As if materializing from a different dimension, the submersible device called PELAGRA slips below the surface and sinks into a research pool at the National Oceanography Centre, in Southampton, England.Soon, two such devices will be deployed to the South Atlantic to collect samples of so-called ‘marine snow.’Marine snow is composed of dead phytoplankton which sort of clump together to form flakes and then they're heavy enough to sink down into the deep ocean.It can also be formed by little animals which eat the little plants and then they poop out that carbon, and then their fecal pellets are very heavy and they sink down to the bottom of the ocean, also carrying lots of carbon with them.Although invisible to the naked eye, phytoplankton are so abundant that they are responsible for half of all the carbon absorbing photosynthetic activity on earth.Understanding that process could help scientists create more advanced computer models of global environmental changes.The challenge was to build a submersible device that could float between 50 and 500 meters deep.That's where scientists say all this carbon is being absorbed, and beginning its journey to the bottom of the sea.The way that we do that is by putting them in tanks of water like this and adding weights until they're just sinking; at which point we know they have the same density as the water that they're sitting in.
