Enhancing Operational Safety during the Medium-Term Implementation of Performance Based Navigation (PBN) in African Equatorial/Low Latitude Ionosphere.
Abstract
The medium - term phase implementation of PBN was programmed to focus on introducing GNSS with augmentation to enable high performance approach and landing capabilities . The GNSS augmentation systems that may begin to evolve in this time frame are GBAS and SBAS. Operational safety of SBAS requires information on the ionospheric vulnerabilities that may disrupt effective services. We therefore investigated the responses of GPS-TEC measurements at eight African equatorial/low latitude stations, namely, Cape Verde (16.00oN, 24.01oW geographic coordinates, 6.62oN magnetic latitude); Asab (13.06oN, 42.65oE, 4.92oN)[Eriteria]; Dakar (14.72oN, 17.43oW, 2.34oN) [Senegal]; Addis Ababa (9.04oN, 38.77oE, 0.18oN) [Ethiopia]; Cotonou (6.38oN, 2.45oE, 3.08oS)[Republic of Benin]; Eldoret (0.28oN, 35.29oE, 9.18oS) [Kenya]; Malindi (2.99oS, 40.19oE, 12.42oS) [Kenya] and Diego Garcia (7.32oS, 72.42oE, 16.94oS)[British Indian Ocean Territory] to the intense geomagnetic storms of solar cycle 24. The responses of scintillation measurements at two of the stations to the storms were also investigated. The Rate of change of TEC Index (ROTI) was use as proxy for ionospheric irregularities in the other stations. Overall, the African equatorial/low latitude ionosphere was clearly modified by dayside geomagnetic storm occurrences and the responses of the ionosphere to the geomagnetic storms were dependent on factors such as, the location's local time when the geomagnetic storm starts unfolding, geomagnetic storm's intensity, season and solar activity. Also latitudinal difference plays significant role in the intensity and pattern of irregularities across the region.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFMSA31B..03A
- Keywords:
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- 7924 Forecasting;
- SPACE WEATHER;
- 7934 Impacts on technological systems;
- SPACE WEATHER;
- 7944 Ionospheric effects on radio waves;
- SPACE WEATHER