Sodankylä
Geophysical
Observatory
Oulun yliopisto

Magnetometer Data Formats

   
Sodankylä 1 min data, daily tables
Column Format Description
1 - 8 F8.1 X component in nT
9 - 16 F8.1 Y component in nT
17 - 24 F8.1 Z component in nT
26 - 27 i2 year two last digits
28 - 29 i2 month (1-12)
30 - 31 i2 day (1-31)
33 - 38 3i2 time in UT (hours, minutes, seconds)
40 i1 instrument (2 = Polish magnetometer, 4 = Danish magnetometer)

   
Hourly mean values (old WDC-format)
Data is always final data and about one year late.
Column Format Description
1 - 3 c3 Observatory code (=SOD)
4 - 5 i2 year two last digits
6 - 7 i2 month (1-12)
8 c1 component (X,Y,Z)
9 - 10 i2 day (1-31)
11 - 15 5x empty (spaces)
16 c1 character of the day (Q=quiet, D=disturbed)
17 - 20 i4 base value (hourly mean value = base value*100)
21 - 116 24i4 hourly mean values (=base value*100 + value)
117 - 120 i4 the average value of the day (=base value*100 + value)

   
Daily and monthly mean values, monthly tables
The header lines contain co-ordinates, components, month, year, and the base value. The most recent data is preliminary and that is also mentioned in the header. Data is final when there is no word 'preliminary' in the header.
Column Format Description
1 - 2 i2 day
5 i1 character of the day, Q is one of the 5 quiest days in the respective month, in the preliminary data we have used the SGO own data, In the final data we used the international character of the days
6 - 125 24i5 24 hourly values + base value in nT (e.g. X copm. base value can be e.g. 11 000 nT)
128- 132 i5 the avearage value of the day
The last 3 lines, the same as above, but for all, quiet and disturbed days.

   
K(HDZ) index, monthly tables:
Column Format Description
2 - 5 i4 year (yyyy)
6 - 7 i2 month (1-12)
8 - 9 i2 day (1-31)
12 - 15 i4 3-hourly K index (4 first), obtained from Z component (=Kz)
17 - 20 i4 3-hourly K index (4 last), obtained from Z component (=Kz)
22 - 25 i4 3-hourly K index (4 first), obtained from H component (=Kh)
27 - 30 i4 3-hourly K index (4 last), obtained from H component (=Kh)
32 - 35 i4 3-hourly K index (4 first), obtained from D component (=Kd)
37 - 40 i4 3-hourly K index (4 first), obtained from D component (=Kd)
42 - 57 8i2 3-hourly K index, obtained from H and D components (=K(hd))
60 - 61 i2 Daily sum of K(hd) indices , obtained from H and D components
63 - 65 i3 Ak index (linearized average of the K(hd) indices
67 - 82 8i2 3-hourly K index, obtained from Z, H and D components (=K(zhd))
85 - 86 i2 Daily sum of K(zhd) indices , obtained from Z, H and D components
88 - 90 i3 Ak index (linearized average of the K(zhd) indices, see below

The K value scale limits follows the definition by IAGA. The lower limit for the K-value 9 is 1500nT. The limits for the K values 0 to 9 are 15, 30, 60, 120, 210, 360, 600, 990 and 1500 nT.

Ak value is linearized average of daily K values. K values 0 to 9 are first converted ak values 0, 3, 7, 15, 27, 48, 80, 140, 240, 400, respectivility and daily mean of ak is presented as daily Ak value. With small K values average of K correlates well with Ak. Single big K value (7-9) influence to Ak, when the K average does not react to it.


   
K(HD) index:
Column Format Description
2 - 5 i4 year (yyyy)
6 - 7 i2 month (1-12)
8 - 9 i2 day (1-31)
11 - 18 8i1 3-hourly K indices, obtained from H and D components (=K(hd))
22 - 23 i2 Daily sum of K(hd) indices , obtained from H and D components
26 - 29 i3 Ak index (linearized average of the K(hd) indices, see above)

   
Q index, monthly tables:
Column Format Description
3 - 6 i4 year, (yyyy)
7 - 8 i2 month (1-12)
9 - 10 i2 day (1-31)
13 - 42 6(i4, 1x) Q index (first 6 hours, one digit for every 15 min, scale = 0 - 11, T=10, E=11)
44 - 73 6(i4,1x) Q index (next 6 hours)
75 - 104 6(i4,1x) Q index (next 6 hours)
106 - 134 5(i4,1x),i4 Q index the last 6 hours)

Last modified: 28 August 2015, 11:29:07.