Seasonal variation of Global NmF2 distribution by FORMOSAT-7/COSMIC-2 Radio Occultation
Abstract
The FORMOSAT-7/COSMIC-2 (F7/C2) mission is a satellite constellation for the research of meteorology, ionosphere, climatology, and space weather. This mission is operated by the National Space Organization (NSPO) on the Taiwanese side and National Oceanic and Atmospheric Administration (NOAA) as well as the United States Air Force (USAF) on the United States side. The six F7/C2 satellites were launched on June 25th in 2019, operating in the circular Low Earth Orbit (LEO) with an altitude of ~520 - 550 km. As a follow-on mission of FORMOSAT-3/COSMIC to meet the Radio Occultation (RO) data continuity requirements for global users, F7/C2 offers thousands of RO electron density (Ne) profiles daily between the southern and northern latitude 40$^\circ$. The space-time sampling of F7/C2 data is quantified as 30-day averaging window and binned into overlapping longitude bins spaced per 45$^\circ$ by 4 hours. The result of space-time sampling analysis indicates that data is fully covering 4-hour grid within latitude 40$^\circ$, and is capable of resolving zonal wave numbers up to 4. To study tidal and stationary planetary wave (SPW) signatures, the phase and amplitude were calculated with least squares method in this study. The median values of the global F2-layer peak density (NmF2), the median height of the F2-layer peak density (hmF2) and the zonal mean of the Ne profiles of different longitude sections on September 2019, December 2019, March 2020 and June 2020, are analyzed to compare the seasonal variations. For the analysis of zonal mean profiles, there are 12 longitudinal sections with every 30$^\circ$, and features are shown in different areas varying though 16 - 02 local time in March, June, September and December. An ascend of the global upper atmosphere studies is foreseen, relying on the F7/C2 data.
- Publication:
-
43rd COSPAR Scientific Assembly. Held 28 January - 4 February
- Pub Date:
- January 2021
- Bibcode:
- 2021cosp...43E.625D