Sensitivity Assessment on Satellite Remote Sensing Estimates of Primary Productivity in Shelf Seas

Abstract

The vertically generalized production model (VGPM) is one of the most important methods for estimating marine net primary productivity (PP) using remote sensing. However, different data sources and parameterization schemes of the input variables for the VGPM can introduce uncertainties to the model results. This study compared the PP results from different data sources and parameterization schemes of three major input variables (i.e., chlorophyll-a concentration (Copt), euphotic depth (Zeu), and maximum photosynthetic rate (PoptB)) and evaluated the sensitivity of VGPM in the Yellow and Bohai Seas on the inputs. The results showed that the sensitivity in the annual mean PP was approximately 40%. Seasonally, the sensitivity was lowest in the spring (35%), highest in the winter (70%), and approximately 60% in the summer and autumn. Spatially, the sensitivity in nearshore water (water depth PoptB and Copt was important for the magnitude of annual mean PP. The PP seasonal variation pattern was highly related to the parameterization scheme of PoptB, whereas the spatial distribution was mostly sensitive to the data sources of Copt.

Keywords

• shelf sea
• marine primary productivity
• satellite remote sensing
• chlorophyll-a