Sunday, September 11, 2016

Clarifying a Past Discussion on the Greenhouse Effect

Guest post by Bryan Killett

Dumb Scientist wrote this article in response to a comment Lonny Eachus recently left at the end of this conversation about the greenhouse effect and a solution to Dr. Spencer's thought experiment which helps demonstrate how CO2 keeps Venus warmer than Mercury.

Briefly: mainstream science says that adding CO2 warms Earth's surface, just like wrapping a blanket around a constant heat source in vacuum without them touching warms the heat source. The temperature increase after enclosing the source is exactly the same whether the surfaces are all treated as black bodies (which don't reflect radiation) or all treated as gray bodies (which can reflect radiation).
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... I will remind Bryan Killett, aka Dumb Scientist, what I've had to remind him of several times since in other media: my initial exchange with Appell was about a misunderstanding of whether Pierrehumbert meant NET flux or just SOME flux, in a passage from his book. However, Appell and Killett jumped on this, and decided to try to school me here on how thermodynamics works, based on an old argument I (as mentioned) had already changed my mind about. ... [Lonny Eachus, 2016-07-16]
Nonsense. Lonny "decided to try to school" yet another physicist by flooding Appell with Sky Dragon Slayer arguments. If Lonny really had "already changed" his mind, why did Lonny write all this in response to a single tweet?
@davidappell David, this claim has ZERO bearing on the physics of a MT hotspot "warming the surface". The physics are well-known. He states "The greenhouse effect shifts the planet's surface temperature by reducing the rate at which the planet loses energy at a given surface temperature." Which SOUNDS reasonable, but there is no physics behind it. The radiative power output at a given temperature is Area x (sigma x epsilon) x T^4, as described before. Atmosphere has no power to slow down this basic physics equation. As long as the atmosphere is COLDER than the surface, the surface will continue to radiate AT THE SAME RATE, until it in turn cools off. HEAT TRANSFER to other objects might vary... but the radiative power output associated with a given temperature remains the same. Atmosphere has no power to alter it. AND... I repeat: CO2 is NOT any kind of "insulating blanket", either. CO2 is a very efficient convective cooler... not an insulator. So I don't care what your "authority" says; he has his physics wrong. If forcing exists, that's not how it works. Let me give you a concrete example. You can do the math. Take a very big vacuum chamber (to keep it all radiative). Put a 1m^2 plate inside heated to 300°K. A meter away is a 10m^2 plate at 200°K. The radiative output of the hot plate is 1m^2 x εσ(T4). (We're assuming no reflection, and same emissivity for all materials.) The time for the hot plate to cool to 280°K is measured. Now... same setup, but you put a 275° plate near the 300° plate. How long will it take for the 300° plate to cool to 280°? The answer is: THE SAME. Because the other plate doesn't have any power to magically "reach out" and alter the radiative output of the 300° plate! The temp. starts the same and the radiative output will follow the same curve as before. AS LONG AS the other plate is colder. Further, since the other plate is colder, 1st & 2nd laws of thermodynamics say they can give no NET energy to the warmer plate. So there is no mechanism by which the colder object can warm (or keep warmer) the hotter object, RADIATIVELY. [Lonny Eachus, 2015-04-07]
Lonny's incorrect Sky Dragon Slayer answer is "THE SAME" but mainstream physicists know that the 300K plate cools slower if the 280K plate is near it. (Presuming that Lonny's vacuum chamber walls are colder than 280K.) If Lonny actually had solved the problem I'd solved for him, he'd have realized that his "discussion" with Appell was about Lonny repeating all that Slayer nonsense.
As I've explained to YOU, the discussion with Appell was about whether Pierrhumbert meant NET flux in a passage from his book. Yet you don't mention that anywhere here. Which, yet again, shows the dishonest purpose of your attacks. [Lonny Eachus, 2016-07-15]
Dishonest? Again, you were actually just repeating Sky Dragon Slayer nonsense in your "discussion" with Appell. In fact, screaming the word "NET" in ALL CAPS while pretending(?) to be hopelessly confused about its definition is one of your Sky Dragon Slayer behavior patterns that I've repeatedly mentioned. So is this:
@davidappell ... I repeat: CO2 is NOT any kind of "insulating blanket", either. CO2 is a very efficient convective cooler... not an insulator. So I don't care what your "authority" says; he has his physics wrong. [Lonny Eachus, 2015-04-07]
Once again, CO2 is an insulator, not a "very efficient convective cooler". I've showed Lonny evidence that increasing CO2 warms the globe. If CO2 isn't an insulator but a "very efficient convective cooler" then why does increasing CO2 warm the globe?
Simplified: Earth emits IR. GHGs absorb upgoing IR, then reemit IR in random direction, some of it downward = warming. [David Appell]
A cooler gas does not radiatively warm an already warmer surface. Not by any physics I ever learned. [Lonny Eachus, 2015-04-08]
Nonsense, Lonny. I've repeatedly told you that the greenhouse effect disappears if the upper troposphere isn't colder than the surface. That's also what the US NAS says: "The strength of Earth's greenhouse effect depends on the fact that the temperature decreases with height in the troposphere, so that emission from water vapor and clouds in the colder upper troposphere is less than that from the surface."

The irony deepens because this fact implies there's a situation where increasing CO2 actually can cool (part of) the Earth's surface. This happens if the upper atmosphere is warmer than the surface. At 5:09 in Andrew Dessler's video he explains why this happens. There's also a real-world example in Schmithüsen et al. 2015:
How increasing CO2 leads to an increased negative greenhouse effect in Antarctica

CO2 is the strongest anthropogenic forcing agent for climate change since preindustrial times. Like other greenhouse gases, CO2 absorbs terrestrial surface radiation and causes emission from the atmosphere to space. As the surface is generally warmer than the atmosphere, the total long-wave emission to space is commonly less than the surface emission. However, this does not hold true for the high elevated areas of central Antarctica. For this region, the emission to space is higher than the surface emission; and the greenhouse effect of CO2 is around zero or even negative, which has not been discussed so far. We investigated this in detail and show that for central Antarctica an increase in CO2 concentration leads to an increased long-wave energy loss to space, which cools the Earth-atmosphere system. These findings for central Antarctica are in contrast to the general warming effect of increasing CO2.

... if the surface is colder than the atmosphere, the sign of the second term in equation (1) is negative. Consequently, the system loses more energy to space due to the presence of greenhouse gases. The GHE and the instantaneous radiative forcing turn negative. ... The TES results demonstrate that the yearly averages of GHETES being negative are unique to the Antarctic Plateau and nowhere else observed on the planet. This is due to the fact that Antarctica is the only region on Earth where the surface is frequently colder than the stratosphere. ...
So Lonny wasn't discussing "whether Pierrehumbert meant NET flux in a passage from his book" as much as he was getting the physics completely backwards by repeating Slayer talking points. CO2 isn't a "cooler" globally because increasing CO2 warms the globe. However, when the atmosphere is warmer than the surface, the greenhouse effect reverses and increasing CO2 cools that surface. It couldn't work any other way. Not by any physics I (or any other mainstream physicist) ever learned.

This is yet another reason why Lonny's comments about Antarctica are incredibly ironic.
Explain where the "slayer" comments are? I am not, never have been, one of them. So point out: where is the "slayer" comment on that page? [Lonny Eachus, 2016-07-15]
Right here:
Comparing greenhouse theory to "thicker blanket" is ignorance of the physics of how it's supposed to work. ... [A blanket works by] preventing convection and conduction. That is NOT how greenhouse effect works. ... A "blanket" does NOT block "thermal radiation". You don't know anything about this, do you? ... NORMAL blankets do not "block thermal radiation". That's just false. ... You don't know squat about this. [Lonny Eachus, 2016-04-16]
No, Robert Ellis was right: blankets block conduction, convection, AND thermal radiation. Once again, Jane/Lonny Eachus is (unintentionally?) echoing Joseph Postma's Slayer nonsense:
Slayer Double Victory ... A blanket is about preventing convection, and has nothing to do with radiation. ... both versions of the greenhouse effect are debunked. The blanket analogy where radiation from a cooler object slows emission from the warmer object is false, because you cannot "slow emission" from the warmer object, and originally, the cooler object doesn't transfer heat to the warmer object. ... The Slayers won... the Slayers are the victors. [Joseph Postma, 2016-02-26]
Contrast Lonny's and Postma's and Latour's claims with mainstream science from NASA: "A blanket around the Earth... A layer of greenhouse gases - primarily water vapor, and including much smaller amounts of carbon dioxide, methane and nitrous oxide - acts as a thermal blanket for the Earth, absorbing heat and warming the surface..."

And once again, chapter 3 of this NAS video says: "... As concentrations of heat-trapping greenhouse gases increase in the atmosphere, Earth's natural greenhouse effect is amplified, like having a thicker blanket, and surface temperatures slowly rise. ..."
Think of greenhouse gases like a blanket. The more we add to the atmosphere the thicker the blanket and the warmer it is under it. [Dr. Michael SanClements via @realscientists]
That's a very BAD analogy. Blankets prevent conduction and convection. They have nothing to do with radiative "warming". [Lonny Eachus, 2015-07-31]
No, blankets also have something to do with radiative warming. Imagine a constant heat source like a human body with a constant metabolism, or an electrical heater drawing constant electrical power, or a planet with a constant albedo in a circular orbit illuminated by constant sunlight. Now imagine this heat source is suspended in the vacuum of space so it can't lose heat via conduction or convection. Allow the heat source enough time to reach a steady temperature T1.

Now wrap a blanket around the heat source without them touching. Again, allow the heat source to reach a new steady temperature T2. Unless the "blanket" is somehow completely transparent to the (probably infrared) radiation emitted by the heat source, T2 will be hotter than T1. For instance, under these conditions T1 = 150°F and T2 = 234.1°F. The blanket can't insulate the heat source via conduction or convection here. The blanket warms the heat source by blocking thermal radiation and radiating part of it back at the heat source.
How does colder insulation make a house warmer? [David Appell]
It doesn't. Insulation PREVENTS COOLING by inhibiting conduction and convection. It has nothing to do with radiation. [Lonny Eachus, 2015-04-08]
No, Prof. Robert Brown already told Jane/Lonny: "... Some things he [Sky Dragon Slayer Joseph Olson] states are blatently [sic] silly -- the assertion that a "space blanket" (reflective mylar sheet) works by blocking convection instead of trapping radiation (it's both, but the human body loses heat primarily through radiation, a simple fact that can once again be directly photographed). ..."

The Sky Dragon Slayer CEO John O'Sullivan also rides the Slayer "blanket" hobby horse:
... the 'blanket' analogy of the GHE is nonsense. ... [Sky Dragon Slayer CEO John O'Sullivan, 2012-11-20]
... We even involved leading space scientists to refute Spencer's absurd notion that outer space was 'cold' and that our atmosphere keeps us 'warm' like a 'blanket.' Also, the notion that any gas can 'trap' heat is one of the most absurd 'explanation's offered by these pseudo scientists. ... [Sky Dragon Slayer CEO John O'Sullivan, 2013-03-15]
And hey: when someone says "heat-trapping", tell them they don't understand the physics. Because they don't. [Lonny Eachus, 2015-11-29]
Nonsense. Once again, Lonny Eachus and John O'Sullivan are wrong. NASA and the US NAS and the AIP and the AGU and UCAR and MIT (etc.) understand the physics when they say "heat-trapping".

Lonny continued to discuss "whether Pierrehumbert meant NET flux in a passage from his book" with David Appell by saying:
CO2 is NOT an "insulator". Mainstream climate scientists acknowledge that. Insulation is a failed analogy. [Lonny Eachus, 2015-04-08]
No, Sky Dragon Slayers like Postma, Latour, O'Sullivan and Olson object to the insulating blanket analogy used by mainstream scientists at NASA and the US NAS, etc. Ironically, Appell had just told Lonny about yet another mainstream scientist who uses the insulation analogy:
... So after 6 pages of "science", he tells us WRONGLY that CO2 acts like a "blanket" or a reflector? Really? Here's the kicker: He writes: "Hot as Venus is, it would become still hotter if one added CO2 to its atmosphere." Venus' atmosphere is 96% CO2. So I have no choice but to presume this Pierrehumbert paper is a joke. I won't even bother to pick apart the rest. ... [Lonny Eachus, 2015-04-07]
Nonsense, Lonny. That Pierrehumbert paper isn't a joke. It's yet another example of a mainstream scientist debunking Slayer nonsense by CORRECTLY explaining that "carbon dioxide is just planetary insulation."

Lonny falsely claims Pierrehumbert's paper is a joke because Venus' atmosphere is 96% CO2. But even if it were 100% CO2, Venus would become still hotter if one added CO2 to its atmosphere. That's because the total mass of atmospheric CO2 would increase, raising the effective radiating level even higher, further insulating the surface. Ironically, this is yet another way to see that Lonny's "saturation" argument is wrong.

Slayers make a similar mistake when they claim that the Martian atmosphere's ~95% CO2 is making it "non-hot". However, the strength of a planet's greenhouse effect is set by its effective radiating level height, which is controlled by the total mass of atmospheric CO2, not its percentage. I've explained that since the Martian atmosphere is very thin, the total mass of Martian CO2 is much lower than the total mass of Venusian CO2. I've also shown Jane/Lonny this LASP link which explains how the small mass of Martian CO2 is responsible for its ~5°C greenhouse effect.
... Tc can never cause Th to be Th+anything. Ergo no GHG warming. [ASKirkpatrick]
We're in front of a fire - the sun; but our radiation doesn't make sun hotter. Heat flows H to C, no excep [ASKirkpatrick]
NET heat flows H to C. Radiation shields make thermocouples hotter: Daniels 1968 [DumbSci]
As usual, what he says here may have some truth but is highly misleading. On the second page of his lined paper, item 2, it says very clearly that the most important factor in radiation shielding of thermocouples is radiative transfer TO the thermocouple from outside sources. While surrounding a thermocouple with shielding MAY make it warmer, that effect is almost certiainly due to reflection. Or at least mostly. But core AGW theory has little to do with reflection. It's about absorption and re-emittance. [Lonny Eachus, 2016-07-16]
Nonsense. I repeatedly gave Lonny links to Daniels 1968 because thermocouple radiation shields can be analyzed using the same solution I'd already given Lonny. The temperature increase after enclosing the source/thermocouple is exactly the same whether the surfaces are all treated as black bodies (which don't reflect radiation) or all treated as gray bodies (which can reflect radiation). I've even specifically told Lonny that "my black and gray body calculations yielded identical enclosed steady-state temperatures".

So surrounding a thermocouple with shielding really DOES make it warmer, and under these conditions that temperature increase is completely independent of the presence or absence of reflections. Lonny's claim is incorrect.
[A rock at night radiating its daytime heat] cools slower if covered by a blanket because of conduction, convection AND radiation. [DumbSci]
Not unless it's a low-emissivity or reflective blanket. [Lonny Eachus, 2016-07-15]
Unless you're talking about a low-emissivity or reflective blanket, which is NOT what most people mean when they say "blanket". They mean a comforter. [Lonny Eachus, 2016-07-15]
Nonsense. The temperature increase after enclosing the source/thermocouple is exactly the same whether the surfaces are all treated as black bodies (which don't reflect radiation) or all treated as gray bodies (which can reflect radiation). Seriously: covering a hot rock with a black body comforter (without reflections) makes it cool slower because of conduction, convection and radiation.
Also, blankets block thermal radiation in addition to the conduction/convection effects. [DumbSci]
Out of context. Blankets don't "block" thermal radiation. They radiate it back out. [Lonny Eachus, 2016-07-15]
Nonsense. Blankets block thermal radiation by absorbing it, then radiating part of it back at the object or person surrounded by the blanket. That's the radiative part of how blankets insulate us, and how adding blankets WARMS us. Note that "block" isn't a synonym for "reflect".
... But core AGW theory has little to do with reflection. It's about absorption and re-emittance. [Lonny Eachus, 2016-07-16]
Just like blankets. That's why mainstream scientists use the blanket analogy even though Sky Dragon Slayers keep objecting to it.
Out of context again. The back radiation does not WARM. It prevents cooling. [Lonny Eachus, 2016-07-15]
Wrong, Lonny. Of course back radiation warms! Enclosing the 150°F source/thermocouple with a radiation shield/blanket WARMS it to 234.1°F. And once again, adding CO2 to the atmosphere WARMS the surface via back-radiation.
The simple fact is, Appell tried to claim a dynamic system, actively heated at one end and actively cooled at the other, was in "thermal equilibrium". As far as I was concerned, that was the end of "rational discussion", and I left. [Lonny Eachus, 2016-07-15]
Once again, I repeatedly told you that Appell and I were using the same definition of "equilibrium" (no change with time) used here by LASP to describe the Earth. So did Prof. Denning. In fact, Lonny himself has used the term "Equilibrium Climate Sensitivity" (ECS) many times. Even though the Earth is being actively heated at one end by the Sun and actively cooled at the poles and the nightside. Is that the end of "rational discussion" with LASP, Prof. Denning and Lonny Eachus?

I've also showed Lonny the same definition being used in Dr. Spencer's original thought experiment: "Eventually the second plate will also reach a state of equilibrium, where its average temperature (let's say 100 deg. F) stays constant with time."

And while solving a similar thought experiment that's actively heated and cooled at different ends, Prof. Steve Carson used "equilibrium" and "steady state" interchangeably: "What is the equation for the equilibrium surface temperature of the sphere, Ta? ... This is a "find the equilibrium" problem. ... Steady state means temperatures have stabilized and so energy in = energy out. ... its equilibrium temperature must be determined by P ..."
No, I'm telling you that your STATED objection to Appell also applies to many scientists [DumbSci]
... who would say steady-state is equivalent to equilibrium. [Lonny Eachus, 2016-07-15]
Yes, those terms are used interchangeably by many scientists. For instance, Lonny quoted a page written by Dr. Stephen O. Nelson where he explicitly states that "steady state = equilibrium". So Lonny's stated objection to Appell also applies to many other scientists, including the scientist Lonny quotes to "support" his argument!

Let's review again: conservation of energy says that power going in through some boundary minus the power going out equals the rate at which energy inside that boundary changes (dE/dt).

power in - power out = dE/dt      (Equation 1)

If nothing inside that boundary is changing with time, the rate at which energy inside the boundary changes (dE/dt) is zero.

power in - power out = 0            (Equation 2)

Physicists describe the situation in equation 2 as having no "net flow" of power through that boundary. Note that conservation of energy isn't specifically referring to heat flow because electricity flowing into the boundary still increases the energy inside the boundary even though electricity isn't heat.

Since all the temperatures calculated in this thought experiment aren't changing in time, they're all calculated using equation 2. Lonny's "confusion" regarding the label we use to describe "no change with time" simply isn't relevant because regardless of which label we choose, we still just use equation 2.

No, I'm telling you that your STATED objection to Appell also applies to many scientists [DumbSci]
But I also quoted one who disagrees. In thermal equilibrium, NO HEAT TRANSFER OCCURS. [Lonny Eachus, 2016-07-15]
Nonsense. Once again, you quoted Dr. Stephen O. Nelson saying that equilibrium is defined as "no net flow". He did not say "NO HEAT TRANSFER OCCURS". In fact, Dr. Nelson is simply repeating the explanation I've repeatedly given Lonny about the assumption behind equation 2: that there's no net flow of power through the boundary. There can be net heat transfer, as long as that outgoing net heat transfer equals the incoming electrical power. Which is true in this case.

Lonny: if you're right, why did Dr. Stephen O. Nelson explicitly state that "steady state = equilibrium" on the same page you quoted? Don't you see that he's just repeating the same physics principle I've been trying to explain to you?
... However, the discussion HERE never got past the stage of agreeing on initial conditions, because Appell would not even agree that a system that is being actively heated on one end, and actively cooled on the other, is not in thermal equilibrium. Why would I every try to discuss thermodynamics under such circumstances? With someone who won't even agree on something that simple, and even tries to label it a character flaw on my part for insisting on such a simple thing? It sure looked like a waste of time to me. ... [Lonny Eachus, 2016-07-16]
A few days ago, Dr. Guillem Anglada-Escudé announced (at ~27:50 into the press conference) that the newly discovered exoplanet Proxima b has an "equilibrium temperature" of ~235 K and used the term "equilibrium temperature" in Anglada-Escudé et al. 2016 (PDF). They did this even though Proxima b is likely tidally-locked to Proxima Centauri so it's being actively heated on the permanently illuminated hemisphere and actively cooled on the permanently dark hemisphere. In that case, why would Lonny Eachus ever try to discuss thermodynamics with the scientists who discovered the nearest potentially habitable exoplanet? It seems like that would look like a waste of time to Lonny.
Further, when I tried to simply establish that we were all agreeing on the nature of system being discussed, Appell repeatedly berated me for being "unscientific". [Lonny Eachus, 2016-07-15]
That's funny, the word "unscientific" doesn't appear anywhere in that "discussion". And the "nature of the system being discussed" was that it wasn't changing with time. You were pedantically arguing about the label used to describe "no change with time". Worse, you were being incorrectly pedantic by incorrectly lecturing physicists about physics terminology.
I told Appell I was leaving when he wouldn't agree there was no thermal equilibrium. [Lonny Eachus, 2016-07-16]
Let's temporarily overlook the fact that even the scientist Lonny quoted explicitly states that "steady state = equilibrium", rendering Lonny's argument self-contradictory and incoherent.

Instead, let's focus on the fact that David Appell told Lonny to call it whatever he wants and I've repeatedly told Lonny that I'll call the system in "steady state" when its temperatures don't change with time, in the naive hope that we might actually be able to finally take the very first step in this calculation.

So Lonny isn't just still being incorrectly pedantic and self-contradictory. Lonny's still being incorrectly pedantic and self-contradictory about a topic where several physicists had already magnanimously decided to let Lonny decide which label to use, in the naive hope that we might actually be able to finally take the very first step in this calculation.

Why would Lonny do that if he's not just frantically trying to avoid showing the solution he keeps saying he has?
You've spent several hours now claiming I should argue with somebody about heat transfer, but he wouldn't even agree on conditions that make transfer possible. [Lonny Eachus, 2016-07-15]
Nonsense, Lonny. I've spent several years now claiming that you're spreading Sky Dragon Slayer misinformation, and repeatedly explaining that you might be able to recognize that and finally stop if you'd just solve this thought experiment you've spent years wrongly lecturing physicists about. Instead, you keep frantically weaving a maze of words to avoid showing the solution you keep saying you have.
I have solved it on my own. Thanks very much. [Lonny Eachus, 2016-07-15]
That seems unlikely given the incorrect claims Lonny made above after claiming to have solved it on his own. Instead of just solving this thought experiment, Lonny has been frantically weaving a maze of words for years. Presumably to cover up the fact that Lonny can't correctly solve the simple thought experiment he's spent years wrongly lecturing physicists about. As part of his maze of words, Lonny has hurled other false accusations at me which I won't rebut in this article. Rebutting those accusations wouldn't be educational for anyone, and it wouldn't help Lonny finally find the courage to stop frantically weaving a maze of words and actually solve this simple physics problem.

3 comments:

EliRabett said...


One of the things you learn in studying thermodynamics is that the first step is to understand rates and the first misunderstanding of people like the Dragon Slayers is to not consider rates. Blankets, the greenhouse effect, etc. limit the rate of surface cooling. The consequence of this is that the equilibrium temperature of the surface increases as long as the sun still shines.

Oh yeah, on the blanket not cutting off radiation, how about survival blankets (aluminized sheets of mylar.

Dumb Scientist said...

EliRabett: "One of the things you learn in studying thermodynamics is that the first step is to understand rates and the first misunderstanding of people like the Dragon Slayers is to not consider rates. Blankets, the greenhouse effect, etc. limit the rate of surface cooling. The consequence of this is that the equilibrium temperature of the surface increases as long as the sun still shines."

I'm not sure that's the first misunderstanding of the Slayers, but it's certainly one of their first 100 misunderstandings.

Also, when talking with Slayers you might want to avoid using the word "equilibrium" the way scientists use it. As you'll note above, Lonny keeps insisting that the word "equilibrium" doesn't apply in these situations and keeps using this flimsy excuse to avoid showing the solution he keeps claiming he has. He keeps doing this despite the fact that Lonny also keeps referring to a page written by Dr. Stephen O. Nelson where he explicitly states that "steady state = equilibrium".

EliRabett: "Oh yeah, on the blanket not cutting off radiation, how about survival blankets (aluminized sheets of mylar."

Reflectivity doesn't matter, because "block" isn't a synonym for "reflect". After enclosing a constant heat source with a blanket, the steady state temperature increase is exactly the same whether the surfaces are all treated as black bodies (which don't reflect radiation) or all treated as gray bodies (which can reflect radiation).

Dumb Scientist said...

Lonny Eachus "responded" by flooding me with 202 tweets. As expected, he didn't show the solution he said he has, nor did he retract his accusations.