this post was submitted on 16 Jan 2024
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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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[–] Telorand@reddthat.com 59 points 10 months ago (3 children)

It's unfortunate that "Global Warming" was the phrase that got lodged in the public's collective brain, because it's such a terrible summary of what is actually happening, and idiots run with it.

[–] remotelove@lemmy.ca 29 points 10 months ago* (last edited 10 months ago) (1 children)

It can be super difficult to understand, especially when it's easy to present the same data in multiple ways. Global warming is a thing, and climate change is a thing, but it's hard to fully experience because daily weather is so variable.

For example, if you look at the last 2000 years of data, we are starting an extremely rapid temperature increase. If you zoom out to a the last 500 million years, our global temperature is still changing, but it doesn't appear to be extreme.

People just don't realize that homosapiens only really appeared 200,000 years ago and our distant ancestors started showing up 7 million years ago. Point being, we started evolving in a climate that was cool and then got colder.

For perspective, the first fungi are thought to have first appeared 650 million years ago. They have seen it all and eventually said "fuck this" and now mostly live underground. For good reason.

It's the acceleration of global warming that is bad. In the last few thousand years, we have erased ~25 million years of the last cool down period. That is bad. Very bad.

The earth will survive climate change just fine, maybe. We won't, though.

Disclaimer: All numbers are basic estimates and data changes faster than I can keep up with. I am not a scientist, but I can read charts. For my summary here, I used these:

[–] Telorand@reddthat.com 8 points 10 months ago

All fascinating stuff, even if concerning.

I like this video from Gutsick Gibbon that talks a lot about evolution as it relates/related to climate change and what our future may hold if we don't change.

https://youtu.be/uxTO2w0fbB4?si=bYoBldeh02glM9wR

[–] Auzy@beehaw.org 3 points 10 months ago

Problem is, idiots always cling to whatever is most beneficial for them anyway.

EV's are the perfect example.. They ignore the cost saving or time saving (if you charge from home), and at the moment are focused entirely on battery fires (which are more rare than ICE fires), towing capacity (for whatever reason, they seem to think they need to tow 4 tonnes), and seem to have forgotten that both ICE and EV's need prewarming in cold climates.

[–] FabledAepitaph@lemmy.world 2 points 10 months ago

The book Hyperobjects by Timothy Morton is a good read

[–] LibertyLizard@slrpnk.net 30 points 10 months ago* (last edited 10 months ago) (1 children)

This is an interesting and somewhat counterintuitive phenomenon but we’ve seen it multiple times in recent years. The central and northern US seem particularly vulnerable to these arctic outbreaks, but so far it’s typically coincided with warm, dry weather in California—this year seems to fit the mold as well. But is this just coincidence or is it always going work that way?

This has big impacts on my work as an arborist—we’re trying to shift our palette of trees towards more southerly species to prepare for future heat. But if we occasionally experience exceptional cold, this can hamper those efforts as it can be deadly to more southern species. So far California has not seen this particular pattern but it only takes once for serious damage to occur.

[–] jadero@slrpnk.net 10 points 10 months ago (1 children)

I know this doesn't help with your project, but here's how I've managed the "intuition" part. Note that this is just the mental model I have, not actual science.

The jet stream (also known as the polar vortex when it dumps cold air southward) is powered by the temperature difference between the arctic and the subarctic. The arctic is warming faster than the subarctic, so the temperature difference is being reduced. That reduces the power of the jet stream.

The jet stream is like a wall that separates the arctic from the subarctic. As it gets weaker, arctic air "breaches the wall" or maybe the "wall" just relaxes and moves south.

Even though the arctic is rapidly warming, it's still damned cold, so it causes all kinds of problems when it escapes.

It could be just pattern seeking, but I feel that we in southern Saskatchewan are getting yo-yo weather as a result of greater fluctuations in the jet stream. We're just coming to the end (I hope!) of a dangerous cold snap. The week before it was near freezing (shirt sleeve weather around here at this time of year) and the forecast for next week is more of the same.

Good luck with the trees!

[–] tryptaminev@feddit.de 6 points 10 months ago* (last edited 10 months ago) (1 children)

https://www.dw.com/en/when-the-jet-stream-weakens/video-62097932

here is an explanation video with animations at around the 2:30 and 5:00 min mark.

The fast wind was moving more or less straight. Now that it slows down, it gets a wavy pattern, that also moves slower. As a result we get more stable cold zones and more stable heat zones. As these move slower over the planet, it results in longer cold and heat waves, with adverse weather. So the boundary doesn't get "breached" in one direction, but rather it relaxes in both directions, getting the yo-yo weather you describe.

[–] jadero@slrpnk.net 3 points 10 months ago

Thanks, that makes it a lot clearer for me.

[–] toaster@slrpnk.net 5 points 10 months ago* (last edited 10 months ago)

I liked this analogy:

It’s like an ice skater spinning rapidly with her arms tucked in, he said. But when the polar vortex weakens, the arms start flailing out, the skater slips and “all the cold air then gets released away from the center of the polar vortex,” Cohen said.

The current cold outbreak is consistent with Arctic change and the polar vortex, Cohen said. “What we found is when the polar vortex stretches like a rubber band, severe extreme winter weather is much more likely in the United States. That’s where it tends to be focused and in January we have an extreme case of that stretching of the polar vortex.”

[–] Art3sian@lemmy.world 3 points 10 months ago* (last edited 10 months ago) (2 children)

If the world warms enough and the Greenland glaciers melt into the ocean, a mini Ice Age can occur in as little as 50 years.

People don’t understand that we will freeze before we bake, and of the two, freezing will end our civilisation more assuredly.

[–] LibertyLizard@slrpnk.net 22 points 10 months ago* (last edited 10 months ago) (2 children)

I don’t think this is really in line with current predictions. If you are referring to the weakening or collapse of the North Atlantic ocean currents, this will lead to substantially colder temperatures only for Northern Europe, though it will have other large effects on other regions as well. But it will not be comparable to an ice age from a global perspective—the rest of the world will remain extremely hot.

[–] Art3sian@lemmy.world 4 points 10 months ago* (last edited 10 months ago)

Yes, I’m referring to ocean currents and how I’ve understood it, is that they carry warm currents from the equator to the poles which is a main driver of warm weather cycling the planet.

Once the ocean currents stall we lose that warmth transference and everything subsequently freezes, and quickly. Not globally, but around the 30th latitude, north and south which is enough to make Europe, Asia, North America and half of Argentina near uninhabitable.

Correct me if I’m wrong but isn’t high C02 levels and global warming the reasoning behind the last Ice Age, circa. 11,000bc?

[–] nexusband@lemmy.world 2 points 10 months ago* (last edited 10 months ago) (1 children)

You do realize, the classification of having or being in an ice age is basically North- and Southpole are covered in ice/snow? We have not left the ice age.

An ice age is a long period of reduction in the temperature of Earth's surface and atmosphere, resulting in the presence or expansion of continental and polar ice sheets and alpine glaciers.

[–] LibertyLizard@slrpnk.net 2 points 10 months ago

Sorry I was speaking colloquially. I should have said glacial period.

[–] XTornado@lemmy.ml 1 points 10 months ago (1 children)

And how long would last this Ice Age. Because you call it "mini" but not sure if you mean it duration, in temperatures or what....

[–] Art3sian@lemmy.world 2 points 10 months ago* (last edited 10 months ago)

I’m not sure to be honest. I think both? I think ‘mini’ is the planet partially frozen except for the equatorial region, and the duration is a few thousand years opposed to perhaps tens or hundreds of thousands.

But I’m guessing based off the last one. It’s a good question. Either way, it’s a bad time for bald apes who’ve forgotten how to hunt.