APFZ_mixed_layer

 PI:              John Morrison
 of:              North Carolina State University
 dataset:         APFZ Mixed Layer Depths
 project/cruise:  AESOPS/KIWI6 - APFZ Survey Cruise 1
                         KIWI7 - APFZ Process Cruise 1
                         KIWI8 - APFZ Survey Cruise 2
                         KIWI9 - APFZ Process Cruise 2
 ship:            R/V Roger Revelle

 Note:  event 02162111 salts were bad, therefore density was not computed.
        Some station casts were not deep enough to show a mixed layer.

 Parameter        Description                                     Units

 cruise_id        cruise ID number
 cruise_type      process cruise or survey cruise
 event            event number, from event log
 sta              station number, from event log
 cast             cast number, from event log
 date             date as YYYYMMDD
 time             time of day                                     decimal hours
 yrday            day of year where midnight, Jan 1 = day 1
 lat_n            nominal latitude (- = south, + = north)         decimal degrees
 lon_n            nominal longitude (- = west, + = east)          decimal degrees
 MLD_0d01_dp      mixed layer pressure                            decibars
                    delta potential density from surface = .01
 MLD_0d02_dp      mixed layer pressure                            decibars
                    delta potential density from surface = .02
 MLD_0d05_dp      mixed layer pressure                            decibars
                    delta potential density from surface = .05
 CTD_top_db       pressure of first reported CTD observation      decibars
 MLD_0d01_d       mixed layer depth                               meters
                    delta potential density from surface = .01
 MLD_0d02_d       mixed layer depth                               meters
                    delta potential density from surface = .02
 MLD_0d05_d       mixed layer depth                               meters
                    delta potential density from surface = .05
 CTD_top_m        depth of first reported CTD observation         meters