NetCDF (Network Common Data Format)

GOLD data products are written in NetCDF file format and are not human-readable. Information about NetCDF is available on the Unidata web site. A list of third-party software that can be used to manipulate or display NetCDF data is available on Unidata’s NetCDF software page.

GOLD NetCDF reader for IDL

The IDL procedure below can be used to read GOLD L1C and L2 data files into IDL:

Stellar Occultation Timing Error Correction

The onboard clock is used to assign UT time stamps to individual measurements during GOLD data processing. For stellar occultation observations, these time stamps are then used to generate geolocation for the target star as it passes through the GOLD slit. Because the onboard clock time drifts relative to true time, this can cause an error in the slant path tangent altitude grid assigned to the L1C OCC data. This error then propagates through to the L2 O2DEN data.

The “gold_time_deltas.csv” file below includes the average clock drift (in msec) over 15-minute increments as a function of UTC time. To first order, the error in tangent altitude can be corrected through the use of this known clock drift. See the GOLD Data Release Notes on the documentation page or the “gold_time_deltas.pdf” file below for additional details on how to peform the correction.