True Color OLCI Sentinel-3A/B | NOAA CoastWatch & OceanWatch

Updated: July 19, 2021

Data are available through the following servers:
Service	Resource Locator
HTTPS	Near Real-time Search Granule selector tool (L2 unmapped): https://coastwatch.noaa.gov/cw_html/cw_granule_selector.html

The Sentinels are a suite of satellite missions developed to serve the operational needs of the European Copernicus program for Earth observations. NOAA CoastWatch/OceanWatch provides Sentinel data to US users through official arrangements with ESA, EUMETSAT and the European Commission.

Sentinel-3 is a multi-instrument mission to measure sea- and land-surface temperature, ocean and land color and sea-surface topography. Sentinel-3A was launched on 16 February 2016. Sentinel 3B was launched successfully on 25 April 2018 with the same instruments.

The Ocean and Land Colour Instrument (OLCI) is based on heritage from Envisat’s Medium Resolution Imaging Spectrometer (MERIS to measure visible and thermal infrared radiances, i.e., true color, ocean color and derived parameters such as chlorophyll, total suspended matter (TSM), diffuse attenuation coefficient at 490 nm (Kd(490)), absorption at 443 nm (a(443). OLCI has 21 bands at wavelengths from 400 nm to 1020 nm (400, 412, 442, 490, 510, 560, 620, 665, 674, 681, 709, 754, 779, 865, 885, 1024 nm), a spatial resolution of 300 m and a swath width of 1270 km.

See the ESA Sentinel-3 website^♦ for more information: http://www.esa.int/Our_Activities/Observing_the_Earth/Copernicus/Sentinel-3/Introducing_Sentinel-3^♦

OLCI Level 1b (e.g., true color) and ocean color Level 2 data (e.g., radiances, chlorophyll, etc.) are generated by EUMETSAT(https://www.eumetsat.int/website/home/Data/Products/Ocean/index.html^♦) and served by CoastWatch. CoastWatch also generates L3 mapped products for US Coastal regions.

OLCI true color products are generated from atmospheric corrected rho_s bands. Data are available in mapped 300m regions in near real-time CoastWatch HDF format and are compatible with the CoastWatch Utilities. The following variables are within the HDF dataset:

latitude	degrees
longitude	degrees
rhos_490
rhos_560
rhos_620
graphics

See the EUMETSAT ocean data product pages for more information and links to specific documents: https://www.eumetsat.int/website/home/Data/Products/Ocean/index.html^♦

(♦ - non-government website)

Key	Description
Platform/Sensor	Sentinel-3 / OLCI
Measurement/Products	true color
DOI	n/a
Short Name	OLCI True Color
Sample Filename	S3A_OL_1_EFR____20160831T093739_20160831T094039_20160831T114446_*.SEN3.tar OLCLCW.I2017158.153647.true300.hdf OLCKCW_I2021195_C1_181844_CC05_closest_true300.hdf
Dataset Type	n/a
Processing Level	Level-1B Level-3
Spatial Coverage	Global / Regions
Temporal Coverage	Near real-time data beginning: Level-1 released 20 October 2016
Latency	8 hours
Resolution	300 m
Projection	Swath Mercator: proj4text = +proj=merc +lon_0=0 +k=1 +x_0=0 +y_0=0 +datum=WGS84 +units=m +no_defs spatial_wkt = PROJCS["WGS 84 / World Mercator",GEOGCS["WGS 84",DATUM["WGS_1984",SPHEROID["WGS 84",6378137,298.257223563,AUTHORITY["EPSG","7030"]],AUTHORITY["EPSG","6326"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4326"]],PROJECTION["Mercator_1SP"],PARAMETER["central_meridian",0],PARAMETER["scale_factor",1],PARAMETER["false_easting",0],PARAMETER["false_northing",0],UNIT["metre",1,AUTHORITY["EPSG","9001"]],AXIS["Easting",EAST],AXIS["Northing",NORTH],AUTHORITY["EPSG","3395"]]
Swath Width	1270 km
Sample Frequency	n/a
Temporal Repeat	Orbital 27 days
Orbital Period	101 minutes
Orbit	Sun-synchronous (polar-orbiting), altitude 814.5 km, inclination 98.65 Equator crossing time at 10:00
Data Provider	NOAA CoastWatch/OceanWatch courtesy of Copernicus Program
Formats	NetCDF (tar file), HDF, PNG
Keywords	True Color, OLCI, Sentinel-3A/B, Copernicus, global, polar-orbiting