As sea ice recedes and global temperatures increase, the warm waters of the Atlantic are slowly infringing on the colder waters of the Arctic.
Scientists call this the 'Atlantification' of the Arctic, and it's a serious problem
A new video from Vox explores how 'Antlantification' makes the Arctic Polar Cod particularly vulnerable to species invasion.
There are huge differences between Atlantic and Arctic waters. The Atlantic, for instance, is much saltier and mostly lacks ice.
But the biggest difference is that Atlantic waters are about seven degrees warmer.
Obviously, this influx of warm water has serious repercussions for the Arctic ecosystem.
As Atlantic waters move north, the habitat of the Arctic Polar Cod, which loves cold water, is slowly shrinking.
And, along with the warmer waters, come a whole variety of Atlantic fish. Now, the Arctic Polar Cod not only has a decreased habitat, it also has to compete with southern species to catch its prey.
As a result, Polar Cod numbers in the region are dwindling, while the numbers of Atlantic Cod are increasing.
During a fishing expedition featured in the Vox video, about 70 percent of the fish captured in the Arctic were southern species.
With the invasion of southern Antlantic species, the entire Arctic food chain has been disrupted.
Arctic Polar Cod usually eat tiny copepods, which help them store fat to survive the winter temperatures. This, in turn, makes Arctic Polar Cod a high-energy source for bigger predators.
But Atlantic Cod are not as fatty, which means they do not provide as much energy for predators further along the food chain, like Polar Bears.
This knock on effect has put the whole ecosystem out of whack.
All of this means that as the climate continues to change, so too will the meaning of the word Arctic.