this post was submitted on 08 Dec 2023
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Climate - truthful information about climate, related activism and politics.

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Discussion of climate, how it is changing, activism around that, the politics, and the energy systems change we need in order to stabilize things.

As a starting point, the burning of fossil fuels, and to a lesser extent deforestation and release of methane are responsible for the warming in recent decades: Graph of temperature as observed with significant warming, and simulated without added greenhouse gases and other anthropogentic changes, which shows no significant warming

How much each change to the atmosphere has warmed the world: IPCC AR6 Figure 2 - Thee bar charts: first chart: how much each gas has warmed the world.  About 1C of total warming.  Second chart:  about 1.5C of total warming from well-mixed greenhouse gases, offset by 0.4C of cooling from aerosols and negligible influence from changes to solar output, volcanoes, and internal variability.  Third chart: about 1.25C of warming from CO2, 0.5C from methane, and a bunch more in small quantities from other gases.  About 0.5C of cooling with large error bars from SO2.

Recommended actions to cut greenhouse gas emissions in the near future:

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[–] Burn_The_Right@lemmy.world 22 points 11 months ago (1 children)

Either the victims kill those most responsible, or those most responsible kill the victims. There is no other outcome.

Fossil fuel executives and their conservative syncophants cannot change. It is not possible. They can only be changed by force.

[–] Asafum@feddit.nl 6 points 11 months ago

Username absolutely checks out lol

[–] guriinii@lemmy.world 14 points 11 months ago (1 children)
[–] Rhaedas@kbin.social 2 points 11 months ago

I.e, how long ago? Probably about the time the 1.5 target number was being introduced, and that may be optimistic.

[–] benjhm@sopuli.xyz 3 points 11 months ago (2 children)

It’s kinda trivial to show that impacts at 2ºC are much worse than at 1.5ºC. What nobody has done is shown that the difference between 1.6ºC and 1.5ºC is so much more than between 1.5ºC and 1.4ºC, and therefore that this is the key threshold at which we must stop /panic /revolt /give-up-and-party /whatever ... What matters is the curvature of the function, to see curvature you need at least three points within the range of choice (acc to Paris 1.5-2.0). So more info about impacts at 1.75ºC could help. I told them this during scenario planning discussions over a decade ago, but the big earth-system-model guys just mumbled about "signal-to-noise-ratio" - they preferred to run RCP8.5 (the extreme high scenario that - fortunately- is looking so implausible it may be dropped from next IPCC round), because the higher the scenario, the more exciting graphics they make, the more funding they get..., but this didn't help to show why we need more effort from all, at the bottom of the range.

[–] silence7@slrpnk.net 3 points 11 months ago (1 children)

Most of the exact boundaries for ecological tipping points aren't known with an 0.1ºC precision. I don't think we're going to get something like what you are asking for, just knowledge that each incremental increase in temperature is another step into a minefield.

[–] benjhm@sopuli.xyz 1 points 11 months ago (1 children)

True, but in principle we (i.e. big teams) could make impacts functions for each case and combine by integrating over risk (within which, value judgements also make a big difference - but that's something to learn too). To fit those functions we needed more studies by ESMs with smaller differences at the low end - if you don't study it, you won't know it (hence my point years ago - those models are slow, and big committee-run processes even worse).

[–] silence7@slrpnk.net 1 points 11 months ago (1 children)

Sure, it would be nice to know, but I don't see knowing as likely to change policy in any kind of meaningful way. That's going to take changing who holds power, not incremental knowledge.

[–] benjhm@sopuli.xyz 3 points 11 months ago* (last edited 11 months ago) (1 children)

I agree about that too - and think about how to model these power dynamics. Maybe you're suggesting (by this + posting the original) that we influence politics more by emphasising the crisis, regardless of the shape of that curve of increasing impacts. Such logic could also justify why they like to run high scenarios in ESMs. This doesn't convince people like me, but I know my way of thinking is not so typical, so maybe you are right.
Otoh there are some influential people, especially those who trust black boxes of economic optimisation models (there's another recent thread about that), for whom the lack of such info could effectively provide an excuse for delayed action.

[–] silence7@slrpnk.net 1 points 11 months ago

My impression is a lot of the high-emissions scenarios being used lets you demonstrate that there is an impact easily, even if the actual date of that impact looks to be somewhat later than under the most likely emissions scenarios.

And yes, the economic models are particularly awful; DICE has a bunch of assumptions in it about economic impact not affecting sectors which operate indoors and about damage being in the form of a fraction of GDP for that sector. eg: if agriculture is 3% of the economy by value, and it goes to zero, the overall impact is a 3% cut to economic output, even though no food means no economy.

The human brain is not reasoning with power functions.

While I agree with you I think the root for people not understanding properly, or dont want to is not about how the data is presented its simply in cultural heritage and in general no self motivated thinking.

People shut down when the information is to bipolar to their beliefs and and even if they keep listening they cant comprehend one step further because its too abstract.

[–] riodoro1@lemmy.world 2 points 11 months ago

Same article about passing 2C in three years.

[–] Asafum@feddit.nl 2 points 11 months ago (1 children)

I wouldn't be able to help myself and I'd answer: .5C would be the key difference, well that and a lot more death. Lol?

[–] silence7@slrpnk.net 4 points 11 months ago

Death and loss of a bunch of key life-supporting ecosystems

[–] jadero@slrpnk.net 2 points 11 months ago (2 children)

I'll take a stab at answering the headline.

1.5C is anything from mild inconvenience to pretty bad news, depending on where you live, how old you are, what you do for a living, and your financial resources.

2.0C is anything from pretty bad news to very bad news depending mostly on where you live and how old you are.

[–] FarraigePlaisteach@kbin.social 8 points 11 months ago (1 children)

We’re already past mild inconveniences. Poeople loosing their homes, land and livelihood for years now.

[–] jadero@slrpnk.net 4 points 11 months ago

I know that, which is why I specified a range that included pretty bad news and qualified the range based on several factors, especially where you live and your current age.

Climate disaster is not just a statistical artifact, but has real people in specific situations. That means, regardless of temperature, there will be significant differences in personal experiences depending on how old you are right now and where you live right now. At 1.5C what you do for a living right now and your current financial situation play significant roles; not so much at 2C and beyond.

[–] silence7@slrpnk.net 3 points 11 months ago

Pretty much. The article goes into detail.