NOAA STAR produces two lines of gridded 0.02deg super-collated L3S LEO datasets from Low Earth Orbiting (LEO) satellites, one from the NOAA afternoon JPSS (L3S_LEO_PM) and the other from the EUMETSAT mid-morning Metop-FG (L3S_LEO_AM). The L3S_LEO_PM is derived from JPSS satellites (in v2.80, NPP and N20) with VIIRS sensor onboard (0.75km/nadir). The L3S_LEO_PM dataset is produced by aggregating L3U datasets from two JPSS satellites ( https://doi.org/10.5067/GHVRS-3UO28 and https://doi.org/10.5067/GHV20-3UO28 ) and covers from Feb 2012-present. The L3S-LEO-PM data are reported in two files per 24hr interval, one daytime and one nighttime (nominal JPSS local equator crossing times around 01:30/13:30). Data is in NetCDF4 format, compliant with the GHRSST Data Specification version 2 (GDS2). The Near-Real Time (NRT) L3S-LEO data are archived at PO.DAAC with approximately 6 hours latency and then replaced by the Delayed Mode files about 2 months later, with identical file names. In addition to SST, the L3S-LEO files report the location and intensity of thermal fronts. The NRT/DM data are seamlessly stitched with the full-mission Reanalysis (RAN). The ACSPO L3S products are monitored and validated against in situ data in the NOAA iQuam system ( https://www.star.nesdis.noaa.gov/socd/sst/iquam ) in the NOAA SQUAM system ( https://www.star.nesdis.noaa.gov/socd/sst/squam ). Quality of SST imagery, clear-sky mask and thermal fronts is evaluated in the NOAA ARMS system ( https://www.star.nesdis.noaa.gov/socd/sst/arms ). NOAA plans to include data from other afternoon platforms and sensors, such as N21 and Aqua MODIS, into the future releases of the L3S_LEO_PM.

Grid processed for the purpose of the HR DTMs layer of EMODnet Bathymetry HRSM, October 2018

The SWOT L3_LR_SSH product provides ocean topography measurements obtained from the SWOT KaRIn and nadir altimeter instruments, merged into a single variable. The dataset includes measurements from KaRIn swaths on both sides of the image, while the measurements from the nadir altimeter are located in the central columns. In the areas between the nadir track and the two KaRIn swaths, as well as on the outer edges of each swath (restricted to cross-track distances ranging from 10 to 60 km), default values are expected. SWOT L3_LR_SSH is a cross-calibrated product from multiple missions that contains only the ocean topography content necessary for thematic research (e.g., oceanography, geodesy) and related applications. This product is designed to be simple and ready-to-use, and can be combined with other altimetry missions. The SWOT L3_LR_SSH product is a research-orientated extension of the L2_LR_SSH product, distributed by the SWOT project (NASA/JPL and CNES). SWOT L3_LR_SSH is managed by the SWOT Science Team project DESMOS. The ['Unsmoothed'] version of SWOT L3_LR_SSH (the "Basic" and "Expert" versions are the subject of separate metadata sheets) includes each algorithm, correction, or external model incorporated into the SWOT L3_LR_SSH product as a separate layer. This ['Unsmoothed'] version which includes the MSS, MDT and geostrophic currents (absolute and anomalies) in addition to the SSHA and MDT on the 250 m KaRIn native grid. Like the Expert subproduct, it also integrates a quality flag, corrections and external models as separate layers.

Level 3 hourly sub-skin Sea Surface Temperature derived from Meteosat at 0° longitude, covering 60S-60N and 60W-60E and re-projected on a 0.05° regular grid, in GHRSST compliant netCDF format. The satellite input data has successively come from Meteosat level 1 data processed at EUMETSAT. SST is retrieved from SEVIRI using a multi-spectral algorithm and a cloud mask. Atmospheric profiles of water vapor and temperature from a numerical weather prediction model, Sea Surface Temperature from an analysis, together with a radiative transfer model, are used to correct the multispectral algorithm for regional and seasonal biases due to changing atmospheric conditions.The quality of the products is monitored regularly by daily comparison of the satellite estimates against buoy measurements. The product format is compliant with the GHRSST Data Specification (GDS) version 2. Users are advised to use data only with quality levels 3, 4 and 5.

The ESA Sea State Climate Change Initiative (CCI) project has produced global multi-sensor time-series of along-track satellite altimeter significant wave height data (referred to as Level 2P (L2P) data) with a particular focus for use in climate studies. This dataset contains the Version 3 Remote Sensing Significant Wave Height product, which provides along-track data at approximately 6 km spatial resolution, separated per satellite and pass, including all measurements with flags, corrections and extra parameters from other sources. These are expert products with rich content and no data loss. The altimeter data used in the Sea State CCI dataset v3 come from multiple satellite missions spanning from 2002 to 2022021 (Envisat, CryoSat-2, Jason-1, Jason-2, Jason-3, SARAL, Sentinel-3A), therefore spanning over a shorter time range than version 1.1. Unlike version 1.1, this version 3 involved a complete and consistent retracking of all the included altimeters. Many altimeters are bi-frequency (Ku-C or Ku-S) and only measurements in Ku band were used, for consistency reasons, being available on each altimeter but SARAL (Ka band).

Level 3, four times a day, sub-skin Sea Surface Temperature derived from AVHRR on Metop satellites and VIIRS or AVHRR on NOAA and NPP satellites, over North Atlantic and European Seas and re-projected on a polar stereographic at 2 km resolution, in GHRSST compliant netCDF format. This catalogue entry presents Metop-B North Atlantic Regional Sea Surface Temperature. SST is retrieved from infrared channels using a multispectral algorithm and a cloud mask. Atmospheric profiles of water vapor and temperature from a numerical weather prediction model, Sea Surface Temperature from an analysis, together with a radiative transfer model, are used to correct the multispectral algorithm for regional and seasonal biases due to changing atmospheric conditions. The quality of the products is monitored regularly by daily comparison of the satellite estimates against buoy measurements. The product format is compliant with the GHRSST Data Specification (GDS) version 2.Users are advised to use data only with quality levels 3,4 and 5.