Snowball Earth theory says entire earth was covered in an ice sheet dozens of miles high. There might have been a ring around the equator of unfrozen water or slush.
It seems very hard for life to survive under those conditions, let alone complex life, let alone advanced life / civilizations.
What evidence do you have that there is some such thing as a "balanced world ecology" at all? It seems to me that all the evidence, in addition to logic, is in the opposite direction.
I guess I share your problem, I’m not sure “balanced” is the right word. You could have two species, a single celled animal and a single celled plant and ostensibly that would be “balance”.
Maybe a better word for what is at risk is “diversity”. At this time there are still wild ecologies with incredible diversity in all three phases of water on Earth, the frozen, the liquid, and the steamy.
And there are also partly dead places. The American Midwest is largely ecologically dead, although we know before the European settlers came there was stable soil and incredible biodiversity there.
But balance and biodiversity are connected. In a diverse ecology, you can remove any species, or turn any dial slightly, metabolism will dip, and then roar back into full power because there is so much latent genetic material in the ecology ready to go.
That’s been destroyed in a place like the Midwest. If you stop putting oil into that ecology, the metabolism would plummet, and it would take a million years to return to anything close to what it was before European settlers.
In a so-called “balanced” ecology, metabolism would rebound on a scale of decades or even seasons.
The moral assumption underlying this is that the most metabolism per square foot of solar energy is the most good.
Ok, I think we are talking about two different things:
One thing is biodiversity and the ecological resilience of biodiverse systems, of which there are many (still) where different species live in a healthy, productive and dynamic balance. These habitats are under attack for sure, spurred by industrial production modes of various kinds.
Quite another thing is the notion (represented by GP if I'm correct) that the whole earth somehow is a balanced system, were it not for greedy humans. This is a mystical belief that I don't see any proof of.
It is far-fetched not to think that comet impacts, massive volcano eruptions and/or solar radiation variance accidentally could make most if not all ecological systems devoid of life, quite without human intervention.
tl;dr, It was a light-hearted ironic idea, not some statement on the impending downfall of human civilization
"that the whole earth somehow is a balanced system, were it not for greedy humans"
This was in no way implied by what I said!
I think the word balance is justified here, the word I got wrong was ecology (I meant climate, but it was late, and I didn’t expect such a defensive response to my joke,…).
Either way, both the climate and ecology of earth work by balancing conflicting interests and drivers. food chains, carbon cycles, etc.. all are based on interlocking processes that combine to create a system that is stable at a macro level (Of course localized factors can make things seem much less stable). But on the whole, these systems are balanced. Things periodically come along and upset that balance, and it takes a while for the system to adjust and re-balance, typically with a result that is different from before.
My point was that it would be ironic if ANY civilisation got to the level where it could alter these systems meaningfully, but by doing so, and not understanding what/how they were doing things, created a situation where not only were they wiped-out, but also all trace of their technology was wiped-out too.
I accept that this exact scenario is extremely unlikely, as our current models predict that in these situations, at least some of the population would survive due to those localized factors, but the civilisation could easily be destroyed by sudden and climactic shifts.
It's unclear (to the best of my knowledge) if we would expect the historical record of such a thing to be carried by these people, but a lot of the detail of our knowledge of roman and pre-roman times(1,000s years, not millions) has been derived from archeological records, so it's not unreasonable to assume that if Ice were to scour all hard evidence of such things from the surface of the earth, then the knowledge of such may die out or become so garbled that it ceases to be believed.
Of course there /are/ parallels with the situation modern humans find ourselves in. I think there's little doubt that what we do has an effect on the balance of the world's climate and ecological systems (you eat a chicken, that has affected the food chain by an infinitesimal amount), but how much impact we will have, and our ability to comfortable adapt to any resulting changes would require a much longer response, and isn’t relevant to my original post at all :)
What I meant was that this hypothetical civilisation supposedly flourished in a particular environment. If their actions altered that environment radically enough to wipe them out, AND wipe out all traces of their existence, then that would be an interesting idea to consider
> the survivors would have lived relatively comfortably in smaller populations in habitats
A million years gives a pretty long time for unlikely events to occur that could finish the job of wiping them out. Wars and engineering accidents and diseases and such.
Like you I tend to be of the opinion our human civilization will survive any kind of global cataclysm that Earth could throw at it... But I am less convinced a population forced under a million individuals could survive - million years just under the normal chaos of existing.
I suspect there is a minimum population and geographic diversity required for our long term survival. Not sure where those red lines are though.
> it is hard to imagine a culture having sufficient technological capability to cause climate change without also achieving space flight
What does that get you? You can’t orbit Earth for a million years without refueling. And the rest of the bodies is pretty inhospitable. What’s the best case there, a million people on Mars with a few decades of preparation? What’s the probability of such an outpost surviving?
Look at our own history as a species. We seem to have expanded outward from equatorial regions that were lush, warm, and filled with wildlife. Nearly every need we had could be met with minimal effort. And we rapidly moved outward into areas that were cold, desolate, dark, and where even not freezing to death would have been a challenge.
In more modern history people set off into seas with no idea where or if they would ever end, in ships no way well designed for oceanic travel. And there was a very real belief that these seas were infested with giant monsters that would destroy ships. Many would have seen such voyages as little more than suicidal endeavors at one time.
Getting even more modern consider space. We went from the New York Times publishing pieces suggesting that space flight would be impossible (arguing that rockets would lack anything to 'push' against in space) to having a permanently manned station orbiting the Earth some 16 times a day, along with all of its crew.
The point of this is that everything seems impossible at a distance, yet rarely is that the case. We feel like we're near the top of a mountain looking at the final insurmountable face. Only to eventually discover that not only is that face entirely surmountable, but it was nowhere near the top. Once we've colonized Mars, and perhaps other inner system bodies, people will again eventually consider such achievements of little relevance with interplanetary travel becoming as mundane as intercontinental flight is today. And they too will ponder off thinking about how unimaginable colonizing planets in star systems outside our own would be... and the cycle continues. The only reason colonizing Mars, indefinitely, seems out there is because that's where we currently are on the mountain.
Climate change is certainly surmountable. What makes me sad is what’s lost along the way. Humanity survived the colonization of the America’s. But it also lost some irrecoverable things.
I can definitely understand this point of view, but there's also another way of looking at things.
Nobody in a million years would have ever wished for something like the Black Death. It was a catastrophe like none before (at least that we know of) and certainly none since. It claimed the lives of upwards of half of the human population in Europe. Such a catastrophe, yet it played a major role in setting into the motion the social changes that would eventually lead to the end of feudalism and the advent of mercantilism. It played a key role in shaping a vastly more liberated society.
Or consider nuclear weapons. These weapons were only used against other people twice. It was a heinous act with immense cost. Yet far beyond just ending that war - as was the purpose of their use, those weapons of unimaginable destruction signaled the end of all outright warfare between developed nations. It makes one wonder if in some parallel world, if the weapons' destructive power was never demonstrated on humans might we have been more likely to eventually end up in nuclear annihilation with countries, such as in the Cold War, far more willing to press that red button?
Should human caused catastrophic climate change should come to pass it's not particularly hard to foresee the lessons and behaviors we might learn and enact from such. And one can only imagine what social changes might occur. Of course would indeed be much nicer if this was not how we collectively learned, but a civilization and a young child have one thing very much in common. You can tell them not to put their finger in the fire all you want, yet they will inevitably learn that lesson not by instruction but by scorched digit.
