A Comparison of Sporadic-E Occurrence Rates Using GPS Radio Occultation and Ionosonde Measurements
Abstract
Sporadic-E (Es) occurrence rates from Global Position Satellite radio occultation (GPS-RO) measurements have shown to vary by a factor of five between studies, motivating the need for a comparison with ground-based measurements. In an attempt to find accurate GPS-RO techniques for detecting Es formation, occurrence rates derived using five previously developed GPS-RO techniques are compared to ionosonde measurements over an eight-year period from 2010–2017. GPS-RO measurements within 170 km of a ionosonde site are used to calculate Es occurrence rates and compared to the ground-truth ionosonde measurements. The techniques are compared individually for each ionosonde site and then combined to determine the most accurate GPS-RO technique for two thresholds on sporadic-E intensity: no lower limit and fbEs ≥3 MHz. Overall, the YuS4 method shows the closest agreement with ionosonde measurements for total Es occurrence rates without a lower limit on intensity, while the phase-based Chu technique shows the closest agreement for fbEs ≥3 MHz. This analysis demonstrates that the variation in GPS-RO derived sporadic-E occurrence rates is due to varying thresholds on the sporadic-E intensities in terms of fbEs.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jan 26, 2022
- Source ID
- 10.3390/rs14030581
Entities
People
- Daniel J. Emmons
- E. V. Dao
- Omar A. Nava
- Rodney A. Carmona
Organizations
- Air Force Office of Scientific Research