Sentinel-2 data

Sentinel-2 is a constellation of Earth observation satellites, developed under the direction of the European Space Agency, as part of the European Commission's ambitious Copernicus Earth observation program. The full Copernicus program, which consists of several different Sentinel missions, is the most comprehensive systematic Earth Observation program ever created, providing land, ocean, and atmosphere observations, with continuity out to 2030. The wide-swath, multi-spectral imaging capabilities of the Sentinel-2 satellites provide an unprecedented view of our Earth, covering all of the Earth's land masses, large islands, and waterways.

Sentinel-2 data is ideal for agriculture, forestry, and other land management applications. For example, it can be used to study leaf area as well as chlorophyll and water content; to map forest cover and soils; and to monitor inland waterways and coastal areas. Images of natural disasters such as floods and volcanic eruptions can be used for disaster mapping and humanitarian relief efforts.

The Sentinel-2 mission consists of two identical satellites: Sentinel-2A, launched on June 23, 2015, and Sentinel-2B, launched on March 7, 2017. A third satellite, Sentinel-2C is scheduled to launch in 2024. With two satellites operational, the constellation is able to revisit each point on the Earth's surface every five days. Each satellite carries a Multi-Spectral Instrument (MSI) that produces images of the Earth with a resolution as fine as ten meters per pixel and spanning a 290 km field of view in thirteen bands across the visible and infrared.

Thanks to the free, full, and open data policy of the European Commission and European Space Agency, this dataset is available free as part of the Google Public Cloud Data program. It can be used by anyone as part of Google Cloud.

Dataset structure

These Sentinel-2 images are processed to Level-1C, which means they are orthorectified, map-projected images containing top-of-atmosphere reflectance data. See the Sentinel-2 User Guide for general information about Sentinel-2 and the Sentinel-2 Technical Guide for additional details.

The images are stored in the JPEG 2000 file format, with each spectral band stored as a separate image for easy access. Images are organized in the Sentinel-2 tiling grid, which is based on the Military grid reference system that divides the Earth into square tiles of approximately 100 km on each side. A single image tile acquired at a particular point in time is referred to as a "granule." Cloud Storage organizes granules in the following effective directory structure:

/tiles/UTM_ZONE/LATITUDE_BAND/GRID_SQUARE/GRANULE_ID/...

Where the components of this path are:

  • UTM_ZONE: A number indicating the longitude zone in the Universal Transverse Mercator (UTM) system.
  • LATITUDE_BAND: A letter in the range "C" through "X" (omitting "I" and "O") which indicates the latitude band.
  • GRID_SQUARE: A two-letter code indicating the particular 100 km square region.
  • GRANULE_ID: The Sentinel-2 id of a particular granule, which contains images of this grid square at some point in time.

For example, all Sentinel-2 granules over one particular GRID_SQUARE in eastern Germany can be found here:

gs://gcp-public-data-sentinel-2/tiles/33/U/UP/

Within the GRANULE_ID directory, the granule images and associated metadata are organized according to the Standard Archive Format for Europe (SAFE). Each GRANULE_ID directory contains a subdirectory named GRANULE that holds the granule data itself, along with additional metadata associated with the product that this granule belongs to. (This directory structure reflects the fact that the European Space Agency is currently transitioning away from distributing granules grouped in products and towards distributing granules individually.)

There are three subdirectories within the granule itself:

  • IMG_DATA/: Contains the actual image data in thirteen JPEG 2000 files (one for each spectral band).
  • QI_DATA/: Contains quality control reports for this granule.
  • AUX_DATA/: Contains ECMWF weather forecast data for this granule.

Dataset access

The image data can be used easily with any software that recognizes JPEG 2000 image files. The additional metadata files can be used with the Sentinel-2 Toolbox, an open source toolbox developed for the European Space Agency (ESA). This toolbox includes visualisation, analysis, and processing tools for Sentinel-2 data.

To help locate data of interest, an index CSV file of the sentinel-2 data is available. This CSV file lists the available granules, their acquisition dates, and their spatial extent as minimum and maximum latitudes and longitudes. The file is found in the Sentinel-2 Cloud Storage bucket:

gs://gcp-public-data-sentinel-2/index.csv.gz

Alternatively, this index data is available in BigQuery for you to easily query using SQL. Note that to use BigQuery, you must have a user account and create a Google Cloud project.

Google Earth Engine

One way that you can query, visualize, and analyze the Sentinel-2 data is by using Google Earth Engine, where the data is available in the image collection with id COPERNICUS/S2.

About the dataset

Dataset Source: European Commission (Copernicus), ESA.

Category: Satellite imagery, Geo.

Use: Sentinel data is free, full and open for public use under EU law. For full details of use, refer to the Copernicus Sentinel Data Terms and Conditions.

Update Frequency: New Sentinel-2 scenes are added daily as they become available. Data is typically available 1-2 days after publishing by Copernicus. There may occasionally be additional delays due to planned or unplanned maintenance.

Format: JPEG 2000, plus ancillary data.

Cloud Storage Location: gs://gcp-public-data-sentinel-2 (located in the EU multi-region).