NASA's Earth Observing System Data and Information System (EOSDIS) data products are processed at various levels ranging from Level 0 to Level 4. Level 0 products are raw data at full instrument resolution. At higher levels, the data are converted into more useful parameters and formats.
Standard Data Products (SDPs) are an internally consistent, well-calibrated record of Earth’s geophysical properties to support science. They are made available within 8 to 40 hours of satellite observation. Some data products, such as near real-time data, are made available more quickly than standard processing to support users interested in monitoring a wide variety of natural and man-made phenomena. View more information about data latency.
All NASA Earth Observing System (EOS) instruments must have Level 1 SDPs; most have SDPs at Level 2 and Level 3; and many have Level 4 SDPs. Some EOS Interdisciplinary Science Investigations also have generated Level 4 SDPs.
Specifications for the set of SDPs to be generated are reviewed by the Earth Observing System Project Science Office (EOSPSO) and NASA Headquarters to ensure completeness and consistency in providing a comprehensive science data output. Standard data products are produced at NASA's Distributed Active Archive Centers (DAACs) or Science Investigator-led Processing Systems (SIPS).
| Data Level | Description |
|---|---|
| Level 0 | Reconstructed, unprocessed instrument and payload data at full resolution, with any and all communications artifacts (e.g., synchronization frames, communications headers, duplicate data) removed. |
| Level 1A | Level 1A (L1A) data are reconstructed, unprocessed instrument data at full resolution, time-referenced, and annotated with ancillary information. This ancillary information can include radiometric and geometric calibration coefficients and georeferencing parameters (e.g., platform ephemeris). |
| Level 1B | L1B data are L1A data that have been processed to instrument units (not all instruments have L1B source data). |
| Level 1C | L1C data are L1B data that include new variables to describe the spectra. These variables allow the user to identify which L1C channels have been copied directly from the L1B and which have been synthesized from L1B and why. |
| Level 2 | Derived geophysical variables at the same resolution and location as L1 source data. |
| Level 2A | L2A data contains information derived from the geolocated instrument data, such as ground elevation, highest and lowest surface return elevations, energy quantile heights (“relative height” metrics), and other waveform-derived metrics describing the intercepted surface. |
| Level 2B | L2B data are L2A data that have been processed to instrument units (not all instruments will have a L2B equivalent). |
| Level 3 | Variables mapped on uniform space-time grid scales, usually with some completeness and consistency. |
| Level 3A | L3A data are generally periodic summaries (weekly, 10-day, monthly) of L2 products. |
| Level 4 | Model output or results from analyses of lower-level data (e.g., variables derived from multiple measurements). |