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1 - Home experiment to illustrate the cooling power of latent heat.
#1
Hi All,
Some of you maybe aware that I say that "we" should always differentiate (particularly in our studies of earth's climate) between,
1) conduction and convection of sensible heat and
2) the convection of the latent heat of water vapourisation.

Generally at present "we" do not make such a distinction, I think "we" should, and always should do so,
as the following hopefully illustrates.

[Image: MUGS-sized.jpg]

I simply took two mugs and placed them on a chopping board.
I then put a little cooking oil in one mug, approximately 3mm depth, and
the same amount of room temperature water in the other mug.
I filled both mugs up with freshly boiled water from a kettle, and left them for 10 minutes.
The oil in the left mug above forms a layer on top of the water very quickly, which stops any water vapourisation latent heat losses from the "oily" mug.
The mug on the left in above photo is the "oily" mug, the photo having been taken about 25 minutes into the test.
There is no steam visible from the right hand, water only mug - but water is still being vapourised....
Hence the mug on the right, the water only mug, is constantly COOLER than the "oily" mug.

At first you can plainly see steam coming off the top of the water only mug,
the mug with cooking oil in does not steam at all, at any time, after the oil forms a top surface layer.

After 10 minutes, the side of the mug with oil in is warmer to the touch than the side of the mug with water only in it.
I repeated this touch temperature test every 10 minutes upto an hour and a half later.
Every time I tested the side of the mugs temperature with my finger tips the water only mug was COOLER to the touch.

I think it worth noting that both the mugs can both equally and easily radiate and conduct and convect sensible heat.
Infact, as the "oily" mug is warmer throughout the test than the water only mug, then,
the "oily" mug is radiating MORE thermal IR and conducting and convecting MORE sensible heat during the test than the water only mug.
YET,
the water only mug is COOLER, in comparison to the "oily" mug throughout the test.

WHY??

Also, I would note that, the sides, and top surface of the mugs and liquid are the available surface area for the emission of thermal IR , and,
the conduction and convection of sensible heat.
The latent heat of water vapourisation can only be lost from the water's far smaller surface area, in the water only mug.
YET,
The water only mug remains COOLER, right back down to room temperature.

WHY??

This "experiment" is to my mind a clear demonstration that,
the convection of the latent heat of water vapourisation is the most powerful cooling mechanism,
when compared to emission of thermal IR, and conduction and convection of sensible heat.

At present it is seemingly "accepted" and common practice that "conduction and convection" means both of sensible and the latent heat of water vapourisation.

WHY??

They are completely different "things".
It appears to me to be a misdirection.
A misdirection that could give one a false impression of reality, because as the above Derek's "oily" and water only mugs experiment shows,
the convection of the latent heat of water vapourisation is the most powerful cooling mechanism of the three in this example, and,
that this cooling mechanism works all the way down from boiling point to ambient room temperature, and
probably at any temperature above O degrees Celsius for fresh water, and above -1.8 degrees Celsius for salt water..

If there was any wind in the room then the difference would be even more dramatic,
which is why you blow on a hot cup of coffee, or tea, to cool it down quickly.
The whole aim of practical politics is to keep the populace alarmed
(and hence clamorous to be led to safety)
by menacing it with an endless series of hobgoblins, all of them imaginary.

H. L. Mencken.  

The hobgoblins have to be imaginary so that
"they" can offer their solutions, not THE solutions.
Reply
#2
Nice one Derek. Easy demonstration for the doubtful neighbours.

I've argued before that evaporation removes more heat than "backradiation" can supply from a single infra-red radiation frequency. (clear skies at night of course Wink ) Problem is how to convince the dumbos who elect the nuckleheads that see a cornucopia of everlasting infinite tax income.

Tell you what. Do the experiment on youtube but add a couple of thermometers.
Environmentalism is based on lies and the lies reflect an agenda that regards humanity as the enemy of the Earth. - Alan Caruba
Reply
#3
THANK YOU Richard111.

(08-29-2011, 01:44 AM)Richard111 Wrote: Tell you what. Do the experiment on youtube but add a couple of thermometers.
Noted, I agree, but I wonder if we can develop it more yet.
Filmed outside on a still winters day, with, as Joe Olsen has (privately) suggested a coal fired power station's cooling towers as a backdrop.
AND, I'd do some simple over time plots of the temperature difference between the mugs.

I'd like to get to earth's surface is a refrigerator powered by solar AND geothermal input, probably about 65% / 35%, + or -15%.
Geysers are so hot, mountain streams are so cold...
Or, is that too much?

I was hoping you would pick up on this one Richard111. Smile
It was at least partially "inspired" by our hopefully ongoing discussions on this thread,
http://www.globalwarmingskeptics.info/fo...-1482.html
[split]Photons and MASS in calculations...Split from CO2 home experiment thread.
whilst I was watching The DaVinci Code on the tele last night.
AND,
I wish to express my sincere apologies and regrets to yourself, Richard111, for some OTT remarks I posted (and have since deleted) that were aimed at you,
which were due to my frustrations with others. That will not happen again.

Is there a way we can convert the above experiment to numbers?

Another thread for "new readers" that is worth remembering at this point is, in relation to what this simple experiment demonstrates, is,
http://www.globalwarmingskeptics.info/fo...efrigerant
Water is the refrigerant of the troposphere.

NB - I have, I think, sussed what was, or rather is, "wrong" with the various versions of the CO2 bottle experiment.
Why do they seem to give contradictory, unreliable, or in support of AGW results, when in fact they do not??
It is all in, water vapour, rigidly contained, and mass of the various versions I have been looking at.




The whole aim of practical politics is to keep the populace alarmed
(and hence clamorous to be led to safety)
by menacing it with an endless series of hobgoblins, all of them imaginary.

H. L. Mencken.  

The hobgoblins have to be imaginary so that
"they" can offer their solutions, not THE solutions.
Reply
#4
Nine years in the army gave me a pretty thick skin. Three years in a university taught me not to sound off on anything I don't understand. Wink

I limit my comments to my understanding of the science. I am not qualified to comment on anybody else's interpretation of the science. If I think they are pulling a fast one on a known law I might point it out.

Anyway, I'm a sucker for 'simple' experiments and I am currently in the process of sweet talking my wife into allowing me to buy TWO sugar thermometers. Big Grin

For another, rather more complex, home experiment, have a look at TALLBLOKE'S TALKSHOP Konrad: Empirical test of ocean cooling and back radiation theory

Basically, this experiment is to check how much heating is provided by back radiation into a quantity of water. Much more finesse here than my experiment a few months ago. Rolleyes

I get a lot of fun reading the comments on threads like this.
Environmentalism is based on lies and the lies reflect an agenda that regards humanity as the enemy of the Earth. - Alan Caruba
Reply
#5
Although I am not sure anyone understands all or most of "the science", I do see what you mean.

But, as there is no such thing as a dumb question...I'll raise a couple of things that occurred to me today.

1) The water vapour that is vapourised is at a certain temperature, as well as having some latent heat.
When the water in the mug is above the air temperature, it presumably means the water vapour also transports sensible heat, as well as latent heat.
So, water vapourisation increases sensible heat losses from the mug, and therefore
attributing the heat losses in the water only mug, only to latent heat losses is incorrect.
Water vapourisation, when the water is warmer than the air, is also transporting sensible heat.

2) I have been told that, technically speaking, water vapour at 100C is steam, below that it is water vapour.
But, one can see the water only mug steaming at first, and one can see a lake steaming on a cold winters morning?
Why is this "steam" (which is not steam technically speaking) visible, yet water vapour invisible?
Is it to do with the amount of sensible heat the "steam" is transporting, relative to the air it is in?

(08-30-2011, 10:29 AM)Richard111 Wrote: For another, rather more complex, home experiment, have a look at TALLBLOKE'S TALKSHOP Konrad: Empirical test of ocean cooling and back radiation theory

Basically, this experiment is to check how much heating is provided by back radiation into a quantity of water. Much more finesse here than my experiment a few months ago. Rolleyes

I get a lot of fun reading the comments on threads like this.

Interesting thread and experiment, thank you.

I particularly note this comment,
George W Nixon as short bloke says:
August 30, 2011 at 5:54 am

Yes Cementafriend, the understanding of the actual physical realities of the masked assimilation of heat energy in a change of state – liquid water to water vapour – is not well understood; how is the extra heat energy present in H2O vapour stored given that there is no increase in the rapidity of random motion of the vapour molecule? Presently the masked energy is supposed to result in unexplained motion within the molecule. Also, how and why does the return of that hidden heat energy within the molecule result in radiated energy with no change to the rapidity of the random motion of the combining molecules? There is a mystery here that does not have a satisfactory answer if heat energy results from the rapidity of the random motion of molecules.


I posted,
In Test B am I correct in reading that one "roof" is,
" I used an A4 sheet of 10mm Styrofoam with aluminium foil attached with spray adhesive. "
and the other roof is a,
" cling wrap sky. "

Would the two tanks of cooling water be differently "insulated", explaining the temperature difference,
rather than one "warmed" slightly by "backscattered LWIR"?



OH, BTW Richard111, I have not a clue why your iron plate warmed 3C just before dawn,
without any direct sunlight upon it.
Is that a "constant" thing, ie, did it happen every morning?
Reply
#6
Lots to learn here. Smile My understanding is it takes FIVE times the heat energy to vaporise a quantity of water as to heat it to boiling point. Where is that energy going? Is it released later? How?

As to the plate warming up before sunrise; I only noticed it ONCE! On the only clear morning during my experiment. Milford Haven is a very cloudy place. This morning was clear to the north at six am and my outside thermometer recorded 5.5C. The harbour site read 8C. I don't do 'outside' at these temps at my age. Big Grin

Quote:dlb says:
August 28, 2011 at 6:36 am
Richard 111, Roy spencer mentions something similar in a home made experiment. His insulated box started to heat at dawn even though there was no direct sunlight on it. I would imagine blue sky is scattered blue and UV light, plenty of energy there. http://www.drroyspencer.com/2010/07/firs...mperature/

I think I will try make up a little 'hotbox' and repeat the experiment. Be much easier to handle than than sheet steel. (sharp edges too!)

Don't hold out much hope of clear sky mornings at the moment. Winter looks like it is coming early this year.
Environmentalism is based on lies and the lies reflect an agenda that regards humanity as the enemy of the Earth. - Alan Caruba
Reply
#7
(08-30-2011, 10:53 PM)Richard111 Wrote: Lots to learn here. Smile

Errr, lots to be understood by anyone yet, I think might be nearer the reality of our "understanding" at present.

Have you seen the recent comment by tallbloke,

tallbloke says:
August 31, 2011 at 10:52 am

And more experimental evidence proving the holy bible of radiative transfer wrong:

Belmiloud, Djedjiga, Roland Schermaul, Kevin M. Smith, Nikolai F. Zobov, James W. Brault, Richard C. M. Learner, David A. Newnham, and Jonathan Tennyson, 2000.
New Studies of the Visible and Near-Infrared Absorption by Water Vapour and Some Problems with the HITRAN Database.
Geophysical Research Letters, Vol. 27, No 22, pp. 3703-3706, November 15, 2000
http://www.tampa.phys.ucl.ac.uk/djedjiga/GL11096W01.pdf

Abstract. New laboratory measurements and theoretical
calculations of integrated line intensities for water vapour
bands in the near-infrared and visible (8500-15800 cm−1) are
summarised. Band intensities derived from the new measured
data show a systematic 6 to 26% increase compared
to calculations using the HITRAN-96 database. The recent
corrections to the HITRAN database [Giver et al., J. Quant.
Spectrosc. Radiat. Transfer, 66, 101-105, 2000] do not remove
these discrepancies and the differences change to 6 to
38 %. The new data is expected to substantially increase the
calculated absorption of solar energy due to water vapour in
climate models based on the HITRAN database.


Conclusions
Table 1 (Final column) also sets out values for the comparison
of our “best” total intensities of the water polyads
with those given in HITRAN-COR. It should be stressed
that the line intensities of our observations and the HITRAN
database differ from line to line and that the given values
are only valid for room temperature. The measurements
at 252K yielded slightly different ratios, but are omitted
here for clarity. For a major fraction of the lines, the principal
part of the change takes the form of a re-scaling of
the data on a polyad-by-polyad basis, we recommend the
use of the factors set out in Table 1 as an interim solution.
Other databases, such as GEISA [Jacquinet-Husson et
al., 1999], are based on the same laboratory data and will
therefore require the same correction. Detailed line-by-line
data including both experiment and theory will be published
[Schermaul et al., 2000].
There is another lesson to be learned. Making sure the
database is valid is necessary foundation for all modelling
of atmospheric radiation transfer, especially so when theory
and observation fail to agree.


In short, if I read this correctly, then the climate models have been already proven
to be vastly underestimating the role of water vapour in the planet's climate that they supposedly model.
AND, therefore greatly overestimating the role of radiation within the planets climate system.
It is not a case of arguing the strength of the supposed positive water vapour feddback mechanism, but,
it is the magnitude of the figure, which is negative not positive, that is the real issue.
It is THE ISSUE which is being dismissed, or ignored, and consequently sending "climate science" and mainstream "climate science skepticism" down the WRONG blind alley..
When, and what will it take for so many to wake up from the seemingly all pervading "radiation obsession" of modern "climate science"?

That will upset a lot more "doubtful neighbours", I would suspect.


Attached Files
.pdf   Absorption by Water Vapour - Some problems with the HITRAN Database - Belmiloud et al. 2000.pdf (Size: 235.18 KB / Downloads: 461)
The whole aim of practical politics is to keep the populace alarmed
(and hence clamorous to be led to safety)
by menacing it with an endless series of hobgoblins, all of them imaginary.

H. L. Mencken.  

The hobgoblins have to be imaginary so that
"they" can offer their solutions, not THE solutions.
Reply
#8
Nice one! I missed it. (link at end needs looking at, link in text worked fine)

Heartening to read verification of my personal layman observations. Gallavanting round various parts of the world provided me with information far more valid than any computer model programmed by someone who has never been past the end of his home street.

HITRAN - Hah! :thumbdown:
Environmentalism is based on lies and the lies reflect an agenda that regards humanity as the enemy of the Earth. - Alan Caruba
Reply
#9
I have tried to post another comment on the same thread,
http://tallbloke.wordpress.com/2011/08/2...mment-8455

" Does the diurnal bulge effect "things", in terms of
direct incoming sunlight path length through atmosphere,
and,
"Note the increase in atmospheric path length for reflected light, longer inwards and then longer outwards."

Then there is absorption by water vapour en-route, does this convert to sensible heat? Presumably convected away.

Any comment re "insulation" issue with experiment I raised earlier?
"

I note some interesting, although I suspect slightly "off target", discussion of Richard111's metal plate issue...

AND, also a couple more very interesting pdfs posted,
so I have attached them to this post.

ALSO, Elsewhere someone, very kindly, has been looking at this threads mug experiment from an "enthalpy" point of view.
I think however it is an unnecessary "diversion".
There is far more to be got from the experiment "as is", such as
changing mug shape used, to increase / decrease surface area / volume ratio,
and,
specific heat capacity of the material of the container used (one very close to water heat capacity / emissivity would be good, as well as distinctly higher and lower).

I wonder if "we" can get to radiative losses, sensible heat losses and latent heat losses, quantified individually?
I think it might be possible.
Latent heat losses are presumably the difference between the "oily" and water only mugs (remembering oil is lower heat capacity than water, so "oily" mug is cooler from sensible heat losses only).
"Oily" mug is sensible plus radiative looses, so if radiative heat losses can be worked out mathematically,
hey presto,
take radiative losses from "oily" mug radiative and sensible heat looses, and,
"we" have all three to compare.


Also, "we" might be able to compare the effect of wind upon the rates of losses for the 3 different means heat / energy is lost from the mugs.

I think "this" will have to be included in this pdf as I develop it.
The solar and geothermal powered refrigerator called Earth - forum review.


Attached Files
.pdf   Polarized_IR_WaterEmissivity(OptEx25342) Shaw Marston.pdf (Size: 188.34 KB / Downloads: 410)
.pdf   Unresolved issues in Atomspheric Solar Absorption William Collins.pdf (Size: 1.06 MB / Downloads: 446)
The whole aim of practical politics is to keep the populace alarmed
(and hence clamorous to be led to safety)
by menacing it with an endless series of hobgoblins, all of them imaginary.

H. L. Mencken.  

The hobgoblins have to be imaginary so that
"they" can offer their solutions, not THE solutions.
Reply
#10
Hi All,
An open question from me, I would really appreciate some help with.

What about the work done overcoming the surface tension of water, when,
liquid water is vapourised into it's gaseous form.?


I mean the often quoted figures for latent heat, do they include the energy required to overcome water's surface tension,
which if water is to turn from liquid to gas, presumably must be overcome.
Hence vapourisation is so strongly endothermic - it requires a lot of energy.

If this "Prof Tyson" The latent heat fallacy "territory" Richard111 previously mentioned elsewhere on the forum (that I basically dismissed without much consideration - Blush ) then, so be it.

If the present quoted latent heat figures do include, but do not separate out, the work done of vapourisation then,
does this mean that condensation is not as exothermic as presently thought?
Would this explain why modelling has such a problem with condensation?
They are simply modeling too much energy being released by condensation.
ie, Should the vapourisation of water (liquid to gas) be far more endothermic (require far more energy)
than condensation (gas to liquid) is exothermic (release far less energy)?

How would the work done of overcoming the surface tension of liquid water effect the energy budgets,
if that energy is not apparently conserved???
Reply
#11
Good luck with that Derek. I'm still battling.
My current reasoning: put a measured amount of water into a pot, note the starting temperature and the time, put the pot on the stove and record time taken to reach 100C (boiling point). From this you can calculate the the energy in joules per second that went into raising the measured quantity of water to 100C.

Leave the pot boiling until say half the measured quantity of water is gone. Record the time. You will now have the number of joules per second that went into the vaporisation of a known quantity of water.

Be much easier and more accurate to use a bunsen burner and a test tube and a stop watch but either way energy is definitely going into the vaporisation of the water. Where is that energy? What can happen to it?

Must go and read Tyson again and see how he counters the above argument (if he does).
Environmentalism is based on lies and the lies reflect an agenda that regards humanity as the enemy of the Earth. - Alan Caruba
Reply
#12
Richard111, I think you will like this...

Firstly,
" If the present quoted latent heat figures do include, but do not separate out, the work done of vapourisation "
Yes the present quoted figures do include this work done of overcoming surface tension during the vapourisation of water.

Secondly and more importantly,
I have been in email conversation with someone, who I will hopefully say who it is later,
and he has been explaining an answer to the surface tension question I have asked.

In short (if I have understood properly),
Yes, vapourisation does take more energy than condensation releases.
ie, vapourisation is more endothermic than condensation is exothermic.
The difference is due to gravity, or rather altitude, and therefore potential energy, between where the vapourisation and condensation occurs.
Rain falling back to earth conserves the apparent energy difference between vapourisation and condensation.

So, IF "the consensus" views / explains / models the vapourisation and condensation of water at different altitudes, as equally endothermic and exothermic,
therefore ignoring the potential energy of that mass (water is relatively very heavy),
they are wrong, and at a large scale.

The whole aim of practical politics is to keep the populace alarmed
(and hence clamorous to be led to safety)
by menacing it with an endless series of hobgoblins, all of them imaginary.

H. L. Mencken.  

The hobgoblins have to be imaginary so that
"they" can offer their solutions, not THE solutions.
Reply
#13
Hi All,
I am developing another version/s, of the above "oily" mug experiment.
So far, I am getting consistent, and quite startling results.
They are making an interesting excel sheet and plots....

I'll hopefully be posting a "can be done by anyone at home" version / description soon.
The "delay" in posting is because I am asking "behind the scenes" that what I observe,
is what I think it is that I am observing.....
The whole aim of practical politics is to keep the populace alarmed
(and hence clamorous to be led to safety)
by menacing it with an endless series of hobgoblins, all of them imaginary.

H. L. Mencken.  

The hobgoblins have to be imaginary so that
"they" can offer their solutions, not THE solutions.
Reply
#14
Due to other time constraints I have not been able to follow this experiment up as I would like to yet.

In the meantime I hope the attached excel sheet shows where I have got to so far.
It would seem open water can never be in thermal equilibrium with the atmosphere,
this appears to be because of the latent heat losses from the water surface driven by relative huidity within earth's gravity field.
The "oily" tray version of the experient which is what is in the attached excel sheet, and below photographs.
I think it is an experiment anyone can perform to confirm or show my results so far to be in error, or to be correct.

Link to album
http://s53.photobucket.com/albums/g43/De...xperiment/

[Image: oilysetup.jpg]

[Image: Calmsetup.jpg]

[Image: trays.jpg]

[Image: Windysetup.jpg]


Attached Files
.xlsx   Derek GWS - Oily mug experiments calm 1 and windy 1 excel sheet.xlsx (Size: 88.04 KB / Downloads: 268)
The whole aim of practical politics is to keep the populace alarmed
(and hence clamorous to be led to safety)
by menacing it with an endless series of hobgoblins, all of them imaginary.

H. L. Mencken.  

The hobgoblins have to be imaginary so that
"they" can offer their solutions, not THE solutions.
Reply
#15
Follow up proposed 3rd experiment - please see attached.

Apologies, this copy has missed off the bottom line.
The bottom of the image should read,
IF results confirm hypothesis and predictions then.
Proves,
- Latent heat the most powerful cooling mechanism.
- Convection is only a positive catalyst.

Comments / thoughts invited.

I am awaiting delivery of
http://www.ebay.co.uk/itm/180834270508?s...1423.l2649
then I should be able to do the experiment.

NB - Dashed line in jpeg illustration is where bottle is cut off for "control" versions of wet and dry versions of experiment.
So, that is 4 experiment runs in total.


Attached Files
.jpg   Derek Latent heat experiment March 2012 small.jpg (Size: 228.74 KB / Downloads: 260)
The whole aim of practical politics is to keep the populace alarmed
(and hence clamorous to be led to safety)
by menacing it with an endless series of hobgoblins, all of them imaginary.

H. L. Mencken.  

The hobgoblins have to be imaginary so that
"they" can offer their solutions, not THE solutions.
Reply
#16
Derek, might be some information for you here:

Seawater Evaporation Experiments: Determining Relative Evaporation Rates

From comment at tallbloke's.

Off to read it myself now. Rolleyes
Environmentalism is based on lies and the lies reflect an agenda that regards humanity as the enemy of the Earth. - Alan Caruba
Reply
#17
Not very helpfull really. I'm not sure I understand the area used for the grams per day figures. It'll come in the fullness of time I guess. Undecided
Environmentalism is based on lies and the lies reflect an agenda that regards humanity as the enemy of the Earth. - Alan Caruba
Reply
#18
Thank you Richard111, I will follow that link when time allows.

I hope what I do here will be so simple as to not need much explanation.
It is all about heat pipes really, and they are not too difficult to understand.

[Image: Slide13.jpg]

and,
[Image: Slide14.jpg]

and,
[Image: Slide15.jpg]

not forgetting,
[Image: Slide10.jpg]
The whole aim of practical politics is to keep the populace alarmed
(and hence clamorous to be led to safety)
by menacing it with an endless series of hobgoblins, all of them imaginary.

H. L. Mencken.  

The hobgoblins have to be imaginary so that
"they" can offer their solutions, not THE solutions.
Reply
#19
Hi All,
I am still constructing and testing the suggestion in post 15.
I am up to mk3 now...

mk1 works well.
mk2 works no better than mk1 ???
This puzzled me, I wonder if the difference between dry and wet adiabatic lapse rates is like a "lag" or "governor" in the real world system.
Maybe that is why most heat pipes are insulated along their length...
Anyway, I am now working on a mk3.
All dead cheap, so anyone who wants to repeat it for themselves should be able to for not a lot of money.
I hope this ends up making the power of latent heat a lot less esoteric.

HELP REQUEST.
In the mean time does anyone know how to get 4 or preferrably 10 of these working on one computer at the same time recording separate data sets?
http://www.ebay.co.uk/itm/ws/eBayISAPI.d...Track=true
PC USB Powered Thermometer Temperature Sensor Data Log Auto Email
Functions:
Brand new high quality!
Measures the PC temperature in real time, and measures other things via external sensor
External sensor can measures liquid
Measurement data is stored in PC and easily copied into Word or Excel
Read data directly on temperature curve diagram
Data can be sent to presetted email address
Data is displayed in °F or °C
Data is automatically recorded in log file
Measurement accuracy is up to 0.0001
High speed USB interface, compatible with USB 2.0/1.1/1.0
Parameters:
Measurement range: -50°C ~ +150°C for external sensor
Dimensions: 50 X 17 X 8 mm
External sensor cable length: 1 m
Package:
1 X USB thermometer
1 X CD driver


This would be a massive help as I can only seem to get one working at a time at present.
The whole aim of practical politics is to keep the populace alarmed
(and hence clamorous to be led to safety)
by menacing it with an endless series of hobgoblins, all of them imaginary.

H. L. Mencken.  

The hobgoblins have to be imaginary so that
"they" can offer their solutions, not THE solutions.
Reply
#20
Interesting little gadgets Derek, nice price too. Looks like you will need TWO laptops for simultaneous readings. Smile My laptop has three USB ports. Could the recording program be directed to a specific port? Else get the gadgets from WUWT, rather expensive though!
You might find this pdf interesting but does not help your experiment.

http://www.waderllc.com/Finley/Evap_Paper.pdf

To me it seems evaporation of surface water is NOT dependant on temperature, although that helps. Vapour pressure (humidity level), and wind speed seem to be more effective. Also I have a problem with water surface area. Okay for a mill pond but even the smallest waves INCREASE surface area.

How do you work out the length of a line with a 2 inch amplitude sine wave along a distance of 1 metre? Square that and you get the surface area. Big Grin

Very strong winds cause BREAKING waves and FOAM. What then?

Environmentalism is based on lies and the lies reflect an agenda that regards humanity as the enemy of the Earth. - Alan Caruba
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