OES Spring Seminar - Marjy Friedrichs

For more than 40 years, the series has fostered connection among current and future professionals. Seminars are held most Thursdays at 3 p.m. during the fall and spring semesters. For information, email Margie Mulholland at mmulholl@odu.edu.

Biography

Dr. Marjy Friedrichs is a research professor at the Virginia Institute of Marine Science (VIMS) at William & Mary. She received her undergraduate degree in Physics from Middlebury College, a Masters in Oceanography from the MIT/Woods Hole Joint program, and a Ph.D. in Oceanography from Old Dominion University. She uses interdisciplinary mathematical models together with monitoring data to better understand how human impacts, such as changes in global climate, urbanization and land use affect coastal water quality. Many of Dr. Friedrichs current modeling projects involve studying long term historical and future changes in hypoxia and coastal acidification in the Chesapeake Bay. She has also led the development of a forecasting system that produces short-term forecasts of hypoxia and acidification metrics for the Bay, and an annual hypoxia report card to track progress towards attaining water quality standards. Through her ongoing collaborative work with Chesapeake Bay Program managers as well as fisheries and aquaculture industry members, she continues to work to make her science relevant for Chesapeake Bay stakeholders.

Abstract

Predicting future Chesapeake Bay hypoxia: implications for management

Hypoxia is an increasingly critical stressor for living resources in the Chesapeake Bay, not only because of excess nutrient inputs derived from agriculture, sewage, and storm water runoff, but also because of predicted increases in atmospheric temperatures and changes in precipitation patterns. Together, the combined effects of anthropogenic nutrient inputs and climate change are leading to one of society's major environmental challenges. To address this problem, we are working to develop and operationalize water quality assessment and projection tools that can account for both climate and nutrient impacts. Specifically, we use hindcasts and forecasts derived from a coupled 3D hydrodynamic-biogeochemical model linked to a Chesapeake Bay watershed model to quantify the impacts of changes in climate and anthropogenic nutrient inputs on the spatial and temporal extent of hypoxia in the Chesapeake Bay. The modeling system has been evaluated using decades of NOAA and EPA monitoring observations collected throughout the Bay. Multiple model scenarios reveal warming in the Chesapeake Bay region is exacerbating hypoxia and has already offset up to a third of the improvements that would otherwise have resulted from past nitrogen reductions. Although our results reassure policymakers and stakeholders that their efforts to reduce hypoxia have been worthwhile, they also indicate that greater reductions will be needed to counteract the ever-increasing impacts of climate change.