Subject: How much 02 released in ocean water reaches the atmosphere?

In various answers on your site regarding photosynyhesis and phytoplankton it is 
not clear how oxygen released during photosynthesis reaches the atmosphere.  It 
appears that the majority of the free oxygen we breath comes from green leafed 
plants during the first phase of photosynthesis.  However, one of your messages 
(915742176.Bt) says that "most of our oxygen comes from photosynthesis in the 
ocean."  If so is it processed by photodissociation or released directly in some 
manner?  I am trying to confirm that approximately 15% of the free oxygen we 
breath comes from ocean photosynthesis and that of the 85% produced by green 
leafy plants approximately 45% is produced by tropical rainforests.  Can you 
help me? 

Re: How much 02 released in ocean water reaches the atmosphere?