High Latitude L2 Sea and Sea Ice Surface Temperature

Operational Near real time product

Level 2 sub-skin Sea and Sea-ice Surface Temperature derived from radiometers on low earth orbit satellites, over northern high latitudes (Poleward of 50N) and provided in full-resolution swath (1 km at nadir), in GHRSST-like netCDF format.

Acronym : HL L2 SST/IST
Product navigator reference :


OSI SAF producer : Norwegian Meteorological Institute
Identifier : OSI-205-b
Citation : See at bottom
Processing level : L2
Satellite input : NPP/VIIRS
Temporal sampling : Up to 15 files/day
Central time : NA
Timeliness : ? The timeliness is the time elapsing from the sensing time of the last contributing file to the product dissemination to users. It is similar to the latency. 3h
Spatial coverage : Poleward of 50N
Spatial sampling : 1 km
Projection : Swath
File Formats : HL FTP Server (NetCDF4), EDC (NetCDF4), EUMETCast (NetCDF4)
Characteristics & methods : The product consists of Sea and Sea Ice Surface temperatures (SST and IST) and an unvalidated test temperature field, Land Ice Surface Temperature (LIST) for the Greenland and Antarctic ice caps. SST is subskin temperature, IST is skin temperature.
The temperature is retrieved using a multispectral algorithm and a cloud mask, using the PPS software from the NWC SAF.
The product covers the sea and ice areas polewards of latitudes 50N with 3-minute data segments in Level 2, with data processed and archived continuously throughout the day, as they become available (approximately 110 3-minute segments per day per hemisphere). The product is derived from NPP/VIIRS data and includes uncertainties.
Data Access

OSI SAF FTP server (last 31 days)

Directory: sst/l2p_viirs

OSI SAF FTP server (archive)

Directory: sst/l2p_viirs

EUMETSAT Multicast

Accuracy Requirements
Target accuracy : SST absolute mean difference: 0.7 K, SST standard deviation: 1.0 K; IST absolute mean difference: 1.5 / 3.5 K, IST standard deviation: 2.0 / 3.0 K
Verification/validation method : SST: Comparison with buoy observations. IST: IST: comparison IR radiometer when available and with buoy measurements on the ice
Applications and users
Usage : * Operational Met Services,
* Operational analyses and ocean models,
* Research or Environmental monitoring
Authorised to be operational / released :
Declared operational / released since :
On EUMETCast since :
On EDC since :
On FTP server since :
Expected date for operational/released :
First date :
Full series temporal coverage : 2016-onwards
Citation : OSI SAF High Latitude L2 Sea and Sea Ice Surface Temperature (NPP) 2019-onwards, OSI-205-b. EUMETSAT Ocean and Sea Ice Satellite Application Facility. Data extracted from [distributor/distribution mean]: ([extracted period],) ([extracted domains],) accessed [download date]

The content within square brackets "[…]" is to be replaced with whatever distributor, period, domain or download date is relevant to the data being used. The "extracted period" and "extracted domains" are only needed if a subset of the data is being used.
Suggestions for "distributor/distribution mean": OSI SAF FTP server/the EUMETSAT Data Centre/EUMETCast/name and URL of a redistributor...
  • See also OSI-205-a (same product but based on Metop-B data)

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