Reprocessing of TEMPO Gridded Ozone Total Column Level 3 Version 04 (TEMPO_O3TOT_L3_V04) Announcement
Posted: Fri Apr 03, 2026 2:14 pm America/New_York
The TEMPO O3TOT L3 V04 data reprocessing is completed. All of the data available in Earthdata Search is now the updated version.
Please do not hesitate to reach out with any questions or concerns.
Regards,
Atmospheric Science Data Center (ASDC) User Services team
asdc-support@earthdata.nasa.gov
The TEMPO O3TOT L3 V04 data currently has a grid of 0.04 degrees (latitude) x 0.02 degrees (longitude). However, the TEMPO Science Team is updating the processing algorithm to 0.02 degrees (latitude) x 0.02 degrees (longitude). The TEMPO Science Team is making this change to keep the TEMPO O3TOT L3 resolution consistent with the previous version of TEMPO O3TOT L3 data files and to make it consistent with other TEMPO Level 3 products, including nitrogen dioxide (NO2), formaldehyde (HCHO), and clouds (CLDO4). Switching the TEMPO O3TOT L3 V04 data to the 0.02 degrees (latitude) x 0.02 degrees (longitude) grid may result in different values compared to those in the existing 0.04 degrees (latitude) x 0.02 degrees (longitude) files due to how the different pixel size will be impacted by the interpolation method. This may lead to small changes in individual grid values, spatial patterns, coverage, and aggregated statistics. Array dimensions will also change, so user applications that assume the current grid structure may need to be updated.
TEMPO O3TOT Level 2 V04 data files will NOT be affected in this reprocessing.
The TEMPO Science Team will be replacing TEMPO O3TOT L3 V04 products for the following date ranges:
1) August 2, 2023 – September 7, 2023
2) July 15, 2024 – August 15, 2024
3) September 17, 2025 – April 1, 2026
The forward processing of the TEMPO O3TOT L3 V04 data will begin April 2, 2026. The existing TEMPO O3TOT L3 V04 data will be overwritten. This reprocessing will also begin on April 2, 2026, and is expected to take about a week.
If you have previously downloaded TEMPO O3TOT L3, the TEMPO Science Team recommends to redownload the new data to replace the previous download.
Please note that the reprocessed data will have the SAME filename as the previous data on the coarser grid that are being overwritten; therefore, you will not be able to determine which files are the new files by looking at the filename. Reprocessed files can be identified by the production date time and Science Data Processing Center (SDPC) version variables in the metadata.
Identifying files in Earthdata Search:
In Earthdata Search, users can view the metadata by opening the TEMPO_O3TOT_L3_V04 collection. Each granule has a three-dot menu on the top right. Click on the three-dot menu, and click “View details” to display the metadata. View the "productionDateTime" variable to view the production date.
"productionDateTime"—the revised data will have an April 2026 date (the old data will have dates between September 2025 and April 1, 2026)
Identifying files by looking at the file itself:
Open the file in a file viewer, such as Panoply. In the global attributes, view the production_date_time and sdpc_version variables
The TEMPO O3TOT user guide has been updated to reflect this change and can be found on the TEMPO O3TOT L3 V04 collection page.
Please do not hesitate to reach out with any questions or concerns.
Regards,
Atmospheric Science Data Center (ASDC) User Services team
asdc-support@earthdata.nasa.gov
The TEMPO O3TOT L3 V04 data currently has a grid of 0.04 degrees (latitude) x 0.02 degrees (longitude). However, the TEMPO Science Team is updating the processing algorithm to 0.02 degrees (latitude) x 0.02 degrees (longitude). The TEMPO Science Team is making this change to keep the TEMPO O3TOT L3 resolution consistent with the previous version of TEMPO O3TOT L3 data files and to make it consistent with other TEMPO Level 3 products, including nitrogen dioxide (NO2), formaldehyde (HCHO), and clouds (CLDO4). Switching the TEMPO O3TOT L3 V04 data to the 0.02 degrees (latitude) x 0.02 degrees (longitude) grid may result in different values compared to those in the existing 0.04 degrees (latitude) x 0.02 degrees (longitude) files due to how the different pixel size will be impacted by the interpolation method. This may lead to small changes in individual grid values, spatial patterns, coverage, and aggregated statistics. Array dimensions will also change, so user applications that assume the current grid structure may need to be updated.
TEMPO O3TOT Level 2 V04 data files will NOT be affected in this reprocessing.
The TEMPO Science Team will be replacing TEMPO O3TOT L3 V04 products for the following date ranges:
1) August 2, 2023 – September 7, 2023
2) July 15, 2024 – August 15, 2024
3) September 17, 2025 – April 1, 2026
The forward processing of the TEMPO O3TOT L3 V04 data will begin April 2, 2026. The existing TEMPO O3TOT L3 V04 data will be overwritten. This reprocessing will also begin on April 2, 2026, and is expected to take about a week.
If you have previously downloaded TEMPO O3TOT L3, the TEMPO Science Team recommends to redownload the new data to replace the previous download.
Please note that the reprocessed data will have the SAME filename as the previous data on the coarser grid that are being overwritten; therefore, you will not be able to determine which files are the new files by looking at the filename. Reprocessed files can be identified by the production date time and Science Data Processing Center (SDPC) version variables in the metadata.
Identifying files in Earthdata Search:
In Earthdata Search, users can view the metadata by opening the TEMPO_O3TOT_L3_V04 collection. Each granule has a three-dot menu on the top right. Click on the three-dot menu, and click “View details” to display the metadata. View the "productionDateTime" variable to view the production date.
"productionDateTime"—the revised data will have an April 2026 date (the old data will have dates between September 2025 and April 1, 2026)
Open the file in a file viewer, such as Panoply. In the global attributes, view the production_date_time and sdpc_version variables
- "productionDateTime" production_date_time—this will be an April 2026 date (the old data will have dates between September 2025 and April 1, 2026)
- sdpc_version will be "TEMPO_SDPC_v4.8.3" (the old data state TEMPO_SDPC_v4.6.1)
The TEMPO O3TOT user guide has been updated to reflect this change and can be found on the TEMPO O3TOT L3 V04 collection page.