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by ahevia 1612 days ago
While you correctly pointed out that human activity is contributing to climate change. You forgot to mention how unprecedented the rate at which the climate is changing. A process that normally takes tens of thousands of years is happening within a 3-4 human lifetimes. Far too quickly for organisms to adapt.

“Doom & gloom” is a defined differently to many people. What exactly do you mean here? Are humans going extinct & Earth is going to become uninhabitable? I certainly don’t think so.

1 comments

Again, to reiterate: I'm not denying human impact on climate change. Let's just get that out of the way.

But your claim about rate of change, which is often repeated, is actually wrong [1]:

> Unlike the relatively stable climate Earth has experienced over the last 10,000 years, Earth's climate system underwent a series of abrupt oscillations and reorganizations during the last ice age between 18,000 and 80,000 years ago ... There are twenty-five of these distinct warming-cooling oscillations (Dansgaard 1984) which are now commonly referred to as Dansgaard-Oeschger cycles, or D-O cycles. One of the most surprising findings was that the shifts from cold stadials to the warm interstadial intervals occurred in a matter of decades, with air temperatures over Greenland rapidly warming 8 to 15°C (Huber et al. 2006). Furthermore, the cooling occurred much more gradually, giving these events a saw-tooth shape in climate records from most of the Northern Hemisphere (Figure 1).

[1]: https://www.nature.com/scitable/knowledge/library/abrupt-cli...

Regardless of whether or not high rates of change happened in the past, they're not good for stability of life. That 10,000 years of stability was crucial to the evolution of our species and most food we eat (wheat being a huge example). So I don't think you can shrug it off and say "pah, this all happened before". So did WWII, and I wouldn't like to repeat it just because.

We're looking at mass extinctions, loss of whole ecosystems, more wildfires, more storms. Not good things. Worse if you do it to yourself.

We're looking at mass extinctions either way. The holocene extinction started before anthropogenic climate change began and will continue even after we restabilize the climate. There's a lot more we'll have to do if we want to protect our remaining wildlife.
> Regardless of whether or not high rates of change happened in the past, they're not good for stability of life.

Let the moving goalposts begin.

If the last 10,000 years of relative climate stability is unusual--and it seems to be at least within the context of the last 100,000 years--then how can you argue it's "bad for life"?

This is the point of my comment: people have a warped view of "normal" as being the first thing they experience.

For example: sea level changes in the last 20,000 years are massive [1]. Over that time the Sahara was a desert, became tropical and became a desert again (~6200 years ago) [2]. Climate change is viewed by many as a significant factor in the Bronze Age Collapse [3].

> So I don't think you can shrug it off and say "pah, this all happened before". So did WWII

Seriously?

[1]: https://judithcurry.com/2011/07/12/historic-variations-in-se...

[2]: https://en.wikipedia.org/wiki/Sahara#:~:text=By%20around%204....

[3]: https://www.latimes.com/science/la-xpm-2013-aug-15-la-sci-sn...

> If the last 10,000 years of relative climate stability is unusual--and it seems to be at least within the context of the last 100,000 years--then how can you argue it's "bad for life"?

Edit: I'm not arguing that 10k years of climate stability is bad for life. The opposite, actually.

I don't really think that the climate of 100,000 years ago matters too much, aside from the fact that our species (and those we rely on) survived. The critical difference is the last 10,000 years of relative stability is the period during which human population reached billions. I'm sure we can survive a return to inclement weather, but we probably won't thrive.

I’m aware of D-O cycles. I also wasn’t calling you a climate denier don’t worry.

The rapid rate of change induced by human caused warming still isn’t going be followed by a global cooling like D-O cycles. D-O cycles also occurred in a world that was still wild and not overdeveloped. The Earth’s biosphere was far more resilient back then. I don’t really see the point youre making? Was it just to disprove a statement I made?