Oceanic circulation

• Oceans play an important role in redistributing energy around the globe.
• Oceans hold onto 2/3rds of the suns energy and holds it longer than land does. Ocean currents move this around.
• Ocean current generally goes in the direction of the prevailing (usual) wind.
• The oceans currents have links to the atmospheric cells (Hadley, ferrel and polar).
• Warm currents move warm water (energy) away from equator towards the poles.
• Cold currents move cold water away from the poles towards the equator.
• Gyres are cycles of warm and cold currents that often form loops in large unobstructed bodies of water (oceans).
• Gyres move clockwise in the northern hemisphere and anti clockwise in the southern hemisphere. Due to the coriolus effect.
• Land mass also obstruct currents.
• Thermohaline circulation: Cold salt water is denser so sinks to the bottom of the ocean. Warmer water is less dense so flows into replace the sinking cold water. This cycle repeats as the surface water eventually becomes cold enough to sink.
• Thermohaline circulation: This 'starts' the global conveyer belt which is a connected system of deep and surface currents that circulate around the globe on an 1000 year time span.