Show HN: BornAtXCO2 – What CO2 PPM were you born at, how much has it increased

Post by hntroll1110 » Mon, May 17, 2021, 12:47 AM UTC

cung wrote: post #8

hntroll1110 wrote: post #3

Earlier quoted context omitted.

I don't find it horrifying. Not that long ago, CO2 ppm was twice what it is today. Before that, it was twice that . If we could travel through time, we could drop you in that world and you'd be fine, other than the fact that the world would be an incredibly dense jungle. History shows that we're not particularly close to any dangerously high amount of CO2; we were much closer to a dangerous low amount, since plant re…

Just so that this isn’t unclear to anyone, a quick search for historical CO2 shows how absurdly wrong this comment is.

Post by hntroll1110 » Mon, May 17, 2021, 8:09 AM UTC

cung wrote: post #12

URfejk wrote: post #9

Earlier quoted context omitted.

Carbon dioxide concentrations dropped from 4,000 parts per million during the Cambrian period about 500 million years ago to as low as 180 parts per million during the Quaternary glaciation of the last two million years: https://en.m.wikipedia.org/wiki/Carbon_dioxide_in_Earth%27s_...

I would argue 500 million years ago is not ”not so long ago”. The Cambrian period also didn’t have more than a microbial soil crust living outside of oceans.