Scales of spatial variability in Lake Michigan glider-based limnological observations

Abstract

This study quantified spatial variability in temperature, colored dissolved organic matter, and chlorophyll-α fluorescence in the epilimnion and hypolimnion of southern Lake Michigan using observations collected by an autonomous underwater vehicle (glider) deployed multiple times per year during 2012–2019. We also include similar analyses of the deep chlorophyll maximum during the summer of those years. Ranges based on semivariance analysis and decorrelation distances generally were 5–15 km, with greater differences observed among seasons in the epilimnion and less unresolved error found for the temperature calculations. Our analysis provides information on submesoscale variation in limnological conditions that may be useful for several applications, including planning field sampling, observation networks, and data assimilation.