IBFV1.11 INTERMAGNET Baseline Format (data 2008 before)

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This format is to be used to provide samples of baselines for use in examining equipment performance and for inclusion on the INTERMAGNET CD-ROM/DVD. The first section contains the observed baseline values on those days on which they were measured. Consequently the number of entries will depend upon the schedule for absolute measurements at that observatory. The second section contains adopted baseline values representing each day of the year. A comment section is also provided.


Component values are coded as signed integers, right-justified with a field width of 7. Total field (Delta F) values are coded as signed integers, right-justified with a field width of 5. The field widths must be maintained, either through zero-filling or space-filling. The '+' sign for positive values is optional.

Description of IBF parameters
Parameter Description
COMP Order of components HDZF, XYZF
HHHHHH Annual mean value of H component in nT.
IDC IAGA three-letter observatory ID code eg: BOU for Boulder, OTT for Ottawa, LER for Lerwick, etc.
YEAR 4-digit Year: for example, 1991.
DDD Day of the year
AAAAAAA Signed value of H or X in 0.1 nT
BBBBBBB Signed value of D or Y in 0.1 nT or 0.1 min of arc
ZZZZZZZ Signed value of Z in 0.1 nT
FFFFF Signed value of Delta F, the difference between calculated and observed value of F (by a proton magnetometer) in 0.1 nT
* Section separator
_ Indicates a space character
CrLf Indicates a Carriage return, Line feed

Missing values must be replaced by 999999 for D, H, X, Y, Z and by 9999 for F.

File name convention is IAGYR.BLV where IAG = 3-letter observatory IAGA code and YR = 2-digit year.