Pilot video for a series: Bill Scientific – "The Greenhouse Effect"

Guest post by Bill DiPuccio, Science Teacher

Let’s face it, high school science videos can be boring and ineffective. I like my science with a twist of comic exaggeration. So I decided to produce a video with enough humor to keep the students awake, and enough depth to challenge them intellectually.

This 30 minute video on the Greenhouse Effect is the prototype for a possible new series: “Bill Scientific” (I gave it a personal imprint to infuse some warmth and presence). Unlike introductory videos which attempt to cover a broad field of knowledge in a short time, the goal of this prospective series is to drill down into specific, but pivotal, topics in the physical and earth sciences.

Rather than just spooning out information, each program would be designed around experiments (the simpler the better) that can be used to illuminate and verify crucial scientific principles. Students will see science in action and gain a better grasp of the empirical basis for scientific theories.

Of course, future programs will depend on the response from students, educators, and scientists, as well as securing funding. The “Greenhouse Effect” was shot and produced on amateur equipment and software. Despite these limitations, I believe the final product faithfully conveys the intent of series.

 

P.S. If you like the video, pass it on!

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Leonard Weinstein

The idea of a video of this type is good, but the science presented is wrong, and would add to bad thinking. I only make a few comments, but much more is possible:
1) The atmosphere does redistribute the solar energy to prevent hot and cold from being as extreme as possible, but this alone is not a greenhouse effect, only storage and convection (also aided by ocean currents).
2) The Moon turns much slower than Earth to the Sun, so extreme surface heat and cold (in vacuum) are made worse by longer accumulation times.
3) The greenhous effect of actual greenhouses is caused mainly by the physical barrier of the surface trapping warm air, not just trapped long wave re radiation. The atmosphere has no physical barrier to free convection, so is different.
4) The Earth’s greenhouse effect is caused by longwave radiation partial insulation combined with the lapse rate of the atmosphere (due to air pressure drop with altitude). The longwave partial insulation moves the average location of radiation to space to higher altitude, locking the average temperature of the atmosphere at that average altitude.

Mydogsgotnonose

Make certain when you do the ‘PET bottle’ experiment, which purports to show the GHE with CO2, that you don’t use the PET bottle in the first place.
This is because most of the warming is from the increase of pressure AND the `indirect thermalisation of the pseudo-scattered IR at the bottle walls.
So, use a Mylar balloon like Nahle has,except you need to use a different thermometer than he used [an IR pyrometer which is optical depth dependent].
I think you’ll find there is no detectable direct thermalisation so the GHG-AGW effect is bunkum!

Still waiting for an explanation, why 6,000 ppm CO2 on Mars does not exhibit any measurable effect on theoretical vs practical temperature. Those 6,000 ppm should have the same overall “GH effect” as 400 ppm CO2 + thousands ppm H2O (g) here.
Oh, and the “+33K” is plain wrong.

It stopped just when it was getting interesting! And it would have been carbon monoxide that made Bill pass out from inhalation of exhaust fumes, not CO2.

Robbie

It looks like part 2 and 3 were too difficult for this website. (LOL)
Nice videos. I liked them.

LeeHarvey

I’ll apologize in advance – I swear I don’t mean this as an insult:
When I read ‘Bill Scientific’, the first thought to come to me was of Bill Nye.

polistra

Lively and Beakman-ish.
Two quibbles:
The intro seems a bit cluttered. Maybe start where Rebecca says “Are you sure you know what you’re doing?”
Maybe more emphasis on the experimental parts (the car as greenhouse) and the sensory parts (you can feel that with your feet).

Philip Bradley

I’m afraid you made a serious scientific error at the begining. The reason the Earth doesn’t have the diurnal range of the Moon is the thermal capacity of the Earth’s atmosphere and to some degree the thermal capacity of the Earth’s oceans. Although you can’t really separate the two.
Otherwise, not bad, although you introduce terminology without explaining the terms.

Brianp

Not bad the end needs a bit more work

MangoChutney

Maybe it’s me, but I prefer my science more like the style Brian Cox, his boyish enthusiasm and knowledge is moreish and how many other Professors can list 9 top 40 UK hits on his CV?

Owen in GA

Nice project. There may be mixed reviews in a classroom setting as some kids like the cheesy jokes and some will be turned off by it. It does convey the information though, so maybe it will hold their attention enough for them to pick up some of the basics of the atmospheric energy resistance in the IR spectrum (ok, we call it the greenhouse effect.)

Jer0me

Liked it very much!
The ending was a bit abrupt. I think that could have been spread out a bit. Very impressive overall, though!

adolfogiurfa

There is no lid on earth, that´s the difference.

Crispin in Waterloo

2% of 5% = 0.1% of the greenhouse effect caused by humanity’s fossil fuel combustion
Nice to see some facts presented for a change instead of hype. Loved the line about the glass sphere around the world. A lot of people really think there is some kind of sphere of CO2 ‘up there’ for which we are responsible. With ignorance-as-fact promoted by ‘An Inconvenient Truth’ abounding I will take Bill Scientific hands down over Suzuki as a source of knowledge.
CBC, are you listening? (Can you improve their accents?)

I like it

Dave in Delaware

Watched all 3 parts – not bad – author stays away from the politics (mostly).
I had to pick out the links for parts 2 and 3 from the list. here are the YouTube web links:
Part 1

Part 2

Part 3

Dave in Delaware

Unfortunate that the author is named Bill – He chose the name Bill Scientific for these reasonable links. He could easily be confused with similarly named “Bill the (non)- Science Guy”, who has recently been more an advocate than a scientist.

Makes the standard error most naif folk do. See http://en.wikipedia.org/wiki/Greenhouse_effect#Real_greenhouses

Roger Abel

Could someone please show me the calculations, based on Radiative Heat Transfer, Thermodynamics and Quantum Chemistry/Spectroscopy, that shows the CO2 molecule to have the radiative properties and capacities to behave as stated under the temperature and pressure our atmosphere can provide for it? Responsible for 5 to 26% of the atmospheric thermostatic regulation of temperature??? Prove it to me please…
The 3 videos had a lot of positive and fun ways to explain things to Highscool students though… 🙂

AnotherPhilC

Very good presentation. Packs a lot into 30 minutes. Brian Cox would have taken at least nine hours to cover the same material. There would have been 30 minutes of Brian Cox gazing at one single cloud, and the BBC would have called that “Science”.

AnotherPhilC

I think the Thermo-Slayer types rushed to judgement without watching the 30 minutes series, which is why they were first to comment.

MangoChutney

@AnotherPhilC
LMAO, agreed

AnotherPhilC says:
April 27, 2012 at 6:48 am
“Brian Cox would have taken at least nine hours to cover the same material.”
That’s not true, he covers a lot in a fue minutes here. lol

mpaul

From the video: “…and clouds can push that number even higher”
The subject of clouds as a positive forcing is controversial.

Bill Illis

Really good Bill, that took a lot of time.
The part about clouds was very important because it is almost never discussed.
Here is the Modtran downwelling radiation in the Tropics when low cloud cover is present. A perfect blackbody – no CO2 lines, no methane lines, just a blackbody. Now how often is cloud cover is present. How does it change with differing heights and thickness of clouds.
http://img832.imageshack.us/img832/295/tropicalsurfupclouds2xc.gif

Russ in Houston

Roger Abel says:
April 27, 2012 at 6:43 am
Could someone please show me the calculations, based on Radiative Heat Transfer, Thermodynamics and Quantum Chemistry/Spectroscopy, that shows the CO2 molecule to have the radiative properties and capacities to behave as stated under the temperature and pressure our atmosphere can provide for it? Responsible for 5 to 26% of the atmospheric thermostatic regulation of temperature??? Prove it to me please…
No, Roger. No one will ever explain this or prove this. No matter how many time you ask.

Babsy

Roger Abel says:
April 27, 2012 at 6:43 am
I think there is plenty of work done already that shows the math. Doing experiments in a lab that confirms the model seems to be a bit harder to come up with. Just sayin’…
🙂

Mydogsgotnonose

Bill: downwelling radiation does not exist. it’s an artefact of a radiometer blocking the Prevost Exchange Energy from behind the detector. It measures Temperature x emissivity only. There can be no energy transfer [2nd Law].
This Meteorological mistake is the reason why climate science is mostly wrong. indeed, I can’t think of anything they have got right except temperature, And as for the IR from the Earth being S-B for a B-B in a vacuum, no professional engineer who actually measures such stuff, and I am one, agrees.
This is why the climate models exaggerate radiative heat transport by .10 times.

mkelly

wmconnolley says:
April 27, 2012 at 6:41 am
Makes the standard error most naif folk do. See
From your link: “In the greenhouse effect, rather than retaining (sensible) heat by physically preventing movement of the air, greenhouse gases act to warm the Earth by re-radiating some of the energy back towards the surface.”
Mr. Connolley please write a radiative heat transfer equation showing how this takes place between the surface of the earth and a molecule(s) of CO2. Please use 1 atm and 288 K. I have asked you before but never heard back. So I ask again.

Russ in Houston

Babsy says:
April 27, 2012 at 7:31 am
Got a link?

G. Karst

If only CAGW was about science and NOT a religious/political campaign. GK

RICH

If nitrogen and oxygen “absorb almost no radiation,” how are they warmed then?

J

I think the comments here are an interesting study on how subjective science and especially science education is. Subjective in the sense that when you are simplifying, the degree of simplification and the choices of what to leave out is underdetermined, even for a reasonably well-defined audience, and different choices will make more or less sense to the subject presenting the science. There may be factual errors–I’m not too worried about them. In the end, teaching the greenhouse effect is a lot more like teaching the civil war than most scientists (and probably historians) usually appreciate, which points to a breakdown of enlightenment notions of a strict dichotomy between purely subjective and purely objective. Real teaching involves the messiness involved here, regardless of the subject.

Russ in Houston

RICH says:
April 27, 2012 at 7:53 am
I would say that it is direct contact with the surface that just absorbed that incoming energy. Think about this – if you have a hot cup of coffee, what makes it cool down as it sits on your desk (beside your keyboard)? Without any scientific experiment I will bet a steak dinner that contact with the surrounding air has a much greater effect (x10) than IR emissions. Now, relate that to the world outside your window.

RICH says:> If nitrogen and oxygen “absorb almost no radiation,” how are they warmed then?
Std thermal exchange via collision.
mkelly says:> Mr. Connolley please write a radiative heat transfer equation… Please use 1 atm and 288 K
Dunno quite what you want; your question doesn’t really make sense as you’ve posed it. The std stuff is all available in the obvious places, most obviously http://en.wikipedia.org/wiki/Idealised_greenhouse_model If you want more details, then http://scienceofdoom.com/roadmap/atmospheric-radiation-and-the-greenhouse-effect/ is a good place to start. If you want to pretend that the GHE doesn’t exist, find someone else to talk to.

John from CA

Liked the videos, they have a human quality to them — a quality over produced broadcast videos lack. Consider using the initial video as a means to empower the students to add to the series. This would allow the topic and videos to evolve from their perspective. Students educating students — a one room school house approach that allows the videos to interrelate to other disciplines comes to mind.
This is a tall request. One of my pet peeves, aspects of the climate system are frequently discussed without a reference to the system as a whole. This over emphasizes the importance of the aspect and under emphasizes compensating factors and system relationships. The intro to each segment could illustrate the system and the aspect being discussed in the video segment.
Another intro video to the topic as a whole could discuss many of the terms that are being thrown around — roles you could have a lot of fun portraying. Terms like Affirmer (Warmer), Denier, Skeptic, Lukewarmer, Consensus, Settle Science come to mind.
See Lord May’s presentation for some glossary ideas.
The motto of the Royal Society is [s/b was]: Nullius in verba: on the word of no one
Science as Organized Skepticism by Lord May
http://downloads.royalsociety.org/audio/DM/DM2010_03/May.mp3

Mydogsgotnonose says:
April 27, 2012 at 7:33 am
Bill: downwelling radiation does not exist.

Bzzzzzt WRONG!
You may be able to peddle or push that nonsense over on the Bish site, but you’re being called on it here … ever heard of a field of science called IR Spectroscopy?
Do you understand how a bipolar molecule responds to EM energy?
.

I’ve posted this before; apologies beforehand to those who have seen it before, but this is the perspective an RF guy (Radio Frequency and radio engineer who works with and designs, and models antennas including the MOM – Method of Moments (NEC) and FEM – Finite Element Method (Ansoft HFSS) techniques) sees this all this:
The 12 easy steps to understanding the physics of the minor, but important, GHG effect.
1. The ‘motion’ of Electrons and Protons can be affected by externally applied electric and magnetic fields. Computer CRTs are an example with the electron beam forced towards the phosphor-coated screen by a more or less ‘static’ electric field all the while under the back and forth influence of a dynamic magnetic field from the deflection coils (called ‘the yoke’ in the trade).
2. Conversely, when Electrons or Protons move, they create ‘fields’ and then perhaps (propagated) ‘waves’ as well. Electromagnets and antennas are examples.
3. Molecules, such as CO2 and H20 are comprised of atoms the components of which are Protons and Electrons (we ignore the Neutron). This is elementary; consult any HS text for a refresh.
4. Many molecules such as O2 (and even CO2 and H2O) have specific mechanical resonances, at specific frequencies (or wavelengths if one prefers).
5. These mechanical resonances are like miniature tuning forks. The vibrational modes get a little intricate and differ from molecule to molecule on account of the ‘atomic relationship’ of the member atoms.
6. During these vibrational modes, certain ‘member’ atoms can move more than others, and some ‘parts’ are electrically charged … referring to 2. above this will create a ‘field’.
7. Should a particular frequency EM field pass by a resonant molecule, the molecule, like a resonant dipole antenna will ‘pick up’ (the field will induce into the molecule) energy from the passing field .. refer to 1. above.
8. The actual resonant frequencies of resonant molecules is affected by pressure; this means more collisions between atoms, and sometimes vibrational energy can be absorbed in a collision while sometimes energy is given off. ‘Broadening of spectral lines’ is the basic effect.
9. Any vibrational modes amount to ‘stored energy’,
10. Said ‘stored’ energy is also continually being re-radiated (refer to 2. above) in basically all directions (any given molecule will have a given radiation pattern, but in the aggregate among all randomly oriented molecules this yields an ‘omni’ directional pattern).
11. An increased amplitude ‘Vibrational mode’ (no matter how arrived at) amounts to a ‘higher temperature’ locally.
12. From insolation (incoming sunlight), to heating of the earth’s surface, some convective heating of the air near the surface (consult a meteorology text; the MAJORITY of the heating of the air is in the boundary layer), to radiation of LWIR from the earth’s surface, some LWIR is captured’ (excites or is EM induced into) various GHG molecules e.g. CO2 and H2O … and that ‘captured’ EM energy is re-radiated in all directions, *including, and this is very important: BACK to earth … some term this ‘back radiation’, perhaps after the close radio term, ‘back-scatter’ (as used in RADAR to identify energy ‘reflected’ or scattered back from a target).
And so there you have it.
The 12 easy steps to understanding the minor but important (as to moderating the surface temperature of the earth) GHG effect.
Added: How does this ultimately affects the climate and what the ‘sensitivity’ of the climate is to changes in CO2 levels? I’m going to kick this can down the road for the time being, but I don’t think there are any ‘tipping’ points that will be reached.
.

beesaman

Well the camera does love Brian Cox or is it the other way around?

Matt Schilling

wmconnolley thinks people who believe in something in which he does not believe, and for which he has disdain, should “find someone else to talk to”. Hmmm. That he comments here at all demonstrates he (correctly) assumes the rest of us don’t ascribe to his arrogant attitude.

The problem is that the greenhouse effect, per a glass greenhouse, does not exist in our atmosphere as a greenhouse specifically prevents convection, which is the entire reason a greenhouse warms. Glass lets IR out, so the glass of the greenhouse is actually a negative in keeping the greenhouse warm.
The IR absorbed and re-emitted by molecules in the atmosphere and sent downward hits a surface which is warmer than the atmosphere and must either exchange evenly with emitted radiation or resonate and reflect back. [The equivalent energy levels in the surface are full and the IR cannot be absorbed as new energy unless another IR is emitted leaving an empty energy level.] The downward IR CANNOT warm the surface, per the 2nd Law of Thermodynamics. The greenhouse effect, thus, does not exist as the atmosphere is free to convect warm moist air to altitude.
The Earth, as opposed to the models, has a nighttime during which IR bleeds to space. CO2 and water vapor also bleed energy as they convert heat energy to IR which also is lost to space. A bit of downward IR might impinge one the surface, but it is not clear which will cool faster, the air or the surface, but I’ll put money on the air cooling faster, given the heat conductivity of rock being slower than a gas. Thus, even at night, the atmosphere cannot warm the surface.
Nice video, but in my opinion it is a bit mis-informative.

Robert S

No mention of absorption to extinction for the wavelengths in question and the fact that because of this extinction no further absorption would take by adding more CO2.

Robert S

…would take place by adding more CO2. Also how is the distance to extinction calculated.

> wmconnolley says: April 27, 2012 at 6:41 am: Makes the standard error most naif folk do.
And on further consideration, I’m being too sniffy. It was the bit at 3:30 in the first video “since these waves are unable to pass through the glass”. They can’t, but that doesn’t much matter, and this has been known for ages (e.g. http://wmconnolley.org.uk/sci/wood_rw.1909.html), and the video corrects itself later.

tjfolkerts

J says: April 27, 2012 at 8:08 am
“I think the comments here are an interesting study on how subjective science and especially science education is. “
I would second that though. Two quotes come to mind:

“Everything should be made as simple as possible, but no simpler.”
(Attributed to Albert Einstein)
“Essentially, all models are wrong, but some are useful.”
George Block

“As simple as possible” is, of course, relative. To get the gist of the effect of IR absorbing gases, a simple explanation with a simple model suffices. No actual math is required.
To calculate actual heat flows (like some are asking for in this thread) requires a much more sophisticated model. The calculations for the exchange of IR photons between land and air and space for this model are not simple. This level of detail cannot be adequately be explained or expressed in a 3 paragraph reply to a blog. Frankly, anyone who asks to be tutored from a high school level understanding to understand a PhD-level analysis in a blog doesn’t understand how science works and doesn’t understand enough physics to even be asking the question. A better question would be something like “I made assumptions X & Y & Z, and calculated the heat transfer to be Q. Why does this disagree with the numbers presented in ABC”. Then at least others know the model and the assumptions, and can try to figure out the next level.
##################################
But back to the original video, I thought it was pretty good for the level it was aimed at. There were a few things I would have said differently (eg, the glass in a greenhouse doesn’t “reflect” the IR, but rather absorbs IR and then radiates its own IR due to its own temperature) but for a fun video aimed at a high school audience, I think the knowledge presented is both “useful” and “simple, but not too simple”.

steveta_uk

Higley7 said

A bit of downward IR might impinge one the surface, but it is not clear which will cool faster, the air or the surface, but I’ll put money on the air cooling faster, given the heat conductivity of rock being slower than a gas. Thus, even at night, the atmosphere cannot warm the surface.

I recall reading something from Roy Spenser where he pointed out that at certain times of year, frost was common on the ground, on your car, etc. when the air temp had not gone down to 0C.
And from his back-garden experiments, it is clear that solids can lose heat at night by IR much more easily that air (esp dry air).

John F. Hultquist

Jim @ 8:46 am
When you did previously post this explanation I meant to comment on its clarity and thank you – didn’t then; do now.
I have a question and a suggestion. A link to images of molecules that suggest how they react (or don’t react — See wmconnolley’s terse response @8:10 am to Rich) would help.
The question is: You use the terms ‘captured’ and re-radiated. Single quotes yours, but not also on re-radiated. You seem to be suggesting something with ‘captured’ — What? And is it not so that what comes back, that is, re-radiated, is not equivalent to what goes in. The “re-” part seems to say that it is. If what comes out isn’t exactly the same as what goes in then “re-radiated” confuses the process. Hope this question makes sense.

Russ in Houston

_Jim says:
April 27, 2012 at 8:46 am
Thanks Jim
Your explanation makes great sense…but you kinda lost me at number 11. Converting vibration to temperature? Do you have an equation for that?

John F. Hultquist

steveta_uk says:
April 27, 2012 at 9:24 am “Roy Spenser”
!! Spencer
http://www.drroyspencer.com/2010/07/experiment-to-test-the-temperature-influence-of-infrared-sky-radiation/
In a comment, Mark P., uses “frost on the ground” in the manner you suggest.

I watched the first one. Plus points for being cheerful when there are so many scary and solemn (and, I would add, reprehensible) materials clearly intended to scare children about climate. The undue emphasis given to CO2 in the video is the same ‘mistake’ as committed by such as the IPCC. I put the word in quotes since of course it was a deliberate one. The failure to note the early 20th century experiments on the greenhouse effect in real greenhouse-like structures is a bit odd since they showed the essential irrelevance of the infra-red properties of glass. These experiments have been repeated more recently, and would surely be feasible to set up for use in high schools. The name ‘greenhouse effect’ has had such an appeal for its emotive effect (well exploited for political and financial purposes by many) that it will be hard to discard it, but it ought to be discarded with regard to the atmosphere. Alternative names include ‘Tyndall gases’ for those active in the infra-red, and even the ‘Tyndall effect’ for reference to their role in the climate system, thereby recognising a pioneer of careful measurment in this area. (No scary associations of sweating and discomfort or even death in a closed car or sealed greenhouse, so not so good for campaigners intent on spreading fear). I think the attention towards the end given to the water cycle is promising. The water molecule is so important in our climate system that a marvellous course of materials for high schools could be created around it, and CO2 would be relegated to the minor, mostly secondary role it deserves to have. For example, the climate system in recent decades has been behaving pretty much as it might if the extra CO2 was of negligible importance compared to other factors.
So well done for being cheerful and upbeat. We shall have great need of that once work gets underway to reverse the hideous scaremongering targeted on the young and other vulnerable groups (including many credulous adults). I’m looking forward to watching the other 2 in the series when I get a chance to do so.