The main objectives of the Level-2 processing of LRM mode data is to provide re-tracked altimeter estimates (elementary and averaged estimates) of the ocean and ice sheet elevation, the backscatter coefficient (and wind speed over the ocean) and the significant wave height (over the ocean) together with geophysical corrections and environmental parameters.

The main objectives of the Level-2 processing of SAR mode data is to provide elementary re-tracked altimeter estimates of the ocean, coastal zones, ice sheet and sea-ice elevation, the backscatter coefficient (and wind speed over the ocean and coastal zones), the significant wave height (over the ocean and coastal zones) and the sea-ice freeboard, together with geophysical corrections and environmental parameters.

There are different re-tracking algorithms that are applied depending on the mode of operation (LRM or SAR). The different re-trackers can be more suited to a specific surface, and it is up to the final user to decide which one fits best for the final application:

• ocean re-tracking (open ocean and coastal zones)
• OCOG re-tracking
• ice sheet re-tracking
• ice re-tracking
• sea-ice re-tracking