Abstract: Particles in the ocean – ranging from microscopic to larger aggregates – marine snow are fundamental carriers of carbon, energy, and ecological interactions. I will present an in situ perspective on those aspects and what are the methodologies and technologies used by oceanographers for direct observations of particles in their natural environment. These include laser counters, underwater vision profilers, sediment traps, and autonomous platforms that resolve particle.

My work has been oscillating around explorations how particle dynamics vary across spatial and temporal scales and the processes that shape particles distribution, transformation, and ecological significance across diverse marine environments: Arctic (Svalbard, Greenland, Barents Sea), Antarctic, sub-Antarctic (Beagle Channel), Baltic, north Atlantic (Gulf Stream, Norwegian Sea), and Pacific (Monterey Bay). The presented examples of key processes governing particles dynamics include: 1) patchiness and mapping approaches that link particle distributions to food availability for higher trophic levels such as fish and seabirds, 2) vertical distribution governed by stratification, 3) particle & plankton co-existence,  4) classification of particles into morphocategories that reflect their origin and transformation pathways, 5) particle flux and sinking rates in relation to carbon export and ecosystem connectivity, 6) the effects of glacier melting o particle pools and transformations, including Arctic-Antarctic comparison, 7) resuspension of particles in kelp forest systems, and 8) seasonal variability in shaping particle abundance and composition.

By integrating observational techniques with process-based understanding, this lecture underscores the importance of particles as a unifying framework for studying marine ecosystems, and aims to stimulate new perspectives for discussion and collaboration.

Emilia Trudnowska is a professor at the Institute of Oceanology of the Polish Academy of Sciences (IOPAN). For over a decade, she has been studying the functioning of marine ecosystems in relation to environmental dynamics. She is mostly interested in the application of modern technologies and interdisciplinary research to provide new answers to old questions in marine science. The long-term research fellowships in Norway, France, and the USA greatly broadened her horizons and demonstrated the power of collaboration within diverse international teams. Emilia has received numerous research grants, gaining experience both as a principal investigator—including three grants funded by the National Science Centre (NCN) – and as a team member in national and international projects supported by NCN, the Ministry of Science and Higher Education (MNiSW), the National Centre for Research and Development (NCBiR), the Fulbright Program, Norwegian, European and US funds. She is the author or co-author of over 45 publications in international peer-reviewed journals. She has participated in 24 research expeditions, including 20 to the Arctic.