pkg/dic/DIC_VARS.h and pkg/dic/bio_export.F

[christophernhill]

Two small things that could be fixed at some point

1. bioac in the routine below is an output (O), not an input (I).

   C !INTERFACE: ==========================================================
     SUBROUTINE BIO_EXPORT( PTR_PO4 ,
   #ifdef ALLOW_FE
    I           PTR_FE,
   #endif
    I           bioac,
    I           bi,bj,iMin,iMax,jMin,jMax,
    I           myIter,myTime,myThid)

2. the DIC_VARS.h defines a whole load of interesting arrays in some common blocks (e.g. COMMON /BIOTIC_NEEDS/, COMMON /CARBON_CHEM/). There are very few comments explaining what these are.

[seamanticscience]

Some of these variable names could do with some cleaning up, for example:

• the closely named "ak0" the carbon chemistry coefficient, and "k0" the light attenuation coefficient.
• "fesedflux_pcm" and "FeIntSec" determining the iron flux from sediments (Fe_flux = fesedfluxpcm*pflux + FeIntSec) should surely be consistently named, e.g. fesedflux???.

[stephdut]

Looks great! Thank you @seamanticscience

[edoddridge]

Closed by #83