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The earth was once 6 degrees warmer according to the geologic record. From what we know, it looked nothing like that map. Edit - here, for people who can't do

The earth was once 6 degrees warmer according to the geologic record. From what we know, it looked nothing like that map. Edit - here, for people who can't do their own homework: https://www.smithsonianmag.com/science-nature/travel-through-deep-time-interactive-earth-180952886/ https://www.smithsonianmag.com/science-nature/travel-through... And: https://en.wikipedia.org/wiki/Geologic_temperature_record https://en.wikipedia.org/wiki/Geologic_temperature_record

goerz 7y ago
Source?
- Mikeb85 7y ago
  Is this a joke? Dunno, grade school? Corroborated by a multitude of sources, some of which are on Wikipedia, and should be general knowledge. Did you not learn about this in grade school?
  - Retra 7y ago
    Is "taught in grade school" your standard of proof?
    - Mikeb85 7y ago
      Some things are common enough knowledge that asking for a source is disingenuous. Everyone should know the earth was once warmer and went through various cooling periods. It's like asking for a source to prove the sky is blue or that the earth is round... This community claims to be one of educated professionals, yet somehow there's comments questioning things that are literally common knowledge and if somehow they don't know, can't spend 2 seconds to google it? Instead write "Source?". It's intellectually lazy as hell.
      - Retra 7y ago
        >Some things are common enough knowledge that asking for a source is disingenuous. Yes. But then we invented science and "common knowledge" was proven ignorant time and time again. >It's like asking for a source to prove the sky is blue or that the earth is round... Hardly. I can't look out my window and see what the temperature was thousands of years ago. >This community claims to be one of educated professionals You're claiming that, not 'the community.' What is intellectually lazy is not providing information that verifies your claims, and instead preferring to debate the social circumstances of an internet discussion. You're not obligated to provide a source. You don't have to do it. But don't think you're somehow more intellectually honest or hardworking because you refuse to. If 2 seconds of googling solves this problem, then you should have probably just done that rather than arguing about whether you should need to.
        Mikeb85 7y ago
        I googled it for the intellectually lazy. As an aside, the reason we know that CO2 affects earth's temperature is the same reason we know what kind of vegetation existed during that same time period. Because of observations in the fossil record.
      - lordCarbonFiber 7y ago
        The problem with things that "everyone knows" is they are often hyper simplified abstractions that form useful models but are not appropriate to discussions of anything specific or for shaping policy. Everyone "knows" Pluto is farther than Neptune (except when it isn't[0]), traits are passed via dna (except when they aren't[1]), sex matches with gender (except it doesn't[2]). Sure the earth was warmer in the past, it was also colder, it was also a molten hellscape. Trying to relate a grade schooler's understanding of geologic time to specific climate models seems to be far more intellectually lazy than asking for a source so people can put your very vague claims into context. [0]https://curiosity.com/topics/pluto-and-neptune-swap-places-every-248-years-curiosity/ https://curiosity.com/topics/pluto-and-neptune-swap-places-e... [1]https://en.wikipedia.org/wiki/Epigenetics https://en.wikipedia.org/wiki/Epigenetics [2]https://en.wikipedia.org/wiki/Sex_and_gender_distinction https://en.wikipedia.org/wiki/Sex_and_gender_distinction
  - goerz 7y ago
    It’s not a joke. What are you talking about? 56 million years ago (Paleocene-Eocene Thermal Maximum, the last time temperatures were six degrees higher? Or, back when earth was a molten rock of lava? That’s completely irrelevant to this discussion. Temperatures haven’t been higher than a degree since the last ice age (see the excellent relevant xkcd: https://www.climatecentral.org/news/climate-change-xkcd-comic-20696 https://www.climatecentral.org/news/climate-change-xkcd-comi...). Rapid anthropogenic global warming does not bode well for human civilization. That doesn’t mean life on earth or humans as a species will be wiped out, but you can’t say “earth was hotter when the dinosaurs were around, so, no problem”
    - Mikeb85 7y ago
      Didn't say no problem, only that the map of the original post I replied to is shit. Which it is. There's no reason to believe everything south of Siberia and Canada will be a desert. Climate science is based on past CO2 levels and uses the fossil record of foliage to estimate temperatures. Not even the most dire predictions claim the earth will be mostly desert in 100 years. There will be flooding and some desertification, but many regions will also become greener. Even NASA has observed that the earth is greener today than 40 years ago.
skinnymuch 7y ago
Do we have map estimates of what it looked like at that time?
- Mikeb85 7y ago
  Sure. This is pretty basic, but here: https://www.smithsonianmag.com/science-nature/travel-through-deep-time-interactive-earth-180952886/ https://www.smithsonianmag.com/science-nature/travel-through... Anyhow, we know from the geologic record of fossils that the world, at it's hottest, had vegetation in most regions. It wasn't 80% desert like the OP I responded to.
  - skinnymuch 7y ago
    I don’t know anything about how the world would change. But me being skeptical of everything being ruined with 4 degree increase doesn’t mean anything. I don’t know much science. Thanks for link. The topic interests me and I’d like to know more.
martin_a 7y ago
How many people lived on earth at that time? And how interwoven was everything they did on a global scale?
SketchySeaBeast 7y ago
> From what we know, it looked nothing like that map. Yes, because at that point it was a map of pangea.
- kaybe 7y ago
  And I'm just starting to learn about the fact that the placement of landmasses massively influences the global climate. We're looking at a very different system here.
- Mikeb85 7y ago
  I posted a map. During the Jurassic, the world was much warmer, greener, and Pangea was already broken up, although the continents weren't in their current positions. They did span from pole to pole however. The point is that the map posted by OP is junk and not based on any science, just alarmist rhetoric.
marcyb5st 7y ago
The key point is how fast the temperature changes. Over several thousands of years that change can be tolerated by the ecosystem (animals and plants evolve over several hundreds of generations and can survive). We already increased the temperature of 1. something degrees Celsius in perhaps a 100 of years and the trend in accelerating. That's way too fast for natural selection to make a difference. So, yeah, Eocene was super warm, but the flora and fauna was well adapted to survive in those conditions. Also, if you don't believe me, look better in the article you linked: https://en.wikipedia.org/wiki/Geologic_temperature_record#/media/File:All_palaeotemps.svg https://en.wikipedia.org/wiki/Geologic_temperature_record#/m... (pay attention to the non uniform time axis...)
- Mikeb85 7y ago
  Not saying there won't be ill effects. But the alarmist idea that the world will be 80% desert isn't based on any science.
  - goerz 7y ago
    How a map at +4 or +6 degrees may or may not look is pretty far from "grade school", and definitely requires sources. I agree that the map in the parent comment doesn't meet my standards for scientific accuracy, due to lack of sources, but that doesn't mean I'd discount it. It's not exactly implausible, extrapolating from current desertification. Seems like the map is from a book (https://www.paragkhanna.com/home/2016/3/9/the-world-4-degrees-warmer?rq=warmer https://www.paragkhanna.com/home/2016/3/9/the-world-4-degree...), so presumably that book would contain explanations. Your Smithsonian map is quite bad, too: It contains no legend, an no explanations at all, although based on the coloring it would seem that there's less desertification than in the parent comment map. But then, it also looks like due to continental drift, the majority of landmass was on the Southern hemisphere. I think it's pretty silly to draw too many conclusions about desertification in the next century from a picture of the earth 170 million years ago, with a completely different distribution of land mass and weather patterns.

goerz 7y ago

Source?

Mikeb85 7y ago
Is this a joke? Dunno, grade school? Corroborated by a multitude of sources, some of which are on Wikipedia, and should be general knowledge. Did you not learn about this in grade school?
- Retra 7y ago
  Is "taught in grade school" your standard of proof?
  - Mikeb85 7y ago
    Some things are common enough knowledge that asking for a source is disingenuous. Everyone should know the earth was once warmer and went through various cooling periods. It's like asking for a source to prove the sky is blue or that the earth is round... This community claims to be one of educated professionals, yet somehow there's comments questioning things that are literally common knowledge and if somehow they don't know, can't spend 2 seconds to google it? Instead write "Source?". It's intellectually lazy as hell.
    - Retra 7y ago
      >Some things are common enough knowledge that asking for a source is disingenuous. Yes. But then we invented science and "common knowledge" was proven ignorant time and time again. >It's like asking for a source to prove the sky is blue or that the earth is round... Hardly. I can't look out my window and see what the temperature was thousands of years ago. >This community claims to be one of educated professionals You're claiming that, not 'the community.' What is intellectually lazy is not providing information that verifies your claims, and instead preferring to debate the social circumstances of an internet discussion. You're not obligated to provide a source. You don't have to do it. But don't think you're somehow more intellectually honest or hardworking because you refuse to. If 2 seconds of googling solves this problem, then you should have probably just done that rather than arguing about whether you should need to.
      - Mikeb85 7y ago
        I googled it for the intellectually lazy. As an aside, the reason we know that CO2 affects earth's temperature is the same reason we know what kind of vegetation existed during that same time period. Because of observations in the fossil record.
    - lordCarbonFiber 7y ago
      The problem with things that "everyone knows" is they are often hyper simplified abstractions that form useful models but are not appropriate to discussions of anything specific or for shaping policy. Everyone "knows" Pluto is farther than Neptune (except when it isn't[0]), traits are passed via dna (except when they aren't[1]), sex matches with gender (except it doesn't[2]). Sure the earth was warmer in the past, it was also colder, it was also a molten hellscape. Trying to relate a grade schooler's understanding of geologic time to specific climate models seems to be far more intellectually lazy than asking for a source so people can put your very vague claims into context. [0]https://curiosity.com/topics/pluto-and-neptune-swap-places-every-248-years-curiosity/ https://curiosity.com/topics/pluto-and-neptune-swap-places-e... [1]https://en.wikipedia.org/wiki/Epigenetics https://en.wikipedia.org/wiki/Epigenetics [2]https://en.wikipedia.org/wiki/Sex_and_gender_distinction https://en.wikipedia.org/wiki/Sex_and_gender_distinction
- goerz 7y ago
  It’s not a joke. What are you talking about? 56 million years ago (Paleocene-Eocene Thermal Maximum, the last time temperatures were six degrees higher? Or, back when earth was a molten rock of lava? That’s completely irrelevant to this discussion. Temperatures haven’t been higher than a degree since the last ice age (see the excellent relevant xkcd: https://www.climatecentral.org/news/climate-change-xkcd-comic-20696 https://www.climatecentral.org/news/climate-change-xkcd-comi...). Rapid anthropogenic global warming does not bode well for human civilization. That doesn’t mean life on earth or humans as a species will be wiped out, but you can’t say “earth was hotter when the dinosaurs were around, so, no problem”
  - Mikeb85 7y ago
    Didn't say no problem, only that the map of the original post I replied to is shit. Which it is. There's no reason to believe everything south of Siberia and Canada will be a desert. Climate science is based on past CO2 levels and uses the fossil record of foliage to estimate temperatures. Not even the most dire predictions claim the earth will be mostly desert in 100 years. There will be flooding and some desertification, but many regions will also become greener. Even NASA has observed that the earth is greener today than 40 years ago.

skinnymuch 7y ago

Do we have map estimates of what it looked like at that time?

Mikeb85 7y ago
Sure. This is pretty basic, but here: https://www.smithsonianmag.com/science-nature/travel-through-deep-time-interactive-earth-180952886/ https://www.smithsonianmag.com/science-nature/travel-through... Anyhow, we know from the geologic record of fossils that the world, at it's hottest, had vegetation in most regions. It wasn't 80% desert like the OP I responded to.
- skinnymuch 7y ago
  I don’t know anything about how the world would change. But me being skeptical of everything being ruined with 4 degree increase doesn’t mean anything. I don’t know much science. Thanks for link. The topic interests me and I’d like to know more.

martin_a 7y ago

How many people lived on earth at that time? And how interwoven was everything they did on a global scale?

SketchySeaBeast 7y ago

> From what we know, it looked nothing like that map. Yes, because at that point it was a map of pangea.

kaybe 7y ago
And I'm just starting to learn about the fact that the placement of landmasses massively influences the global climate. We're looking at a very different system here.
Mikeb85 7y ago
I posted a map. During the Jurassic, the world was much warmer, greener, and Pangea was already broken up, although the continents weren't in their current positions. They did span from pole to pole however. The point is that the map posted by OP is junk and not based on any science, just alarmist rhetoric.

marcyb5st 7y ago

The key point is how fast the temperature changes. Over several thousands of years that change can be tolerated by the ecosystem (animals and plants evolve over several hundreds of generations and can survive). We already increased the temperature of 1. something degrees Celsius in perhaps a 100 of years and the trend in accelerating. That's way too fast for natural selection to make a difference. So, yeah, Eocene was super warm, but the flora and fauna was well adapted to survive in those conditions. Also, if you don't believe me, look better in the article you linked: https://en.wikipedia.org/wiki/Geologic_temperature_record#/media/File:All_palaeotemps.svg https://en.wikipedia.org/wiki/Geologic_temperature_record#/m... (pay attention to the non uniform time axis...)

Mikeb85 7y ago
Not saying there won't be ill effects. But the alarmist idea that the world will be 80% desert isn't based on any science.
- goerz 7y ago
  How a map at +4 or +6 degrees may or may not look is pretty far from "grade school", and definitely requires sources. I agree that the map in the parent comment doesn't meet my standards for scientific accuracy, due to lack of sources, but that doesn't mean I'd discount it. It's not exactly implausible, extrapolating from current desertification. Seems like the map is from a book (https://www.paragkhanna.com/home/2016/3/9/the-world-4-degrees-warmer?rq=warmer https://www.paragkhanna.com/home/2016/3/9/the-world-4-degree...), so presumably that book would contain explanations. Your Smithsonian map is quite bad, too: It contains no legend, an no explanations at all, although based on the coloring it would seem that there's less desertification than in the parent comment map. But then, it also looks like due to continental drift, the majority of landmass was on the Southern hemisphere. I think it's pretty silly to draw too many conclusions about desertification in the next century from a picture of the earth 170 million years ago, with a completely different distribution of land mass and weather patterns.