This project focuses on using long-term dissolved oxygen profiles to identify trends in dissolved oxygen at different depths, for lakes with different watershed features, and in lakes of different trophic status. Additionally, we desire to explore the response of dissolved oxygen concentrations to changing temperatures. We will also look at how temperature and productivity interact to influence dissolved oxygen. Ideally, lakes will have at least 15 years of data including a dissolved oxygen/temperature profile taken annually near the height of thermal stratification. As of fall 2016, the project is "green" and we are collecting data contributions, assembling a list of lakes and collaborators, and establishing a timeline for the project. We anticipate that the project will transition to "yellow" and then "red" in 2017. The Temperature Sentinels Global Project may provide a good starting point if we can get dissolved oxygen profiles from those lakes. Contact one of the project leaders for more information.