AVHRR GAC Sea Surface Temperature Reanalysis Version 2

The 40+ years-long sea surface temperature (SST) dataset from 4 km Global Area Coverage (GAC) data of the Advanced Very High-Resolution Radiometers (AVHRR/2s and/3s) flown onboard ten NOAA satellites (N07/09/11/12/14/15/16/17/18/19) has been created under AVHRR GAC SST Reanalysis 2 (RAN2) Project. were reprocessed with Clear Sky Processor for Ocean (ACSPO) enterprise system. Two products are reported in full ~3000 swath: ‘subskin’ (highly sensitive to true skin SST, but debiased respect situ SST) and ‘depth’ (a closer proxy data, reduced sensitivity). reprocessing methodology aims at close consistency satellite SSTs SSTs, an optimal retrieval domain. Long-term orbital calibration trends compensated by daily recalculation regression coefficients using matchups drifters tropical moored buoys (supplemented ships N07/09), collected within limited time windows centered processed day. nighttime Sun impingements on sensor black body mitigated correcting L1b coefficients. Earth view pixels contaminated a stray light excluded. Massive cold outliers caused volcanic aerosols following three major eruptions filtered out modified, more conservative ACSPO clear-sky mask. RAN2 available formats: swath L2P (144 10-min granules per 24 h interval) two 0.02° gridded (uncollated L3U, also 144 granules/24 h; collated L3C, global maps h, one day night). This paper evaluates dataset, focus L3C product compares it other datasets, Pathfinder v5.3 ESA Climate Change Initiative v2.1. Among covers ocean completely shows regional temporal biases, improved stability between different satellites, SSTs.