Vertical distribution of PAR and diffuse attenuation coefficient: modeling and in situ measurements

Vertical distributions of the photosynthetically available radiation, PAR, is of great importance for understanding of biological matter behavior, primary productivity estimation, heat budget evaluation and in some other problems. Numerical modeling of PAR penetration was carried out using a diffuse attenuation coefficient, Kd(440), in the upper 10 meters layer as an input parameter. These calculations were done for different types of the Kd(Z) profile. Numerical results are compared with experimental data of PAR. It is shown that the correlation between experimental and model PAR and Kd(440) in the upper 10 meters layer is very close.