As predicted by an earlier forecast sponsored by NCCOS, dissolved oxygen conditions in Maryland’s portion of the Chesapeake Bay main channel continued to be average for most of the summer of 2016. In mid-June, NCCOS issued the annual hypoxic zone forecasts for the Chesapeake Bay, predicting a close to average sized hypoxic volume for the bay due to slightly below average spring flows (January-May) and nitrogen loading from the Susquehanna and Potomac rivers.
The late-August hypoxic (dead zone) water volume (areas below 2 mg/l oxygen) was approximately 0.97 cubic miles, which is close to the late-August long-term average of 0.95 cubic miles reports the Maryland Department of Natural Resources. No anoxic zones (areas below 0.2 mg/l) were detected. The average Chesapeake hypoxic zone size appears to be decreasing.
Each year (June-September), the Maryland Department of Natural Resources computes these low-oxygen volumes from data collected by Maryland and Virginia monitoring teams. ‘While these modeling and forecasting tools that we have developed are critical for management guidance, they also allow us to pursue the outcome of informing stakeholders, politicians, managers and citizens about these damaging ‘dead zones,’ what is causing them, and how we are using state-of-the-art forecasts to guide management efforts to alleviate this stress on vital ecosystems and economic resources,’ said Dr. Rob Magnien, Director of NCCOS’s Center for Sponsored Coastal Ocean Research.
The forecast is based on Susquehanna River nutrient run-off and river data from the U.S. Geological Survey (USGS) and includes a cooperative agreement between USGS and the Maryland Department of Natural Resources. Those nutrient run-off numbers are then inserted into models developed by the University of Maryland Center for Environmental Science and University of Michigan School of Natural Resources and Environment with funding from NCCOS. NCCOS has funded a Chesapeake Bay dissolved oxygen forecast each year since 2007.
For more information, contact Alan.Lewitus@noaa.gov.