Landsat Reprocessing Events

Large-scale Reprocessing Events  

Large-scale reprocessing events are rare and may affect a single or entire Landsat dataset, or they may affect multiple Landsat datasets – and all the products contained in them. Previous large-scale reprocessing events include the first-year reprocessing of the entire Landsat 9 Level-1 inventory to apply calibration updates. Details about large scale reprocessing events are posted on the Landsat Collection 2 Reprocessing Events webpage. 

When Landsat data are reprocessed during large-scale events, the already existing products affected (Level-1, U.S. Analysis Ready Data (ARD) and Level-2, /Level-3) are removed and regenerated using the newly processed data. 

How to know if products over your study area have been reprocessed 

When Landsat Level-1 products are reprocessed, the latest calibration parameters are applied to the data. While this may not drastically change the data, scientific comparisons may indicate differences when comparing the original to the newly generated product. 

Landsat Level-1 Product Identifiers clearly display the processing date (i.e., LE07_L1GT_135040_20000418_20240612_02_T2). In this example, a new Collection 2 Level-1 product was generated when data was received from an IGS in support of the LGAC effort in 2024. The newly generated Level-1 product replaced the product that was originally-processed into Collection 2 in 2020.   

How to locate reprocessed Landsat products  

There are several ways to locate Landsat products that have been reprocessed. Visit the links below to access the USGS inventory.  

1. Conduct a search using EarthExplorer: Enter a date range of the processing date on the Additional Criteria tab.  

2. The Landsat Bulk Metadata Service contains files of Landsat Level-1, Level-2 and U.S. ARD products. These files are updated daily. 

3. The USGS EROS Machine-to-Machine (M2M) Application Programming Interface (API) is an alternative method of searching and acquiring data from the USGS/EROS data inventories. 

Announcements will be made on the Landsat Missions Web Site  and USGS Landsat social media accounts when large-scale or occasional reprocessing events are required to ensure all users are aware of the affected products and timeframe of the reprocessing.  

Please contact USGS EROS Customer Services with any questions about Landsat reprocessing events.