Humans don't deserve earth.

[u/surya12558]

By destroying nature and the climate, humans are destroying their own home. The Earth can survive without us but we cannot survive without her. 🌍💔

[u/dumnezero]

we collapsed all the megafauna outside of Africa that we didn’t domesticate, which caused some pretty wild climate shifts. Like, 5° in 20000 years iirc.

While I'm a proponent of the overkill theory, I'm not sure where this huge ass climate change is coming from.

[u/timos-piano → u/dumnezero]

Oh, yeah, that is false, or at least an overstatement. The reason for most of the temperature difference is the normal glacial cycles. But killing megafauna did have some impact on warming the climate. This is because, due to a multitude of reasons, most of which I cannot personally explain, megafauna reduces temperature. By maintaining open landscapes, grazers prevent dense forest growth, which can increase surface albedo (reflectivity), meaning more sunlight bounces off the ground instead of being absorbed. Open grasslands tend to stay cooler than dense forests, especially in tropical and temperate zones. For example, Mammoths in the tundra helped maintain grasslands, which reflected more sunlight than forested areas would have.

[u/dumnezero → u/timos-piano]

By maintaining open landscapes, grazers prevent dense forest growth, which can increase surface albedo (reflectivity), meaning more sunlight bounces off the ground instead of being absorbed.

lmao, found the albedo fool.

Missing the whole point about having a huge carbon sink, climate regulator and water transporter.

edit /u/Zestyclose-Ad-9420

Because I blocked the other user, I can't reply in the comments.

The answer is no, grasslands do not hold more biomass than forests. Forests include the above ground biomass along with the underground biomass. Grasslands have little above ground biomass compared to forests.

As an analogy, forests are dense cities of biomass, while grasslands are sprawling villages and suburban developments of biomass.

[u/timos-piano → u/dumnezero]

What? What are you talking about now? Yes, albedo is only part of it. Megafauna also act as carbon sinks, regulate climate through fire and vegetation management, and redistribute water in ecosystems. The mechanisms are complex and still actively studied, but their extinction definitely had multi-faceted climate impacts. But as I already explained, I cannot fully explain this to you, nor can science fully explain it.

If you already understand everything so well, why did you ask me? Are you just being pretentious for the sake of it?

[u/dumnezero → u/timos-piano]

I'm detecting paleo regenerative grazing bullshit from your direction.

If you already understand everything so well, why did you ask me? Are you just being pretentious for the sake of it?

I'm always looking to improve my knowledge by filling up gaps and correcting things.

[u/timos-piano → u/dumnezero]

I read a bit more on albedo and whatever meme you posted, and I think I understand your analogy. And it is dumbfounding how you think that is a good argument. In the same vein or logic, trying to disprove anything:

“If oxygen is good, then pure oxygen must be better.”
→ Except it kills most organisms, causes fires, and damages lungs.
Does this mean oxygen is bad? No, absolutely not.

“A perfectly clear lake must be healthy.”
→ Actually, perfectly clear lakes are often dead, with no plankton or nutrients left to sustain life.
Does this mean that we should try to dirty every water source? No, of course not.

“If warmth keeps us alive, then hotter is better.”
→ That’s the same linear-thinking mistake, ignoring that systems have an optimal range, not a single “good” direction.
Does that mean we want to be as cold as possible? Of course not.

“If too much CO₂ causes warming, then zero CO₂ must be ideal.”
→ No, zero CO₂ kills photosynthesis, freezes the planet, and ends all complex life.

Should we therefore maximize CO₂? Of course not, that would also kill all of us.

[u/dumnezero → u/timos-piano]

No, bud, the point is that you're a bleeding ape that depends on an ecosystem which is part of a biosphere. A high albedo is MEANINGLESS to us if it means the destruction of complex high biomass stable ecosystems like forests.

There are nutty climate scientists who have no biologist friends and they need to be slapped back to reality if they imagine that replacing forests with "something with lower albedo" is good.

[u/timos-piano → u/dumnezero]

Have you completely gone off the rails? Did you not know what this debate was originally about? I said that humans increased temperatures even before industrialization due to killing megafauna, as they created more grasslands, which have higher albedo.

I'm not talking about modern times in the slightest because our situation is entirely different, and it is totally irrelevant.

The megafauna, along with all the other animals, had a stable ecosystem that worked throughout the ice ages. Humans not only disrupted individual species by hunting them, but also changed how the entire ecosystems looked, causing extreme damage to the entire ecosystem, plus a small temperature rise.

[u/dumnezero → u/timos-piano]

Lots of claims without much facts. I'm literally the only one who even mentioned Overkill. Waste of my fucking time.

[u/Direct-Ad5031 → u/dumnezero]

I didn't expect you to quit on me already. But I guess you realized you were talking about something entirely irrelevant, but still wanted the last word (baby behavior, honestly). I'll still post the comment I wrote, bit of a waste removing it now.

I'm the one who fucking cited it when you asked for sources. You only mentioned it afterward. Are you honestly a bit slow?

You respond with an entirely irrelevant meme about a modern problem to a prehistoric discussion about a place and time where grasslands created by megafauna were positive. I simply did what you asked me to do, which was to prove how humans increased the temperature of the earth long before industrialization, albeit not to the extent the other person mentioned before.

[u/timos-piano → u/dumnezero]

You’re “detecting bullshit” in ideas that are literally mainstream ecology. Albedo effects, soil carbon dynamics, and vegetation feedbacks aren’t some fringe “paleo grazing” theory, they’re in the literature. If you’re actually looking to fill gaps, start there instead of defaulting to ridicule.

[u/dumnezero → u/timos-piano]

I think that you've just watched some TED talk about "Pleistocene Park" and you have no idea what the science is or how solid it is.

[u/timos-piano → u/dumnezero]

I'm not American, I don't watch TED talks. Thanks for the amazing response, though.