5 Year Member
- Mar 16, 2014
- Location (City and/or State)
- NW suburbs of Chicago
Yes, those pictures were not mine. I got them from here. He also talks about dehydrating lamps as well .: POST #66
...This water vapor is what is being absorbed by by the suns IR-A spectrum. This spectrum is water hungry. Absorbing all the water it can find. If there is not enough water present. The emission is "unfiltered". If there is a enough water present (our atmosphere) then it is "filtered".
Here is the thread explaining it way better then I can by someone who knows so much more than me.
OK, didn't realize the grid image wasn't yours...
Perhaps a little help in understanding what was being said by the post you referenced by lilacdragon would be of value. Please refer to the first chart, Solar Radiation Spectrum, as a visual aid. We can ignore the 5250 C Blackbody Spectrum as it is irrelevant to the clarification.
Water and water vapor absorb IR-A not the other way around (electromagnetic waves cannot absorb anything). The absorption of IR by water causes it to heat. Heat causes evaporation of water which if not contained will cause the dehydration of an object containing water.
Note the yellow graph (solar radiation above the atmosphere) and that it maintains a smooth but declining power curve throughout the spectrum including IR-B & [if the graph was expanded] IR-C. The sun emits unfiltered wavelengths - just like a coffee percolator 'emits' unfiltered coffee.
Note the red graph (solar radiation at sea level), particularly the dips labelled H2O. These are the wavelengths that are being absorbed by water and water vapor. That absorption (i.e. removal of part of the spectrum) is what is referred to as filtered - just like sunglasses remove parts of the spectrum and provide filtered light. Much of the spectrum is filtered (absorbed, reflected or refracted) by dust, gases and other obstacles in the path of that radiation as can be seen in the unlabeled dips in the sea level graph (like UV-C is mostly filtered by the atmosphere [thankfully!]). Just like a coffee filter removes the grounds from percolated coffee yielding filtered coffee.
I hope this helps to clarify what is really happening. I am not trying to say that coconut oil (or any other hydrophobic material) covering the carapace won't potentially reduce the water loss via evaporation. Actually, I would expect that some spreading of the heating will occur if only simply by conduction of heat through the oil. Which is why we use oil to fry stuff!
Thank you for that clarification. I really appreciate that. I interpreted the idea of "filtration" oppositely then. So are you saying there is possibility to spread out the heating as a result of these lamps because of conduction through the oil? So essentially would the oil would be "locking" in moisture or just distributing heat thus preventing water evaporation and some localized heating as a result of these lamps?
The oil could be doing both. That's where the control group and variations on the theme provide additional data from which conclusions can be gleaned.
I always thought the thermal diffusivity of oil is very low (that's why mammals use adipose tissue for insolation). So I assume that the EVCO would rather slow down the process of heating up. But physics has never been my strong point, maybe you can explain this to me?Actually, I would expect that some spreading of the heating will occur if only simply by conduction of heat through the oil. Which is why we use oil to fry stuff!
I have read that in the wild tortoises get plant oil on their bodies by passing through vegetation, and many species, also in dry climates, are "manipulating" moisture exposure by choosing where to go, under leaves, bushes or in burrows. The idea of applying plant oil in an indoor enclosure is therefore very good.
Whether it helps distribute heat evenly I cannot say, but the idea is sound. The pictures also show some very well to do tortoises. My compliments!
By the way: Does your house have a balcony on a second floor? It could give you an enclosure. I have the same problem with animals and criminals.
Regards from 60 degrees north
Why overheated? An insulation does both - it keeps warm things warm and cold things cold. I believe the shell would warm up better/faster without the oil.
I looked it up, thermal diffusivity of oil seems to be about 0.1 and bone is about 0.3 (depends on density,....). But maybe I'm wrong in my reasoning.
If my reasoning is correct (as I said, Physics was never my strong point), it makes a difference, the heat would spread slower than without the oil. But that's purely hypothetical.So if it is a thermal diffuser even as small as .1 , couldn't that still make even the slightest difference in the way it spreads heat over the carapace
Do you own the property? If so can't you build a fence? you can also build a very sturdy enclosure and bring your tortoise in at night. most of the really harmful critters are out at night anyway. just wondering, natural sunlight is the best thing for a tortoise if at all possible.I don't unfortunately.. just a massive backyard thst is open with free range , German Shepard sized coyotes, massive skunks, possums and raccoons. I parallel a big forest preserve. I appreciate the offer, quite so.
Do you own the property? If so can't you build a fence? you can also build a very sturdy enclosure and bring your tortoise in at night. most of the really harmful critters are out at night anyway. just wondering, natural sunlight is the best thing for a tortoise if at all possible.
It is my understanding that because most other oils and coconut oil traps heat. So, if you apply after the tort warms up it should hold and help evenly keep the distributed evenly more so than applying when the tort is cool. Also, it is my understanding that because coconut oil is preferred over aloe for sunburn relief it is strongly advised not to use it for prevention as the oil absorbs most uv rays and thus trapping more heat. Just wondering what the results would be if you applied after warming up. Not sure if you have tried that already or not.