There are styles in science. Tamino, for example likes to look at statistical models. James Annan thinks about priors, Gavin Schmidt cranks up his GCM, Stoat goes rowing (we exaggerate for effect). Eli, OTOH, likes to think about and then do simple experiments or calculations (BOE aka Fermi problems: some interesting examples)
Recently, this blog, and others went to the mattresses about the idea that the greenhouse effect acts like a blanket. As you may recall Atmoz had previously used an actual blanket and concluded that blankets cut off convection and conduction, but don't have much effect on radiation. Eli pointed out that survival blankets do cut off radiation, but several people thought that they also cut off convection. For those of you who don't know, a survival blanket is a thin piece of plasticized metal foil that you wrap around yourself when the heat goes out on the space station, or your return capsule lands in Siberia. If you go to Eli's link you will see an example.
So Eli started thinking and came up with the following. Take a lightbulb and wrap it tightly with a thin layer of aluminum foil. This cuts off radiation from the light bulb (the lamp light is reflected from the shiny foil), but since the foil is a good heat conductor, conduction and convection from the surface of the foil should be pretty much unchanged with or without the foil.
This is an experiment that you should ONLY do if you have a clue about handling electical stuff. There IS a significant shock hazard if you let the foil touch the metal base of the lamp, but Eli IS an electric bunny, and stuffers are insulators, so he took a 75 W incandescent lamp and put it into a drop light (there is some danger of the lamp shattering if the temperature gets too high) and turned it on. Eli found that the top of the lamp was hottest, and he measured the temperature with a thermocouple (it's handy to have a lab): 160 +/- 5 C. Next he turned the lamp off, let it cool and wrapped it with a single layer of thin (cheap) aluminum foil and turned the lamp on again: 300 +/- 5 C.
Eli rests his case, besides which he just heard some guy on the Weather Channel talking about how clouds and water vapor act like thermal blankets when the sun goes down, and how it cools off a lot faster when the sky is clear and it is dry.
DO NOT DO THIS UNLESS "YOU" KNOW HOW TO WORK WITH LIVE ELECTRICAL EQUIPMENT. Eli Rabett, Rabett Labs and everyone else assumes no responsibility for anyone who tries to duplicate this. There is a significant chance you could be nominated for a Darwin Award if you are careless.
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