The ship has reported deep, unhappy phytoplankton associated with deep chlorophyll maxima. Inspired by some comments by MJP, this figure attempts to catagorize these maxima in terms of physical and biological transport.

The top panel is glider chlorophyll. The major deep maxima are circled. The bottom panel is glider Oxygen (from Optode), with the same 'circles'. Those marked by an S (for subduction) have a deep oxygen also. One can explain these by advection of surface water downward. Those marked by a K (for sinKing) do not have an oxygen maximum. One can explain these by sinking of unhappy cells.

Of the 9 deep chlorophyll maximum, 6 have oxygen maximum (physical transport) and 3 do not (Sinking).

Should be interesting to see if we can figure out why. Note that these features are only one or two dives wide. Just like the surface features, the sinking is strongly modulated on the 10km scale, probably by the eddy field.