The rain of lithogenic and biogenically produced particles from the surface ocean to the deep sea determines the distribution of biogeochemical elements, sustains mesopelagic and bathypelagic life, provides the source of sediments at the ocean floor and, ultimately, contributes to controlling the Earth’s climate. Their decay and remineralization as they sink through the water column govern the balances of oxygen, nutrients and other trace constituents. Lithogenic particles involved lateral transport on the continental margin usually dominate settling processes along with deepwater circulation. Understanding the factors that impact the efficiency of this biological pump is important to predict how particle export will evolve in the future. As the settling particles carry a memory imprint of the atmospheric, continental and upper ocean environments in which they were produced, extracting this memory is critical to understand and reconstruct past climatic and oceanographic conditions and to predict future trends.
Since the last workshop on material fluxes in the world oceans held 25 years ago in Hamburg, Germany, there has been considerable and rapid development of observational techniques and analytical methods for the quantification and modeling of particle fluxes, including particulate carbon, silica and related element fluxes through the water column and their sedimentary accumulation in relation to climate change. The dynamics of particle formation, sinking, remineralization, resuspension and/or sedimentation as a function of biological, physical and chemical forcing functions have been studied over variable time scales across the globe using moored, high-resolution time-series instrumentation, profiling floats/deep-sea drifters and other underwater technologies, sediment coring and state of the art laboratory techniques to improve our conceptual understanding of the processes regulating biogeochemical cycles. In particular, remote sensing has provided large-scale synoptic data sets enabling the extrapolation of regional studies to larger spatial and temporal scales, and linking atmospheric and surface ocean processes.
The proposed workshop will bring together professional and scientific experts under research themes related to biogeochemistry, sedimentology, atmospheric sciences, oceanography, modeling, and remote sensing to outline the current state of scientific and technical knowledge. The goal is to establish an improved understanding of the processes controlling biogeochemical cycling, to assess climatic feedbacks associated with changes in the chemical and physical environments and to identify and delineate future research steps.
The workshop will be organized into seven working themes: satellite observations, modeling, provenance/isotope studies, surface productivity/particle export, plankton ecology, transformations in the water column and at the water-sediment interface, and Anthropogenic contaminants (heavy metals/plastic).