If this is true, we're fucked.

at a temperature increase of 4 degrees C:

• Sea rise of ~9m, putting 470-760 million at risk
• Frequent and severe extreme droughts
• Mass extinctions, risk of ecosystem collapse
• Food insecurity, regional de-development
• Half of all animal species face local extinction

Huh I guess that Arctic news blog guy was right.

Caveat: preprint, not yet peer reviewed.

There’s no way they can know that. There won’t be anyone alive to measure after 8 degrees. Checkmate science 🧬 /s

Here's a summary of the paper from ClaudeAI. So it's not perfect but for anyone who doesn't want to read the entire paper and wants a decent summary:

Here is a summary of the key points from the scientific paper:

• The paper examines climate sensitivity, defined as the equilibrium global temperature change caused by a doubling of CO2. Based on analysis of paleoclimate data from glacial and interglacial periods, the authors estimate the fast feedback climate sensitivity (ECS) is likely around 4.8°C for doubled CO2, higher than the IPCC estimate of ~3°C.

• Climate response time, the time required to reach a new equilibrium after a forcing, does not seem to be getting faster in climate models even with improvements in ocean mixing. This is likely due to amplifying cloud feedbacks buffering ocean heat uptake and slowing surface warming.

• Analysis of deep ocean temperature proxies over the Cenozoic era (past 66 million years) suggests CO2 levels were around 300-350 ppm in the Pliocene and 450 ppm at the transition to a nearly ice-free planet. This has implications for climate model sensitivity.

• Aerosols likely have a more negative forcing than estimated by IPCC, based on the warming gap between models and observations. Restrictions on shipping emissions provide an opportunity to study aerosol effects.

• The climate forcing from current greenhouse gas levels likely commits to 10°C warming including slow feedbacks like ice sheets, or 8°C if aerosol forcing remains around -1.5 W/m2. This shows the planet is far out of energy balance.

• The authors argue that reducing emissions alone is no longer adequate - additional actions to reduce the energy imbalance like solar radiation management may be needed to avoid locking in multi-meter sea level rise.

In summary, the paper suggests climate sensitivity and committed warming are higher than widely assumed, implying an urgent need for policies beyond just reducing emissions.

Hey, at least we won't be around to find out what happens if you add PFAS, aluminum, microplastics and other nanoparticles into an existing species over multiple generations.

And still that’s just a conservative outlook. It’s going to be way way worse.

Yea, no grandchildren for you mommy and daddy.

So 10° is going to be an ELE? We aren't going to be here by 2100 are we? Atleast not in the current way we live anyway.

That's 18 degrees F for people who still use that

PDF warning next time please.

We're basically on course for infinite warming. By the time anyone decides "maybe we should, like, seriously, try to fix this?", we'll be turning into Venus.

I hope this paper gets peer reviewed - I want to believe it so bad as I agree with the general ideas (people ignoring feedback loops and other factors which impact the climate as well). Though I do wonder sometimes if there are any remaining negative feedback loops which we aren't aware of, and might help as CO2 levels worsen. It certainly seems like we're already aware of all negative loops (the ocean, plant life, rocks?, etc), so we're really only missing the positive loops