Table 1: Data Sources for IGRA
| |
Data Source |
Period of Record |
Area of Coverage |
Number of Stations |
Percent of IGRA Soundings |
| Core |
NCDC Historical GTS |
1963-1970 |
Global |
820 |
7.94 |
| NCAR/NCEP GTS |
1970-1972 |
Global |
848 |
3.01 |
| NCEP GTS |
1973-1999 |
Global |
1517 |
64.06 |
| NCDC Real-Time GTS |
2000-present |
Global |
1093 |
7.13 |
| Other Large Scale |
Russian GTS |
1998-2001 |
Global |
923 |
1.59 |
| U.S. Air Force |
1946-1973 |
Global |
292 |
4.49 |
| Australian GTS |
1990-1993 |
Southern Hemisphere |
170 |
0.15 |
| Country-specific |
U.S. |
1946-2001 |
U.S. & U.S. military |
150 |
9.81 |
| Australian |
1938-1989 |
Australia & territories |
17 |
1.63 |
| Argentine |
1958-1991 |
Argentina |
8 |
0.18 |
| South Korean |
1984-1992 |
South Korea |
4 |
0.01 |