2020 Neuse Estuary hypoxia forecast

As part of a Sea Grant funded project, we are forecasting moderately low mean oxygen levels for the Neuse Estuary this summer (July-August).  The forecast is based on moderate estuary flushing over the winter and early spring, and moderate streamflow conditions (and nutrient load) in May.  Forecasted oxygen levels are conducive to fish kills, though meteorological variability make such events difficult to predict in advance.  The following Sea Grant post shows the 2020 forecast as well as a retrospective assessment of least year’s forecast.

Midsummer Neuse River Forecast Shows Greater Potential for Fish Kills

 

2020 Gulf hypoxia expected to be severe, but not a record year

Researchers are expecting severe hypoxia this summer in the Northern Gulf of Mexico.  A NOAA-sponsored ensemble of models has forecasted a ‘Dead Zone’ of 6700 sq mi, substantially larger than the state of Connecticut. The best estimate from the NCSU/Obenour Lab model, which is included in the NOAA ensemble, is 17,200 sq km (6600 sq mi). This estimate reflects above-average flow and nutrient loading from the Mississippi River this spring (as determined by USGS), coupled with average westward wind velocities that deliver nutrients and freshwater over the Louisiana-Texas shelf.

Model forecasts are compared to observations from the midsummer LUMCON shelfwide cruise. Considering typical weather variability and other system uncertainties, we estimate less than a 5% chance of observing a record (>22,700 sq km) hypoxic area this year. There is almost no chance of observing a hypoxic area of less than 5000 sq km (management goal), unless a major storm disrupts the hypoxic zone prior to the monitoring cruise.

2019 Neuse Estuary hypoxia forecast

As part of a Sea Grant funded project, we are forecasting higher mean oxygen levels for the Neuse Estuary this summer (July-August).  The forecast is based on high estuary flushing over the winter and early spring, followed by a drop in flow (and nutrient load) in May.  Higher average oxygen levels can reduce the risk of severe fish kills, though meteorological variability make such events difficult to predict in advance.

For more information…

Researchers Forecast Healthier Neuse River Oxygen Levels

2019 Could be a record year for Gulf hypoxia

Researchers are expecting severe hypoxia this summer in the Northern Gulf of Mexico.  A NOAA-sponsored ensemble of models has forecasted a ‘Dead Zone’ of 20,300 sq km, roughly equivalent to the land area of Massachusetts. The best estimate from the NCSU/Obenour Lab model is 20,800 sq km. This estimate reflects the above average flow and nutrient loading from the Mississippi River this spring, coupled with strong westward winds to deliver nutrients and freshwater over the Louisiana-Texas shelf.

Considering the uncertainty in these predictions, largely attributable to summer hydro-meteorological variability, there is a 22% chance that a record hypoxic zone could be measured by the LUMCON shelfwide cruise this summer.