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(Thread) Too often, people tell me, "OK, I believe in thermometers, and it's getting warmer. But how do we know it's caused by humans & not natural?"
As an archaeologist who studies humans in deep time, my answer is, "B/c then we'd be heading towards another friggin ice age"
1/9
As an archaeologist who studies humans in deep time, my answer is, "B/c then we'd be heading towards another friggin ice age"
1/9
I'm serious, If it wasn't for humans, we'd be in the Holocene, a short period of warming (10,000 years-ish) between longer ice ages (90,000 years-ish)
The planet should be going (very slowly) into another ice age
The spikes below represent short warm periods b/t ice ages
2/9
The planet should be going (very slowly) into another ice age
The spikes below represent short warm periods b/t ice ages
2/9
Climatologists in the 70s realized that, naturally, the Holocene represented a short warm period
Alarmed, they sent President Nixon a letter warning abt the need to prepare for the eventual onset of a new ice age
This made sense given the minimal data available at the time
3/9
Alarmed, they sent President Nixon a letter warning abt the need to prepare for the eventual onset of a new ice age
This made sense given the minimal data available at the time
3/9
This recognition of natural climate change led to a massive increase in data. With that data we now know human emissions of CO2 and methane have broken the planet from its natural glacial/interglacial cycle
All our thermometers show the world is warming at an unnatural rate
4/9
All our thermometers show the world is warming at an unnatural rate
4/9
Natural shifts between ice ages and warmer periods happened slowly. Biological populations (including humans) had time to shift to new terrain
These shifts had a huge impact on ancient humans
With water trapped in ice, lower sea levels let humans expand across the globe
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These shifts had a huge impact on ancient humans
With water trapped in ice, lower sea levels let humans expand across the globe
5/9
Our best evidence for Neandertal use of fire comes during warm periods & not during cold periods (they shivered a lot)
Some archaeologists suggest Neandertals couldn't start fires, but could control natural fires that were more prevalent when warm
sapiens.org/archaeology/ne…
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Some archaeologists suggest Neandertals couldn't start fires, but could control natural fires that were more prevalent when warm
sapiens.org/archaeology/ne…
6/9
The development of agriculture happened in many places around the world. Not coincidentally in all these places it happened soon after the end of the last ice age
Our prehistory and history is tied to climate change
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Our prehistory and history is tied to climate change
7/9
But, right now, we are causing the climate to warm in an extreme way. Really really quickly
The good thing is we now know we are causing this shift. It means we all need to work to stop it
As @KHayhoe says in her TED talk, the most important thing we can do is talk about it
8/9
The good thing is we now know we are causing this shift. It means we all need to work to stop it
As @KHayhoe says in her TED talk, the most important thing we can do is talk about it
8/9
This thread is my way of contributing to today's #climatestrike
A strike from my 1st vacation in 2 yrs
I will craft more threads on the archaeology of ancient climate change. We must learn more abt the relationship b/t humans and past climate change
Our world is beautiful
/End
A strike from my 1st vacation in 2 yrs
I will craft more threads on the archaeology of ancient climate change. We must learn more abt the relationship b/t humans and past climate change
Our world is beautiful
/End
For more on how archaeology can inform our understanding of the long term relationship between humans and their environment, check out "In Defense of (Studying) Food" in @eidolon_journal
eidolon.pub/in-defense-of-…
eidolon.pub/in-defense-of-…
