[zosima]

This is a very interesting read:

https://www.cambridge.org/core/journals/journal-of-glaciolog...

They have found some meltwater layers with unexpectedly large quantities of CO2 > 750ppm.

But they also show that there is unexpected heavy diffusion around the meltwater layers. And they argue very compellingly, that the ice core CO2 records have been smoothed through natural diffusion.

Why is this information not given when showing this graph?

[MichaelZuo]

>750 ppm CO2 is incredible, if that's true it's no wonder that interglacial maximums could have been 5 degrees warmer than present day.

What's the causal explanation behind that much CO2 though? Super-volcano eruptions?

[zosima]

They explain in the paper. It's very likely an artifact.

But from the layers around it, it becomes clear that through the years these high CO2 bubbles leak CO2 to nearby layers.

And so CO2 highs are diminished in the ice core record and CO2 lows have been raised.

[MichaelZuo]

But in the case it's not an artifact?