Since such cold water is present in both the polar oceans and deep seas (approximatel 2000 meters in depth), both polar cold water biota and deep sea cold water biota are differentiated.

• 通常这样的冷水体存在于极区的海洋及任何海洋之深处（约超过2000公尺）。所以冷水生物群又可再细分为极区冷水生物群及深海冷水生物群二类。