2023-2024: Ocean Sciences: Virginia (Ginger) Armbrust

Virginia (Ginger) Armbrust
University of Washington


Virginia (Ginger) Armbrust is the Richard H. Fleming Endowed Professor of Oceanography at the University of Washington.  Her research focuses on the molecular ecology and physiology of marine phytoplankton as these microscopic organisms are responsible for about half the organic matter and oxygen generated on Earth each year. She studies the interactions between phytoplankton and other microbes and with their environment. Her lab combines laboratory experiments with field studies to understand how different forces shape the diversity and productivity of marine microbial communities in current and future oceans.  Her work incorporates molecular and optical-based approaches with model organisms in the lab and natural communities at sea.  Her lab group invented a ship-board instrument that generates fine scale maps of phytoplankton abundance and growth rates and has developed new software tools as needed.  She has decades of experience conducting research at sea and in recent years has led several multi-lab research cruises in the North and Equatorial Pacific Ocean.

Armbrust is a Fellow of the American Geophysical Union (AGU), the American Association for the Advancement of Sciences (AAAS), the American Academy of Microbiology, and is a member of the Washington State Academy of Science.  She has received awards from the Botanical Society of American and the Phycological Society for her research on phytoplankton.  She served for 8 years as the Director of the School of Oceanography at the University of Washington.  She received her BA from Stanford University and her PhD from Massachusetts Institute of Technology and Woods Hole Oceanographic Institution.  Prior to joining the faculty at the University of Washington, she was a postdoctoral researcher at Washington University where she trained in molecular genetics.

Abstract: The Hidden Worlds of Marine Microbes

Every drop of seawater is home to fantastically diverse groups of microscopic organisms that together control key biogeochemical processes in the ocean and determine the habitability of our planet. The challenge is to scale from this microscopic world of individual cells to ecosystem function and ultimately to ocean basin processes.  I will focus on microbial processes that occur within the lighted portion of the ocean as this is where the phytoplankton generate nearly half the organic carbon produced on Earth each year. This organic matter is the basis for much of life in the oceans, from the smallest bacteria to the largest whales.  In coastal waters, a group of phytoplankton known as diatoms form the base of highly productive marine food webs that support our most productive fisheries. On global scales, diatoms help regulate past and current fluxes of CO2 into the ocean.  In the vast, low nutrient regions of the open ocean, marine food webs are dependent on the productivity of tiny cyanobacteria.  I will describe how we use genomic approaches in both laboratory and field studies to identify how phytoplankton interact with their environment and other microbes to adapt to changing ocean conditions.  We scale up these studies through use of our continuous flow cytometer, SeaFlow, which taps into a ship’s seawater intake system and provides a continuous map of abundance, size, and type of the smallest phytoplankton. We use this data to estimate how quickly cells grow and die across thousands of kilometers of ocean basins.  Our ultimate goal is to understand how microbial communities will respond to and will help shape future ocean conditions.