Comment by trophycase
8 years ago
It's not true that a stable equilibrium is always reached. It's also possible that irreversible changes are set into motion which shift the equilibrium so far away from livability that humans cannot survive.
8 years ago
It's not true that a stable equilibrium is always reached. It's also possible that irreversible changes are set into motion which shift the equilibrium so far away from livability that humans cannot survive.
See, for instance, https://en.m.wikipedia.org/wiki/Clathrate_gun_hypothesis
What kind of time scales does this suggest?
> A study based on a coupled climate–carbon cycle model (GCM) assessed a 1000-fold (from <1 to 1000 ppmv) methane increase - within a single pulse, from methane hydrates (based on carbon amount estimates for the PETM, with ~2000 GtC), and concluded it would increase atmospheric temperatures by >6 °C within 80 years
Am I reading this right that it would take 80yrs to get to +6c, so it would still be a gradual increase? Is it an exponential increase?
Anyone recommend a documentary about this?
For what it's worth, +1.5c is deemed bad and +2c is deemed abominably abhorrent; if the midpoint is +3c in 40y, that's bad, but if the majority of the temp growth is in the latter half (ie it's monotone but convex), that would be a damn crunch imo
This has been happening throughout history of Earth. Just look at all the ice ages (including the most recent so called little ice age).
Just cca 11,000 years ago, without any human intervention (nobody driving SUVs around back then), temperature has risen dramatically which caused massive ice sheets on top of North America and Europe to melt. This caused sea levels to rise by 120 meters, swallowing an area of land larger than China and Europe combined.
Until this day we still don't know what caused that (and it seems to be a reoccurring event as it has happened multiple times). The last time it happened it has caused extinction of most of megafauna (with some remnants surviving in Africa as it was least affected).
We are struggling to cope with sea levels rising by 1-2mm per year. Imagine if they rose by 120m in couple of years. All coastal mega cities - NYC, SF, Tokyo etc would be underwater completely.