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NOTE: Since he has done extensive investigation into some implausibly hot temperatures reported in Death Valley, I asked Bill Reid to comment on my previous blog post where I maintain that the world record 134 deg. F highest recorded air temperature was likely biased warm by about 10 deg., and should not be accepted as a world record. What follows are Bill’s initial thoughts on the subject. Also, based upon his comments, I will likely update the charts found in my previous blog post with more realistic temperature lapse rate values in the early 20th Century when insufficient stations were available to determine accurate lapse rates.
by William T. Reid
A big thank you to Dr. Spencer for investigating the current (very dubious) world high-temperature record and for bringing attention to my Death Valley climate research. There are a handful of ways, both climatologically and meteorologically, to show that Greenland Ranch’s reported maximum of 134F on July 10, 1913, is likely not valid.
Dr. Spencer’s methodology here (comparing the Death Valley maximums to those the closest surrounding stations, with adjustments for station elevation) is indeed a devastating blow to the authenticity of the suspect observations. What it basically demonstrates is that the lower troposphere was not hot enough to support temperatures much above 125F in July, 1913. I have compared regional maximums for all of the hottest summertime events since 1911. In practically all instances (in which the Greenland Ranch and Death Valley reports appear reasonable), ALL of the maximums at the closest surrounding stations lend support to the maximums for Death Valley.
From July 7 to 14 of 1913, when eight consecutive afternoons had reported maximums of 127, 128, 129, 134, 129, 130, 131 and 127F in Death Valley, NONE of the maximums from the closest surrounding stations supported the Greenland Ranch maximums! The departures from average for maximums for the hottest five-day stretch were about +4 to +8 at the closest stations, while maximums at Greenland Ranch were nearly 15 degrees F above the average for July. (see table)
Annual maximums at Greenland Ranch from 1911 to 1960 ranged from 120F to 127F, except for the 134F in 1913. If the reported maximums at Greenland Ranch in July, 1913, were authentic, then the maximums at the closest surrounding stations in that month would have been much higher than reported. In addition, numerous regional heat waves have been hotter than the one during the first half of July, 1913. Why have Death Valley maximums failed to exceed 130F in the interim when three days in July 1913 purportedly reached 134, 130 and 131F?
In his “bias” chart, Dr. Spencer notes the “substantial warm biases in the temperatures reported at Greenland Ranch in the first 10-15 years.” And, he mentions that the observer(s) may have been relying to some extent on thermometers other than the official instrumentation. I do think that the observer was comparing “household thermometer” readings with the official equipment on occasion from spring to summer of 1913. Higher readings off of the poorly-exposed thermometers near the ranch house and under the veranda were probably (and inappropriately) entered onto the official climate form. But, I have not uncovered much evidence of this particular type of deviation from standard observational procedures outside of 1913.
I would contend that the generally higher “bias” numbers from the early years comparably are due primarily to changes at the closest area weather stations which promoted cooler maximums early on and warmer maximums later. For example, two of the closest stations to Greenland Ranch in 1913 were Independence and Lone Pine, in Owens Valley. In 1913, Owens River water was diverted to Los Angeles, and the Owens Valley gradually dried up. Summer maximums increased as Owens Lake evaporated, irrigation was not possible and farmland was abandoned, and desert-like conditions developed. (Roy’s note: The early years had very few stations within 100 miles of Death Valley, and the temperature lapse rates I computed from those few stations appear to be biased as a result. I will correct this in a future blog post, and will provide what should be better estimates of average July daily maximum Death Valley temperatures.)
Also, in the early decades of the 20th century, thermometer shelters were (almost invariably) sited above grass. This resulted in very conservative (i.e., coolish) maximums at desert stations. Low humidities promoted cooling due to evapotranspiration effects. In the early decades of the 20th century, desert weather stations were generally in towns, amidst shade trees and lawns. The resulting maximum temperature reports were very conservative. By mid-century and thereafter, the town weather stations were more likely to be at the airport or at a municipal utility site, fire station or equipment yard. Grass cover and shade trees were usually absent at these locales. Today, desert weather stations in towns and cities are (almost invariably!) above bare ground.
You can imagine the difference in maximums between desert stations above oft-irrigated grass and those above bare ground. (Roy’s note: In my experience, unless the vegetation area is rather large, and there is almost no wind, a weather station’s daily maximum temperature will still be largely determined by air flowing from the larger-scale desert surroundings. But note… this is different from, say a poorly sited thermometer next to a brick wall or heat pump where hot air from an isolated source can elevate the daily maximum temperature recorded).
The Greenland Ranch station was originally sited above a patch of alfalfa grass, immediately adjacent to forty acres of cultivated and irrigated land.
It is my belief that the new observer in 1913 (Oscar Denton) was rather disillusioned with the conservative maximums from the official station above grass and next to the evaporatively-cooled farmland. I think he felt compelled to fudge the maximums upwards in 1913. Photographs of the Greenland Ranch weather station show that it was above bare ground by about 1920 (see example photo at top of post).
I think that increased drainage is as important as anything else on tMax (and tMin) temperatures.
Emissivity 0.61 for the Earth as a Greybody, Rather Than a Blackbody
https://www.youtube.com/watch?v=RnA-KyjlD9o
RLH
I am sad for you that you posted such a bad video. This guy is awful because he is intentionally deceiving ignorant people who can’t research on their own.
He does not understand what the Greenhouse effect is and think it is a separate heat source. Shows how deceptive he is. I think he peddles this false narrative to people who do not know science but he makes them feel smart.
Here RLH.
https://www.researchgate.net/figure/Emissivity-values-for-the-land-cover-classes-used-in-this-study_tbl1_332571965
https://www.thermoworks.com/emissivity-table/?srsltid=AfmBOooeKmF0-9V2QEsu2leXwH8xCre5f5Tt_9_SWLK8QJ4dk26CJQfz
The charts in both these links show the video is terrible science. Water has an IR emissivity of 0.95.
Grass, dirt, desert and forest all have high emissivities. Please out of respect for your intelligence do not link to this person any more.
*** Yes! What Norman said! –Roy
What colour of grey would you give for the blue/green/yellow/white marble of our planet then? It is not black (except at night)!
This
https://en.wikipedia.org/wiki/The_Blue_Marble
RLH
I do hope you know the difference between reflected and emitted EMR.
The emitted radiation from Earth’s surface is in the IR band. Visible light is not emitted from the surface, it is reflected. So much different in concept.
You video is really bad. You can read up on emissivity and what it means and why this character is so bad. It is up to you. If you want to believe what he says then shame on you. If you read up on it and educate yourself you will see how bad this character is in deceiving the ignorant.
The emitted energy from Earth’s surface is near what an IR blackbody would emit.
“I do hope you know the difference between reflected and emitted EMR.”
I do.
However the reflected half is just as important. Afterall if it is reflected then it does not contribute to the heating of the planet. At all. Also IR is just a small part of the spectrum.
Do you agree that the planet looks like a grey body in the light of the Sun?
What percent is the coverage of clouds? On average. They are white (i.e they reflect quite well). As well as snow/ice. Also white. That alone means the reflective body is not black.
RLH
It is already known that the Earth reflects Sunlight reaching it.
It is already taken into consideration with the Greenhouse effect.
You are deviating from the horrible science presented in your video. He mentioned albedo and then he went to some terrible calculation to show that the Earth’s emissivity was 0.61 based upon complete flawed logic.
IR is the major band the Earth emits in so it is quite important.
When they refer to Earth as a near blackbody they are talking about it as an emitter. It emits between 90-95% as a blackbody would at the same temperature.
They are not saying the Earth is a total blackbody that absorbs all radiant energy. They are talking about its emitting as a blackbody.
“It is already known that the Earth reflects Sunlight reaching it.
It is already taken into consideration with the Greenhouse effect.”
Visible light is what the Sun emits. It is reflected quite well by the Earth. It does not contribute to the heating of the planet. What proportion of the Earth is covered by clouds? They reflect quite well.
“They are not saying the Earth is a total blackbody that absorbs all radiant energy. They are talking about its emitting as a blackbody.
We are only interested in the total (to do the calculations) not just the emitted spectrum (which as you acknowledge ) is only in the IR.
RLH
They have already taken the Earth’s reflection out of the equilibrium energy balance! They use 240 W/m^2 as the amount every square meter of Earth’s surface would receive if all the solar energy were spread out uniformly. It would be 340 W/m^2 without taking the albedo in consideration.
Basically you are just diverting away from the clear fact you posted a very anti-science video. Maybe just admit that the person in your video is a deceptive person that intentionally misleads (since he knows better but does not care) and move on.
Norman you have answered none of my questions. Particularly about clouds.
Norman. So you think the the Sun’s radiative power is 340*2 W/m^2 in space next to the Earth in its orbit? Assuming you believe that only 50% of the Earth is illuminated at any one time.
Hold on just a second Norman. Every time someone brings up the emissivity of Earth, someone like you links to the emissivity charts and says, look at water. Water has an emissivity of 0.95 and the Earth is 70% water, so the Earth’s emissivity is 0.95. I say BS! You don’t know what the Earth’s emissivity is. We know it is less than 1. Asphalt is 0.95. It has to be less than asphalt. Cement (calcium carbonate) is 0.5. I say it is somewhere between 0.95 and 0.50. Look at the comparison of the black body and gray body emission curves. Gray bodies, depending on wavelength and temperature are somewhat less than black bodies. Maybe the physicist’s thinking isn’t all that unreasonable.
Also, read about the black body theory. It is a uniform black body at thermal equilibrium. I don’t know if you can treat a planet with an ocean on its surface as a uniform black body.
One other thing, what seems more reasonable to you? Scientific assumptions need to make some sense. That the Earth’s emissivity is much lower than what we think or that 0.4% of the Earth’s gases cause 60F of warming? Which is more plausible?
Norman, you state that the earth receives 240W/M2 at the surface. That is misleading to say the least. Surely it’s how much energy enters the whole system which includes the atmosphere. Why ignore the energy gained by the atmosphere?
It should be noted that under bright sun the surface is not in thermal equilibrium with the air immediately above; the measured temps may be substantially elevated at 2M and will not approach the adiabatic lapse rate until the altitude at which the convective regime becomes fully established. This changes at night when the surface approaches thermal equilibrium with the air above.
*** Yes, very true. The closer you get to the surface, the higher the air temperature will be. This is why a standard height (2 meters) is chosen for air temperature measurements. Since all of the stations in question follow this practice, the resulting plots are apples-to-apples comparisons. The Death Valley and higher-altitude stations will all have super-adiabatic lapse rates in the lower several hundred meters by late afternoon. This is routinely seen in radiosonde (weather balloon) data in late afternoon (00 UTC) measurements in the SW U.S. –Roy
What can affect this spurious temperature elevation? Wind, rain, clouds, plant transpiration, quickly come to mind.
… surface albedo.
Interesting you say 2 meters for a temperature reading. I have seen the Stevenson screens in the UK in a few places and I can see the top of the so called white box. I’m not that tall.
So yet another indication that the data is biased. The fact that the boxes aren’t white would also bias the readings to the extremes.
Is there any reliable data?
The thermometer measures the instant temperature of the mercury in the bulb.
It is mostly influenced by the SW or IR radiation falling upon the thermometers body.
The gases around thermometer have very little influence on what thermometer shows on its display.
https://www.cristos-vournas.com
Wrong. Again.
Hallo Dr Spencer.I’ve been looking your site for more than ten years but never posted a comment, as I felt it was more for expert contributors. However as a Uk. citizen, traveller and congenital weather watcher since the 1960’s with experience in Africa and Australia, a personal experience in Western Australia is worth a mention. The farm where I used to work (inland some 200 mile north of Perth) lay not more than 50 miles from a small town called Eneabba. At the time I was there 1970’s it held the Australia record of 119F. The farm was on flat sandy plain and though I didn’t have a thermometer, there were days when it felt like that, particularly when working outside in full sun. My point in posting this was to suggest that temperatures in some parts of Australia like this can likely well match those recorded in Death Valley and it neighbouring stations. If any Australians contribute to your website, it might be an idea to ask them for details of the latest continental hotspots. Australians are known to be competitive and would doubtless be glad to knock Death Valley off the top spot. At the time I worked on the farm a pub in a town called Marble Bar in W.A claimed to have the longest bar in the world, 100ft if I recall right. It needed that to serve thirsty locals as Marble Bar also claimed to have had a summer season in which day temperature exceeded 100F for more than 3 months. Can Death Valley match that.
David L. Phillips
While preparing a comment about Death Valley and Oscar Denton’s alleged disillusion, I saw your hope in Australia beating the Californian hotspot.
Sorry for disappointing… Here is the top ten of a descending sort of all available daily temperature maxima in Australia:
ASN00076077 ___MILDURA_POST_OFFICE________ 1906 1 7 50.7
ASN00017043 ___OODNADATTA_AIRPORT_________ 1960 1 2 50.7
ASN00005017 ___ONSLOW_AIRPORT_____________ 2022 1 13 50.7
ASN00005008 ___MARDIE_____________________ 2022 1 13 50.5
ASN00005008 ___MARDIE_____________________ 1998 2 19 50.5
ASN00004090 ___ROEBOURNE_AERO_____________ 2022 1 13 50.5
ASN00017043 ___OODNADATTA_AIRPORT_________ 1960 1 3 50.3
ASN00076077 ___MILDURA_POST_OFFICE________ 1906 1 6 50.1
ASN00078077 ___WARRACKNABEAL_MUSEUM_______ 2018 1 19 50.0
ASN00018106 ___NULLARBOR__________________ 2019 12 19 49.9
Marble Bar’s top is a bit below with
ASN00004106 ___MARBLE_BAR_________________ 2023 12 30 49.3
By the way, you dont have to be afraid of ‘expert contributors’.
There are far fewer experts on this blog than opinionated,ignorant 360 degree deniers who endlessly claim that
– there is no such thing as time
– the existence of viruses has never been proven
– there is no GHE let alone any global warming except a ‘recovery from the LIA’
– like all planetary satellites, the Moon does not spin about its polar axis
– Darwin, Einstein and many others were all wrong
– the US NOAA uses only 1500 weather stations worldwide
– etc. etc.
The EM energy interaction process – instead of the simplified reflection + heat absorp.tion – the EM energy interaction process leads to a New, a complitely different the Planetary Surface Radiative Balance CONCEPT.
–
https://www.cristos-vournas.com
This article in Wunderground by Chistopher Burt appears to support your analysis. I just wish I could open the image files with pictures maps and data.
https://www.wunderground.com/blog/weatherhistorian/an-investigation-of-death-valleys-134f-world-temperature-record.html#:~:text=An%20Investigation%20of%20Death%20Valley's%20134%C2%B0F%20World%20Temperature%20Record,-By%3A%20Christopher%20C&text=In%202012%20the%20WMO%20(World,Libya%20on%20September%2013%2C%201922.
Burt asked me to write that article for his WU blog, and he helped with the writing and charts. I don’t know why the images were taken off, but you can find the entire articlel with the images on my web site, Jeff.
https://stormbruiser.com/chase/2022/07/12/an-investigation-of-death-valleys-134f-56-7c-world-temperature-record/
Additional info and charts for the July 1913 data in and around Death Valley are about halfway down this entry on my web site:
https://stormbruiser.com/chase/2019/02/22/unravelling-death-valleys-134f-temperature-record-part-4c-1911-to-1930-heat-events/
The Earths warming is because in the our times the winters are warmer, because at winters Earth is closer to the sun.
Link: https://www.cristos-vournas.com
The warming is faster now, because there are more free from ice waters at the North, the sea-ice cover is smaller.
Instead of being “consumed” as latent heat, the solar energy rises global temperature.
The Stefan-Boltzmann emission law cannot be applied to the EM energy /surface matter interaction process.
Therefore,
The Rotational Warming Phenomenon is not because of the non-linearity of the S-B emission law.
The Planet Rotational Warming is a much more Powerful Phenomenon.
–
Link: https://www.cristos-vournas.com
Please, do not capture CO2 from going into the atmosphere.
There is too little CO2 in the atmosphere. It is the plants food the CO2.
https://www.cristos-vournas.com
william…”You can imagine the difference in maximums between desert stations above oft-irrigated grass and those above bare ground”.
***
Yes…if the Stevenson screen is situated near a sprinkler system and a wind is blowing, the heated water vapour should penetrate the screen and affect the temperature recorded. As I recall, those thermometers have an indicator in the mercury vial that is pushed to a high and it remains their to indicate T max., after the mercury has subsided. Even if the record was a transient, it would be recorded as a max.
Also, it is normal for a human reading the thermometers to have a bad day and misread the thermometer. If it was me, I’d obsessively double- and triple-check the readings but on a bad day I might be careless.
We must e careful there, however. In 1977, global temperatures increase by 0.2C on average and some scientists wanted to write it off as an error. It was later discovered that the cause was the Pacific Decadal Oscillation, which had yet to e discovered.
There are many conditions in the atmosphere that no human can explain.
norman…”You video is really bad. You can read up on emissivity and what it means and why this character is so bad. It is up to you. If you want to believe what he says then shame on you”.
***
Norman…you are such a twit at times. Any scientist with whom you disagree is labeled by you as some kind of deranged being, hence wrong.
The scientist posted by RLH is a thoughtful guy who gives sound scientific reasons for his claims. His reasoning in the video in question is just as sound.
He points out correctly that blackbody theory is a theory developed out of desperation by scientists who had no idea how the EM radiation it is addressing interacted with matter. BB theory began circa 1850 with Kircheoff theorizing about science he could not begin to explain. In the day, it may have served a purpose but today it is so outdated it should e discarded as science.
There is no such thing as a blackbody and as the author of the video pointed out, we had to develop a system of emissivity to distinguish bodies that did not qualify as a blackbody, which was ascribed an emissivity of 1, from a BB. In other words, a BB is a perfect radiator and there is no scientific proof that this non-entity has such a property.
The irony is that the original S-B relationship between radiation frequency and temperature, by Stefan, did not reference a blackbody. It referenced only emissions from a heated body between about 500C and 1500C. Then Boltzmann brought his bag of theoretical statistical tricks to bear and conjured a blackbody environment that Planck adopted as the basis of his curve.
The author of the video is only pointing out the obvious: that the theorized temperature for a planet with no atmosphere or oceans as calculated using the THEORETICAL S-B equation is 255K whereas the measured average WITH an atmosphere and oceans is 33C higher. From that, it has been inferred that a mysterious greenhouse effect is responsible for the +33C warming.
The basis of this argument is shear pseudo-science for the following reasons…
1)some claim that GHE is due to trace gases in the atmosphere with not a shred of evidence presented to establish that claim scientifically. The proof is based on conjecture that a trace gas like CO2 can cause such warming based on theories from Tyndall and Arrhenius, neither of whom proved it worked like that in the atmosphere.
2)The 255K used as a baseline for the atmospheric warming cannot be corroborated scientifically, rather it is based on an anachronism created by Boltzmann that the radiation/temperature relationship can be calculated statistically and that it is a linear relationship, which it is not.
The real relationship between radiation and temperature, at all temperatures and conditions is far too complex to be relegated to a consensus-based theory from the 19th century, developed before Bohr came by the real relationship in 1913. Bohr’s relationship reveals the ineptness of BB theory and how a BB cannot meet the claims that it is a perfect absorber and radiator.
Look at the Sun, the closest we get to a real BB. Anyone who thinks it exchanges heat with Earth should be nominated for a Dumbbell Prize.
Gordon Robertson
You really do not know any real science so your rant is pointless.
If you had real science knowledge you would understand your lack of understanding. Since you do not have much real science and repeat things over and over it is not possible to reason with you.
The Stefan-Boltzmann Law is a Law because it applies to all types of experiments. It has been validated at cooler temperatures. You can validate it with the rate the Moon cools on its night side (they have recorded the temperatures you just have to use these in calculations to figure out the Stefan-Boltzmann Law works at colder temperatures.
The guy in the video is peddling false misleading science. He is bad!
The GHE is an insulating phenomena. The atmosphere acts as a radiant barrier lowering the amount of energy the surface will emit to space. This causes the temperature to rise from the same solar input. Any insulation will increase the temperature of a heated object. That you can’t understand this is no you.
“The GHE is an insulating phenomena. The atmosphere acts as a radiant barrier lowering the amount of energy the surface will emit to space”.
***
The GHE is based on a theory that presumes a trace gas can act as you have claimed above. The real science is that the heating phenomenon is due to all atmospheric gases absorbing heat from the surface and the Sun, hence delaying the balance of incoming solar to outgoing IR.
Calling that a greenhouse effect belies the action in a real greenhouse, where the rising air molecules heated at the surface are blocked by glass in a greenhouse.
The calculations in which S-B is used to determine a theoretical surface temperature for a planet without oceans or atmosphere is wrong. The notion that the planet is 33C warmer due to the effect of trace gases is equally wrong. That’s what the author of the video is claiming and he is right.
S-B was developed in two stages. In stage 1, which is correct, Stefan used an experiment by Tyndall to derive a T^4 relationship between the temperature of an electrically-heated platinum filament and the radiation it emits as visible light. The relationship applies only between about 500C and 1500C.
It is stage 2 that is controversial since it is based on statistical theory and not experiment.
Interpolating that T^4 relationship to terrestrial temperatures has ice radiating 315 w/m*2, which is absurd. That nonsense come from Stefan’s student Boltzmann who tried to work out, in stage 2, a statistical definition for energy and he was wrong. Unfortunately, there are far too many modern scientists who are stuck in that era circa 1880 and are completely unaware of Bohr’s 1913 theory that changed it all.
Of course, it seems you prefer out-dated science.
Gordon Robertson
You blab on about things you know nothing about. You make claims that ice does not emit some 300 W/m^2 at some near melting temperature but you have zero evidence to support it. You could prove you have science if you did some test on ice and monitored its cooling rate and see if it is emitting at such a rate. You make up nonsense you get off blogs and post it as it is fact.
You are oblivious to any Chemistry or path length.
Here read some real science instead of crappy blogs, you are very gullible to contrarian frauds!
https://en.wikipedia.org/wiki/Beer%E2%80%93Lambert_law
The GHG in the atmosphere are trace gases but have very long path lengths. All the IR emitted by the surface is absorbed and reemitted by these gases in the bands that they absorb.
I would prefer some real science from you and not the blog version and fraud.
norman…as Linus Pauling said when asked why he had not supplied a control on a study, why should I supply a control when the outcome is so obvious?
315 w/m^2 is a relatively significant amount of power, it’s akin to having 3 x 100 watt light bulbs radiating over a square metre. It’s enough to keep baby chicks alive in a brooder. Do you think that replacing the light bulbs with ice would keep them alive?
gordon, you’re showing your incompetence, again.
300 W/m² is nothing like three 100W lightbulbs. An incandescent bulb filament is emitting at a temperature over 2000F.
At least Norman has a “wiki” level understanding of physics. You understand none of it.
noun
skeptic
a person inclined to question or doubt accepted opinions:
“this argument failed to convince the sceptics”
christos…I think John Christy of UAH once wrote that skepticism is the hallmark of science. Without skepticism, science would be pointless.
The anti-science type of today are trying hard to discredit skeptics.
Has anyone fixed this blog yet?
FANTASTIC?
I thought it was fixed but you showed up again. 🙂 🙂
I’M JUST KIDDING!!! Good to see you’re back.
La Niña is playing games.
https://postimg.cc/06gFz93b
clint…”300 W/m is nothing like three 100W lightbulbs. An incandescent bulb filament is emitting at a temperature over 2000F”.
***
Clint…glad you finally figured out how to get past the Cloudfront issue that is preventing many people from posting. It’s good to have you back so I can correct your misinformation about matters like radiation.
For one, the power rating of a 100 watt light bulb is entirely related to the consumption of the electrical filament. Most of that power is lost as heat in the bulb itself. The actual EM power emitted from the filament is about 5% or 5 watts. Of course, that 5 watts is reduced by the inverse square law and the power dissipates as the square of the distance.
There is a good example of that here…
https://byjus.com/question-answer/about-5-of-the-power-of-a-100-w-light-bulb-is-converted-to-visible-2/
They calculate that the available power at 1 metre is about 0.4 watts/m^2. Before you flip out about radiation adding, I am not claiming that. However, we are interested in the effect that radiation has on a body WHEN IT IS ABSORBED. The individual radiation from 3 lamps will be 3 times the effect of of 1 lamp WHEN THE RADIATION FROM THE 3 IS ABSORBED.
So, if the wattage from one lamp at 1 metre is 0.4 w/m^2, the total effect of 3 lamps will be 3x that amount, and about 1.2 watts.
We are talking here of full spectrum EM radiation and not just the IR component. The IR component would be much less, yet it is is enough to keep the bodies of baby chickens alive when they are located a metre or so away.
The alarmists are claiming that any amount of ice can do the same, since ice is claimed to radiated at a power level of 315 w/m^2, which is sheer insanity.
That’s why I claim that the S-B equation does not apply at terrestrial temperatures.
bunch of recent posts have vanished