# Chemical Oceanography

posted by
**josh** on
.

Avg PO4^3- []'s in the deep and surface ocn's are 2.11 and 0.71umolkg^-1. Calc the residence time of PO4^3- in the deep ocn considering the carbon budget(Figure below) Write the general equation, calculation and units.

------ represents a Box outline

Surface---------------------------------

[P]

------------/\--------------==----------

---------\/-----------------==----------

(arrows moving \/(sinking)

up and down through Jc = 5.0Gt/y

surface and deep)

v =4.6 m/y

deep------------==----------------------

----------------==----------------------

\/ (sinking)

Bc = 0.15Gt/y

sediments-------------------------------