Changes in plankton community structures in response to climate change and the climatic sensitivity of species are currently driving topics in marine ecology. It is expected that climate related environmental change could result in changes in the abundance, spatial distribution, biogeography or dominance of plankton species. This would strongly influence biogeochemical cycling, and also marine food webs up to top predators like fish or birds. Consequently there is a need for an assessment of the present state and teh expected changes within the marine plankton. Thus, the objective of the Helmholtz-University Young Investigator Group PLANKTOSENS, a co-operation of the AWI and the Jacobs University Bremen, is to provide important premises for the evaluation of climate change consequences at the base of marine food webs in Polar Regions and the North Sea. This involves the development of a smart observation strategy in order to cut down costs and effort involved in the observation of marine plankton and the assessment of the diversity in the marine plankton, including the pico- and nanoplankton.