Ponds and lakes in the Upper Midwestern region of the United States are significant natural sources of greenhouse gasses (CO2, CH4, and N2O) to the atmosphere. Freshwaters receive a large amount of both inorganic and organic carbon from terrestrial systems, around 3-5 Pg per year with only about 1 Pg actually being transported to the sea. The remainder is either lost to the atmosphere as CO2 or CH4 or buried in sediments. We measured CH4 and CO2 concentrations in the water column and emissions from the water surface seasonally across eight lakes in Minnesota, four in Itasca State Park (IBSL) and four in the Minneapolis-St. Paul Metropolitan area (MSP). The lakes measured varied in how often they experienced lake turnover (mixing regime). Previous work in our lab shows that a lake’s mixing regime plays an important role in the release of CO2 and CH4. Stronger stratification was shown to lead to more CH4 released relative to CO2 released. In addition to gas measurements, profiles were taken to assess environmental parameters of interest to better contextualize each system. Nutrient analyses were done to assess how productive systems were (total phosphorus), measure quantities of carbon entering the system (DOC), and to assess quantities of potential oxidants in each lake in addition to oxygen (Total Fe, NO3-, SO42-). Preliminary results indicate that meromictic lakes contain as much as an order of magnitude more CH4 at depth compared to lakes that mix more frequently.