High Latitude Sea and Ice Surface Temperature

Northern High Latitude L3 Sea and Sea Ice Surface Temperature

Operational Near real time product

Level 3 twice-daily sub-skin Sea and Sea-ice Surface Temperature derived from AVHRR on Metop, over northern high latitudes (Poleward of 50N) and re-projected on a polar stereographic at 5 km resolution four times a day, in GHRSST-like netCDF format. A similar product derived from VIIRS on NOAA exists.

Acronym : NHL L3 SST/IST
Product navigator reference :


OSI SAF producer : Norwegian Meteorological Institute
Identifier : OSI-203-a
Acronym for EDC (APNM) : OSSTIST3A
Citation : See at bottom
Processing level : L3
Satellite input : Metop-B/AVHRR
Other input : ECMWF outputs
Temporal sampling : 2 per day
Central time : 00:00, 12:00
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. 3h30
Spatial coverage : Poleward of 50N
Spatial sampling : 5 km
Projection : polar stereographic
File Formats : HL FTP Server (NetCDF4), EDC (NetCDF4), EUMETCast (NetCDF4)
Characteristics & methods : SST : subskin temperature. Multispectral algorithms
IST : skin temperature. Multispectral algorithms.
Probabilities of open water and sea ice. Single sensor analysis.
Data Access

OSI SAF FTP server (last 31 days)


Directory: sst/l3c

OSI SAF FTP server (archive)


Directory: sst/l3c

EUMETSAT Multicast

Accuracy Requirements
Target accuracy : SST absolute mean difference: 0.7 K, SST std: 1.0 K; IST absolute mean difference: 1.5 / 3.5 K, IST std: 2.0 / 3.0 K; PoD: 0.80 FAR: 0.20
Verification/validation method : SST : comparison with buoy measurements; IST: Comparison with buoy measurements on the ice, and IR radiometer when available; Comparison with high resolution manual ice charts
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 :
First date :
Full series temporal coverage : 2012-onwards
Citation : OSI SAF Northern High Latitude L3 Sea and Sea Ice Surface Temperature (Metop-B) 2019-onwards, OSI-203-a. 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...
  • Monthly accuracies.
    Include sea ice surface temperature and Sea Ice Probabilities.
    The IST accuracy requirements are split in two: the first is for validation against in situ IR radiometers, the second for in situ buoy data. The reason for this is discussed in the ATBD for OSI-205.

    Superseds OSI-203 from 03/04/2019, together with OSI-203-a.

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