P2OA data are categorized in levels corresponding to processing or validation steps. Corresponding treatments should be specified by the PI in the accompanying metadata file.
The following rules should be considered by the PIs while assigning a level to a dataset :
- Level L0: instrument raw data, access restricted to PIs.
- Level L1A: pre-processed and/or filtered physical instrument variables (e.g. voltage) — not a geophysical variable.
- Level L1B: processed physical instrument variables (e.g. voltage) — not a geophysical variable.
- Level L2A: tentative geophysical variable (to be used cautiously for scientific purposes).
- Level L2B: consolidated geophysical variable (e.g., fully validated, calibrated, etc.).
- Level 3: synthetic geophysical variable (e.g. regridded data).
- Level 4: geophysical variable from numerical modelling, or composed from several observation instruments.