Light scattering data measured in various sites ranging from open ocean to coastal and harbor waters have been analyzed. The dependence of scattered light intensity on scattering vector shows two distinctive q regions. This I(q) behavior is consistent with the two component model of sea particle size distribution. The average particle fractal dimensions estimated from these data are 1.7 +/- 0.1 for small q values (q less than or equal to 2.5 mu m(-1)) and 2.7 +/- 0.4 for large q values. These fractal dimensions correspond to cluster-cluster aggregation of larger (B component) particles due to differential sedimentation and to shear induced particle-cluster aggregation of smaller (A component) particles. They also agree with the fractal properties of microaggregates obtained from the recent simulation of phytoplankton bloom in a mesocosm.