1. Global Navigation Satellite System (GNSS) Ionosphere Vertical Total Electron Content (VTEC) Analysis Center Product from NASA CDDIS
  2. temporal
YearFile Count
19981791
19991681
20001072
20011030
2002946
20031008
20041039
20051510
20061454
20071612
20081675
20091569
20101656
20111616
20123904
20131866
20143361
20154604
20166880
20176592
20186326
20191940
20201222
20211201
2022811
20231869
20241814