Water transparency in the Laurentian Great Lakes

The Laurentian Great Lakes in the mid-east region of North America, is one of the largest freshwater ecosystems in the world. This data set contains limnological data, focusing on underwater transparency in this ecosystem and the surrounding region, beginning in 1999. Current water transparency data sets highlight the increase in offshore transparency measured by a deepening of average Secchi Disk depth since the invasion of the Dreissenid mussels. However, limited data exists on the Great Lakes to provide insight to the underwater optical environment of the offshore, nearshore, and surrounding water bodies of these lakes. These data illustrate the vertical underwater light environment with data from wavelengths of sunlight including photosynthetically active radiation (400 – 700 nm), UV-A radiation (320 - 400 nm) and UV-B radiation (290 - 320 nm). Understanding the depths to which these specific wavelengths of sunlight reach within a lake, as well as the substances within the lake that may influence the attenuation of sunlight can provide a picture of how habitats within the lake system have been impacted. This data set is a part of a continuous data collaboration among multiple research groups, and will be updated periodically as more data are made available. As such, this initial data set provides a snapshot of water transparency in the Great Lakes, and more sampling sites and years of data are forthcoming.
The data here are contained in four files, including Data_GreatLakes.csv, SiteInformation_GreatLakes.csv, Methods_GreatLakes.csv, and Project_GreatLakes. The main data are in Data_GreatLakes.csv. SiteInformation_GreatLakes.csv, Methods_GreatLakes.csv, and Project_GreatLakes.csv support the main data file with descriptions of the sampling sites, methods by which samples were processed, and project and contact information for each data point, respectively.