Biogeochemical data: AT32, AT34, AT38, AT39-06 
   N. Atlantic, Nov. 2015, May 2016, Sep 2017, Mar/Apr 2018 
   PI: C. Carlson (UC-SB) 
   version 2 date: 2020-09-14 [revised and add AT39-06] 
 	replaced version: 2019-01-02 [revised AT34 and add AT38] 
        replaced version: 2017-12-01 [reduced depth precision to 0 decimal places] 
        replaces version: 2016-09-19 (added nutrient data and all AT34 data)