I'm mostly interested in what the more hardcoe lore buffs have to say on this.

It's commonly held, at least I've seen, that Aldmeri does not in fact exist and never has. A handful of books suggest this, although some of which can be written off as Imperial propaganda.

At the same time, though, Atmora also stands as a place of questionable validity. In fact, the NM interecept letter 5, one of the references used to suggest that Aldmeri did not exist, says that ALL mortal life started on tamriel.

Could many of the stories about Atmora be the same collection of visions that are held as the basis of Aldmeri? Given the TES has always been imperial centric series, with the empire often highlighted as a positive force, it makes sense why we would have more references on Atmora. And given its significance to the story of Talos/Tiber/Hjalti, is not surprising we have so many references.

So can we say for sure Atmora exists?

The difference being, Nord creation myths state that they were created on Tamriel, migrated to Atmora, then came back. I would say it does exist.

As far as I know, but I am not 100% sure and people may correct at all times, there have been expeditions to old Atmora.
It appears to be a land filled with ice-wraiths and ice-undead but I am really unsure as to where I got these ideas from.

I am relatively sure though that Atmora is 'real' though I think the notion that like Aldmeris it is more an idea(l) than an actual place is very interesting.
One can say that no-ones history truly began until they arrived/ returned to Tamriel.
None that the races deem to be important anyway.

There are no Nord creation myths. Only old Nord stories.

Reference link? Never read that before. Mind you I don't doubt you more so that I'm very curious about this.

http://www.uesp.net/wiki/Skyrim:Children_of_the_Sky

Throat of the World

This is the highest mountain in Skyrim, and the highest in Tamriel aside from Vvardenfell in Morrowind. The Nords believe men were formed on this mountain when the sky breathed onto the land. Hence the Song of Return refers not only to Ysgramor's return to Tamriel after the destruction of Saarthal, but to the Nords' return to what they believe was their original homeland. Pilgrims travel from across Skyrim to climb the Seven Thousand Steps to High Hrothgar, where the most ancient and honored Greybeards dwell in absolute silence in their quest to become ever more attuned to the voice of the sky.

From the First Pocket Guide.

Well there is that too

I'd like to say something like "Atmora is a bit of the last kalpa the Dragon missed, and the Nords going there and coming back is a metaphor for time-travelling knarr built from lost techniques and the driving of Man from Dawn's Beauty was an exodus not only from the continent but from the entire kalpa" but there's no support for any explanation but the mundane.

I may be wrong here, but aren't the Raiders (with their strength draining axes) in Solstheim (Bloodmoon) described as coming from Atmora?

What about the Redguards?
Hmm:

What I really want to know is why Atmora freeeeze?

A http://img254.imageshack.us/img254/7374/skyrimmk.jpg from the MK, taken from the Aldudagga Fight Four thread.

Are you implying a Numidium-like creature made it uninhabitable?

Not really, but that sounds like a grand idea.

Global cooling?

Talos is waving goodbye, Atmora is moving on to the next kalpa.

I'm pretty sure that's a giant. Note the swirls

Or is it KINMUNE round 2?

i don't really get it.

nords live in skyrim.
nords are ruled by dragons.
nords defeat dragons
(akarvir people do something i never quite understood here?)
nords go to atmora,
atmora freeze over
nords come back, kill the falmer.
nords settle for good in tamriel.

sounds odd.

Cause you've got it in the wrong order.

Nords, along with everyone else, start out on a proto-continent, of which Tamriel is part.
Through splitting of continents and migration, Nords end up on Atmora.
Nords worship animal pantheon. Atmora begins to freeze over.
Nords begin return to Skyrim, bringing animal pantheon with them.
Nords kill Falmer.
Dragon cult takes prominence, eventually dominating the Nords.
War with Dragons. Nords learn Thu'um, Alduin banished, Dragon Cult overthrown.
Nords kill Falmer some more.

I never read anywhere that Atmora froze over (don't Nords have frost immunity/resistance anyway), Skyrim's "Dragon War" book seemed to suggest that the Nords migrated to escape the dragon priests' political influence.

The http://imperial-library.info/content/pocket-guide-empire-third-edition-atmora says it clearest. They're really not exclusive: http://imperial-library.info/content/frontier-conquest-and-accommodation also claims that civil war was a reason for immigration.

the rest of the fauna and flora wouldn't of.

thanks for that N!