, the initiation site for El Nino, and
so
on.
From that you're trying to draw a conclusion about global warming.
You
don't
know if the pattern between here and NZ is pro-cyclical or
counter-cyclical
to the earth's temperature as a whole. You are talking about a
measurement
taken over a short span of years, while the data being looked at by
serious
scientists is data from decades at least, and hundreds of years in
some
cases.

Well, I don't have a dog in the debate from which this is taken, but
I
will add
that it is not impossible to disentangle all those things. What is
done
is the acoustic equivalent of computerized tomography.

Here is a random article dredged up by google:
http://jjap.ipap.jp/link?JJAP/40/5446/.

Joe Gwinn

Joe, I'm going to skip the article, because there are 2,000 or 3,000
that
I'd have to read first.

Not if the intent is to understand the method.

Hey, Joe, I got curious and took a look at it. What in the hell are you
talking about here? Of COURSE temperature differentials result in sound
velocity differentials. That wasn't the question. Nor are statistical
sampling methods part of the question.

Nor was it the point.


The question is, what is the effect of all of the variables upon ocean
temperature, current temperatures and paths, and their cyclical or
countercyclical relation to worldwide global warming? What's causing
warming
or cooling along that linear path, and how does it relate to the overall
effect?

As I said, this allows one to measure the changes. Explaining them is
quite
another matter.

Well, we know that there are methods to measure the changes in ocean
temperature. There is only one significant question here, which is what does
it really tell us about overall warming? Dan's original point was that if
the guy he knows who is doing this work tells him there is global warming,
he'll believe it. To which my response is, I can't see how.

I have not talked to Dan's friend, but I would guess that the friend is looking
to see if the average temperature of and/or total heat energy within the deep
ocean water mass has in fact increased, and if so by how much. This can be
accomplished by a direct measurement, without understanding why the temperature
changed.


The article doesn't touch upon that. What it DOES do is explain a method
for
measuring temperature with the velocity proxy. They've been able to do
that
for 100 years, by my guess. This is just a quick and simple method, as
the
article's title describes.

I don't think they knew of this method 100 years ago, but it doesn't
matter, as
the method is quite impractical without computers. Now it's easy.

Well, they probably knew about velocities of sound in water in relation to
the water's temperature. Maybe they could measure it in the lab.

Yes, they knew this 100 years ago.


What Dan is
talking about is measuring it across oceans. It may well be possible to a
high degree of accuracy. And it very well may tell you all kinds of useful
things about the relationships of ocean temperatures in certain regions to
weather. It probably also will tell you about a *mean* temperature trend
along a specific Great Circle line.

Measuring across oceans is precisely what is done. And, acoustic computerized
tomography gives you the voxel-by-voxel temperature of the ocean, not just the
mean temperature of a great-circle path.

The method resembles that used with X-rays (in CT scanners), where the X-ray
attenuation of a very large number of independent paths and directions is
combined mathematically to yield the 2D attenuation function (which we see as
the image).

Circling back to acoustics, what is measured is the transit times along a large
number of paths through the ocean of interest. These transit-time measurements
are combined to compute the speed of sound in each and every voxel, yielding the
speed image. From this (and independent salinity measurements) one can compute
temperature.


But the time span is too short to address the kinds of temperature trends
that are significant to the questions about global warming, and, as we've
now discussed ad nauseum, it doesn't address whether temperatures along that
particular line are in direct, or inverse relation to trends at the largest
scale.

Yes, but what's the point? Of course the Vikings didn't record such data.

But the data can help answer the question of how much thermal energy is stored
in the deep ocean, and how quickly it gets there. These are big issues in the
climate models, and measured data will help settle the arguments about which
approach is correct.


Ocean currents change their paths with changes in climate. We may be seeing
it now with the Gulf Stream; it's moved within our lifetimes, as any old
offshore fisherman can confirm. And that's only one of the variables.

True enough, but the intent is to measure heat storage in the deep ocean.


Joe Gwinn

On Mar 21, 5:16*pm, "Ed Huntress" wrote:

[snip of discussion of science stuff]

Well, we know that there are methods to measure the changes in ocean
temperature. There is only one significant question here, which is what does
it really tell us about overall warming? Dan's original point was that if
the guy he knows who is doing this work tells him there is global warming,
he'll believe it. To which my response is, I can't see how.


Ed, I think you have, intentionally or otherwise, hit the nail
squarely on the head. If Dan's friend were to tell him that he has
concluded through his scientific research that there is most certainly
global warming, I believe Dan would start looking for a new friend.

[snip of more science sounding stuff]

On Mon, 22 Mar 2010 09:20:59 -0400, Joseph Gwinn wrote:
In article ,
"Ed Huntress" wrote:

[...]

What Dan is talking about is measuring it across oceans. It may
well be possible to a high degree of accuracy. And it very well
may tell you all kinds of useful things about the relationships
of ocean temperatures in certain regions to weather. It probably
also will tell you about a *mean* temperature trend along a
specific Great Circle line.

Measuring across oceans is precisely what is done. And, acoustic
computerized tomography gives you the voxel-by-voxel temperature
of the ocean, not just the mean temperature of a great-circle path.

The method resembles that used with X-rays (in CT scanners), where
the X-ray attenuation of a very large number of independent paths
and directions is combined mathematically to yield the 2D
attenuation function (which we see as the image).

Circling back to acoustics, what is measured is the transit times
along a large number of paths through the ocean of interest.
These transit-time measurements are combined to compute the speed
of sound in each and every voxel, yielding the speed image. From
this (and independent salinity measurements) one can compute
temperature.

Not just salinity. From the Science Observer column of the
March-April 2010 issue of American Scientist, pp. 121-122:

Amplifying with Acid: More carbon dioxide in the atmosphere means a
noisier ocean

"...[CO2 absorption] also has a secondary consequence: it
decreases the ocean's ability to absorb low-frequency sound.

"Oceanographers Tatia Ilyna and Richard Zeebe at the University of
Hawaii, along with geochemist Peter Brewer of the Monterey Bay
Aquarium Research Institute in California, report in the December
20 issue of Nature Geoscience that lowering the pH of the ocean by
0.6 units could decrease underwater sound absorption by more than
60 percent."

"... Changes in pH can impact the deep ocean because at about 1
kilometer down, the properties of temperature and pressure combine
to produce a 'channel' of water in which sound can propagate for
may thousands of kilometers. Whales and other marine life make
use of this channel for long-range communication. Most human-made
noise forms at the surface, but it can reflect and refract down
into this channel as well. ..."


You may now return to your regularly-scheduled discussion, dialogue,
and/or debate. grin


Frank McKenney
--
Reading achievement will nor advance significantly until schools
recognize and act on the fact that it depends on the possession of
a broad but definable range of diverse knowledge. The effective
teaching of reading will require schools to teach the diverse,
enabling knowledge that reading requires.
-- E.D. Hirsch, Jr./The Knowledge Deficit
--
Frank McKenney, McKenney Associates
Richmond, Virginia / (804) 320-4887
Munged E-mail: frank uscore mckenney ayut mined spring dawt cahm (y'all)

"Joseph Gwinn" wrote in message
...
In article ,
"Ed Huntress" wrote:

"Joseph Gwinn" wrote in message
...
In article ,
"Ed Huntress" wrote:

"Joseph Gwinn" wrote in message
...
In article ,
"Ed Huntress" wrote:

[snip]

You're talking about one measurement path, a Great Circle, which
may
or
may
not cross numerous currents, the initiation site for El Nino, and
so
on.
From that you're trying to draw a conclusion about global warming.
You
don't
know if the pattern between here and NZ is pro-cyclical or
counter-cyclical
to the earth's temperature as a whole. You are talking about a
measurement
taken over a short span of years, while the data being looked at by
serious
scientists is data from decades at least, and hundreds of years in
some
cases.

Well, I don't have a dog in the debate from which this is taken, but
I
will add
that it is not impossible to disentangle all those things. What is
done
is the acoustic equivalent of computerized tomography.

Here is a random article dredged up by google:
http://jjap.ipap.jp/link?JJAP/40/5446/.

Joe Gwinn

Joe, I'm going to skip the article, because there are 2,000 or 3,000
that
I'd have to read first.

Not if the intent is to understand the method.

I'm interested in the conclusion. It's so easy to be misled by the
methods.
Most of the pontificators here do exactly that.



One can "disentangle" the currents, but there is
still fundamental debate about the influences that initiate the El
Ninos,
for example. So you can separate some effects but now you will have
experts
arguing over the causes -- and reading one article or two or a hundred
won't
tell you the full story behind those causes.

Well, it *is* an active research topic for sure, but they are figuring
it
out.
And this is their tool. My point was that such a tool does exist.


For us non-experts, it's like searching for the golden fleece.

So, there is no reason to believe either side, and therefore no reason
to
believe or to do anything at all? That's the obvious conclusion,
because
the alternative is to choose on faith alone which of the warring groups
to
believe.

Joe Gwinn

As Ranger and others have pointed out, the best use of our abilities on
impossibly complex topics like this is to use the usual tools we have for
judging which experts appear to know what they're talking about, and are
honest and sane.

It's like understanding cancer research. I wouldn't even try it. But I
have
reason to believe the experts who speak through certain institutions. It
doesn't mean they're necessarily right, but experience shows that they're
the most likely to be so.

Anything else is self-delusion.

Cancer research isn't nearly as politicized as climate research, if only
because
cancer research findings do not lead to proposals with such immense
impacts.

Well, that's certainly true. The cranks and contrarians in cancer research
don't get much of a hearing. In climatology, they get funded by coal and
power companies, publish best-selling books, and go on speaking tours.

The political overtones cut both ways. There's always a chance that the
contrarians are right. But the noise level gets so high, when there are
financial interests who have a big stake in promoting their ideas, that it
becomes even more important to size up the sources and judge their
sensibility and motivations, rather than to try to pretend we actually know
the scientific story. At best, we come off as half-assed pseudo-scientists
when we try.


Arguments of the form "most scientists believe ..." don't really have a
very
good track record in science, which is neither a democracy nor a
popularity
contest.

If you thought hard about examples, you'd probably realize how vacuous that
claim really is. What "most scientists believe" probably is right 90% of the
time. That's because the times they are right are unremarkable. It's those
much rarer times they are wrong that stick in our memories.


The classic example is Wegner and continental drift:
http://en.wikipedia.org/wiki/Continental_drift.

More recently, Pruisner and prions: http://en.wikipedia.org/wiki/Prion.
Pruisner was awarded a Nobel prize precisely for bucking the mainstream
wisdom
of the day.

But anyway, you have convinced me that we have no hope of figuring out who
to
believe, and so are better off simply biding out time. It will all sort
itself
out presently.

We have likelihoods based on our personal evaluations of the scientific
communities. We do not have certainty. To the extent that we have to support
one side or the other (which hardly is pressing upon most of us), we can
only judge their appearances and motivations.

--
Ed Huntress

In article ,
Frnak McKenney wrote:

On Mon, 22 Mar 2010 09:20:59 -0400, Joseph Gwinn wrote:
In article ,
"Ed Huntress" wrote:

[...]

What Dan is talking about is measuring it across oceans. It may
well be possible to a high degree of accuracy. And it very well
may tell you all kinds of useful things about the relationships
of ocean temperatures in certain regions to weather. It probably
also will tell you about a *mean* temperature trend along a
specific Great Circle line.

Measuring across oceans is precisely what is done. And, acoustic
computerized tomography gives you the voxel-by-voxel temperature
of the ocean, not just the mean temperature of a great-circle path.

The method resembles that used with X-rays (in CT scanners), where
the X-ray attenuation of a very large number of independent paths
and directions is combined mathematically to yield the 2D
attenuation function (which we see as the image).

Circling back to acoustics, what is measured is the transit times
along a large number of paths through the ocean of interest.
These transit-time measurements are combined to compute the speed
of sound in each and every voxel, yielding the speed image. From
this (and independent salinity measurements) one can compute
temperature.

Not just salinity. From the Science Observer column of the
March-April 2010 issue of American Scientist, pp. 121-122:

Amplifying with Acid: More carbon dioxide in the atmosphere means a
noisier ocean

"...[CO2 absorption] also has a secondary consequence: it
decreases the ocean's ability to absorb low-frequency sound.

"Oceanographers Tatia Ilyna and Richard Zeebe at the University of
Hawaii, along with geochemist Peter Brewer of the Monterey Bay
Aquarium Research Institute in California, report in the December
20 issue of Nature Geoscience that lowering the pH of the ocean by
0.6 units could decrease underwater sound absorption by more than
60 percent."

I read this too, but they don't claim a significant effect on the speed of
sound, only reduced sound attenuation, which actually makes speed measurements
easier.


"... Changes in pH can impact the deep ocean because at about 1
kilometer down, the properties of temperature and pressure combine
to produce a 'channel' of water in which sound can propagate for
many thousands of kilometers. Whales and other marine life make
use of this channel for long-range communication. Most human-made
noise forms at the surface, but it can reflect and refract down
into this channel as well. ..."

This channel is very effective, allowing communications across the entire
Pacific Ocean basin, for instance. This works because confining the sound to
spread in a 2D channel (versus 3D space) changes the inverse-square-of-distance
path attenuation law into a simple inverse-of-distance path attenuation law,
which makes huge difference at large distances.


You may now return to your regularly-scheduled discussion, dialogue,
and/or debate. grin

Yep.

Joe Gwinn

In article ,
"Ed Huntress" wrote:

"Joseph Gwinn" wrote in message
...
In article ,
"Ed Huntress" wrote:

"Joseph Gwinn" wrote in message
...
In article ,
"Ed Huntress" wrote:

"Joseph Gwinn" wrote in message
...
In article ,
"Ed Huntress" wrote:

[snip]

You're talking about one measurement path, a Great Circle, which
may
or
may
not cross numerous currents, the initiation site for El Nino, and
so
on.
From that you're trying to draw a conclusion about global warming.
You
don't
know if the pattern between here and NZ is pro-cyclical or
counter-cyclical
to the earth's temperature as a whole. You are talking about a
measurement
taken over a short span of years, while the data being looked at by
serious
scientists is data from decades at least, and hundreds of years in
some
cases.

Well, I don't have a dog in the debate from which this is taken, but
I
will add
that it is not impossible to disentangle all those things. What is
done
is the acoustic equivalent of computerized tomography.

Here is a random article dredged up by google:
http://jjap.ipap.jp/link?JJAP/40/5446/.

Joe Gwinn

Joe, I'm going to skip the article, because there are 2,000 or 3,000
that
I'd have to read first.

Not if the intent is to understand the method.

I'm interested in the conclusion. It's so easy to be misled by the
methods.
Most of the pontificators here do exactly that.



One can "disentangle" the currents, but there is
still fundamental debate about the influences that initiate the El
Ninos,
for example. So you can separate some effects but now you will have
experts
arguing over the causes -- and reading one article or two or a hundred
won't
tell you the full story behind those causes.

Well, it *is* an active research topic for sure, but they are figuring
it
out.
And this is their tool. My point was that such a tool does exist.


For us non-experts, it's like searching for the golden fleece.

So, there is no reason to believe either side, and therefore no reason
to
believe or to do anything at all? That's the obvious conclusion,
because
the alternative is to choose on faith alone which of the warring groups
to
believe.

Joe Gwinn

As Ranger and others have pointed out, the best use of our abilities on
impossibly complex topics like this is to use the usual tools we have for
judging which experts appear to know what they're talking about, and are
honest and sane.

It's like understanding cancer research. I wouldn't even try it. But I
have
reason to believe the experts who speak through certain institutions. It
doesn't mean they're necessarily right, but experience shows that they're
the most likely to be so.

Anything else is self-delusion.

Cancer research isn't nearly as politicized as climate research, if only
because
cancer research findings do not lead to proposals with such immense
impacts.

Well, that's certainly true. The cranks and contrarians in cancer research
don't get much of a hearing. In climatology, they get funded by coal and
power companies, publish best-selling books, and go on speaking tours.

The political overtones cut both ways. There's always a chance that the
contrarians are right. But the noise level gets so high, when there are
financial interests who have a big stake in promoting their ideas, that it
becomes even more important to size up the sources and judge their
sensibility and motivations, rather than to try to pretend we actually know
the scientific story. At best, we come off as half-assed pseudo-scientists
when we try.


Arguments of the form "most scientists believe ..." don't really have a
very good track record in science, which is neither a democracy nor a
popularity contest.

If you thought hard about examples, you'd probably realize how vacuous that
claim really is. What "most scientists believe" probably is right 90% of the
time. That's because the times they are right are unremarkable. It's those
much rarer times they are wrong that stick in our memories.

I didn't claim that majority opinion was wrong a high fraction of the time, only
that there are some really striking examples, and given that we are in an area
of heated debate coupled with enormous impact, caution is advised.

A good example supporting your point is Halton Arp, who argues that Quasars are
not associated with galaxies. http://en.wikipedia.org/wiki/Halton_Arp Halton
still publishes from time to time. The astronomy community listens but no
longer really agrees, but nobody tries to run him out of town on a rail either.

More broadly, in science it's the proof that ultimately counts, not the
popularity contest. Although it can be hard to tell in the heat of debate.


The classic example is Wegner and continental drift:
http://en.wikipedia.org/wiki/Continental_drift.

More recently, Pruisner and prions: http://en.wikipedia.org/wiki/Prion.
Pruisner was awarded a Nobel prize precisely for bucking the mainstream
wisdom of the day.

But anyway, you have convinced me that we have no hope of figuring out who
to believe, and so are better off simply biding out time. It will all sort
itself out presently.

We have likelihoods based on our personal evaluations of the scientific
communities. We do not have certainty. To the extent that we have to support
one side or the other (which hardly is pressing upon most of us), we can
only judge their appearances and motivations.

Also entering into the likelihood evaluations are the costs of the proposed
paths and the consequences of choosing the wrong alternative.

In the climate debate, given that we civilians have no hope of really
understanding the arguments pro and con, choosing which side to believe cannot
be based on science, leaving us with only faith and/or popularity.

One side loudly proclaims that we must spend immense sums and turn Civilization
upsidedown to prevent a harm whose existence, magnitude, timing, and mitigations
are all sharply questioned by the other side.

We have been down this road many times over history. The end of the world has
been predicted many many times. But life goes on ... and the actual disasters
are rarely the predicted disasters. What to do?

Temporize. Eventually one side or the other will manage to produce the evidence
needed to settle the debate. Or, more likely, the evidence will arrive in
increments, causing the debate to go sidewise, into areas not even thought of
today. So, temporize until the smoke clears.

Joe Gwinn