Effect of dissolved iron on CDOM and other optical properties for dissolved organic matter in lakes and rivers of the Upper Great Lakes states

Three data files are included. The first contains the 2014-2016 field and lab data for 450 sets of measurements on 280 lakes across the NLF, NCHF and NMW ecoregions in Minnesota, Wisconsin, and Michigan. In addition to site names, location information (latitude/longitude), ecoregion, and sampling date, the file contains data on Secchi depth, CDOM measured as a(440), DOC, dissolved iron, chlorophyll-a, specific UV absorbance at 254 nm, SUVA(254), and spectral slopes. The second contains data on concentrations of total, dissolved and particulate iron fractions in 2018 samples from 19 high-CDOM sites (lakes and rivers) in the NLF ecoregion of northern Minnesota plus vertical profile information on a(440), dissolved iron, light penetration, and basic limnological parameters in three NLF lakes with widely varying a(440) levels. The third file contains a(440) and dissolved iron concentrations for six lakes from a laboratory experiment in which known amounts of dissolved iron were added to water samples from six water bodies with a wide range of a(440) levels plus additional spectral absorbance information from the samples.