Data

The access and use of Swarm products are regulated by ESA's Data Policy and subject to the acceptance of the specific Terms and Conditions.

In accordance with ESA Earth Observation Data Policy, all Swarm Level 1b and Level 2 products are freely accessible to all users via anonymous access.

They can be downloaded :

• via any HTTP browser at http://swarm-diss.eo.esa.int
• directly via an ftp client at ftp://swarm-diss.eo.esa.int

The top-level structure is divided into the 'Level1b', 'Level2daily', and 'L2longterm' and 'Advanced' directories. Within the 'Level1b' and 'Level2daily' directories, the structure presents first the 'Latest baselines' and 'Entire_mission_data' folders, then a Simplified datatype list, and finally, the satellite ID, if applicable.

Please also notice that for each L1/L2 directory there will be a .txt file with the list of products available at that time in the corresponding directory tree.

You can find all of the details in the document 'Swarm PDGS Data Access User Manual', and it is key to note that:

LATEST BASELINES FOLDER: the user will find all the interoperable products generated in a consistent way with the application of all significant data quality improvements, but not necessarily covering the entire mission.

ENTIRE MISSION DATA FOLDER: the users will find the full data coverage of the entire mission, regardless of any consideration of interoperability among the same product type. In other words, the data might have been produced with strategies or knowledge that does not make the products necessarily interoperable for certain types of science. This information can still be captured by looking at the Product Baseline number.

N.B. This strategy ensures that users do not mix old data with new products that have been improved in quality by significant upgrades. It might occur that not all of the old data is immediately regenerated or reprocessed into the 'Latest_baselines' Folder. Therefore if the user does not find the improved product in the 'Latest_baselines' Folder but s/he is nonetheless interested in accessing the data without the significant data quality improvements, s/he can find them in the 'Entire_mission_data' Folder.

PRODUCT BASELINE: is a number associated with a specific product type and satellite. The Product Baseline is identified by the first two of the four digits placed at the end of the file name, i.e. the first two digits of the File_Version field represent the Product Baseline, while the last two represent an incremental File Counter.

Example:

SW_OPER_STRCATT_1B_20140218T000000_20140218T235959_0301_MDR_SAT_AT.cdf

Where 03 is the Product Baseline number, while 01 is only an incremental File Counter.

The Product Baseline is increased when upgrades lead to significant improvements in the data quality of the related products. This subsequently leads to a reprocessing of the affected product types. Products with an older File Counter but same Product Baseline are erased.