JPSS VIIRS SST Reanalysis Version 3

The 3rd full-mission reanalysis (RAN3) of global sea surface temperature (SST) with a 750 m resolution at nadir is available from VIIRS instruments flown onboard two JPSS satellites: NPP (February 2012–present) and N20 (January 2018–present). Two SSTs, ‘subskin’ (sensitive to skin SST) ‘depth’ (proxy for in situ SST depth 20 cm), were produced brightness temperatures (BTs) the bands centered 8.6, 11 12 µm during daytime an additional 3.7 band night, using NOAA Advanced Clear Sky Processor Ocean (ACSPO) enterprise system. RAN3 dataset fully archived NASA JPL PO.DAAC CoastWatch, routinely supplemented near real time (NRT) latency few hours. Delayed mode (DM) processing 2 months follows NRT, resulting more uniform science quality record. This paper documents evaluates performance dataset. Comparisons SSTs drifters tropical moorings (D+TM) as well Argo floats (AFs) (both iQuam system) show good agreement, generally within specifications accuracy (±0.2 K) precision (0.6 K), clear-sky domain covering 18–20% ocean. nighttime compare data closely, expected due reduced diurnal thermocline. are also specs but some differences between AF validations residual drift on order ?0.1 K/decade. BT comparisons VIIRSs MODIS-Aqua consistency bands. band, while consistent N20, shows respect MODIS-Aqua. Similar analyses 8.6 inconclusive, MODIS 29 degraded unstable cannot be used comparisons.