Format Documentation of kpyymm.tab Files

Availability

The most recent kpyymm.tab (yymm stands for year and month, each expressed with two digits) files are distributed per e-mail half-monthly by

Dr. H.-J. Linthe, mailto:kp_index@gfz-potsdam.de

Both recent and past tables are supplied as an archive on the FTP servers

Denmark: ftp://ftp.dmi.min.dk/pub/Data/WDCC1/indices/kp-ap/

Germany: ftp://ftp.gfz-potsdam.de/pub/home/obs/kp-ap/

WWW access: http://www.gfz-potsdam.de/~kp_index/

Note: FTP sites sometimes refuse connections due to excessive traffic.
Your mileage may vary with a different FTP program or the WWW access alternative.

Background information on geomagnetic indices and the classification of days is supplied at the WWW startpage http://www.gfz-potsdam.de/~kp_index/

Format Description

This format is intended to be easily readable for both humans and computer programs and have some resemblance to the regular mail distribution.

Since many observatories are interested mainly in the international quietest and most disturbed days, beginning August 1996 three extra lines have been added to the end of the table containing these values in an easy to read form. The extra lines are included in the complete monthly tables only.

half-monthly distribution: days 1 through 15 and days 1 through 28 / 29 / 30 / 31
monthly distribution: days 1 through 28 / 29 / 30 / 31

The geomagnetic indices in the kpyymm.tab files are supplied in the following format.

The table begins with the daily lines

Column  Format  Description
======  ======  ===========
 1- 2     i2    yy, last two digits of year
 3- 4     i2    mm, month (1-12)
 5- 6     i2    dd, day of month (1-31)
 8-19    4a3    3-hourly Kp indices, first 4 values
21-32    4a3    3-hourly Kp indices,  last 4 values
35-38     a4    Daily Kp sum (supplied only for tradition,
                              use Ap scientific purposes!)
39-42     a4    Most disturbed and quiet days;
                Q: most quiet days (1-10, 10th quiet day is marked Q0)
                D: most disturbed days (1-5)
                A, K: not really quiet day
                *: not really disturbed day
43-45     i3    Ap index
46-50     f5.2  Cp geomagnetic index.

Either one line or four lines follow the daily lines

1. This line contains the monthly mean values for Ap and Cp

 1- 2     i2    yy, last two digits of year
 3- 4     i2    mm, month (1-12)
 5- 6     i2    day is blank, may be read as zero
39-42     a4    "Mean", denotes monthly mean average of Ap and Cp
43-45     i3    Ap index (monthly mean)
46-50     f5.2  Cp geomagnetic index (monthly mean).

Lines 2-4 in monthly distribution only

2. Empty line
3. This line contains the ordered most quiet days

 1- 2     i2    yy, last two digits of year
 3- 4     i2    mm, month (1-12)
 5- 6     a2    " Q"
 7-46   10a4    most quiet days 1 to 10 (day of month)
                A, K: not really quiet day

4. This line contains the ordered most disturbed days

 1- 2     i2    yy, last two digits of year
 3- 4     i2    mm, month (1-12)
 5- 6     a2    " D"
 7-26    5a4    most disturbed days 1 to 5 (day of month)
                *: not really disturbed day

For questions concerning specific data or the contents of this page, please contact: