Hyperspectral Non-water Absorption Coefficient (a_nw)

IOP | PACE Data Matchups

The hyperspectral non-water absorption coefficient (a_nw, units: m^-1) is defined as the total absorption coefficient (a) less the seawater absorption coefficient (aw). Hyperspectral anw quantifies light that is absorbed by non-water constituent matter. Field measurements of hyperspectral a_nw are routinely measured spectrophotometrically following the IOCCG Ocean Optics & Biogeochemistry Protocols for Satellite Ocean Colour Sensor Validation. PACE OCI derives hyperspectral of anw using the GIOP-DC* algorithm as a_nw = a_ph + a_dg.

*We note that GIOP-DC is currently for oceanic waters.

Non-water Absorption Coefficient (a_nw) Click to download data: Select a_nw matchup statistics \| Select a_nw matchups
Wavelength	Mean Bias	Limits of Agreement		Linear Slope	Linear Intercept	Linear Correlation	Rank Correlation	uRMSE [View plot]	MedAE [View plot]	Matchup Plots
Wavelength	Mean Bias	Low	High	Linear Slope	Linear Intercept	Linear Correlation	Rank Correlation	uRMSE [View plot]	MedAE [View plot]	Matchup Plots
anw_400	0.0309	-1.39	1.45	1.73	-0.524	0.847	0.896	0.68	0.153	Click here
anw_412	0.0894	-1.38	1.56	2.02	-0.576	0.839	0.915	0.659	0.144	Click here
anw_443	0.185	-1.46	1.83	3.15	-0.77	0.79	0.931	0.683	0.0896	Click here
anw_490	0.194	-1.6	1.99	7.35	-1.29	0.609	0.961	0.674	0.0475	Click here
anw_510	0.124	-1.56	1.81	10.8	-1.62	0.481	0.946	0.569	0.0404	Click here
anw_560	0.16	-1.67	1.99	21.3	-1.8	0.473	0.966	0.613	0.022	Click here
anw_620	0.17	-1.63	1.97	36.7	-2.12	0.367	0.896	0.606	0.0153	Click here
anw_665	0.171	-999	-999	49.7	-3.01	0.246	0.667	0.571	0.0174	Click here

Disclaimer: The unbiased RMESs and Median Absolute Errors shown in the hyperspectral plots are preliminary. Visitors should expect updated values over time due to incoming datasets with different spatial and temporal variability coverages and dynamic ranges, as well as to algorithm refinements.