re: #9 LudwigVanQuixote

A Runaway Greenhouse Effect?

The atmosphere would finally stabilize at a still higher temperature and pressure after all the carbon dioxide had been driven from the rocks. In fact, we believe that if this sequence were to take place on the Earth, the resulting temperature and pressure of the atmosphere left behind would not be very different from that for present-day Venus: the atmospheric temperature would be hundreds of degrees Celsius and the pressure would be maybe 100 times greater than it is today.

Thus, we believe that in the case of Venus the initial solar heating kept oceans from forming, or kept them from staying around if they did form, and the subsequent lack of rainfall and failure of plant life to evolve kept the carbon dioxide in the atmosphere rather than binding it in the rocks as is the case for the Earth; thus, Venus has an environmental disaster for an atmosphere.

The sobering warning for us is obvious: we have to be extremely concerned about processes such as burning of fossil fuels in large volumes that might (we don’t know for sure because the scientific questions are complex) have the potential to trigger a runaway greenhouse effect and produce on the Earth atmospheric conditions such as those found on Venus.

Exactly as I suspected - contrary to troll denier claims, it’s not the “atmospheric pressure” on Venus that caused it to warm, but the exact opposite - the runaway greenhouse effect caused the heating which in turn made the atmosphere that dense and that thick.