The Eastern Weddell Sea Observation System (EWOS): A multinational initiative that provides coordinated and systematic observations of the Antarctic marine ecosystem

The Eastern Weddell Sea Observation System (EWOS) is an initiative to sample components of the Antarctic marine ecosystem through an international collaborative, multidisciplinary approach in order to characterize the ecosystem within a well-defined and diverse region in the Weddell Sea. The EWOS pilot study was carried out on the R/V Polarstern in March-April of 2022. There were three major components of EWOS that produced and interlinked physical, oceanographic, biogeochemical, ecological, biological, and physiological data over sea ice, water column, seafloor ecosystems. The approach of applying systematic observations has an important role to play in relation to (i) collecting information on Antarctic marine living resources and the ecosystems they are part of, and (ii) establishing baseline data enabling to distinguish natural variability from ecological change in the future. The EWOS pilot study demonstrated a potential approach that could be used for an international, interdisciplinary Long Term Ecological Research (LTER) Program in the Weddell Sea for ecosystem monitoring in the context of marine spatial planning and conservation activities.