"Sorry. Preacher man gotta preach. What’s not so obvious is the incredible difference in leverage between these two substances. To put enough of this stuff"—he slapped the carbon bell jar, and his wedding ring made a sharp noise on the glass—"into the atmosphere to bring the temp up a couple degrees, we had to put a large part of the human race to work burning shit for two centuries. We chopped down forests, dug up peat bogs, excavated huge coal mines, emptied oil reserves the size of mountains. Hell, in Afghanistan they even burn shit . All that disappeared into the air. The total weight of excess carbon we put into the atmosphere is about three hundred gigatons. All those trees, all that coal, all the oil and peat and shit. Now. To reverse that change in temperature—to bring it back down by two degrees—how much sulfur do you think we need to put into the stratosphere? A comparable amount? Not even close. A smaller amount? Yes, but that don’t do it justice. Because sulfur has leverage like you wouldn’t believe. This amount of carbon here"—he once again did the wedding ring thwack on the bell jar full of black stuff—"could be neutralized, in terms of its effect on global temperature, by an amount of sulfur too small to be seen by the naked eye. So small that we couldn’t even demo it in these bell jars unless I rolled out a microscope. Tomorrow you’ll see the ratio. A boxcar of coal, and a cube of sulfur you can put in the palm of your hand."