It's the difference between stocks versus flows: the flow has been negative for the last 40 years, depleting stocks accumulated over the last n hundred million

It's the difference between stocks versus flows: the flow has been negative for the last 40 years, depleting stocks accumulated over the last n hundred million years. Earth overshoot day is defined from the imbalance in flows, it doesn't capture what's going on with the stocks. Things will get exciting when the stocks are reduced below critical thresholds, that'll generate a bunch of obvious symptoms, but the underlying problem is the imbalance in flows. This is all a bit abstract, for something more concrete in terms of specific quantifiable metrics, one arbitrary place to start is the 2009 paper "Planetary Boundaries: Exploring the Safe Operating Space for Humanity Space for Humanity". https://pdxscholar.library.pdx.edu/cgi/viewcontent.cgi?article=1063&context=iss_pub https://pdxscholar.library.pdx.edu/cgi/viewcontent.cgi?artic... Figure 6 estimates that the rate of biodiversity loss, climate change, the nitrogen cycle all exceed estimated boundaries defining a safe operating space for humanity.