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Guest

Mon Jan 09, 2017 12:07 pm   



On Monday, January 9, 2017 at 8:17:46 PM UTC+11, Tom Gardner wrote:
Quote:
On 09/01/17 05:18, rickman wrote:
Even funnier is the idea that an engineer analyzing climate makes fun of a noted
science writer because he was trained as a chemist. Talk about irony.


Experts? We don't need no steenkin' experts.

(And we should just have newly minted grads designing
complex electronic/software systems. Not.)


I did pretty well as a graduate student. I did a lot better after I'd learned a bit more. There's nothing wrong with newly minted graduates - what they've been taught isn't usually all that useful, but the good ones have found out how to find what they need to know. Universities don't seem to be entirely aware that they impart this skill, and don't seem to have found out any way to test for it, but it's what universities are actually good for.

--
Bill Sloman, Sydney


Guest

Mon Jan 09, 2017 12:22 pm   



Quote:
Well, he was a chemist, so what do you expect? ;)

Now, *that's* funny!


I wasn't needling Bill, if that's what you mean. After numerous tries I gave up and killfiled him ages ago. (Or rather added him to a Tbird filter that automatically marks a few people's posts as having been read. On Google I have to skip them manually, but it's a habit by now.)

Cheers

Phil Hobbs


Guest

Mon Jan 09, 2017 1:12 pm   



On Monday, January 9, 2017 at 9:22:10 PM UTC+11, pcdh...@gmail.com wrote:
Quote:
Well, he was a chemist, so what do you expect? ;)

Now, *that's* funny!

I wasn't needling Bill, if that's what you mean. After numerous tries I gave up and killfiled him ages ago. (Or rather added him to a Tbird filter that automatically marks a few people's posts as having been read. On Google I have to skip them manually, but it's a habit by now.)


Dear me. Jim Thompson I'm not worried about, but having Phil Hobbs kill-file me is bit depressing.

--
Bill Sloman, Sydney


Guest

Mon Jan 09, 2017 3:05 pm   



On Monday, January 9, 2017 at 11:31:01 PM UTC+11, Jasen Betts wrote:
Quote:
On 2017-01-08, John Larkin <jjlarkin_at_highlandtechnology.com> wrote:
On Sun, 8 Jan 2017 15:34:41 -0500, Phil Hobbs
pcdhSpamMeSenseless_at_electrooptical.net> wrote:

On 01/08/2017 03:27 PM, John Larkin wrote:
On Sun, 8 Jan 2017 14:47:59 -0500, Phil Hobbs
pcdhSpamMeSenseless_at_electrooptical.net> wrote:

On 01/08/2017 11:35 AM, John Larkin wrote:
On Sun, 8 Jan 2017 08:04:21 -0800 (PST), Wanderer
wanderer_at_dialup4less.com> wrote:

My favorite thing written on climate change was written by Isaac Asimov for the February 22, 1975 issue of the TV Guide and called "The Weather Machine". It was reprinted as "The Big Weather Change" in "The Beginning and the End" a collection of Isaac Asimov essays.

Now I'm posting this because I think people should be reading this book. You can get the book here.
https://www.abebooks.com/servlet/SearchResults?sts=t&an=Asimov&tn=The+Beginning+and+the+End&kn=&isbn
In the essay, Asimov writes,

"During the last million years, the world has seen huge oscillations of warm and cold. Sometimes the Arctic Ocean is open water and then it supplies water vapor which falls on the surrounding land areas as snow. If there is then a small drop in general temperature for a prolonged stretch of time not all the snow that falls each winter will melt each summer.

The snow then accumulates from year to year and squeezes down under its own weight to form glaciers. The glacier ice reflects Sunlight more efficiently than bare ground does and cools the Earth further, so that still less of the snow that falls in the winter is melted, and the glaciers advance southward.

Eventually, the temperature drops to the point where the Arctic Ocean freezes over and the supply of water vapor is cut off. Less snow falls, so that the summer melting becomes more effective and the glaciers begin to retreat. The retreat reduces the ice cover, allows the Earth to warm, and accelerates the retreat further. When it grows warm enough for the ice on Arctic Ocean to melt, it starts all over."

Now look at this graph from the EPA. It shows the CO2/Temperature cycle without the human effect.

https://www.epa.gov/sites/production/files/styles/medium/public/2016-07/co2temp800kyrs-large.jpg

I see a triangle wave with some disturbances and noise on it and starting around 450 thousand years ago. The present day is right at the point where the North Pole melts and turns on the Arctic Ocean's snow making machine.

Of course humans have had an effect and that is shown in this graph.

https://www.epa.gov/sites/production/files/2016-07/ghgconc2000-large.jpg

But what does that change? The Arctic Ice Cap is still going to melt and the Arctic Ocean's snow making machine is still going to turn on. I think it would just change the period of the triangle wave. Instead of the Arctic Ice Cap returning in 100,000 years, it might return in a million years or it might never return. We end up with stable halo of ice around the North Pole.

So when I see these ding dongs yelling, "The North Pole is melting! Science! Science! Scary! Scary! Gives us $100 billion/year and we'll save you!" I think it's bullshit. You're not going to stop the North Pole from melting and the North Pole melting doesn't prove anything. That's just part of the natural cycle that's been going on for half a million years. I also think the bozos yelling, "It's colder and snowing more this winter! We've have nothing to worry about!" No, that's what happens when the North Pole melts and it is going to get worse. What makes all this nonsense worse is that we new about it 40 years ago.

Asimov did the too-common thing of assuming that feedbacks always
cause oscillation. Control theory is real and involves more than
qualitative speculation. The "oscillations" are more likely to be
caused by external forcings.

Well, he was a chemist, so what do you expect? ;)

There are only a few cases of chemical oscillations. They are
extremely rare, so Asimov should have been biased towards gradual
equilibrium.


https://www.youtube.com/watch?v=_gyzhvMLImg


I don't know of any cases of purely thermal heat-driven oscillations.



Steam engines. ;)

But in the absence of mass motion, heat flow is governed by a PDE that's
first order in time and has real-valued coefficients, so it doesn't give
rise to imaginary exponentials. (Schroedinger is first order in time as
well, but has an i in it, so it has no real-exponential solutions.)

Cheers

Phil Hobbs

There is the famous R-C circuit with voltage gain

www.cypress.com/file/123196

and it seems to me that there ought to be a thermal equivalent. But
we'd still need more stuff to make an oscillator.

what's the thermal equivalent of a non-grounded capacitor ?


Pretty much everything. The thermal equivalent of a ground might be the back-ground microwave radiation - anything that's radiating into a empty sky equilibrates with that (as well as everything else in sight).

Anything you actually work with has a thermal capacity and a thermal resistance back to local ambient. Heat pipes offer fairly low thermal resistance paths back to ambient, usually via a decent-sized heat-sink.

If you had an object immersed in a bath of a pure fluid heated to it's local boiling point the local ambient temperature would be pretty well defined, but there would still be a thermal resistance from the centre of the object to that local ambient.

--
Bill Sloman, Sydney

Tom Gardner
Guest

Mon Jan 09, 2017 4:17 pm   



On 09/01/17 05:18, rickman wrote:
Quote:
Even funnier is the idea that an engineer analyzing climate makes fun of a noted
science writer because he was trained as a chemist. Talk about irony.


Experts? We don't need no steenkin' experts.

(And we should just have newly minted grads designing
complex electronic/software systems. Not.)

Lasse Langwadt Christense
Guest

Mon Jan 09, 2017 7:03 pm   



Den mandag den 9. januar 2017 kl. 17.39.04 UTC+1 skrev John Larkin:
Quote:
On Sun, 8 Jan 2017 20:15:43 -0800 (PST), whit3rd <whit3rd_at_gmail.com
wrote:

On Sunday, January 8, 2017 at 12:27:42 PM UTC-8, John Larkin wrote:
On Sun, 8 Jan 2017 14:47:59 -0500, Phil Hobbs

There are only a few cases of chemical oscillations. They are
extremely rare, so Asimov should have been biased towards gradual
equilibrium.

https://www.youtube.com/watch?v=_gyzhvMLImg

I don't know of any cases of purely thermal heat-driven oscillations.

True, the quasi-periodic fires in California's brushlands are not purely
thermal (there's a biological growth/deadwood element).

More generally applicable, is the accumulation of instability: any slight
fire (human or natural) causes an abnormally high response, if the last
fire in the area was many years ago... but not if all the brush
burned last year.

That kind of instability gives rise to catastrophes, and is a compelling reason
for controlled burns to limit the brush accumulations. In the 1970s, it
wasn't known that CO2 accumulation would occur (sinks, like ocean uptake, weren't
quantified until later). We're currently seeking ways to limit CO2 accumulation.

The local "experts" (journalists and politicians) tend to blame the
big fires, and the droughts, on CO2 AGW.

The rainfall/snowpack pattern hasn't changed since good records were
collected in the mid 1800's.

Before westerners showed up, about 10% of the land area of California
burned every year, and it wasn't a bug deal. The brush burned and the
mature trees survived. That was before fire departments and aerial
tankers and flame retardents and megabuck houses built in the forests.
Big fuel loads make big fires, and they burn everything.


afaiu they have started letting small controlled fires burn, because
some species of trees turned out to be dependent on the fires and were
going extinct

and small controlled fires are less dangerous that letting all the dead
trees etc. accumulate and make a fire that much bigger and unstoppable

Jasen Betts
Guest

Mon Jan 09, 2017 7:19 pm   



On 2017-01-08, John Larkin <jjlarkin_at_highlandtechnology.com> wrote:
Quote:
On Sun, 8 Jan 2017 15:34:41 -0500, Phil Hobbs
pcdhSpamMeSenseless_at_electrooptical.net> wrote:

On 01/08/2017 03:27 PM, John Larkin wrote:
On Sun, 8 Jan 2017 14:47:59 -0500, Phil Hobbs
pcdhSpamMeSenseless_at_electrooptical.net> wrote:

On 01/08/2017 11:35 AM, John Larkin wrote:
On Sun, 8 Jan 2017 08:04:21 -0800 (PST), Wanderer
wanderer_at_dialup4less.com> wrote:

My favorite thing written on climate change was written by Isaac Asimov for the February 22, 1975 issue of the TV Guide and called "The Weather Machine". It was reprinted as "The Big Weather Change" in "The Beginning and the End" a collection of Isaac Asimov essays.

Now I'm posting this because I think people should be reading this book. You can get the book here.
https://www.abebooks.com/servlet/SearchResults?sts=t&an=Asimov&tn=The+Beginning+and+the+End&kn=&isbn=

In the essay, Asimov writes,

"During the last million years, the world has seen huge oscillations of warm and cold. Sometimes the Arctic Ocean is open water and then it supplies water vapor which falls on the surrounding land areas as snow. If there is then a small drop in general temperature for a prolonged stretch of time not all the snow that falls each winter will melt each summer.

The snow then accumulates from year to year and squeezes down under its own weight to form glaciers. The glacier ice reflects Sunlight more efficiently than bare ground does and cools the Earth further, so that still less of the snow that falls in the winter is melted, and the glaciers advance southward.

Eventually, the temperature drops to the point where the Arctic Ocean freezes over and the supply of water vapor is cut off. Less snow falls, so that the summer melting becomes more effective and the glaciers begin to retreat. The retreat reduces the ice cover, allows the Earth to warm, and accelerates the retreat further. When it grows warm enough for the ice on Arctic Ocean to melt, it starts all over."

Now look at this graph from the EPA. It shows the CO2/Temperature cycle without the human effect.

https://www.epa.gov/sites/production/files/styles/medium/public/2016-07/co2temp800kyrs-large.jpg

I see a triangle wave with some disturbances and noise on it and starting around 450 thousand years ago. The present day is right at the point where the North Pole melts and turns on the Arctic Ocean's snow making machine.

Of course humans have had an effect and that is shown in this graph.

https://www.epa.gov/sites/production/files/2016-07/ghgconc2000-large.jpg

But what does that change? The Arctic Ice Cap is still going to melt and the Arctic Ocean's snow making machine is still going to turn on. I think it would just change the period of the triangle wave. Instead of the Arctic Ice Cap returning in 100,000 years, it might return in a million years or it might never return. We end up with stable halo of ice around the North Pole.

So when I see these ding dongs yelling, "The North Pole is melting! Science! Science! Scary! Scary! Gives us $100 billion/year and we'll save you!" I think it's bullshit. You're not going to stop the North Pole from melting and the North Pole melting doesn't prove anything. That's just part of the natural cycle that's been going on for half a million years. I also think the bozos yelling, "It's colder and snowing more this winter! We've have nothing to worry about!" No, that's what happens when the North Pole melts and it is going to get worse. What makes all this nonsense worse is that we new about it 40 years ago.

Asimov did the too-common thing of assuming that feedbacks always
cause oscillation. Control theory is real and involves more than
qualitative speculation. The "oscillations" are more likely to be
caused by external forcings.

Well, he was a chemist, so what do you expect? ;)

There are only a few cases of chemical oscillations. They are
extremely rare, so Asimov should have been biased towards gradual
equilibrium.


https://www.youtube.com/watch?v=_gyzhvMLImg


I don't know of any cases of purely thermal heat-driven oscillations.



Steam engines. ;)

But in the absence of mass motion, heat flow is governed by a PDE that's
first order in time and has real-valued coefficients, so it doesn't give
rise to imaginary exponentials. (Schroedinger is first order in time as
well, but has an i in it, so it has no real-exponential solutions.)

Cheers

Phil Hobbs

There is the famous R-C circuit with voltage gain

www.cypress.com/file/123196

and it seems to me that there ought to be a thermal equivalent. But
we'd still need more stuff to make an oscillator.


what's the thermal equivalent of a non-grounded capacitor ?

--
This email has not been checked by half-arsed antivirus software

Jeroen Belleman
Guest

Mon Jan 09, 2017 8:27 pm   



On 2017-01-09 14:05, bill.sloman_at_ieee.org wrote:
Quote:
On Monday, January 9, 2017 at 11:31:01 PM UTC+11, Jasen Betts wrote:
On 2017-01-08, John Larkin <jjlarkin_at_highlandtechnology.com
wrote:


[Snip!]

Quote:
There is the famous R-C circuit with voltage gain

www.cypress.com/file/123196

and it seems to me that there ought to be a thermal equivalent.
But we'd still need more stuff to make an oscillator.

what's the thermal equivalent of a non-grounded capacitor ?

Pretty much everything. The thermal equivalent of a ground might be
the back-ground microwave radiation - anything that's radiating into
a empty sky equilibrates with that (as well as everything else in
sight).

Anything you actually work with has a thermal capacity and a thermal
resistance back to local ambient. Heat pipes offer fairly low thermal
resistance paths back to ambient, usually via a decent-sized
heat-sink.
[...]


I think you misunderstood Jasen's point. Do we have a device
that gets hotter at the hot side when we heat the cool side?
(Without a reversal of the gradient across the device, that is.)

It's certainly possible with active devices, heat pumps or
some such, but that would be cheating.

Jeroen Belleman

George Herold
Guest

Mon Jan 09, 2017 9:43 pm   



On Monday, January 9, 2017 at 11:55:21 AM UTC-5, John Larkin wrote:
Quote:
On Mon, 9 Jan 2017 09:17:41 +0000, Tom Gardner
spamjunk_at_blueyonder.co.uk> wrote:

On 09/01/17 05:18, rickman wrote:
Even funnier is the idea that an engineer analyzing climate makes fun of a noted
science writer because he was trained as a chemist. Talk about irony.


Experts? We don't need no steenkin' experts.

There are vast regions of non-experimental "science" where the
overwhelming concensus is usually wrong. It changes semi-periodically,
roughly once per generation, so it might occasionally be right, by
accident.

Oh my..
*** thread shift .. but it relates to food and that is
always permissible (according to my copy of the SED bylaws.)
***
I was reading this article about the evils of sugar, and how (they) think
that nutritionalist's got the obesity question wrong.
It's not about energy inbalance, but a hormonal response to carbs.
(I can't recall where I read it.)

George H.
Quote:

Asimov's predictions were dire and wrong. Nothing new there.



(And we should just have newly minted grads designing
complex electronic/software systems. Not.)

I pretty much despair of recent EE grads designing anything sensible.
I've interviewed too many young EEs who can't figure out a simple
voltage divider, much less a transistor or an opamp. Most skipped the
field theory and control theory and s+s courses because they are hard,
and are electives now. I must have interviewed 50 of them, and found
one (a young woman who graduated from a college in Mexico) who
actually understands electricity; I hired her.

That's a separate rant.


--

John Larkin Highland Technology, Inc

lunatic fringe electronics


George Herold
Guest

Mon Jan 09, 2017 10:54 pm   



On Monday, January 9, 2017 at 3:08:14 PM UTC-5, John Larkin wrote:
Quote:
On Mon, 9 Jan 2017 11:43:00 -0800 (PST), George Herold
gherold_at_teachspin.com> wrote:

On Monday, January 9, 2017 at 11:55:21 AM UTC-5, John Larkin wrote:
On Mon, 9 Jan 2017 09:17:41 +0000, Tom Gardner
spamjunk_at_blueyonder.co.uk> wrote:

On 09/01/17 05:18, rickman wrote:
Even funnier is the idea that an engineer analyzing climate makes fun of a noted
science writer because he was trained as a chemist. Talk about irony.


Experts? We don't need no steenkin' experts.

There are vast regions of non-experimental "science" where the
overwhelming concensus is usually wrong. It changes semi-periodically,
roughly once per generation, so it might occasionally be right, by
accident.
Oh my..
*** thread shift .. but it relates to food and that is
always permissible (according to my copy of the SED bylaws.)
***
I was reading this article about the evils of sugar, and how (they) think
that nutritionalist's got the obesity question wrong.
It's not about energy inbalance, but a hormonal response to carbs.
(I can't recall where I read it.)

George H.

Some decades carbs are good, and some decades they are poison. Ditto
fats, dairy, meat, salt, whatever.

I guess I have a basic "faith" that science will eventually get it right..
or at least righter. But I can understand your mistrust.

The article talked about how there was a paradigm shift in the 40's
when the center of science left Germany and came here. The energy balance
argument makes sense.. energy in - out = stored. But we've known
for a while that carbs cause a hormonal response too... more insulin,
which leads to fat storage.

Quote:

Some "sciences", where there is no danger of being embarassed by
experiment, are necessarily fad-driven. You need to keep coming up
with new stuff if you want to publish.

I see fads in all the sciences.
(well I pay the most attention to solid state physics.)
Topological insulators was last decades fad, I don't know what
it is now. (I haven't been to a conference in a while.)

George H.


Quote:




--

John Larkin Highland Technology, Inc
picosecond timing precision measurement

jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com



Guest

Mon Jan 09, 2017 11:15 pm   



Quote:
I think you misunderstood Jasen's point. Do we have a device
that gets hotter at the hot side when we heat the cool side?
(Without a reversal of the gradient across the device, that is.)


You can't make heat flow spontaneously from cold to hot, but in almost any situation involving steady-state heat flow, warming up the cold side does cause the hot side to warm too. (Heat sinks and transistor junctions come to mind.)

Cheers

Phil Hobbs

John Larkin
Guest

Mon Jan 09, 2017 11:30 pm   



On 9 Jan 2017 12:19:09 GMT, Jasen Betts <jasen_at_xnet.co.nz> wrote:

Quote:
On 2017-01-08, John Larkin <jjlarkin_at_highlandtechnology.com> wrote:
On Sun, 8 Jan 2017 15:34:41 -0500, Phil Hobbs
pcdhSpamMeSenseless_at_electrooptical.net> wrote:

On 01/08/2017 03:27 PM, John Larkin wrote:
On Sun, 8 Jan 2017 14:47:59 -0500, Phil Hobbs
pcdhSpamMeSenseless_at_electrooptical.net> wrote:

On 01/08/2017 11:35 AM, John Larkin wrote:
On Sun, 8 Jan 2017 08:04:21 -0800 (PST), Wanderer
wanderer_at_dialup4less.com> wrote:

My favorite thing written on climate change was written by Isaac Asimov for the February 22, 1975 issue of the TV Guide and called "The Weather Machine". It was reprinted as "The Big Weather Change" in "The Beginning and the End" a collection of Isaac Asimov essays.

Now I'm posting this because I think people should be reading this book. You can get the book here.
https://www.abebooks.com/servlet/SearchResults?sts=t&an=Asimov&tn=The+Beginning+and+the+End&kn=&isbn=

In the essay, Asimov writes,

"During the last million years, the world has seen huge oscillations of warm and cold. Sometimes the Arctic Ocean is open water and then it supplies water vapor which falls on the surrounding land areas as snow. If there is then a small drop in general temperature for a prolonged stretch of time not all the snow that falls each winter will melt each summer.

The snow then accumulates from year to year and squeezes down under its own weight to form glaciers. The glacier ice reflects Sunlight more efficiently than bare ground does and cools the Earth further, so that still less of the snow that falls in the winter is melted, and the glaciers advance southward.

Eventually, the temperature drops to the point where the Arctic Ocean freezes over and the supply of water vapor is cut off. Less snow falls, so that the summer melting becomes more effective and the glaciers begin to retreat. The retreat reduces the ice cover, allows the Earth to warm, and accelerates the retreat further. When it grows warm enough for the ice on Arctic Ocean to melt, it starts all over."

Now look at this graph from the EPA. It shows the CO2/Temperature cycle without the human effect.

https://www.epa.gov/sites/production/files/styles/medium/public/2016-07/co2temp800kyrs-large.jpg

I see a triangle wave with some disturbances and noise on it and starting around 450 thousand years ago. The present day is right at the point where the North Pole melts and turns on the Arctic Ocean's snow making machine.

Of course humans have had an effect and that is shown in this graph.

https://www.epa.gov/sites/production/files/2016-07/ghgconc2000-large.jpg

But what does that change? The Arctic Ice Cap is still going to melt and the Arctic Ocean's snow making machine is still going to turn on. I think it would just change the period of the triangle wave. Instead of the Arctic Ice Cap returning in 100,000 years, it might return in a million years or it might never return. We end up with stable halo of ice around the North Pole.

So when I see these ding dongs yelling, "The North Pole is melting! Science! Science! Scary! Scary! Gives us $100 billion/year and we'll save you!" I think it's bullshit. You're not going to stop the North Pole from melting and the North Pole melting doesn't prove anything. That's just part of the natural cycle that's been going on for half a million years. I also think the bozos yelling, "It's colder and snowing more this winter! We've have nothing to worry about!" No, that's what happens when the North Pole melts and it is going to get worse. What makes all this nonsense worse is that we new about it 40 years ago.

Asimov did the too-common thing of assuming that feedbacks always
cause oscillation. Control theory is real and involves more than
qualitative speculation. The "oscillations" are more likely to be
caused by external forcings.

Well, he was a chemist, so what do you expect? ;)

There are only a few cases of chemical oscillations. They are
extremely rare, so Asimov should have been biased towards gradual
equilibrium.


https://www.youtube.com/watch?v=_gyzhvMLImg


I don't know of any cases of purely thermal heat-driven oscillations.



Steam engines. ;)

But in the absence of mass motion, heat flow is governed by a PDE that's
first order in time and has real-valued coefficients, so it doesn't give
rise to imaginary exponentials. (Schroedinger is first order in time as
well, but has an i in it, so it has no real-exponential solutions.)

Cheers

Phil Hobbs

There is the famous R-C circuit with voltage gain

www.cypress.com/file/123196

and it seems to me that there ought to be a thermal equivalent. But
we'd still need more stuff to make an oscillator.

what's the thermal equivalent of a non-grounded capacitor ?


There is none. There is no thermal equivalent of a Farady shield.

But one chunk metal can be placed on or inside another, to approximate
some simple circuits. Achieving a step overshoot, like an RC can do,
may be impossible.

Without adding motion, there is no thermal transmission line, except
the dreadful RCRC type. Thermal systems are dull.



--

John Larkin Highland Technology, Inc

lunatic fringe electronics

John Larkin
Guest

Mon Jan 09, 2017 11:38 pm   



On Sun, 8 Jan 2017 20:15:43 -0800 (PST), whit3rd <whit3rd_at_gmail.com>
wrote:

Quote:
On Sunday, January 8, 2017 at 12:27:42 PM UTC-8, John Larkin wrote:
On Sun, 8 Jan 2017 14:47:59 -0500, Phil Hobbs

There are only a few cases of chemical oscillations. They are
extremely rare, so Asimov should have been biased towards gradual
equilibrium.

https://www.youtube.com/watch?v=_gyzhvMLImg

I don't know of any cases of purely thermal heat-driven oscillations.

True, the quasi-periodic fires in California's brushlands are not purely
thermal (there's a biological growth/deadwood element).

More generally applicable, is the accumulation of instability: any slight
fire (human or natural) causes an abnormally high response, if the last
fire in the area was many years ago... but not if all the brush
burned last year.

That kind of instability gives rise to catastrophes, and is a compelling reason
for controlled burns to limit the brush accumulations. In the 1970s, it
wasn't known that CO2 accumulation would occur (sinks, like ocean uptake, weren't
quantified until later). We're currently seeking ways to limit CO2 accumulation.


The local "experts" (journalists and politicians) tend to blame the
big fires, and the droughts, on CO2 AGW.

The rainfall/snowpack pattern hasn't changed since good records were
collected in the mid 1800's.

Before westerners showed up, about 10% of the land area of California
burned every year, and it wasn't a bug deal. The brush burned and the
mature trees survived. That was before fire departments and aerial
tankers and flame retardents and megabuck houses built in the forests.
Big fuel loads make big fires, and they burn everything.


--

John Larkin Highland Technology, Inc

lunatic fringe electronics

George Herold
Guest

Mon Jan 09, 2017 11:40 pm   



On Monday, January 9, 2017 at 4:15:47 PM UTC-5, pcdh...@gmail.com wrote:
Quote:
I think you misunderstood Jasen's point. Do we have a device
that gets hotter at the hot side when we heat the cool side?
(Without a reversal of the gradient across the device, that is.)

You can't make heat flow spontaneously from cold to hot, but in almost any situation involving steady-state heat flow, warming up the cold side does cause the hot side to warm too. (Heat sinks and transistor junctions come to mind.)

Cheers

Phil Hobbs


OK Now I'm interpreting someone's interpretation.. bad... but I thought Jason meant
a "thermal" capacitance not connected to any heat bath. So no thermal connections
(through a thermal resistance) to "zero" temperature. A hunk of something floating
in a heat capacity chamber is the as close as I can come.
(By a heat capacity chamber I mean a vacuum space use to measure heat capacity.)

George H.

John Larkin
Guest

Mon Jan 09, 2017 11:55 pm   



On Mon, 9 Jan 2017 09:17:41 +0000, Tom Gardner
<spamjunk_at_blueyonder.co.uk> wrote:

Quote:
On 09/01/17 05:18, rickman wrote:
Even funnier is the idea that an engineer analyzing climate makes fun of a noted
science writer because he was trained as a chemist. Talk about irony.


Experts? We don't need no steenkin' experts.


There are vast regions of non-experimental "science" where the
overwhelming concensus is usually wrong. It changes semi-periodically,
roughly once per generation, so it might occasionally be right, by
accident.

Asimov's predictions were dire and wrong. Nothing new there.


Quote:

(And we should just have newly minted grads designing
complex electronic/software systems. Not.)


I pretty much despair of recent EE grads designing anything sensible.
I've interviewed too many young EEs who can't figure out a simple
voltage divider, much less a transistor or an opamp. Most skipped the
field theory and control theory and s+s courses because they are hard,
and are electives now. I must have interviewed 50 of them, and found
one (a young woman who graduated from a college in Mexico) who
actually understands electricity; I hired her.

That's a separate rant.


--

John Larkin Highland Technology, Inc

lunatic fringe electronics

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