CERSAT

Naiad

Overview 

Naiad is a free software solution, written in python, whose aim is to provide Earth Observation users with an open-source, flexible and reusable tool to index and search within earth observation dataset the relevant data subsets matching user defined criteria. It is also used to detect cross-overs between different observation sources.

Homepage: https://naiad.gitlab-pages.ifremer.fr/naiad

Source code repository: https://gitlab.ifremer.fr/naiad/naiad

Description

Naiad python API allows to index Earth Observation data into a search engine such as Elasticsearch or into geoparquet files, and to perform then search queries on these indexes

Searching for Earth Observation (EO) data of interest is based in Naiad on the pre-indexing of these data as geospatial features, defined by:

  • the spatial boundaries (geometrical shape) covered by the feature
  • the time frame of the observations contained within the feature
  • the data object (file) containing the observations associated with the feature and the slicing information (if only a subset of a source data file is indexed, these are the dimensions along which this subset was sliced from the source data file)
  • any custom property labelling or describing the content of the feature, usable as a future search/selection criteria.

A feature may be a satellite image or swath or part of a swath, a trajectory or part of a trajectory, a grid or part of a grid, a series of locations,… corresponding to a data granule - a data structure stored as a whole in a file, a database record, etc…

Features are recorded within a geospatial index, corresponding to a given thematic and/or source product: it can be the indexing of a complete satellite file collection, or the indexing of subsets matching a specific interest (storm observations, etc…).

Usage

Naiad is used to systematically register large archive satellite observation data and to its users to later search and find the relevant granules or swath section matching their criteria of interest. It also allows the detection of cross-overs between different missions, for intercomparison and validation of their observations.
Naiad is also used at Ifremer/CERSAT to implement satellite data search and selection for external users through Opensearch and STAC services.

License

Naiad is available under the open source GPLv3 license.

Credits

Naiad is developed by Ifremer/CERSAT.