Ongoing Projects

Investigating the Role of Mesoscale Processes and Climate-Sensitive Ice Dynamics in
Carbon and Iron Fluxes of the Amundsen Sea

Lead PI: Pierre St-Laurent, Old Dominion University

Funding source: NSF Antarctic Organisms and Ecosystems

Description: We are using data from an expedition to the Amundsen Sea Polynya, west
Antarctica to inform the construction of a high-resolution physical/biogeochemical model of this
very interesting and productive body of water that supports an abundant ecosystem every
summer. We continue to use our mass spectrometry facility to analyze samples from our very
large archive. The goal is to generate a predictive model that tell us how the limiting nutrient
iron (Fe) is supplied to the system, and to use these predictions to plan a future field investigation
on a return to Antarctica.

GEOTRACES Arctic section: Dissolved micronutrient trace metal distributions and size
partitioning (Fe, Mn, Zn, Cu, Cd, and Ni)

Lead PI: Jess Fitzsimmons (former Sherrell group postdoc, now at Texas A&M)

Funding source: NSF Chemical Oceanography

Description: How do trace elements and their isotopes move around the Arctic Ocean and what
controls their distribution and behavior, in the context of ongoing sea ice loss in this region?
This is the goal of the US GEOTRACES Arctic expedition, which took place in 2015, reaching
the North Pole from the Bering Strait. We are collaboratively analyzing seawater samples for six
dissolved and colloidal trace metals to acquire basic information that has never been available
before. Our first publication will describe the Zn distribution and the biogeochemical processes
that are active in the Arctic.

Investigation of paired uranium and chromium isotope behavior during authigenic metal
uptake into continental margin sediments

Lead PI: Silke Severmann

Funding source: NSF OCE Division Of Ocean Sciences