elapsed days since Jan 1, 0s

(note: 15th is 0s into 15th day of month)
 
month     mid    15th of month, 0 elapsed sec
-----  ------  ------
    1    15.5    14.0
    2    45.0    45.0
    3    74.5    73.0
    4   105.0   104.0
    5   135.5   134.0
    6   166.0   165.0
    7   196.5   195.0
    8   227.5   226.0
    9   258.0   257.0
   10   288.5   287.0
   11   319.0   318.0
   12   349.5   348.0


bs1201en> ncdump -v time,date,datesec ocn/hurrell_sst_ifrac_1x1_050606.nc
   float time(time) ;
      time:long_name = "time" ;
      time:units = "days since 0001-01-01 00:00:00" ;
      time:calendar = "noleap" ;

   time    =  15,  44,  74, 104, 135, 165, 196, 227, 257,  288,  318,  349 ;


   date    = 116, 214, 316, 415, 516, 615, 716, 816, 915, 1016, 1115, 1216 ;
   datesec =   0,   0,   0,   0,   0,   0,   0,   0,   0,    0,    0,    0 ;