Sea Surface Temperature

Satellite SST is the longest and most mature application of ocean remote sensing. Passive observations are made with infrared (IR) sensors onboard multiple polar-orbiting and geostationary platforms, and microwave sensors onboard polar platforms. The IR sensors have higher spatial (1-4km) and temporal (10-15min, onboard geostationary satellites) resolution, and superior radiometric performance. However, IR sensors cannot "see through cloud", thus typically limiting retrievals to ~20% of the global ocean, whereas microwave sensors may see through clouds (except heavily precipitating) and therefore have higher coverage, but have coarser spatial resolution (~20-50km) and radiometric performance, cannot be used in coastal and marginal ice zone areas, and may be subject to other errors (due to e.g. radio frequency interference, RFI)

NOAA produces several L2 (Level 2) (original swath), L3 (gridded), and L4 (gap-free analysis) SST products in international Group for High-Resolution SST (GHRSST) Data Specifications version 2 (GDS2) and makes them available from NOAA CoastWatch:

VIIRS (SNPP) Level 3

Product Families
Sea Surface Temperature
Summary

NOAA CoastWatch / OceanWatch / PolarWatch produces Level 3 sea surface temperature datasets using the VIIRS sensor aboard the SNPP satellite. 

AVHRR (MetOp-1/2) Level 2/3

Product Families
Sea Surface Temperature
Summary

NOAA CoastWatch / OceanWatch / PolarWatch produces Level 2/3 sea surface temperature datasets using AVHRR sensors aboard the Metop 1/2 satellites. 

NOAA Geo-Polar Blended Global Sea Surface Temperature Analysis (Level 4)

Product Families
Sea Surface Temperature
Summary

The NOAA geo-polar blended SST is a daily 0.05° (~5km) global high resolution satellite-based sea surface temperature (SST) Level-4 analyses generated on an operational basis. This analysis combines SST data from US, Japanese and European geostationary infrared imagers, and low-earth orbiting infrared (U.S. and European) SST data, into a single high-resolution 5-km product.  The three flavors of blended SST products are night only; day/night, and diurnal warming. 

ACSPO Global SST from VIIRS

Product Families
Sea Surface Temperature
Summary

These VIIRS SST data are produced using the NOAA Advanced Clear-Sky Processor for Ocean (ACSPO) SST system, from the afternoon NPP, N20 and N21 satellites, in two formats: L2P and L3U (uncollated). The data are reported in 10 min granule files in NetCDF4 format, compliant with the GHRSST Data Specifications v2 (GDS2). For each satelite, there are 144 granules per 24 hr interval, with a total data volume of ~7.1 GB/day for L2P, and ~0.4 GB/day for L3U.

ACSPO Global SST from MODIS

Product Families
Sea Surface Temperature
Summary

The ACSPO MODIS SST data are produced from Terra and Aqua satellites using the NOAA Advanced Clear-Sky Processor for Ocean (ACSPO) enterprise system (Ignatov et al., 2016). Complete archive of ACSPO MODIS SST data is available for both the Terra (24 Feb 2000 - present) and Aqua (4 July 2002 - present) missions in 0.02° L3C (level 3 collated) format. New data is added in delayed mode (DM) with a 2-month latency.  The last orbital maintenance maneuvers for Aqua and Terra were performed on 27 Feb 2020 (Terra) and 18 Mar 2021 (Aqua) and their orbit has been drifting ever since. We do not recommend usage of ACSPO MODIS SST dated a year or later after each satellites' last orbital maintenance maneuver. For more recent SST data from low earth orbit satellites, we recommend the ACSPO VIIRS and AVHRR FRAC datasets.

ACSPO Global SST from AVHRR GAC

Product Families
Sea Surface Temperature
Summary

AVHRR GAC Reanalysis 2 (RAN2) dataset is an improved and extended version of AVHRR GAC RAN1 (Ignatov et al., 2016). RAN2 is produced from 5 AVHRR/2s (onboard N07/09/11/12/14) and 5 AVHRR/3s (N15/16/17/18/19) using the NOAA Advanced Clear-Sky Processor for Ocean (ACSPO) enterprise system v2.81. At the time of release, it covers from 1 Sep 1981 to 31 Dec 2021 and will be periodically extended as new L1b data from N15/18/19 arrive. Out of ten satellites, seven (N07/09/11/14/16/18/19) were initially launched into afternoon orbits (1:30pm/am), two (N12/15) into early-morning orbits (7:30pm/am), and one (N17) into mid-morning orbit (10am/pm). All NOAA orbits are not controlled and evolve in time. The RAN2 dataset is documented in (Petrenko et al. 2020 and 2021; Pryamitsyn et al. 2020)

ACSPO Global SST from AVHRR FRAC

Product Families
Sea Surface Temperature
Summary

The AVHRR FRAC SST data are produced from AVHRR/3s onboard Metop-A, -B and -C satellites using the NOAA Advanced Clear-Sky Processor for Ocean (ACSPO) v2.80 enterprise system, described in (Ignatov et al., 2016). Currently, near-real time (NRT) L2P and  0.02° L3U (gridded uncollated) data for Metop-A, -B and -C is produced at STAR (with ~2 to 6hrs latency). The data are being archived at PO.DAAC, and also available at this CoastWatch page as a 2 weeks rotated buffer. Metop-A mission officially ended at 2021-11-15 and the production of the ACSPO SST for the Metop-A ended at 2021-11-14 due to data degradation on 2021-11-15. 

ACSPO Global SST from AHI

Product Families
Sea Surface Temperature
Summary

The AHI SST data are produced from Himawari-9 (Himawari-8 before 2022-Dec-13) geostationary satellite using the NOAA Advanced Clear-Sky Processor for Ocean (ACSPO) v2.90 enterprise system,(ACSPO v2.70 was used for Himawari-8). Currently, only near-real time (NRT) data are produced at STAR, with a 2-6 hour latency (typically closer to 2 hours). The data are available in NetCDF4 format, compliant with the GHRSST Data Specifications v2 (GDS2). The data for Himawari-8  was archived with PO.DAAC with start date 2019-Oct-16 and end date 2022-Dec-13. The  PO.DAAC archival of the Himawari-9 will start soon. The data is also available at this Coast Watch page as a 2week rotated buffer. There is a plan to reprocess the AHI data, for the full Himawari-8 and -9 missions.

ACSPO Global SST from ABI

Product Families
Sea Surface Temperature
Summary

The ABI SST data are produced from GOES-East (GOES-16) and GOES-West (at present GOES-18, before 2023/01/10 GOES-17) satellite using the NOAA Advanced Clear-Sky Processor for Ocean (ACSPO) v2.xx enterprise system. Currently, near-real time (NRT) data are produced at STAR, with a ~2-6 hour latency. A Reanalysis (RAN) dataset for GOES-16 is also available. The data are available in NetCDF4 format, compliant with the GHRSST Data Specifications v2 (GDS2). Currently, the data are archived on PO.DAAC and available at this Coast Watch page as a 2week rotated buffer.

NOAA CoastWatch MA Monitor

Monitor Type
Data Assurance
Description

The NOAA CoastWatch MA Monitor provides the real-time delivery status of all Moderate Assurance (MA) products.

SST Quality Monitor (SQUAM)

Monitor Type
Quality Assurance
Description

SQUAM monitors global L2 & L3 SSTs with respect to L4 fields & in situ data. It also intercompares and validates various global L4 SST products.

In Situ SST Quality Monitor (iQuam)

Monitor Type
Quality Assurance
Description

iQuam is a system developed in NESDIS/STAR to perform near real time QC of in situ measurements and monitor the statistics. Ships and buoys (drifters and moorings) are included.

OceanWatch Monitor

Monitor Type
Data Assurance
Quality Assurance
Description

This OceanWatch Monitor provides an easy way for CoastWatch users to assess the state of the available products at one location (under one URL). The current capability includes monitoring of five different environmental data record (EDRs): Ocean Color (OC) Chlorophyll-a, Sea Surface Height (SSH), Sea Surface Salinity (SSS), Sea Surface Temperature (SST) and Sea Surface Wind (SSW) aka Ocean Surface Vector Wind. The OM framework is flexible to accommodate newer products for existing EDRs, and scalable for adding a newer EDR. Besides product monitoring within a given EDR family, it is envisioned to allow a joint analysis of different EDRs under an inter-thematic module. However, not all available CW products have been included in the monitor yet and this will be done incrementally. Likewise, the various data sets may have different latencies depending on their scientific needs.  See Quickstart Userguide for more information.

CoastWatch Data Quality & Availability Dashboard

Monitor Type
Data Assurance
Quality Assurance
Description

This Data Availability Dashboard gives a concise report of product availability and a quick look at a bulk time series to monitor for product stability

CDN Moderate Assurance Monitor

Monitor Type
Data Assurance
Description

The CDN Moderate Assurance Monitor displays a daily report for current and past availability of all Moderate Assurance (MA) products. 

Seviri (MSG) - Geostationary - Level 3

Product Families
Sea Surface Temperature
Summary

The National Oceanic and Atmospheric Administration's Office of Satellite Data Processing and Distribution are generating operational sea surface temperature (SST) retrievals from the Geostationary Operational Environmental Satellites GOES-East and West. The generation of SSTs began with GOES-8 in 2000 and has continued to be generated through GOES-15

NOAA CoastWatch co-gridded VIIRS SST from ACSPO

Product Families
Sea Surface Temperature
Summary

NOAA CoastWatch co-gridded VIIRS SST products are Level 3 daily composites in compatible format and projection with other CoastWatch Level 3 sector and global products (such as CoastWatch sector VIIRS ocean color).  Twenty four CoastWatch sector files mapped to equatorial projection that cover the globe (see Description tab for sector definitions) two polar stereographic sectors in 750 m nominal, native resolution and a global, 4 km resolution, single file mapped product is also available. These CoastWatch Level 3 products are generated from ACSPO L2P SST as input.

ACSPO Global 0.02º Gridded Super-collated SST and Thermal Fronts from Low-Earth-Orbiting Platforms (L3S-LEO)

Product Families
Sea Surface Temperature
Summary

NOAA Advanced Clear-Sky Processor for Ocean (ACSPO) L3S-LEO SST is a family of multisensor gridded ("L3") 0.02º resolution super-collated ("S") products. The L3S-LEO family is organized into three lines: PM, AM and Daily. The AM and PM lines correspond to 9:30am/pm and 1:30am/pm equator crossing times, respectively. The Daily line combines PM and AM (day and night) SSTs into a single daily L3S SST that is normalized to 1:30am viewing conditions.