# Quantifying Uncertainties in OC-SMART Ocean Color Retrievals: A Bayesian Inversion Algorithm
## 3 Methodology for Quantifying Uncertainties
### Application to Other Sensors  
The methodology laid out above can easily be applied to other ocean color sensors. Modifications to the experimental setup described in Section 3.5 are minor and include modifying the forward model to be suitable for a specific sensor and adjusting the wavelength bands and APEs. Shown here are results from the OLCI Sentinel-3 sensor off the Iberian peninsula (Figures 11 and 12) and the VIIRS sensor over the Atlantic ocean (Figures 13 and 14). Similar to MODIS sensor data in Figure 8, OLCI sensor data in Figure 11 show elevated green bands for optically complex coastal water. In this case, run-off from two prominent rivers lead to the results for ST8 while larger blue band values are observed in the open ocean region of ST9. A compilation of \(R_{\rm rs}\) estimate retrievals and uncertainties for this region are provided in Figure 12. In the RGB image of Figure 13, VIIRS sensor data for ST10 and ST11 closely match those of ST2 and ST3 in Figure 5. Despite the presence of sunlight in the region \(R_{\rm rs}\) retrievals and uncertainties are largely unaffected as can be seen in Figure 14.  
Figure 11: (**Left panel**) Locations of interest near the Iberian peninsula on 2I January 2022. ST8 (red) is located in the Golfo de Cadiz near the delta of two prominent rivers, ST9 (black) is located west of Lisbon. (**Right panel**) \(R_{\rm rs}\) from OLCI Sentinel-3 sensor data with uncertainties for two locations of interest for several wavelengths.  
Figure 12: Remote sensing reflectance data from OLCI Sentinel-3 sensor (**Left**), corresponding standard uncertainties (**Center**), and relative uncertainty (**Right**) for several wavelengths near the Iberian peninsula on 21 January 2022.  
Figure 13: (**Left panel**) Locations of interest off Northeast coast of the United States on 2 May 2021. ST10 (red) is located south of Nova Scotia in optically complex waters, ST11 (black) is located in an open region of the Atlantic ocean. (**Right panel**) \(R_{\rm rs}\) from VIIRS sensor data with uncertainties for two locations of interest for several wavelengths.  
The locations of interest shown for various regions and several sensors are intended to provide insight on a variety of water conditions beyond the open ocean where OC-SMART and other AC algorithms perform best. The OC-SMART approach currently uses a large ensemble of IOP realizations in order to represent open ocean water, as well as turbid coastal waters. It is designed to provide a smooth, seamless transition between clear open ocean and turbid coastal waters. Although adequate for many coastal regions, additional IOP data may be needed to obtain more accurate results in some optically complex coastal regions. To improve the performance of OC-SMART in such regions, more IOP data could be added to improve the response/output of OC-SMART. Introducing additional IOP modeling data is also expected to improve the uncertainty estimations discussed in this paper as it would allow use of more adaptive _a priori_ assessments and measurement error calculations.  
Figure 14: Remote sensing reflectance data from VIIRS sensor (**Left**), corresponding standard uncertainties (**Center**), and relative uncertainty (**Right**) for several wavelengths off the Northeast coast of the United States of America on 2 May 2021.