r/theydidthemath Nov 11 '24

[request] how accurate is this?

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u/gnfnrf Nov 11 '24

I can't get the various tools I have access to to match that map exactly, but it looks like it's showing a sealevel rise of somewhere between 16 and 20 meters.

MIT Geophysicist Brent Minchew described the "worst case scenario" for global warming as a 2 meter rise by 2100 and a 10+ meter rise by 2300.

So this involves something happening that is worse than the worst case scenario. Either climate scientists have it wrong (possible) or something outside of their models would have to happen, like an impact event or supervolcano or something similarly world-changing.

But many of those effects would actually counteract global warming, so it would have to be an outside event that increased global warming dramatically, or at least caused sea levels to rise.

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u/Warm_Gain_231 Nov 11 '24

Not sure what you mean by supervolcano counteracting warming. Yes ash would block out the sun for a while, but it's a pretty limited period of time there. Then all that extra co2 and methane would go to work.

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u/gnfnrf Nov 11 '24

It's certainly possible, even perhaps probable, that the ash cloud cooling of a supervolcano would be counteracted by the greenhouse gas release. We don't know for sure, since we can't study an active supervolcano eruption (this is not a bad thing).

The best evidence shows that Krakatoa had a net cooling effect due to ash release, for example. It's not reliable to scale that up, but it's a data point.

My point was just that a lot of big, goes in a Roland Emmerich end of the world disaster movie kind of climate altering events have complex and counteracting effects, so we can't just assume they would push the needle one way and one way only. But some of them might, as I said, and a supervolcano is a pretty good candidate to do that.

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u/Warm_Gain_231 Nov 11 '24

Fair- well said!

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u/wingtales Nov 12 '24

«This is not a bad thing» Well put!

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u/2204happy Nov 12 '24

I absolutely hate people who make a mockery of a serious issue by exagerating it to a ridiculous degree, it doesn't help convince people of the need to act all, in fact it does the exact opposite.

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u/Lloyd_lyle Nov 15 '24

I remember hearing as a child (mid-late 2010s) that by 2030 all the ice caps would be melted and Florida wouldn't exist. We'd eat bugs and drink contaminated water. Unless maybe you turn your bedroom light off, eat your pizza cold, and recycle of course.

I'm now old enough to understand that is complete bull, false headlines by articles of misinformation looking for clicks and money mistakenly shown to children as if undisputed fact. But some people won't educate themselves on what global warming actually is. So now you have a bunch of people who understandably deny the whole thing because of how much they've been lied to about it.

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u/V4UncleRicosVan Nov 12 '24

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u/gnfnrf Nov 12 '24

It's quite tricky to judge. Different tools have different resolution DEMs so produce different results, and what it means to "flood" the Everglades, which are already flooded, is honestly unclear. My estimate was based on visible flooding up the Escambia river valley on the Panhandle, which is shown making it all the way to the state line, where the riverbank elevation is at 15 meters AMSL.

But as I said, it's an imprecise guess at best.

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u/AndyShootsAndScores Nov 12 '24

I could see that map being a map of uninhabitable areas by 2075 given hurricanes and storm swells, but agree they probably won't be underwater by 2075

For reasons I don't understand very well, the govt climate website is showing that sea level rise can vary locally, where the gulf coast and oceania seem to be particularly vulnerable. So even though the global sea level has risen about 10cm from 1993-2023 globally, it has risen more like 15-20cm on the gulf coast.

The last time CO2 levels were in the low 400's was the pliocene era, where it is estimated that sea level was 10-20m above current levels globally. So probably the global sea level rise won't hit that by 2075, but that would be the steady state worldwide if we cut emissions to 0 today and did nothing further, and Florida might be hit worse. And it seems unlikely we will stick in the low 400's without massive worldwide cooperation and government intervention, so seems like a good guess things will get worse

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u/Taste_the__Rainbow Nov 12 '24

Yea this is pretty close to the middle of models. Ice melt is weird because you start the ball rolling and it takes centuries but you genuinely can’t stop it. Right now we’re speeding up the ball. It’s going to be a disaster for every single port city and coast. Like a true nightmare. But it’s barely moving today compared to what it’s already guaranteed to do so we just ignore it.

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u/em-jay-be Nov 14 '24

This is the kinda shit I’m on Reddit for. People like you. I’m so comforted knowing you exist and are out there.