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Comment Re:Way to state the obvious (Score 1) 552

The point to note here is that at equlibrium (which must occur), flux in = flux out. That means that under no circumtances will the temperature ever exceed the input.

Again, you are confusing heat and temperature. The input is energy (heat), the input is not temperature. No one who has grasped basic thermodynamics would take your argument seriously after that fundamental mistake. You seem to be just stringing together scientific jargon in a nonsensical way to reach a conclusion you like.

In a different post you claim that convection plays a significant role in the heat loss of the Earth. The upper atmosphere is close to being a vacuum. At a high enough altitude the amount of heat transfer due to conduction and convection is negligible. Do yourself a favor and Google(thermosphere).

You claimed the fine Nature article was wrong because it was based on radiative forcing yet you have never defined what you mean by that term. Your definition seems to be at odds with the definition given by the Wikipedia. The term was never used in the article nor was it used in the two references you gave to back up your claim that radiative forcing had been debunked.

Again, I ask, in the Earth-Sun system what is the "input" temperature if it is not the temperature of the surface of the Sun?

And BTW I do have a Ph.D. in physics. A Nobel Laureate was the chairman of my thesis defense and I've study thermodynamics with some of the leading experts in the world.

***click***

Comment Re:Way to state the obvious (Score 1) 552

And [At?] equilibrium, the "limiting temperature", assuming a black body, is the temperature that corresponds to radiating the same amount of energy as the input. Anything else is nonsensical.

0) Requiring your arguments to be in accord with basic physics is not nit picking.

1) The Earth is not in thermal equilibrium with the Sun. If it were then it would be at the same temperature as the surface of the Sun. The only reason life can exist on Earth is because of the gradient caused by the Earth not being in thermal equilibrium with the Sun.

2) A black body is not the same thing as a perfect insulator. They are opposites in a way. A perfect insulator would block all radiative cooling (or else it would not be a very good insulator). My point is that the limiting temperature is a function of the insulating properties of the Earth. It is not an intrinsic property of the strength of solar heating.

If you treat the Earth as a black body you are explicitly ignoring all insulation effects. IOW you are ignoring all greenhouse effects. In simple layman's terms, how hot something gets when it is left out in the sun depends greatly on how well it is insulated. Even the temperature inside a conventional greenhouse is highly dependent on how well it is insulated.

3) When you say a black body in equilibrium radiates the same amount of energy it absorbs, you seem to be repeating the definition of radiative forcing, not debunking it.

If you believe there is a limiting temperature to the strength of solar heating that is much less than the temperature of the surface of the Sun, please tell us what that temperature limit is.

Neither of the fine articles linked to in the summary nor either or your two references even mention radiative forcing. If you have sources that don't conflict with basic physics which debunk whatever it is you mean by radiative forcing I would like to see them. Perhaps part of the problem is that your definition of radiative forcing differs from the definition given by the Wikipedia. So far you have given nothing more than your opinion that the authors of the Nature article made a serious (and probably job-threatening) mistake.

Comment Re:Way to state the obvious (Score 1) 552

You've picked your nit accurately and with great force.

The Slashdotter Jane Q. Public had repeatedly claimed the Nature article was bunkum because it was based on the concept of radiative forcing. For example:

I should also point out that the entire concept of "radiative forcing" this is based on was refuted a few years ago, and so far that refutation has not been successfully challenged.

To me, it would be rather earth shattering news if a Nature article was based on a theory that was debunked five years ago. I looked up radiative forcing to try to find out what JQP was talking about. JQP was kind enough to supply references for the so-called refutation which should have made my task easier. The references were utter nonsense that defied basic physics with silly hand waving arguments.

Since JQP's erroneous comments were not moderated into oblivion, correcting their spread of grossly unscientific misinformation which cast aspersions on the fine Nature article is about as far from nit-picking as one can get.

Comment Re:Way to state the obvious (Score 1) 552

the temperature of the box will rise without limit

wow. Total Science Fail

Given the assumptions of a perfect insulator and constant energy input, what is the limiting temperature? What happens to energy conservation when that temperature limit is reached?

As I said before, there are, of course, limits due to imperfect insulation and the finite temperature of the surface of the Sun but these limits are far above the temperatures reached in the upper atmosphere.

What is the limiting temperature of the strength of solar heating?

What is the limiting temperature of a perfectly insulated box with a constant input of energy?

Comment Re:Way to state the obvious (Score 3, Interesting) 552

Neither one of the fine articles linked to in the summary mention radiative forcing. Neither do either of the two references you cite as proofs that radiative forcing has been debunked. The Wikipedia describes radiative forcing as:

In climate science, radiative forcing is defined as the difference of radiant energy received by the earth and energy radiated back to space.

There is no mention of it being refuted (or even controversial); not in the Wikipedia article and not in the two references you cited. In fact, since radiative forcing is a rather simple definition it is hard to imagine how it could be refutable.

Furthermore, this reference of yours, despite having pretty pictures, seems to be based on utter nonsense with the main point being:

Internal [actual greenhouse] temperature cannot exceed maximum strength of solar heating input.

This is utter nonsense because it makes a direct comparison between heat and temperature. It would be helpful if the article mentioned what the temperature limit of the strength of solar heating was. But if they did that, the utter nonsense would be apparent because the temperature of a solar furnace can be many thousands of degrees (either Celsius or Fahrenheit) so if there is limiting temperature, it must be so high as to be meaningless in discussions of global warming.

Another way to see it is that if you can trap solar energy in a box that has perfect insulation (energy comes in but it does not go out) then the temperature of the box will rise without limit. Of course there is no such thing as a perfect insulator so there are limits to how high a temperature you can achieve but these limits are not a direct property of the solar radiation. There is a temperature limit, of a sort, to solar radiation but the limit is the temperature of the surface of the Sun, which again has no bearing on discussion of global warming.

Comment This is probably not a big deal (Score 4, Informative) 264

What they are exploiting is that in naive implementations of RSA the amount of computer power needed during en/decryption varies with each binary digit in the key. If the digit is zero then no computation is done and if it is one that a tight loop is executed.

There have been other side channel attacks that exploit this weakness in naive implementations. The obvious fix is to slightly change the algorithm so the same computation is done whether the digit is a zero or a one. This reduces the efficiency by a factor of two but it makes these side channel attacks much more difficult.

In fact, the authors contacted GPG before publicly releasing this exploit and the fix is in place:

Q9 How vulnerable is GnuPG now?

We have disclosed our attack to GnuPG developers under CVE-2013-4576, suggested suitable countermeasures, and worked with the developers to test them. New versions of GnuPG 1.x and of libgcrypt (which underlies GnuPG 2.x), containing these countermeasures and resisting our current key-extraction attack, were released concurrently with the first public posting of these results. Some of the effects we found (including RSA key distinguishability) remain present.

...

Q13: What countermeasures are available?

One obvious countermeasure is to use sound dampening equipment, [...]

Alternatively, one can employ algorithmic techniques to reduce the usefulness of the emanations to attacker. These techniques ensure the rough-scale behavior of the algorithm is independent of the inputs it receives; they usually carry some performance penalty, but are often already used to thwart other side-channel attacks. This is what we helped implement in GnuPG (see Q9).

Comment Re:$12 is cheap IF you account for all the costs (Score 2) 1146

Also, how many tons of mercury and lead MORE are we as a nation going to mine, refine, transport, and ultimately toss into the local landfill each year using these newer bulbs over the old style ones? Oops, I forgot I wasn't supposed to mention that.

A brochure sent out by my power company said the amount of mercury released due to burning more coal for powering incandescent bulbs is far greater that the amount of mercury used in a CFL that replaces them. Popular Mechanics agrees:

Each [CFL] bulb contains an average of 5 milligrams of mercury,

... Over the 7500-hour average range of one CFL, then, a plant will emit 13.16 mg of mercury to sustain a 75-watt incandescent bulb but only 3.51 mg of mercury to sustain a 20-watt CFL (the lightning equivalent of a 75-watt traditional bulb). Even if the mercury contained in a CFL was directly released into the atmosphere, an incandescent would still contribute 4.65 more milligrams of mercury into the environment over its lifetime.

Comment Re:Whoah there! (Score 2) 88

You can get away with perjury all you want because judges don't care [...]

That is only because you are an individual and not a corporation. We live in a feudal society where individuals are serfs and corporations are the lords and masters. The purpose of the courts now is to protect corporations from individuals. Crimes against serfs are usually not considered significant but if an uppity serf rebels against a corporation then there is hell to pay.

Comment Re:Evidence To The Contrary (Score 3, Informative) 70

Parent:

I think the postulated optical aids are really a less interesting part of all this. What makes his paintings start out aren't that they have lots of accurate detail - they do, but that's not that rare - but that they have very accurate color. The rooms look realistic because the color values are right: they all have the same lighting temperature, to remarkable accuracy.

FTFA:

[Tim Jenison] was in no rush. His R&D period lasted five years. He went to the Rijksmuseum in Amsterdam. "Looking at their Vermeers," he says, "I had an epiphany" -- the first of several. "The photographic tone is what jumped out at me. Why was Vermeer so realistic? Because he got the values right," meaning the color values.

The point of using an optical aid was to get the colors right.

Comment Re:Surrogate decisionmaking (Score 1) 961

[...] but letting a loved one literally die of starvation while you watch is a cruel legal reality.

For a different persecutive, please read this article by Helen Nearing: At The End Of A Good Life:

Came a day he said, "I think I'll go on water. Nothing more." From then on, for about ten days, he only had water. He was bed-ridden and had little strength but spoke with me daily. In the morning of August 24, 1983, two weeks after his 100th birthday, when it seemed he was slipping away, I sat beside him on his bed.

IMO this was the most peaceful and dignified death imaginable. This is the way I would like to go.

Comment It's still total bullshit (Score 4, Informative) 670

The US has more prisoners per capita and also more total prisoners than any other country on earth. This is a huge drag on the economy. Not only is there a massive cost for keeping all of these mostly non-violent people imprisoned, we are also deprived of their contribution to the economy. Locking someone up often destroys not just their life but the lives of their children and other family members.

Passing more laws against non-violent crimes to lock up more non-violent people is going full tilt in the WRONG DIRECTION!

FTFA:

"We apparently caught them between runs, so to speak, so this takes away one tool they have in their illegal trade. The law does help us and is on our side," says [Lt. Michael Combs with State Highway Patrol].

Lt. Combs is delusional if he thinks his "side" can possibly win their war on drugs. It is possible that outlawing secret compartments is a natural extension of the war on drugs but that just shows how idiotic and insane the war on drugs is. Even if they took away all of our remaining civil liberties, the war on drugs would still be unwinnable. How much more must the American people sacrifice for the sake of this unwinnable war?

OTOH, Mr. Gurley is lucky he was not pulled over in the state of New Mexico where at least two different people have been forced to undergo enemas, colonoscopies, and anal probing based on acting nervous after a routine traffic stop:

After Eckert was pulled over, a Deming police officer said that he saw Eckert "was avoiding eye contact with me," his "left hand began to shake," and he stood "erect (with) his legs together,"

We are wasting billions of dollars; we are destroying millions of lives; we are militarizing our civil police departments; we are trashing our civil liberties; and we are destroying at least one neighboring country all in the name of a war on drugs that is impossible to win. It is stupid, it is sick, it is insane. It must stop.

Comment Fractal Cosmology (Score 0) 143

I first heard about the idea of Fractal cosmology in Mandelbrot's book from 1982, The Fractal Geometry of Nature. The idea is quite simple: there is structure at every scale in the Universe, at least up to some cutoff.

It is kind of funny that some people are surprised when structure is discovered at larger and larger scales as we are able to make observations at longer and longer distance scales. It is much more sensible to expect to see more structure as we see more of the Universe instead of the more common (and hubristic) expectation that we have already seen all the structure there is to see.

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