Update 08/09/2016: The buoys have drifted ashore and are being collected! The map below shows their full journey.
Original post 07/13/2016:
Last week, GLERL scientists released two mobile buoys with GPS tracking capabilities, known as ‘Lagrangian drifters’, into Lake Erie. We are now watching the buoys move around the lake with interest, and not just because it’s fun. The drifters help us test the accuracy of our Lake Erie hydrodynamics model, known as the Lake Erie Operational Forecasting System (LEOFS).LEOFS is driven by meteorological data from a network of buoys, airports, coastal land stations, and weather forecasts which provide air temperatures, dew points, winds, and cloud cover. The mathematical model then predicts water levels, temperatures, and currents (see below).
We use these modeled currents to predict the path that something like, say, an algae bloom would take around the lake. In fact, this is the basis of our HAB tracker tool.
The strength of LEOFS is in how well the modeled currents match reality. While there are a number of stationary buoys in Lake Erie, none provide realtime current measurements. The drifters allow us to see how close we are getting to predicting the actual path an object would take.
Researchers will compare the actual paths of the drifters to the paths predicted by our model. This is a process known pretty universally as ‘in-situ validation’ (in-situ means “in place”). Comparing our models to reality helps us to continually improve them.
For more information and forecasts, see our Great Lakes Coastal Forecasting homepage.
For an up-to-date kmz file of the drifters (that opens as an animation in Google Earth), click here.