### The famous scientist cuts through the global warming noise and lays out the facts (4:33)

Courtesy of: Climate Reality Project

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Numbers are the Supreme Court of science. However Godel proved that we may not prove everything. Science needs numbers. There must be Science and Physics Foibles!!

From a scientific viewpoint, this is a bad video. The demonstration lab experiment is misleading and technically unsound. Bill, you are a mechanical engineer. You should have the sense to look at the experiment, and realize that the greenhouse effect from the carbon dioxide or air in the glass jars is negligible in determining the equilibrium temperature of the thermometer. In the laboratory, a glass jar at close to room temperature will have insignificant radiative heat transfer when the temperature difference is only a few degrees. (Try plugging some numbers into the black body radiation formula, where T is within about 10 degrees of 300K.) Under such a temperature difference, the heat transfer by conduction and free convection within the glass jar is NOT insignificant. As it turns out, the thermal conductivity of carbon dioxide is less than that of air. A reference for this can be found, for example, at http://www.engineersedge.com/heat_transfer/thermal-conductivity-gases.htm. This difference in thermal conductivity is great enough to explain the difference in equilibrium temperatures that you observe. (Under the ideal gas law, the volumetric heat capacity should be about the same, between the two gases, so it is reasonable to estimate that heat transfer by convection also is the same.) Thus, the difference in the internal jar temperatures do NOT demonstrate the greenhouse effect, but rather a difference in thermal conductivities of two different gases. It is just a lucky coincidence that CO2 is a better thermal insulator than air. How long has this video been public? Am I the first person to point out this flaw in your experiment? Regards, Jon Spear www.spearlab.com http://ssg.als.lbl.gov/ssgdirectory/spear/spear.htm p.s. I am NOT a climate change denier. I just want scientific information to be presented correctly.

All that's missing is a throwback music video parody. Love this, thank you Bill!

Hello Smithsonian! Long time reader first time writer. Good job with the video but surveys show it would be 238% more effective (share worthy; viral) if Bill NYE made a cameo.

This video is short & even if used for G.W.Change (global warming change)propaganda does not have a convincing enough argument, even for the I.P.C.C. to use effectively,well-meaning though it may be.For a start,is carbon dioxide really such a culprit? There have been higher levels previously which did much to stimulate plant growth.Have we looked clearly at the possibility that G.W. MAY prove to be part of the Malankovitch cycle and nothing to do with anthropogenic causes.Fast developing nations like China & India,will continue in their use of fossil fuels.Limiting our use will serve only to put greater industrial power in their hands - to our detriment.What of alternative,new sources of power,such as fracking & other,as yet undiscovered possibilities.Too much money is being made in Brussels by the sale of Carbon Credits etcetera.with good wishes,P.G.

No closed captions? Or am I just not seeing them?

Great video!