SeaWiFS Ocean Color Reprocessing 2022.0

Introduction

Reprocessing 2022.0 is a multi-mission reprocessing to incorporate updates in instrument calibration, vicarious calibration, new ancillary sources and algorithm improvements. The affected missions are CZCS, SeaWiFS, OCTS, MERIS, MODIS on Aqua and Terra, VIIRS on SNPP and NOAA-20, OLCI on Sentinel-3A and Sentinel-3B, GOCI, and HICO. Here we describe the results specific to SeaWiFS. There were no calibration changes in this reprocessing for SeaWiFS aside from a revised vicarious calibration to account for the multi-scattering epsilon change to the atmospheric correction.

Note: In February 2025, SeaWiFS L1A data was converted from HDF5 to netCDF4. The L2 and L3 data were subsequently reprocessed using the reformatted L1A files. However, this reprocessing did not introduce any changes to the final products, apart from the parent L1A files now being in netCDF format.

Results

Time Series Comparison

The comparison of the SeaWiFS time series for global deep water (>1000m) generated for the R2022 configuration to the corresponding R2018 time series is shown below (left panels). The ratio of R2022 to R2018 is also shown (right panels). Overall, the differences in Chlorophyll and remote sensing reflectance between R2018 and R2022 are small.

Comparison with In Situ Measurements

Validation of the chlorophyll, apparent optical properties (Rrs, Kd490), inherent optical properties (a_giop, aph_giop, adg_giop, bbp_giop), PAR, PIC, and POC retrievals was performed relative to all available match-ups from SeaBASS and the Aerosol Robotic Network - Ocean Color (AERONET-OC). Statistical analysis, scatter plots and frequency distribution comparisons of the satellite to in situ match-ups are provided below.

Chlorophyll a (chlor_a)

^* statistical calculations based on log10 (implies ignoring values equal to or less than zero)
Product Name	#	Mean Bias	Mean Absolute Error (MAE)	SeaWiFS Range	In situ Range
chlor_a	2270	1.07404^*	1.66383^*	0.01940, 300.49725	0.009, 138.04700

Apparent Optical Properties

Remote Sensing Reflectance (Rrs)

Product Name	#	Mean Bias	Mean Absolute Error (MAE)	SeaWiFS Range	In situ Range
Rrs412	2151	-0.00009	0.00136	-0.00395, 0.01980	0.00001, 0.02150
Rrs443	2489	-0.00004	0.00105	-0.00258, 0.02152	0.00007, 0.02227
Rrs490	2029	-0.00046	0.00094	-0.00069, 0.02697	0.00039, 0.03020
Rrs510	1037	-0.00025	0.00075	0.00048, 0.02702	0.00065, 0.03023
Rrs555	2145	-0.00039	0.00084	0.00089, 0.02627	0.00029, 0.03052
Rrs670	1595	-0.00009	0.00032	-0.00054, 0.01236	0.00002, 0.01090

Diffuse Attenuation Coefficients (kd490)

^* statistical calculations based on log10 (implies ignoring values equal to or less than zero)
Product Name	#	Mean Bias	Mean Absolute Error (MAE)	SeaWiFS Range	In situ Range
kd490	688	1.14673^*	1.35752^*	0.01966, 6.40000	0.00170, 1.80630

Inherent Optical Properties

Total Absorption Coefficients (a_giop)

^* statistical calculations based on log10 (implies ignoring values equal to or less than zero)
Product Name	#	Mean Bias	Mean Absolute Error (MAE)	SeaWiFS Range	In situ Range
a_giop412	302	0.92347^*	1.75333^*	0.01418, 2.61910	0.01119, 2.06813
a_giop443	302	0.87383^*	1.53631^*	0.01556, 2.43129	0.01177, 1.55735
a_giop490	302	0.82135^*	1.33673^*	0.02000, 1.53624	0.01707, 0.80774
a_giop510	302	0.86589^*	1.24734^*	0.03518, 1.27270	0.03396, 0.63838
a_giop555	302	0.91844^*	1.14711^*	0.02489, 0.83111	0.05983, 0.4090
a_giop670	302	0.93333^*	1.10831^*	0.04994, 1.88431	0.44098, 0.89216

Phytoplankton Absorption Coefficients (aph_giop)

^* statistical calculations based on log10 (implies ignoring values equal to or less than zero)
Product Name	#	Mean Bias	Mean Absolute Error (MAE)	SeaWiFS Range	In situ Range
aph_giop412	297	0.73569^*	1.75587^*	0.00009, 1.84905	0.00057, 0.30817
aph_giop443	302	0.81311^*	1.69451^*	0.00028, 1.98613	0.00075, 0.36954
aph_giop490	302	0.86385^*	1.64818^*	0.00019, 1.33298	0.00036, 0.25075
aph_giop510	302	0.85628^*	1.73937^*	0.00006, 1.10896	0.00013, 0.20075
aph_giop555	291	0.91812^*	1.88591^*	0.00005, 0.82529	0.00006, 0.10098
aph_giop670	302	1.04091^*	1.78792^*	0.00008, 1.43677	0.00022, 0.20921

Absorption Coefficient of Non-algal Material plus CDOM (adg_giop)

^* statistical calculations based on log10 (implies ignoring values equal to or less than zero)
Product Name	#	Mean Bias	Mean Absolute Error (MAE)	SeaWiFS Range	In situ Range
adg_giop412	301	0.87503^*	2.28397^*	0.00250, 2.26612	0.00539, 1.49709
adg_giop443	301	0.80043^*	2.37875^*	0.00143, 1.40316	0.00268, 0.96252
adg_giop490	301	0.66532^*	2.63639^*	0.00060, 0.75179	0.00105, 0.51651
adg_giop510	301	0.62244^*	2.75177^*	0.00044, 0.52449	0.00073, 0.39066
adg_giop555	301	0.52130^*	3.12199^*	0.00019, 0.23333	0.00004, 0.21688
adg_giop670	301	0.30274^*	4.42809^*	0.00009, 0.02945	0.00006, 0.05104

backscattering coefficient of particles (bbp_giop)

^* statistical calculations based on log10 (implies ignoring values equal to or less than zero)
Product Name	#	Mean Bias	Mean Absolute Error (MAE)	SeaWiFS Range	In situ Range
bbp_giop412	195	0.92548^*	1.51465^*	0.00014, 0.01112	0.00067, 0.04272
bbp_giop443	195	0.91610^*	1.49576^*	0.00014, 0.01025	0.00058, 0.03701
bbp_giop490	195	0.89594^*	1.47270^*	0.00014, 0.00912	0.00047, 0.03064
bbp_giop510	195	0.89171^*	1.46530^*	0.00014, 0.00870	0.00044, 0.02827
bbp_giop555	195	0.87839^*	1.45564^*	0.00014, 0.00801	0.00037, 0.02405
bbp_giop670	195	0.84646^*	1.47337^*	0.00014, 0.00719	0.00025, 0.01677