- In this paper we review the concept of “Laser Firefly Clusters” for atmospheric probing and describe the development of the first and second generation versions. The laser firefly cluster is a mobile and versatile distributed sensing system with the purpose of profiling the chemical and particulate composition of the atmosphere on the basis of its optical properties. The primary applications are pollution monitoring, and detection of contamination as well as scientific research, meteorology and others. In this paper we extend the concept from the atmospheric to the oceanic environment and introduce “Optical Plankton”. The special features of the ocean as a channel for optical wireless communication are characterized and the distinctive requirements of monitoring the oceanic particulate composition are addressed.