Award: OCE-1459513

In this project, we measured the rare earth elements (REEs) and neodymium (Nd) isotopes in a return transect from the Bering Strait to the North Pole and back. This effort was part of a larger international GEOTRACES effort to map the distributions of such trace elements and isotopes in the global oceans. In conjunction with the other data collected in this and other GEOTRACES cruises, these REE and Nd isotope data will be used to understand the processes that control trace element distributions in the oceans, to better constrain the deep circulation of this region and to use this information collectively to better understand the oceanography and environment of the Arctic. The Arctic is a unique and paradoxically fragile environment: the ecology, peoples and culture of the Arctic have evolved in a balance with strong seasonality and patterns of oceanography/climate that are particularly prone to change from external forcing. Our data will be used to try and develop a better model of where the likely points of failure are in this system that may result from human or natural pressure. The link between REE and Nd isotope data and such a goal may seem tenuous but are in fact rather straightforward. For example, Nd isotopes appear to be good tracers of ocean circulation, which is key to understanding the interplay between the Pacific and Atlantic waters that meet in the Arctic, or how deep basin water may or may not become corrosive or hypoxic. The REEs, likewise have links to the biology and chemistry of sinking particles and/or benthic sources which can be associated with sea ice dynamics, biologic productivity and water oxygenation. Thus, while the data that we have generated seem rather esoteric in nature they are very useful tools in understanding broader environmental processes in the Arctic. Our efforts in this project are multi-institutional, nested in the greater multi-national efforts to generate a global database of these elements and isotopes. As such, the data is rich with intricacies and nuance - both internal to the Arctic sections, but more so through comparison with other ocean basin data. The complexity of the science increases as the databases grow, but this is the path towards a more holistic understanding of the processes governing marine biogeochemistry. The Arctic data collected in this project will continue to move us towards this ultimate goal. This project has supported research science at Oregon State University, including a lab technician and undergraduate assistants. This project helped to continue the strong inter-institutional collaborations - both nationally and internationally - that foster scientific and cultural understanding and cooperation. The project also helped to support the US sea-going science venture, which makes manifest the sense of exploration and curiosity characteristic of US science. Last Modified: 10/09/2019 Submitted by: Brian A Haley