Gregory's Server@petergleick What happened before that 800k years and why (other than that's as far back as ice samples go) did you decide that was the place to start?
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@petergleick Which is really not answering the question. For instance, the last time there was a period of CO2 as LOW as we have it now, the latter half of the carboniferous period, it resulted in global glaciation. Historically, since that time, the ppm has been around 2000. So the question is, why is the greenest point in our carbon history unattractive, and the coldest and unhospitable time desirable? @elliswyatt @petergleick CO2 in the above is from the gas bubbles trapped in ice cores — there is older ice than 800000 years, but it has been chewed up and altered and complicated, thus not done yet (https://cp.copernicus.org/articles/18/1563/2022/cp-18-1563-2022.html). Before that, you can use pH from the ocean to infer CO2 in the atmosphere. http://www.p-co2.org/boron# |
@elliswyatt There are actually good data showing that current CO2 levels are higher than anytime in the past 5 MILLION years. The graph goes back 800,000 to cover the excellent quality ice-cores data.