Impact of salinization on lake stratification and spring mixing

Anthropogenic freshwater salinization affects thousands of lakes worldwide, and yet little is known about how salt loading may shift timing lake stratification spring mixing in dimictic lakes. Here, we investigate the impact on Lakes Mendota Monona, Wisconsin, by deploying under-ice buoys to record salinity gradients, using an analytical approach quantify thresholds that prevent mixing, running ensemble vertical one-dimensional hydrodynamic models (GLM, GOTM, Simstrat) long-term winter stratification. We found gradients between surface bottom waters persist up a month after ice-off, theory predicts gradient 1.3–1.4 g kg−1 would mixing. Numerical project delays increases water column stability, with ramifications for oxygenation waters, biogeochemistry, habitability.