CODAS conventions

1. All times are in UTC
2. The decimal day is a zero-based value. Noon January 1 UTC is 0.5, not 1.5. This is the best convention when dealing with data that may cross over a year boundary. (if your cruise does cross over a year boundary, the decimal days will just keep increasing past 365)
3. Data averaged over a period of time have an associated time and position. These represent the values at the end of the ensemble. Other scalars associated with a given ensemble (temperature, heading) are averaged.
4. Pitch and roll (if available) are recorded but not used in the data processing.