Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

What does the land under Antarctica’s ice sheet look like?

ubique.americangeo.org

Post reply on HN
Print view View original

61–70 of 83 posts

Re: What does the land under Antarctica’s ice sheet look like?

#61

Post by jeddy3 »

qikInNdOutReply wrote: post #21
nirimda wrote: post #18

Earlier quoted context omitted.

Only because it's at the south pole. If we tilted the earth a bit, it would warm up and start raining. But if we tilted the earth a bit, Australia could probably also get wetter. As far as I understand it, the dryness of Australia, the Sahara etc are caused by the particular location from the equator, where moist air is lifted and brought to the equator and dumped there as rain. So if we pushed Australia further from…

The evidence does not seem to follow this logic. There are lots of countries closer to the equator - they are wetter.. large body masses have continental clima, which enocourages the growth of dessert, but they usually do so only when the war of forrest vs savannah is lost by the forrest. Which can cling to areas quiet defiantly, for example the last big forrests in syria, that once covered the middle east

To be fair, they said particular location from the equator.

Does not have to mean close to the equator.

Re: What does the land under Antarctica’s ice sheet look like?

#62

Post by NKosmatos »

platz wrote: post #19

Why is there land at all at the south pole? Can't just be coincidence.

Well, land is heavier than water so it drops to the bottom of the earth (South Pole) whereas there is nothing at the top of the earth (North Pole), just water and ice. (Joking obviously, I’m not a flat/hollow-earther or anything similar)

Re: What does the land under Antarctica’s ice sheet look like?

#63

Post by kevin_thibedeau »

telesilla wrote: post #41
cwmma wrote: post #28

Earlier quoted context omitted.

I mean it's what the content would look like for a long time, Scandinavia is still not done rising from the last glacial period.

Are there earthquakes or other events that are recognized on a human scale?

Yes. The entire northern lattitudes have quakes (typically mag 1-3) from ongoing post-glaciation uplift.

Re: What does the land under Antarctica’s ice sheet look like?

#64

Post by Zash »

telesilla wrote: post #41
cwmma wrote: post #28

Earlier quoted context omitted.

I mean it's what the content would look like for a long time, Scandinavia is still not done rising from the last glacial period.

Are there earthquakes or other events that are recognized on a human scale?

Yes, small ones. http://www.snsn.se/map_right.html lists earthquakes in Sweden the last year.

Re: What does the land under Antarctica’s ice sheet look like?

#65

Post by rr888 »

jl6 wrote: post #5

Note that this isn’t necessarily what the continent would look like if all the ice melts. The lack of ice weight would allow the land to rebound upwards: https://polarjournal.ch/en/2022/07/13/what-greenland-and-ant...

Also Greenland and Antartica have so much ice it produces a gravitational pull on the surrounding water. Its one of the reasons sea levels rise in most of the world when that gravity weakens and water is redistributed.

Re: What does the land under Antarctica’s ice sheet look like?

#66

Post by addaon »

SketchySeaBeast wrote: post #35
jameshart wrote: post #32

Earlier quoted context omitted.

30% of the surface is land. But only 15% of land has land antipodal to it, which certainly initially feels like less than you would expect by random chance. It’s easy to fall into some counterintuitive fallacies reasoning about this though because we’re considering a spherical surface pairwise and you might be tempted to say ‘ah, but we’re counting the antipodal land twice so that probably accounts for the 15%/30% th…

Just for curiosities sake I fell down the rabbit hole and ran the numbers (please someone correct me if I'm wrong on this - it's been a loooooong time since I did statistics). This is all assuming some sort of even distribution of land/water, so the numbers don't reflect real world continental distribution, but I don't know how to account for that. We have a 30% chance of picking a random point on Earth and getting l…

> We have a 30% chance of picking a random point on Earth and getting land. Because earth is so big and these theoretical points are so small I'm going to assume that one point of land existing doesn't effect the odds of another piece of land existing.

This is the issue.

A large contributor of the "point antipodal to land is water" anomaly is the typical size of land masses. If, for example, the average size of land masses was 30% of earth's area, then we'd have a single large land mass (Pangaea style), and all antipodal points would be water.

The approximation of independence here doesn't reflect reality. Eurasia alone is more than 10% of the land area of Earth.

Re: What does the land under Antarctica’s ice sheet look like?

#68

Post by gorgoiler »

jameshart wrote: post #23
platz wrote: post #19

Why is there land at all at the south pole? Can't just be coincidence.

But there’s none at the North Pole. One pattern that is curiously consistent is that broadly land tends to be antipodal to ocean (and not just because there’s more ocean in general - there’s a genuine statistical skew) - so having land at one pole and none at the other matches that overall pattern. ( https://www.geodatos.net/en/antipodes ) Basically a surprisingly large proportion of antipodal pairs have land at one…

The North Pole isn’t far off being land. A lot of the Arctic Sea is only slightly underwater.

https://commons.m.wikimedia.org/wiki/File:IBCAO_betamap.jpg

Re: What does the land under Antarctica’s ice sheet look like?

#69

Post by ErikCorry »

hackerman123469 wrote: post #4

I wonder if the locations researchers are staying at are located on top of the land or if it's just randomly located and could be either. Like if all (or a majority of) the ice melted how big of an impact would it have on the locations?

What about the actual South Pole? Looks like it might be over water.

Re: What does the land under Antarctica’s ice sheet look like?

#70

Post by sanj »

rr888 wrote: post #65
jl6 wrote: post #5

Note that this isn’t necessarily what the continent would look like if all the ice melts. The lack of ice weight would allow the land to rebound upwards: https://polarjournal.ch/en/2022/07/13/what-greenland-and-ant...

Also Greenland and Antartica have so much ice it produces a gravitational pull on the surrounding water. Its one of the reasons sea levels rise in most of the world when that gravity weakens and water is redistributed.

Do you have a link to an article explaining this?
Post reply on HN