If this is global warming...
 

On Feb 17, 9:11 am, (Doug Miller) wrote:
In article .com, wrote:
On Feb 17, 12:40 am, (Doug Miller) wrote:
In article .com,
wrote:
On Feb 15, 8:23 am, (Doug Miller) wrote: 5) By what possible mechanism does human action on Earth cause the
recently observed shrinkage of thepolaricecapson ***MARS*** ?

That, alone, is more than enough to discount the entire notion that the
Earth
is warming due to human activity.

Why?

Because ifMarsis warming, it's pretty clearly due to increased solar
output;
if solar output has increased, that would explain warming here too -- in
fact,
it would make warming here pretty much unavoidable.

Or perhaps you're prepared to posit some mechanism by which human activity on
Earth causes global warming on other planets too?

The solar output as measured near the Earth has been decreasing
during the same period as when warming was observed onMars.

Source for that statement? I think that's incorrect.


Sure, in fact I did this several days ago but it appears the
posting failed. Are you, by any chance, an electrical or
electronics engineer?

First though, let's consider a little sense. Regardiing
Martian warming you wrote:

"That, alone, is more than enough to discount
the entire notion that the Earth is warming due
to human activity.
.... Because if Mars is warming, it's pretty clearly
due to increased solar output; if solar output has
increased, that would explain warming here too
-- in fact, it would make warming here pretty much
unavoidable."

To be confident in those statements you would have
to KNOW:

1) The solar constant is increasing.

and

2) NO other factors affect warming on either
the Earth or Mars.

Back to facts.

Have you heard of the eleven year solar cycle?

The last solar max was in 2000-2001, we are
now near solar minimum. It is over that same
period that Martian warming was observed.

http://www.sec.noaa.gov/SolarCycle/
http://www.pmodwrc.ch/pmod.php?topic.../SolarConstant
http://mars.jpl.nasa.gov/mgs/newsroom/20050920a.html
http://mars.jpl.nasa.gov/mgs/msss/ca...rel/index.html
http://books.nap.edu/openbook.php?re...11676&page=102
http://www.terradaily.com/reports/Ch...rming_999.html

The studies I have found put an upper limit of about
+0.1 W/sqm on any change in the solar constant over
the last 30 years which is calculated to have at most,
one quarter of the effect of the increased CO2 over the
same period.

Have you found anything that estimates it as
being higher? OH, I forgot for a minute, you
don't believe in citing sources.


Would you agree that the great Martian Dust Storm of 1971 was
not anthropogenic?

Of course. Would you agree that a dust storm that occurred 36 years ago is not
relevant to changes in Martian climate that are occurring now?

No. Dust storms are an important feature of the
Martian climate:

http://science.nasa.gov/headlines/y2001/ast16jul_1.htm

Long-term climate change is influenced by variation
in the alignment of the solstices, between the polar
axis of the planet and the semi-major axis of its orbit
and the orbital eccentricity.

For Mars, those effects are all
much larger than for the Earth, and obviously
quite independent. Mars also has a thinner atmos-
phere and lacks the Earth's oceans so it does not
benefit from the buffering effect of each.

These days here on the Earth the summer solstice is
near apohelion, which minimizes Northern Hemisphere
heating during the Northern Summer. Thus summer
in the Southern Hemisphere is shorter. IOW we
are in a period of minimal climate forcing due to
orbital considerations. I dunno about Mars.
Why don't you check and get back to us?


Or perhaps you're prepared to posit that the Earth andMarscan
have similar trends for entirely different reasons?

Or perhaps you're just a hypocrite who wants to have it both ways. Here's your
position, summed up in two sentences:

Earth gets warmer at the same time human industrial activity increases --
cause and effect.Marsgets warmer at the same time Earth does -- coincidence.


False.

OTOH, your approach appears to be based on
steadfastly avoiding any effort to educate yourself.

--

FF

If this is global warming...
 

On Mar 1, 6:11 pm, wrote:

...

These days here on the Earth the summer solstice is
near apohelion, which minimizes Northern Hemisphere
heating during the Northern Summer.

Sorry, minimal seasonal variation in insolation occurs when the
equinoxes, not the solstices, are coincident with apo- and
perihelion.

So we are near a maximum, not a minimum. The last maximum
was around the end of the last ice age and we've had one
minimum roughly halfway between then and now, demonstrating
that large scale variation of the Earth's climate are not caused
(at least not soley) by those effects.

--

FF

If this is global warming...
 

On Mar 2, 11:52 am, wrote:
On Mar 1, 6:11 pm, wrote:
...
So we are near a maximum, not a minimum. The last maximum
was around the end of the last ice age and we've had one
minimum roughly halfway between then and now, demonstrating
that large scale variation of the Earth's climate are not caused
(at least not soley) by those effects.


And, long-term climate change on the Earth is
driven by or at least heavily influenced by
long-term changes in eccentricity and obliquity.
That is over periods of time greater than the
precessional period:

http://www.livescience.com/forcesofn...arth_tilt.html
http://science.enotes.com/earth-scie...kovitch-cycles

Those are cyclical effects with periods of several tens
to a couple of hundred thousands of years.

The global warming being modeled based on the observed
change in CO2 concentration is a much shorter-term
phenomenon, over a period of a couple of hundred
years, superimposed on those long-term effects.

--

FF

If this is global warming...
 

On Feb 17, 3:00 am, wrote:
On Feb 17, 1:08 am, "Leon" wrote:

wrote in message

roups.com...

Earlier,Leonwrote:

"Since 1999 it [the Earth, FF] has been
cooling off and the ice at Antarctica has increased by
over 10% in the past few years. "

and I replied"

I'd like you to show some support for either statement.

Here are some photos showing a buttload of ice lost from Antarctica
in 2002:

http://www.npr.org/programs/atc/feat...ar/antarctica/

If there has been a gain since, it is doubtful that it has made up f
or what was lost.

...

Ok, you provided that support with your link.

And I pointed out that wasn't so, concluding:


Since the article does not quantify any gains at all in any part of
Antarctica, it certainly does not support your claim of a net gain.

No honest person reading and understanding the article would claim
that it does.


However, if I am reading the abstract of this paper correctly,
(Note it is in .pdf format)

http://www.igsoc.org/news/pressreleases/Zwally509.pdf

There was a net gain of ice in both Antarctica and Greenland
over the period of the study, 1992 - 2002. Averaged over that
ten year period the gain was 27 billion tons per year (Gt/a).

The net gain in Greenland was due to a gain in the interior
despite a loss at the margins. In Antarctica there was a net
loss on land net gain in sea ice.

I don't know if that data includes the March, 2002 collapse of
the Larsen B ice shelf, which was a loss of about 500 Gt.

I'll check with one of the authors to see.

I've also found a lot of information indicating net losses of ice
in the Arctic, and a net loss in the world's glaciers, but
information
on the former is not easily converted to net mass so I'm still not
clear on the recent net change, if any, in the global ice inventory.

--

FF

If this is global warming...
 

In article .com, wrote:

I've also found a lot of information indicating net losses of ice
in the Arctic, and a net loss in the world's glaciers, but
information
on the former is not easily converted to net mass so I'm still not
clear on the recent net change, if any, in the global ice inventory.

It's worth noting that, whatever the effects of loss of ice in the north polar
cap may be, rising sea level is *not* among them: the north polar cap is
floating, and melting all of it won't affect sea level.

The south polar cap is an entirely different story. Some Antarctic ice is
floating; some of it is on land, above sea level; and some of it is on land
*below* sea level -- that is, it's in the ocean and resting on the ocean
floor. Melting of ice in this last category will cause sea level to *drop*.

Whether sea levels will rise or fall in response to melting polar ice caps
depends on the relative proportion of submarine Antarctic ice to land-based
ice in Antartica and Greenland.

I've not been able to find data indicating what that proportion is.

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

If this is global warming...
 

Doug Miller wrote:
In article .com, wrote:


I've also found a lot of information indicating net losses of ice
in the Arctic, and a net loss in the world's glaciers, but
information
on the former is not easily converted to net mass so I'm still not
clear on the recent net change, if any, in the global ice inventory.


It's worth noting that, whatever the effects of loss of ice in the north polar
cap may be, rising sea level is *not* among them: the north polar cap is
floating, and melting all of it won't affect sea level.

The south polar cap is an entirely different story. Some Antarctic ice is
floating; some of it is on land, above sea level; and some of it is on land
*below* sea level -- that is, it's in the ocean and resting on the ocean
floor. Melting of ice in this last category will cause sea level to *drop*.

Whether sea levels will rise or fall in response to melting polar ice caps
depends on the relative proportion of submarine Antarctic ice to land-based
ice in Antartica and Greenland.

I've not been able to find data indicating what that proportion is.


So the only ice that, if melted, would raise the sea level is ice
resting on land masses. When one subtracts out ice on or in the ocean,
how much ice is left, and where is it? Also, that's the air temperature
over the land-based ice? Because if the temperature is 20 degrees F,
and global warming raised the temperature to 22, or even 25 degrees F,
it still isn't going to melt.

If this is global warming...
 

On Mar 8, 7:56 am, (Doug Miller) wrote:
In article .com, wrote:
I've also found a lot of information indicating net losses of ice
in the Arctic, and a net loss in the world's glaciers, but
information
on the former is not easily converted to net mass so I'm still not
clear on the recent net change, if any, in the global ice inventory.

It's worth noting that, whatever the effects of loss of ice in the north polar
cap may be, rising sea level is *not* among them: the north polar cap is
floating, and melting all of it won't affect sea level.

Not entirely correct because the mel****er is freshwater that is less
dense than the seawater displaced by the ice. But you are correct
in that effect is very small compared to the effect of an equal mass
of ice melting on land.

It is also worth noting that I used the term "sea ice" incorrectly.

By definitions, an ice sheet is on land, an ice shelf is ice that has
moved out onto water from a glacier or an ice sheet, and sea ice
forms on water by freezing or precipitation. The Arctic ice cap is
all or nearly all sea ice. Antarctica has all three.


The south polar cap is an entirely different story. Some Antarctic ice is
floating; some of it is on land, above sea level; and some of it is on land
*below* sea level -- that is, it's in the ocean and resting on the ocean
floor. Melting of ice in this last category will cause sea level to *drop*.

Does the ice in that category extend from the ocean floor to some not
insignificant height above mean sea level?


Whether sea levels will rise or fall in response to melting polar ice caps
depends on the relative proportion of submarine Antarctic ice to land-based
ice in Antartica and Greenland.

I've not been able to find data indicating what that proportion is.


Keep in mind also that if you reduce an ice shelf, the associated ice
sheet accelerates toward the sea.

My interest is not in estimating sea level change, but in estimating
the energy gained or lost by the phase change. That is to say,
isothermal warming or cooling.

--

FF

If this is global warming...
 

On Mar 8, 4:06 pm, Just Wondering wrote:
Doug Miller wrote:
In article .com, wrote:

I've also found a lot of information indicating net losses of ice
in the Arctic, and a net loss in the world's glaciers, but
information
on the former is not easily converted to net mass so I'm still not
clear on the recent net change, if any, in the global ice inventory.

It's worth noting that, whatever the effects of loss of ice in the north polar
cap may be, rising sea level is *not* among them: the north polar cap is
floating, and melting all of it won't affect sea level.

The south polar cap is an entirely different story. Some Antarctic ice is
floating; some of it is on land, above sea level; and some of it is on land
*below* sea level -- that is, it's in the ocean and resting on the ocean
floor. Melting of ice in this last category will cause sea level to *drop*.

Whether sea levels will rise or fall in response to melting polar ice caps
depends on the relative proportion of submarine Antarctic ice to land-based
ice in Antartica and Greenland.

I've not been able to find data indicating what that proportion is.

So the only ice that, if melted, would raise the sea level is ice
resting on land masses.

Pretty much so.

When one subtracts out ice on or in the ocean,
how much ice is left, and where is it?

I think addressing that question is part of the ICESAT mission:

http://icesat.gsfc.nasa.gov/intro.html

Also, that's the air temperature
over the land-based ice?

Variable, of course.

Because if the temperature is 20 degrees F,
and global warming raised the temperature to 22, or even 25 degrees F,
it still isn't going to melt.

And let's suppose the prevailing wind blows form west to east
across someplace like Greenland. If the west coast warms
a bit and melts a bit faster that could increase the local humidity
so that the air moving across it sees evaporative cooling and then
more cooling as it rises across the still below-freezing interior.
The result would be a transfer of ice from the coast to the
interior with no net loss and maybe even a short-term net gain
in total ice.

I think that sort of mechanism is the basis for some of the global
warming predictions of greater snow and ice accumulations in some
places.

Regardless, energy is conserved. If the Earth is warming there will
be lat least ONE of the following: less ice and snow, more humidity
or something will have a higher temperature. There is no intrinsic
reason why one or two of those could not remain stable or go the
other way, so long as the other(s) compensated.

The data in the paper I mentioned does not include Antarctic data
past the Spring of 2001. It also excludes some Antarctic ice that
does not affect, directly or indirectly, sea level as the focus of the
paper was on sea level change. Note that ice shelves do not
directly affect sea level but they do influence their associated
ice sheets that do affect sea level.

So if Leon was recollecting a net increase in Antarctic ice and snow
prior to 2002 or a recent increase in precipitation in the interior he
may well be right. That doesn't tell us about net global change,
one way or the other.

--

FF

If this is global warming...
 

In article .com, wrote:
On Mar 8, 7:56 am, (Doug Miller) wrote:
In article .com,
wrote:
I've also found a lot of information indicating net losses of ice
in the Arctic, and a net loss in the world's glaciers, but
information
on the former is not easily converted to net mass so I'm still not
clear on the recent net change, if any, in the global ice inventory.

It's worth noting that, whatever the effects of loss of ice in the north polar
cap may be, rising sea level is *not* among them: the north polar cap is
floating, and melting all of it won't affect sea level.

Not entirely correct because the mel****er is freshwater that is less
dense than the seawater displaced by the ice. But you are correct
in that effect is very small compared to the effect of an equal mass
of ice melting on land.

The difference in density between the mel****er and the ocean water won't
amount to a hill of beans. Yes, ocean water is more dense (by 2.7%), but
there's also a whole lot more of it, too, and the fresh water isn't going to
just lay there on top of it, either. Once it's mixed in, there won't be a
noticeable effect.

It is also worth noting that I used the term "sea ice" incorrectly.

By definitions, an ice sheet is on land, an ice shelf is ice that has
moved out onto water from a glacier or an ice sheet, and sea ice
forms on water by freezing or precipitation. The Arctic ice cap is
all or nearly all sea ice. Antarctica has all three.


The south polar cap is an entirely different story. Some Antarctic ice is
floating; some of it is on land, above sea level; and some of it is on land
*below* sea level -- that is, it's in the ocean and resting on the ocean
floor. Melting of ice in this last category will cause sea level to *drop*.

Does the ice in that category extend from the ocean floor to some not
insignificant height above mean sea level?

If it does, I can't find any indication of it in either of my world atlases.


Whether sea levels will rise or fall in response to melting polar ice caps
depends on the relative proportion of submarine Antarctic ice to land-based
ice in Antartica and Greenland.

I've not been able to find data indicating what that proportion is.

Keep in mind also that if you reduce an ice shelf, the associated ice
sheet accelerates toward the sea.

My interest is not in estimating sea level change, but in estimating
the energy gained or lost by the phase change. That is to say,
isothermal warming or cooling.

Hmmmm.... now that's an interesting thought. Hadn't considered that
perspective. Certainly, the ice absorbs heat as it melts -- a lot of heat (80
calories per gram) -- whether that's significant on a planetary scale may be a
different matter.

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

If this is global warming...
 

On Mar 9, 8:06 am, (Doug Miller) wrote:
In article .com, wrote:
On Mar 8, 7:56 am, (Doug Miller) wrote:
In article .com,
wrote:

...

It's worth noting that, whatever the effects of loss of ice in the north polar
cap may be, rising sea level is *not* among them: the north polar cap is
floating, and melting all of it won't affect sea level.

Not entirely correct because the mel****er is freshwater that is less
dense than the seawater displaced by the ice. But you are correct
in that effect is very small compared to the effect of an equal mass
of ice melting on land.

The difference in density between the mel****er and the ocean water won't
amount to a hill of beans. Yes, ocean water is more dense (by 2.7%), but
there's also a whole lot more of it, too, and the fresh water isn't going to
just lay there on top of it, either. Once it's mixed in, there won't be a
noticeable effect.

I don't think it matters whether the water molecules are
all in one blob or distributed over the entire ocean. So
the effect would be 2.7% of the volume of the mel****er
which we agree is not significant.

...

The south polar cap is an entirely different story. Some Antarctic ice is
floating; some of it is on land, above sea level; and some of it is on land
*below* sea level -- that is, it's in the ocean and resting on the ocean
floor. Melting of ice in this last category will cause sea level to *drop*.

Does the ice in that category extend from the ocean floor to some not
insignificant height above mean sea level?

If it does, I can't find any indication of it in either of my world atlases.


NASA probably has the data. Unfortunately net-vandals have forced
NASA into computer security practices that make it harder to get
the data out of the Distributed Data Archives free access to which
NASA was trying to provide to the world. It is hard to overestimate
the damage done to the world by spammers, crackers, and other
net-vandals.


...

My interest is not in estimating sea level change, but in estimating
the energy gained or lost by the phase change. That is to say,
isothermal warming or cooling.

Hmmmm.... now that's an interesting thought. Hadn't considered that
perspective. Certainly, the ice absorbs heat as it melts -- a lot of heat (80
calories per gram) -- whether that's significant on a planetary scale may be a
different matter.


I think that a comparison with how much the air temperature would
rise or fall if all of the heat were lost or absorbed by the air alone
might
be instructive.

Of course the latent heat of evaporation and the high heat capacity
of water overwhelms that. Small global changes in humidity or ocean
temperature absorb or emit huge amounts of heat. That is a real good
thing as it provides us with stability. It also make it devilishly
difficult
to tell if the Earth is warming or cooling and at what rate, without
very long observation, unless the rate is dangerously large.

--

FF

If this is global warming...
 

If this is global warming...
 

On Mar 9, 1:21 pm, Just Wondering wrote:
wrote:

Of course the latent heat of evaporation and the high heat capacity
of water overwhelms that. Small global changes in humidity or ocean
temperature absorb or emit huge amounts of heat. That is a real good
thing as it provides us with stability. It also make it devilishly
difficult to tell if the Earth is warming or cooling and at what rate,

without very long observation, unless the rate is dangerously large.



I suspect it also oretty much drowns out the effect of minute changes in
atmospheric CO2 concentrations.

Depends what you mean by drown out.

Minute changes in CO2 would only have a minute
effect in the first place.

Those aformentioned phenomena do not change
the rates at which the Earth absorbs or emits energy.
So they don't nullify the effect of changes in
those rates regardless of what causes those changes,
Milininkov cycles, solar variation, volcanism, asteroid
impact, variations in the concentration of Greenhouse
gases etc.

They slow the effect of those changes. If the small
observed variation in insolation causes an observable
change then certainly the much larger variation in
CO2 concentration will too--unless the net effect of
those two is offset by yet another changing parameter
like global dimming form stratospheric particulates and
ice crystals.

--

FF