Tropospheric Chemistry: Measurements

Data Format

ICARTT File Format Standards PDF file (V1.1 updated March 2013)

The ICARTT format was created to standardize data files to facilitate data exchange and to promote ease of use of these files. This format includes information for headers which describe the data presented (meta data), as well as the actual data. This format has been adopted and developed by the Tropospheric Chemistry research group and it is expected that PIs participating in major field studies will use this format. More information


ICARTT file format check (authentication required)


Common pitfalls in making ICARTT files:

  • Time format should be cumulative seconds from midnight on the date the data begins
  • The data should be comma-delimited
  • In the filename and the header, preliminary data is indicated using letters (RA, RB, etc.) and final data uses numbers beginning at 0 (R0, R1, etc.)
  • The filename should be of the form dataID_locationID_YYYYMMDD_R#.ict
    • dataID: short description of measured parameter/species, instrument, or model (e.g., O3; RH; VOC; PTRMS; MM5)
    • locationID: short description of site, station, platform, laboratory or institute
    • YYYYMMDD: The date that the data begin, not the date of data reduction or revision
    • The underscore is used ONLY to separate the different fields of the file name