Gas and Energy Fluxes over the Western Basin of Lake Erie

Ecosystem properties, changes, and functions of the Great Lakes (GL) are poorly understood due to the large number of confounding driving forces. We have assembled and implemented a real-time collaborative environmental sensor network to measure the exchange of CO2, H2O, CH4, and energy between the lake surface and the atmosphere in the West Basin of Lake Erie for understanding ecosystem and climate changes. This sensor network establishes the essential infrastructure such as eddy-covariance flux towers along with a mobile unit as well as the key ancillary ecosystem parameters (e.g., microclimate and water properties) to conduct mechanistic explorations of Lake Erie. This sensor network will join our other existing and to-be-constructed flux towers on adjacent land and wetland sites to form an array, thus scaling up the flux measurements at broader spatial scales. Two permanent flux stations (Perm 1 and Perm 2) were installed with Perm 1 near the shoreline and Perm 2 in the open water. Both stations have been functioning since September 1, 2011. The vehicle-based station was applied in five field expeditions. The fluxes of CO2, H2O, and sensible heat at the two permanent stations are within the reasonable ranges while the magnitudes of all three fluxes appeared different between the two stations, with much higher pronounced daily and seasonal changes at Perm 1. The Basin appeared to be a carbon source, varying from ~0.02 mg m-2 s-1 in winter months to >0.16 mg m-2 s-1in the summer at Perm 1. The magnitude at the open water station, meanwhile, remained <0.9 mg m-2 s-1 throughout the year. The data from our mobile flux stations further support that significant spatial variation on the fluxes existed across the Basin. Linking fluxes with other ecosystem and physical properties (algal bloom, wind speed, surface temperature, and sedimentation) is a must to explain the changes in gas fluxes for the lake. This presentation will include the data until mid-December, 2012 on water, energy, and biophysical conditions across the entire Basin. The data is collected in real time and is openly posted for sharing with the scientific community via our project Webpage at: http://research.eeescience.utoledo.edu/lees/LESensorN/index.html.