This section describes the processing that was undertaken to produce a clean observatory hourly dataset for the years 1965 - 1982 to overlap POGO and Magsat lifetimes. This dataset was created to be included in the Solar Quiet modeling effort of Terry Sabaka (HSTX), Nils Olsen (Department of Geophysics, Copenhagen University, Denmark), Bob Langel (NASA), and Joy Conrad (HSTX) in February 1996. The files referenced in this section can be found on CD: SQOBS001 in the Geomagnetics library at the Goddard Space Flight Center.
The hourly mean observatory data were obtained from the CD-ROM supplied by the National Geophysical Data Center entitled ``Solar Variability Affecting Earth 05/01" and from additional hourly data supplied by Nils Olsen. The original data is in:
/obs/hourly/obs_6582.mrg
in NGDC hourly format (NGDCHR). Only the quietest day per month was selected based on the daily sum of 3 hourly Kp values. The days selected using kpquiet.f are:
This data was converted into X Y Z components then written out in newfit binary (BINC) with /source/hourly/updatngd.x which executes:
/source/hourly/hrxyz.f
Purpose: converts data to XYZ skipping any day with more than three bad (pad=9999) hours
Input/Output: NGDC hourly format (NGDCHR)
/source/hourly/updatngd.f
Purpose:
1.Converts station abbreviation to station name
2.Changes station name to standard alternate name
3.Applies station breaks on the calendar year
4.Writes data out in newfit format
Input: NGDC hourly format (NGDCHR)
Output: newfit binary with computed array (BINC)
The computed values were then added to the file with the GSFC Cray Supercomputer based on the gsfcsqM95 Solar Quiet model as well as magnetic dipole colatitude and magnetic local time information. The output file from these programs is:
/obs/obsmrg.cor
in newfit binary (BINC) format.
The data were then edited by hand using the IDL Widget Data Analysis Tool. The programs associated with this tool are in /source/sq/widget/. Instructions for using the widget can be found in
readme.sqw
Since the station breaks were determined based on annual means, they were implemented on the half year. In many cases the change in operation occurred other times of the year. In these cases the time of the station break was moved. There were also several outliers or anomalous points in the data. The data that was deemed inappropriate for use in the modeling process was ``deleted" by changing the quality code of the respective component in the data record to ``0". The following data were deleted:
STATION ABB LAT LON YEAR MONTH COMPONENT ALERT ALE 82.497 297.647 65 S,O Z deleted 79 N XYZ deleted ALIBAG ABG 18.638 72.872 66 May Z deleted ALMA ATA AAA 43.250 76.917 65 all D shifted 1/2 deg 80 O Y 1 hr deleted 80 N Z deleted APIA API -13.807 188.225 65 all H shifted 100 nT AQUILA AQU 42.383 13.317 70 S Z deleted BAKER LAKE BLC 64.333 263.967 71 Jan Z deleted BYRD BYR -80.017 240.483 65 D XYZ deleted 67 July XY deleted 67 D Z deleted CANARIAS SZT 28.477 343.739 65,66 all station deleted CAPE WELLEN CWE 66.163 190.165 66 Apr XZ deleted 67 June Z deleted 69 all Z shifted 100 nT 70 Apr,May X deleted CHANGCHUN CNH 43.827 125.299 79 all Y deleted DIXON ISLAND DIK 73.543 80.562 67 Jan,F Z deleted 81 F XY deleted DUMONT DURVIL DRV -66.665 140.007 68 F,O XY deleted 68 all Z shifted 100 nT DUSHETI TFS 42.092 44.705 70 Apr,S Y deleted EBRO EBR 40.820 .493 65 N X deleted FORT CHURCHILFCC 58.759 265.912 67 Jan Z deleted 67 May X deleted FURSTENFELDBR FUR 48.165 11.277 82 O XYZ 1 hr deleted GODHAVN GDH 69.240 306.478 66 S 3 hours deleted 68 June,July hours deleted GORNOTAYEZHNA VLA 43.683 132.167 65 S,O,N Z deleted 66 O Z deleted 67 Mar Z deleted 69 July,Aug X deleted 71 all D shifted 1/4 deg 80 June Z deleted 81 Jan XY deleted 82 Mar Y deleted GREAT WHALE GWC 55.267 282.217 66 N Z deleted 66 D X deleted HAVANA HVN 23.068 277.540 67 S,O Y sign changed IRKUTSK IRT 52.267 104.267 82 N Z deleted KIEV KIV 50.717 30.300 80 May Z deleted KIRUNA KIR 67.833 20.417 65 all Y shifted 1000 nT KIRUNA II KIR 67.833 20.417 67 all XYZ deleted KODAIKANAL KOD 10.230 77.463 80 Jan Z deleted LA QUIACA LQA -22.103 294.395 66 Mar XYZ deleted LEIRVOGUR LRV 64.183 338.300 71 Jan,F,June hours deleted Z shifted 1000 nT NARSSARSSUAQ NAQ 61.100 314.800 71 Apr XY deleted NURMIJARVI NUR 60.508 24.655 68 D XYZ 1 hr deleted PAMATAI PPT -17.568 210.425 80 all D shifted 260/600 deg PARAMARIBO PAB 5.810 304.778 67 all H shifted 100 nT ROBURENT ROB 44.297 7.888 65 O X deleted SABHAWALA SAB 30.363 77.798 65 all D shifted 1/6 deg SAN JUAN SJG 18.113 293.850 65 all XYZ deleted SANAE I SNA -70.300 357.633 68 Mar Z 1 hr deleted SANAE II SNA -70.320 357.663 71 June,July Y deleted SHESHAN SSH 31.097 121.187 65 all D shifted 2 deg 80,81 all D sign changed SOUTH POLE SPA -89.993 346.678 69 May-S Z deleted 70 July,Aug XY deleted STEKOLINIY MGD 60.117 151.017 80 all D shifted STEPANOVKA ODE 46.783 30.883 82 May,S X deleted SURLARI SUA 44.680 26.253 65 D Z deleted TANANARIVE TAN -18.917 47.550 67 Aug XZ deleted 70 Jan XYZ deleted TANGERANG TNG -6.167 106.633 66 O Z deleted 67 O XZ deleted 69 all XYZ deleted TIKSI TIK 71.583 129.000 69 all Z deleted TOOLANGI TOO -37.533 145.467 65 all H shifted 200 nT TROMSO TRO 69.663 18.948 68 all XYZ deleted UJJAIN UJJ 23.183 75.783 82 July X deleted VASSOURAS VSS -22.400 316.350 79,80 all Z shifted 50 nT VIEQUES VQS 18.147 294.552 65 all XYZ deleted VOSTOK VOS -78.450 106.867 71 all Z additive sign changed 80 all D shifted 1/2 deg VYSOKAYA DUBR SVD 56.733 61.067 80 all break added to hourly and annual means WILKES WIL -66.250 110.583 65 D Y deleted YANGI-BAZAR TKT 41.333 69.300 66,68,69,70 D shifted 1/2 deg 71 all Z additive sign changed YELLOWKNIFE YKC 62.482 245.518 82 Apr Z deleted YUZHNO SAKHAL YSS 46.950 142.717 81,82 all Y sign sign 81 F Y deleted
Duplicate Stations:
CANARIAS SZT was chosen over TEN
PORT-AUX-FRANCAIS PAF was chosen over KGL
CANBERRA CAN was chosen over CNB
The final cleaned dataset with 209108 records is:
/obs/obsmrg.cor
Further analysis uncovered a time error of 1800000 msec. This error was corrected, then the file was reformatted to be used in the Sq modeling process (see Section 3.6). Values that differed from computed model values by more than 150 nT were then `deleted' from the data by changing the quality codes to `3'. Refer to Table 3.2 for the number of points in the original and final datasets. The final file is named obshr.iee on SQOBS002.