JAXA Supercomputer System Annual Report February 2024-January 2025

Report Number: R24ER2100

Subject Category: Space Technology

PDF (to be added)

• Responsible Representative: Hiroshi Suto ,Space Technology Directorate I Satellite Applications and Operations Center, Mission Manager
• Contact Information: Kei Shiomi, Rio KAJIURA, Shin ISHIDA
  (shiomi.kei@jaxa.jp;kajiura.rio@jaxa.jp;ishida.shin@jaxa.jp)
• Members: Masahito Arai, Takashi Goto, Makiko Hashimoto, Hidetoshi Hayasaka, Shin Ishida, Makoto Imanaka, Kenji Kowata, Rio Kajiura, Fumie Kataoka, Mizuki Kato, Nobuhiro Kikuchi, Kazuhiro Matsumoto, Tomoyuki Mabuchi, Itaru Nishido, Hiroshi Suto, Hideki Suetake, Yoko Ueda, Kai Uematsu, Shu Yano

Abstract

GOSAT continues its observations for 16-years beyond its 5-year mission, providing well-calibrated high spectral resolution data. The overall functions and performances are successful and no significant degradation of SNR and spectral resolution has been observed. Several anomalies were found onboard, but they have stabilized since. The Level 1 algorithms have been updated since launch in order to correct these anomalies.

Reference URL

Please refer to ‘HOME – GOSAT – JAXA‘.

Reasons and benefits of using JAXA Supercomputer System

GOSAT mission utilizes JSS3 as one of the GOSAT Mission Operation System which processes the observation data of GOSAT. When processing algorithm is updated, JSS3 reprocesses all data observed in the past. When we calibrate products, JSS3 processes all data in the past. Also, JSS3 is used as a remote storage of all data required for its reprocessing.

Achievements of the Year

(1)Calibration and validation of GOSAT TANSO-CAI data

On-orbit sensor sensitivity change is evaluated from TANSO-CAI observation data. We expect to determine the CAI Band 1 radiometric calibration factor (or formula) by calculation of radiative transfer model using in-situ and other satellite data. The CAI Band 1 has an important information of aerosol size distribution. Hence, Band 1 radiance is optimized to agree with calibrated radiances of Band 2 and Band 3. Calibration formula of Band 2 and Band 3 are obtained as three candidates. Thus, Band 1 calibration factor is determined by calculations in these three cases. Figure 1 shows a schematic flow of the CAI radiometric calibration method. Figure 2 shows the radiometric calibration factors.

Data period: February 2024 – October 2024 (every 4 months)

(2) Accuracy verification of the GOSAT Level 1 processing after OS version upgrade

After upgrading the OS of the mission operation system, accuracy verification was conducted to ensure that the Level1 1 processing was operated without issues and that anomalous products were not generated. It was confirmed that there were no significant differences.

Fig.1: GOSAT CAI processing flow (top) and radiometric calibration flow (bottom)

Fig.2: CAI radiometric calibration factor by inter-satellite cross calibration method

Publications

– Web

https://www.eorc.jaxa.jp/GOSAT/currentStatus_11.html

https://data2.gosat.nies.go.jp/gallery/CAIL3oneday_en.html

Usage of JSS

Computational Information

• Process Parallelization Methods: N/A
• Thread Parallelization Methods: N/A
• Number of Processes: 1
• Elapsed Time per Case: 30 Minute(s)

JSS3 Resources Used

Fraction of Usage in Total Resources*1(%): 0.06

Details

Please refer to System Configuration of JSS3 for the system configuration and major specifications of JSS3.

*1: Fraction of Usage in Total Resources: Weighted average of three resource types (Computing, File System, and Archiver).

*2: Fraction of Usage：Percentage of usage relative to each resource used in one year.

ISV Software Licenses Used

*2: Fraction of Usage：Percentage of usage relative to each resource used in one year.

JAXA Supercomputer System Annual Report February 2024-January 2025