[ghastmaster]

I find it hard to reconcile that the entire world is going to be going through cycles of drought and flooding over and over due to a moderate increase in temperature and co2. Where in earth's history is the basis for this? We have had far higher temperature and co2 levels during periods of great animal and plant growth.

[polotics]

Well with more CO2 you have more convection, the higher atmosphere is actually cooling because of the nice CO2 blanket that keeps heat trapped lower. (Which by the way prooves that it's not the sun's natural variability that's the cause, otherwise the higher atmosphere would also get warmer) This temperature differential between low and high atmosphere then means more convection, more evaporation, more movement of air and water. Look just read up on this ok, it's not that hard.

[namaria]

Previous temperature changes occurred over millennia, not a century and a half.

Human civilization and agriculture depend on a very narrow range of conditions.

[ghastmaster]

So the levels aren't the problem, it's the rapidity?

> Human civilization and agriculture depend on a very narrow range of conditions.

I'm in Ohio, USA. Are you from the Arctic by any chance? Maybe Australia? How about Mongolia? Perhaps Brazil? Mozambique? We live and thrive in all of those unique areas. Very narrow conditions indeed...

[ben_w]

> So the levels aren't the problem, it's the rapidity?

Only in the sense that it's not the fall that kills you, it's the rapid deceleration at the end.

Evolutionary time (for us and our crops) is much longer than the "approximately one human lifetime" in which it will have become necessary to have adapted substantially. Genetic modification for humans and crops might work if you don't care about the entire rest of the ecosystem.

Ice core measurements go back 800,000 years, which is longer than humans have been human (about 300k). In all that time, up to the industrial revolution, CO2 only varied been about 170 and 300 ppm, its now about 420 ppm and rising so fast it's a vertical line on any graph that shows all the ice core data and is less than 8000 pixels wide.

> I'm in Ohio, USA. Are you from the Arctic by any chance? Maybe Australia? How about Mongolia? Perhaps Brazil? Mozambique? We live and thrive in all of those unique areas. Very narrow conditions indeed...

Figure 5, primary production spacial map and graph of temperature and precipitation vs output.

https://essd.copernicus.org/articles/12/2725/2020/

"Where you can physically reside" != "the foundational input into your civilisation".

You may think your food comes from the supermarket, but that's just a convenient abstraction because the foundation has not been broken.

[pjc50]

> So the levels aren't the problem, it's the rapidity?

Pretty much. If it was happening over a 100k year timescale nobody would care except the geologists.

[namaria]

> So the levels aren't the problem, it's the rapidity?

Not what I said. You argued it has been hotter before and it wasn't a problem. I had to explain to you that temperatures haven't changed this fast before, which is a strong argument for the antrhopogenic nature of the current change. It also illustrates the danger of the current phase, since the thriving ecosystems of millions of years ago didn't have to deal with such sudden change.

> I'm in Ohio, USA. Are you from the Arctic by any chance? Maybe Australia? How about Mongolia? Perhaps Brazil? Mozambique? We live and thrive in all of those unique areas. Very narrow conditions indeed...

Don't conflate narrow global conditions with narrow set of landscapes. The holocene has been remarkably stable in terms of climate and civilization thrived due to this stability.

You're clearly arguing in bad faith and I feel no need to engage further