If Global CO2 Emissions Were Black Smoke Coming From a Giant Broken Pipe in Texas

Watching the video of the BP oil gusher bleeding into the Gulf of Mexico, I got thinking about how this imagery (and all the heart-wrenching photos of oiled wildlife) makes the problem so real and easy to comprehend.  We get it, and it makes us sick.

One of the widely-discussed problems with the public's acceptance of the science underlying global weirding is that the heat-trapping gases that are disrupting the climate are invisible.  Plus, these heat-trapping pollutants come from so many different places -- cars, trucks, buses, inefficient homes and buildings, industrial processes, deforestation, landfills, you name it -- that their flow into the atmosphere and their impact on the earth's climate and people is hard to "see".

Which leads me to a question: if all the Earth's heat-trapping pollution was colored black and came from a giant broken pipe in the middle of, say, Dallas, (1) how big in diameter would the pipe have to be, and (2) how long would it take for the plume of black smoke to spread from Dallas to other major metropolitan areas around the world?

If somebody with graphic design skills could put together this kind of computerized imagery, it would be powerful stuff...
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