GNSS-derived TEC observations at low-latitude African stations (ABIP, ACCP, ADOE) during March and April 2025 geomagnetic storms

This dataset contains GNSS-derived vertical total electron content (VTEC) observations at three low-latitude African stations during two geomagnetic storm intervals in 2025, including both storm-period and quiet-day reference data used to compute the percentage TEC deviation (dTEC%). ================================================================STATIONS:================================================================- ABIP: Abidjan, Côte d'Ivoire (Geo. Lat: 5.33°N, Geo. Lon: 4.02°W,        Geomag. Lat: -7.77°, Geomag. Lon: 70.41°)- ACCP: Accra, Ghana (Geo. Lat: 5.56°N, Geo. Lon: 0.20°W,        Geomag. Lat: -7.38°, Geomag. Lon: 74.45°)- ADOE: Ado-Ekiti, Nigeria (Geo. Lat: 7.61°N, Geo. Lon: 5.23°E,        Geomag. Lat: -4.78°, Geomag. Lon: 80.11°) ================================================================STORM PERIODS COVERED:================================================================- March storm: 19–25 March 2025- April storm: 13–18 April 2025 ================================================================QUIET DAY REFERENCE DATA:================================================================Quiet days were selected from the official quiet day list provided by the World Data Centre for Geomagnetism, Kyoto:wdc.kugi.kyoto-u.ac.jp March 2025 quiet days used: 3, 30, 31 March 2025(March 2 and 20 were excluded because the preceding days were geomagnetically disturbed, with AE index reaching ~1000 nT) April 2025 quiet days used: 1, 25, 26, 28, 29 April 2025 The quiet-day mean TEC (TECq) was computed as the average of these quiet days at each station and used as the baseline for computing dTEC(%) following Trivedi et al. (2011): dTEC(%) = (TECs - TECq) / TECq × 100 where TECs is the storm-time TEC and TECq is the quiet-day mean. ================================================================DATA PROCESSING:================================================================- Software: GPS-TEC analysis software Version 3.5 (Seemala, 2023)- Satellite elevation cutoff angle: 30°- Temporal resolution: 1-minute cadence, averaged to 5 minutes- DCB corrections: Centre for Orbit Determination in Europe   (CODE), available at ftp://ftp.aiub.unibe.ch/CODE/- GNSS data for ABIP and ACCP: Abdus Salam International Centre   for Theoretical Physics (ICTP), Trieste, Italy- GNSS data for ADOE: Space Research Laboratory, Afe Babalola   University, Ado-Ekiti, Nigeria (GNSS receiver provided by ICTP) ================================================================FILE STRUCTURE:================================================================Storm period files (6 files):- ABIP_TEC_March2025.csv- ACCP_TEC_March2025.csv- ADOE_TEC_March2025.csv- ABIP_TEC_April2025.csv- ACCP_TEC_April2025.csv- ADOE_TEC_April2025.csv Quiet day reference files (6 files):- ABIP_TEC_quietdays_March2025.csv- ACCP_TEC_quietdays_March2025.csv- ADOE_TEC_quietdays_March2025.csv- ABIP_TEC_quietdays_April2025.csv- ACCP_TEC_quietdays_April2025.csv- ADOE_TEC_quietdays_April2025.csv ================================================================FILE FORMAT:================================================================All files are CSV format with two columns:- Column 1: VTEC in total electron content units (TECU)- Column 2: Time in UTC (MM/DD/YYYY HH:MM) ================================================================REFERENCES:================================================================Seemala, G. K. (2023). Estimation of ionospheric TEC from GNSS observations. In Earth Observation, Atmospheric Remote Sensing, pp. 63–84, Elsevier. doi.org Trivedi, R., Jain, A., Jain, S., and Gwal, A. K. (2011). Study of TEC changes during geomagnetic storms near the EIA crest in the Indian sector. Advances in Space Research, 48(10), 1617–1630. WDC for Geomagnetism, Kyoto (2025). Geomagnetically quiet day list. World Data Centre for Geomagnetism, Kyoto. wdc.kugi.kyoto-u.ac.jp