Abstract Slant absolute total electron content (TEC) is observed by the Formosa Satellite‐7/Constellation Observing System for Meteorology, Ionosphere, and Climate‐2 (FORMOSAT‐7/COSMIC‐2, F7/C2) Tri‐GNSS Radio Occultation System (TGRS) instrument. We present details of the data processing algorithms, validation, and error assessment for the F7/C2 global positioning system (GPS) absolute TEC observations. The data processing includes estimation and application of solar panel dependent pseudorange multipath maps, phase to pseudorange leveling, and estimation of separate L1C‐L2C and L1C‐L2P receiver differential code biases. We additionally perform a validation of the F7/C2 GPS absolute TEC observations through comparison with colocated, independent, TEC observations from the Swarm‐B satellite. Based on this comparison, we conclude that the accuracy of the F7/C2 GPS absolute TEC observations is less than 3.0 TEC units. Results are also presented that illustrate the suitability of the F7/C2 GPS absolute TEC observations for studying the climatology and variability of the topside ionosphere and plasmasphere (i.e., altitudes above the F7/C2 orbit of550 km). These results demonstrate that F7/C2 provides high quality GPS absolute TEC observations that can be used for ionosphere‐thermosphere data assimilation as well as scientific studies of the topside ionosphere and plasmasphere. 
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                            A comparison of Jason-2 plasmasphere electron content measurements with ground-based measurements
                        
                    
    
            Abstract. Previous studies utilizing the Global Positioning System(GPS) receivers aboard Jason satellites have performed measurements ofplasmasphere electron content (PEC) by determining the total electroncontent (TEC) above these satellites, which are at altitudes of about 1340 km. This study uses similar methods to determine PEC for the Jason-2receiver for 24 July 2011. These PEC values are compared to previousdeterminations of PEC from a chain of ground-based GPS receivers in Africausing the SCORPION method, with a nominal ionosphere–plasmasphere boundaryat 1000 km. The Jason-2 PECs with elevations greater than 60∘were converted to equivalent vertical PEC and compared to SCORPION verticalPEC determinations. In addition, slant (off-vertical) PECs from Jason-2were compared to a small set of nearly co-aligned ground-based slant PECs.The latter comparison avoids any conversion of Jason-2 slant PEC toequivalent vertical PEC, and it can be considered a more representativecomparison. The mean difference between the vertical PEC (ground-basedminus Jason-2 measurements) values is 0.82 ± 0.28 TEC units (1 TEC unit=1016 electrons m−2). Similarly, the mean differencebetween slant PEC values is 0.168 ± 0.924 TEC units. The Jason-2 slantPEC comparison method may provide a reliable determination for theplasmasphere baseline value for the ground-based receivers, especially ifthe ground stations are confined to only midlatitude or low-latituderegions, which can be affected by a non-negligible PEC baseline. 
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                            - Award ID(s):
- 1848730
- PAR ID:
- 10515562
- Publisher / Repository:
- European Geosciences union
- Date Published:
- Journal Name:
- Annales Geophysicae
- Volume:
- 41
- Issue:
- 1
- ISSN:
- 1432-0576
- Page Range / eLocation ID:
- 269 to 280
- Subject(s) / Keyword(s):
- plasmasphere electron content
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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