From last class we learned that different ocean layers stratify in this ocean, in part due to a given body of water’s salinity. This class we learned how temperature affects water density too! The ocean has a cyclical conveyor-belt like body of flowing water within it, so called deep ocean currents. These currents are responsible for many of the climatic environments we are used to today, for example the Gulf Stream is responsible for much of the relatively mild weather we enjoy around the northern Atlantic. Part of what drives this global temperature regulating mechanism (the Gulf Stream specifically but with analogues elsewhere) is the cold dense waters around Greenland that drive the now cooling stream deep down into the deep ocean, perpetuating part of the cycle these deep ocean currents.

To visualize this phenomenon we made ice cubes dyed with food coloring. We dipped the ice cubes in a tilted jug of warm water and they got to watch the flow of the cold colored ice-cube-water. We observed that the streaks of color from the ice tended to flow steadily downwards, staying close to the lower topography of the water jug, before eventually mixing throughout the rest of the container.

We finally closed by touching on how global climate change may disrupt this deep ocean energy-redistributing current. Some scientist think this was a major driver of the last ice age, and claim we are poised to repeat that scenario.