4 ms·

Palm trees 'grew on Antarctica'

27 points by Zenst 14y ago

hxf148 14y ago
Gets me thinking of the probably unique animals that would have evolved there.
- se85 14y ago
  Who knows? Maybe a large part of us came from there.
- ordinary 14y ago
  Episode 5 of Walking with Dinosaurs was dedicated to Antarctica. Their setting is another 50 million years earlier, as the title implies, but it may interest you nevertheless.
premasagar 14y ago
Evidence of a shift in the geographical poles some time in the past?
- grey-area 14y ago
  In terms of geology/geography, 50MYA is not long ago really - the land masses were broadly similar to those today, and the poles probably were too: http://en.wikipedia.org/wiki/File:Paleogene-EoceneGlobal.jpg http://en.wikipedia.org/wiki/File:Paleogene-EoceneGlobal.jpg So it's more that the climate was dramatically different over the entire globe, with more CO2, and a dramatically higher temperatures, with sub-tropical poles.
  - premasagar 14y ago
    To clarify, I wasn't so much thinking of continents drifting relative to each other, rather something like the Earth's crust slipping on the molten mantle so that the continents all moved together from equator to pole and vice versa. I remember hearing some potential evidence for this (but don't have any links to hand).
tjic 14y ago
This strongly suggests that the idea of "run away" greenhouse effect, wherein the Earth latches into a permanent irreversible hotter state ("like Venus", the media was saying back in the 80s and 90s) is not true: the Earth has been 10-20 degrees F warmer in the past and has declined from there.
- TimJRobinson 14y ago
  Yea its been known for a long time that that was the case. The problem with modern climate change is the speed at which its changing. In the past plants and animals evolved to deal with changes as they appened over millions of years, and now they have to adapt in just a few decades which is impossible for most.
- andyjohnson0 14y ago
  Obviously the earth hasn't latched into a "permanent irreversible hotter state". The present climate and the fact that we even exist to talk about it demonstrates that. What exactly are you trying to say? And the fact that the earth is cooler now than at some arbitrary time(s) in the past doesn't prove that such a state isn't possible either, only that it hasn't happened yet. The earth was 5-10 degF warmer in the Middle Miocene, about 15-20 million years ago. Inferring from this that global temperatures are following a declining trend is extremely misleading.
  - tjic 14y ago
    > Obviously the earth hasn't latched into a "permanent irreversible hotter state". The present climate and the fact that we even exist to talk about it demonstrates that. What exactly are you trying to say? There are two ways that we might not have latched into a runaway greenhouse effect: 1) the effect exists with a trigger temperature, and we have never hit that trigger temperature 2) the effect does not exist. The fact that Antarctica has been tropical and is not now suggests that #1 is false. > Inferring from this that global temperatures are following a declining trend is extremely misleading. WHERE did you get the belief that I was suggesting that? All I said was that apparently there is not an unrecoverable latch-up in the next 10-20 degrees.
- 14y ago

27 points by Zenst 14y ago

hxf148 14y ago

Gets me thinking of the probably unique animals that would have evolved there.

se85 14y ago
Who knows? Maybe a large part of us came from there.
ordinary 14y ago
Episode 5 of Walking with Dinosaurs was dedicated to Antarctica. Their setting is another 50 million years earlier, as the title implies, but it may interest you nevertheless.

premasagar 14y ago

Evidence of a shift in the geographical poles some time in the past?

grey-area 14y ago
In terms of geology/geography, 50MYA is not long ago really - the land masses were broadly similar to those today, and the poles probably were too: http://en.wikipedia.org/wiki/File:Paleogene-EoceneGlobal.jpg http://en.wikipedia.org/wiki/File:Paleogene-EoceneGlobal.jpg So it's more that the climate was dramatically different over the entire globe, with more CO2, and a dramatically higher temperatures, with sub-tropical poles.
- premasagar 14y ago
  To clarify, I wasn't so much thinking of continents drifting relative to each other, rather something like the Earth's crust slipping on the molten mantle so that the continents all moved together from equator to pole and vice versa. I remember hearing some potential evidence for this (but don't have any links to hand).

tjic 14y ago

This strongly suggests that the idea of "run away" greenhouse effect, wherein the Earth latches into a permanent irreversible hotter state ("like Venus", the media was saying back in the 80s and 90s) is not true: the Earth has been 10-20 degrees F warmer in the past and has declined from there.

TimJRobinson 14y ago
Yea its been known for a long time that that was the case. The problem with modern climate change is the speed at which its changing. In the past plants and animals evolved to deal with changes as they appened over millions of years, and now they have to adapt in just a few decades which is impossible for most.
andyjohnson0 14y ago
Obviously the earth hasn't latched into a "permanent irreversible hotter state". The present climate and the fact that we even exist to talk about it demonstrates that. What exactly are you trying to say? And the fact that the earth is cooler now than at some arbitrary time(s) in the past doesn't prove that such a state isn't possible either, only that it hasn't happened yet. The earth was 5-10 degF warmer in the Middle Miocene, about 15-20 million years ago. Inferring from this that global temperatures are following a declining trend is extremely misleading.
- tjic 14y ago
  > Obviously the earth hasn't latched into a "permanent irreversible hotter state". The present climate and the fact that we even exist to talk about it demonstrates that. What exactly are you trying to say? There are two ways that we might not have latched into a runaway greenhouse effect: 1) the effect exists with a trigger temperature, and we have never hit that trigger temperature 2) the effect does not exist. The fact that Antarctica has been tropical and is not now suggests that #1 is false. > Inferring from this that global temperatures are following a declining trend is extremely misleading. WHERE did you get the belief that I was suggesting that? All I said was that apparently there is not an unrecoverable latch-up in the next 10-20 degrees.
14y ago