As it would happen, the Great Ice Plateau is a very large and deep wall of ice. It exists in all places north of the eighty-sixth parallel, and its effects are spread far and wide over the northern parts of Terra Alta and the lands directly below. It casts the North Shadow on the Shadowlands.
During the past 70 million years, Terra Alta has this giant block of ice covering over twenty continuities. This is formed because the lands at the Shadowlands begin to form a tropical supercontinent, allowing CO2 to drop immensely and begin to freeze the higher lands. As floatquakes push the land on the Shadowlands to Terra Alta, the ice field is reinforced and thickened.
This creates a disastrous chilling effect all over the planet, and many species at the time begin to form ways to keep the cold out (wink wink). When the sapient species came around some time −900 000 CE, there was a period of sudden freezing that brought the Plateau all the way down to 67° N – very intolerable. It was bad enough that the Shadowland's appropriate ice cap extended to beyond 70° N – as paleomagnetic data shows, this is unprecedented in the past 230 000 000 years or so.
This quick cooling spurred the mass burning of many forests, brought on by the brave men and women wishing to create heat. A lot of early discoveries revolve around getting warm – furnaces, ovens, and water-based/metal-based central heating!
This means that a lot of civilizations are driven south as well. The Qasttega, ancestors of the Qasti, lived in the Kega Continuities before they are pushed off the continuities by the invading Kega Tongue, along with wild hiphons living in the nearby continuities of Saisoga. For this reason, they formed symbiotic relationships with the Qasttega, resulting in Axenbrons.