A part of my John Everett series – read more: 0/I – II.0 – II.5 – II.75 –  III.0 – III.3 – IV.0 – IV.4 – IV.8 – V – VII – VIII – Full Report 

Last time we looked at Dr. Everett’s testimony, we examined his claim that, because carbon dioxide levels have been higher in the past, increasing levels are not alarming now. His argument is flawed, because although CO2 levels have changed, they usually change only very slowly. Now, they’re changing abruptly. Graphs of Deep Time can be intuitively misleading, because they collapse time scales and it can be hard to compare the rates of change from one image to the next. For example, this next graph shows information that we have gathered from looking at  gasses trapped in Antarctic ice. It’s obvious that the climate changes over Deep Time- but is it obvious from this graph how historical rates of change compare to modern rates?

Paleoclimatic and paleogeochemical data gathered from the Vostok ice core. Temperature (red) and carbon dioxide (blue) go up and down on these time scales - but its the rate that really matters. Click for sauce.

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