primary_prod

 PI:              Richard Barber,  Duke University     
                         John Marra, Lamont Doherty Earth Observatory
                         Walker Smith, Virginia Institute of Marine Science
 technician:      Michael Hiscock, Duke University
 dataset:         Primary Production, incubated in situ, 24 hours
 project/cruise:  AESOPS/NBP-97-3  - Ross Sea Process Cruise 3
 ship:            Nathaniel B. Palmer
 
 Methods reported in:
   - Please see Chapter 19 of the JGOFS protocols (1994) "Primary Production by 14C"
   - Barber, Richard T. 1993. In Situ Primary Production Protocols.
     U.S. Joint Global Ocean Flux Study - Equatorial Pacific Protocols, 1993, section 7.
   - Smith, W. O., Jr., R. T. Barber, M. R. Hiscock and J. Marra (submitted)
        The Seasonal Cycle of Phytoplankton Biomass and Primary Productivity
          in the Ross Sea, Antarctica.   Deep-Sea Research II.
   - Barber, R. T., L. Borden, Z. Johnson, J. Marra, C. Knudsen, and C.C.Trees (1997)
        Ground truthing modeled kpar and on deck primary productivity incubations with
          in situ observations. SPIE 2963, 834-839.
   - Barber, R. T. and F. P. Chavez (1991) Regulation of primary productivity rate
          in the equatorial Pacific Ocean.  Limnol. Oceanogr. 36, 1803-1815.
   - Morel, A. (1988) Optical modelling of the upper ocean in relation to its biogenous
          matter content (Case 1 waters).  Journal of Biophysical Research 93, 10749-10768.


 Parameter          Description                                               Units

 event              event number, from event log
 sta                station number, from event log
 cast               cast number, from event log 
 sta_name           name of revisited locations on AESOPS cruises
 cast_type          TM = trace metal rosette
                    CTD = CTD rosette
 bot                Goflo or Niskin bottle number
 depth_n            nominal depth sampled by Goflo or Niskin                  meters
 chl_a              chlorophyll_a as measured by fluorometric method          mg Chl m-3
 chl_a_int_depth    depth to which chl_a is integrated                        meters
 chl_a_int          integrated from 0 meters to the depth of the deepest      mg Chl m-2
                      sample bottle (chl_a_int_depth)
 depth_in_situ      depth where samples were incubated in situ                meters
 pp24               primary production, carbon assimilation (24 hours)        mmol C m-3 d-1 
 pb24               carbon assimilation per unit chl_a (24 hours)             mmol C mg Chl-1 d-1
 depth_1            depth of 1% light level based on Morel optical model      meters
                     Note:  To eliminate individual, ship and cruise 
                     dependent sources of variability in the estimation
                     of kpar and assignment of light depths Andre Morel's
                     optical model is employed (Morel, 1988; Barber et.al.
                     , 1997).  The model estimates the profile of light
                     extinction based on a profile of extracted chlorophyll
                     concentrations.  The Morel light profile is helpful
                     in comparing on deck vs. in situ primary production
                     integrations.  
 pp24_int_1         primary production, carbon assimilation (24 hours)        mmol C m-2 d-1
                     integrated from 0 meters to the depth of the 1% light
                     level based on Morel optical model (depth_1%)
                     Note: 1% light level productivity was interpolated
                     or extrapolated from the in situ productivity profile.
 depth_0.1          depth of 0.1% light level based on Morel optical model    meters
 pp24_int_0.1       primary production, carbon assimilation (24 hours)        mmol C m-2 d-1
                     integrated from 0 meters to the depth of the 0.1% light
                     level based on Morel optical model (depth_0.1%)
                     Note: 1% and 0.1% light level productivity values
                     were interpolated or extrapolated from the in situ
                     productivity profile.
 pp24_opt           optimum primary production for profile, carbon            mmol C m-3 d-1
                     assimilation (24 hours)
 pb24_opt           optimum carbon assimilation per unit chl_a                mmol C mg Chl-1 d-1
                     for profile (24 hours)