1 / 23

Reprocessed constant calibration L1c OTT drift study

This study investigates the long-term drift observed in reprocessed constant calibration data (L1c.OTT) from the South Pacific region, covering trajectories from January to December 2010. Analysis of ascending and descending half-orbits (58 each) reveals significant temperature drifts of -0.5K and +0.5K in horizontal and vertical polarizations, respectively. Additionally, the impact of galactic model errors and unexplained biases is discussed, highlighting potential causes such as cross-polarization noise and sun aliases. Recommendations for refining operational procedures and addressing data irregularities are provided.

jacob-byers
Download Presentation

Reprocessed constant calibration L1c OTT drift study

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Reprocessed constant calibration L1c OTT drift study 13 April 2011 ARGANS & L2OS ESL ascending descending

  2. Reprocessed constant calibration L1c OTT L1c reprocessed constant calibration data: pre-select South Pacific half-orbits: > 2000 grid points in region latitude -30 to 0, longitude -130 to -120 select one half orbit at 6 day intervals: January - December 2010 sub-set ascending (58) & descending (58) orbits OTT1 made using L2OS v500 candidate & compareTBs v1.3, latitude -50 to +10 snaps filtered for: far from land, sun/galactic glint, tec gradient > 20 +0.5 K drift = -1 psu

  3. Drift: -0.5 K pa in HH & VV, ascending orbits L2OS galactic model error: -1K in HH

  4. Drift: +0.5 K pa in HH & VV, descending orbits L2OS galactic model error: +1K in HH & VV

  5. Drift -0.5 K pa in HH & VV, same as AFFOV But HH bias now higher then VV (opposite to AFFOV), & unexplained low VV January – end March

  6. Drift +0.5 K pa in HH & VV, same as AFFOV But HH bias now higher then VV (opposite to AFFOV), & unexplained low HH & VV January – end March

  7. OTT anomaly 20101104T020829 reversed HH & VV bias – why?

  8. Cross-pol OTT drifts different from HH & VV in AF & EAF ascending descending

  9. ascending descending Descending OTTs show sun alias moving along AFFOV/EAFFOV hexagon

  10. orbit 20101110T013458_20101110T022859 OTT2 from L1B OTT1 from L1C OTTs from L1B (Joe) & L1C (ARGANS) visual match XX/HH YY/VV

  11. Conclusions • reprocessed constant calibration data allows identification of long-term drift • ESL recommendation for 2011 reprocessing • long-term drift: • -0.5 K pa in HH & VV, ascending orbits • +0.5 K pa in HH & VV, descending orbits • cross-pol noise/errors? • sun aliases in EAFOV? • L2OS work • correct galactic model error ±1 K • why short-term OTT irregularities? • refine OTT generation procedures

  12. Extra slides follow, showing • short integration time OTTs close to long • median OTTs different from mean • impact on OTT quality from too few snapshots

  13. AFFOV OTTs from FP short integration time close to long

  14. AFFOV OTTs from FP short integration time close to long

  15. EAFFOV OTTs from FP short integration time close to long

  16. EAFFOV OTTs from FP short integration time close to long

  17. median AFFOV OTTs different from mean

  18. median AFFOV OTTs different from mean

  19. median EAFFOV OTTs different from mean

  20. median EAFFOV OTTs different from mean

  21. tec gradient filter > 5 tec gradient filter > 20 TEC filter reduces number of snapshots: 21 snapshots (left), 210 (right)

More Related