Amasia: a possible northern supercontinent
In the polar Amasia scenario, most continents gather at northern latitudes. Closure of the Arctic region plays an important role. This is not simply another Pangaea placed on the equator, but a different geometry for a future continental assembly.
See polar Amasia 200 million years ahead. Antarctica remains separate in this version. Saying that every continent gathers at the North Pole therefore does not accurately describe the map shown here.
The idea of orthoversion
Mitchell, Kilian and Evans (2012) proposed that successive supercontinents could form about a quarter of the way around the globe from their predecessors. They named the mechanism orthoversion. The hypothesis relates the new assembly's location to a large subduction system and mantle circulation.
This differs from closing an ocean created by the previous breakup, or assembling continents on the opposite side of Earth. It does not establish a universal clock that shifts every successive supercontinent by precisely the same angle.
What does our version show?
Davies, Green and Duarte (2018) developed the polar concept within a set of comparable scenarios. Its endpoint gathers the landmasses except Antarctica into a northern group. Today's great oceans do not disappear entirely as they do in the Aurica scenario.
On a flat map, proximity across the pole can be difficult to judge. Switch to the globe and rotate towards the north. The map edge and stretching at high latitudes are properties of the projection, not extra distance between continents.
Why can Amasia mean a different map?
Huang, Li and Zhang (2022) also use the name Amasia, but investigate assembly through Pacific closure. Their geodynamic models examine factors including the properties of oceanic lithosphere. They do not provide the same trajectories as the polar animation on this site.
Comparisons therefore require checking the authors, mechanism and geometry. A shared name does not guarantee agreement. Our map shows the Davies grids and does not substitute Huang's simulation behind the same button.
Would a northern supercontinent have to be icy?
Latitude alone cannot answer that question. Research described by NASA GISS shows the importance of factors such as surface elevation in Amasia simulations. Climate also depends on the atmosphere, solar radiation and the oceans.
Colours in the tool therefore do not represent ice or vegetation. They only distinguish land from shelves. Compare polar Amasia with low-latitude Aurica and Pacific-closing Novopangea. Their differences are questions to investigate, not four simultaneously valid forecasts.