In the ocean surrounding Antarctica, there are fish that survive the cold water by using a molecule made
of glycoproteins that circulates the blood and keeps it
from freezing. Certain kinds of worms that live in the
Arctic Ocean also make antifreeze proteins that help
them live in icy water

Typically currants flow clock wisein northern hemisphere and counter clockwise in the southern hemisphere. ocean currants transport cold water from the poles and back to the tropics and visa versa.  currants regulate the global climate with out currants temps would be unbareable super hot at the equator and too fridged at the poles. making much less of earth land liveable for us. 

climate change increases temps in the ocean