RCP8.5, baby! Line must go up!
this post was submitted on 18 Nov 2024
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We're not quite that bad right now; efforts already taken probably dropped it to something more like 3°C of warming by 2100 with further warming thereafter.
not quite that bad
Except several experts have surmised that at 3ºC we will experience civilizational collapse. Stefan Rahmstorf, for example, said recently that “We simply wouldn’t reach three degrees because... we’d be in such deep trouble that basically the economy collapses.”
That's still the lowest end of RCP8.5. Many are projecting that we could be on RCP4.5 once we reach where the pathways would diverge (2050), the problem with that is it assumes some large scale CCS and a flatlining of emissions (net zero). If those happen, then 3 degrees might be a top end and we'll only have a small amount of catastrophe(?!).
My disbelief is a number of things - human nature to change is a big one, I can't see us changing much without a huge motivational reason (read major disasters and/or population decrease from impacts). Another is the physics of CCS, the scale needed for any large effect is just beyond anything we can do, and I think it might be far more than just the energy requirements, so say a fusion breakthrough may not improve the abilities. Lastly, the feedbacks that will be set off as we go into 2 degrees will take over the path the Earth's environment changes towards, and we can't stop them.
We need to continue to talk about heavy reductions in emissions, which also means lessening consumption and growth of everything. Not only to reduce the future results, but to prepare for living in a harsher world where that kind of society can't exist. We're in an extinction event, and we better pre-adapt before it's necessary otherwise we'll be one of the species. That may already be a foregone conclusion, but it will be a certainty if we continue how we've been going.
By 2030 we are going to be 40% over capacity on fresh water resources globally.
This massive drought is likely to kill a few billion people around the world before the massive global famine will get the rest of us.
40% of arable land has already been depleted and 95% will be by 2050.
And this is just water and food.
Once arctic ice sheet coverage gets below 1,000,000 square kilometres, the planet will be absorbing more heat than it reflects. This is called a Blue Ocean Event and this will trigger the Clathrate Gun Hypothesis
2024 Arctic sea ice likely reached its annual minimum extent of 4.28 million square kilometers.
Greenhouse gas emissions are still increasing and Fuelled by climate change, the world's oceans have broken temperature records every single day over the past year.
So it's basically a race between if the drought and famine will kill us all first, or the BOE setting off the Clathrate Gun will. Either way, it is unlikely the human race survives the century.
(Edited to trim that weird BOE link that didn't format fully and to combine that dought/famine sentence so it parsed better.)
Which efforts, exactly? The Keeling curve shows zero impact, and the other greenhouse gases are worse.
Thats... Disastrous...
Yeah, I think given current trajectories somewhere between RCP 3.4 and 4.5, with emissions peaking around 2050. Given technological and political headwinds, I just can't see emissions peaking in 2080 or 2100 with growth rates already slowing globally and peaking in North America and Europe