Lakes serve as effective sentinels of climate change due to their sensitivity to climate, rapid response to changes, and ability to integrate information about changes in the surrounding landscape. The study identifies key response variables that reflect the effects of climate change on lakes and their catchments, including water temperature, water level, ice phenology, and chemical variables such as dissolved organic carbon (DOC) and oxygen concentrations. These variables are influenced by a range of physical, chemical, and biological responses to climate. However, the effectiveness of these indicators varies depending on regional climate, catchment characteristics, and lake mixing regimes. Confounding factors such as eutrophication, acidification, and land-use changes can complicate the interpretation of climate signals, but analytical tools like detrending and filtering can help address these issues. Lakes are particularly useful for detecting climate change because they respond rapidly to climate-related changes and integrate information about changes in the catchment. However, the large range in lake morphology, catchment characteristics, and geographic locations means that broad statements about their ability to capture climate change effects must be cautious. The study highlights the importance of identifying appropriate indicators for different lake types and regions, and the challenges of extracting climate signals from confounding factors. The use of lakes as sentinels is further complicated by interactions with other environmental changes, such as eutrophication and acidification. Despite these challenges, lakes provide valuable insights into climate change effects on ecosystems, particularly in detecting changes in water temperature, ice phenology, and nutrient concentrations. The study also emphasizes the importance of considering geographic variation in the use of lakes as sentinels, as climate-driven changes can have different effects depending on location, elevation, and other factors. Overall, the study concludes that lakes have strong potential as sentinels of current climate change and can contribute to our understanding of global climate effects.Lakes serve as effective sentinels of climate change due to their sensitivity to climate, rapid response to changes, and ability to integrate information about changes in the surrounding landscape. The study identifies key response variables that reflect the effects of climate change on lakes and their catchments, including water temperature, water level, ice phenology, and chemical variables such as dissolved organic carbon (DOC) and oxygen concentrations. These variables are influenced by a range of physical, chemical, and biological responses to climate. However, the effectiveness of these indicators varies depending on regional climate, catchment characteristics, and lake mixing regimes. Confounding factors such as eutrophication, acidification, and land-use changes can complicate the interpretation of climate signals, but analytical tools like detrending and filtering can help address these issues. Lakes are particularly useful for detecting climate change because they respond rapidly to climate-related changes and integrate information about changes in the catchment. However, the large range in lake morphology, catchment characteristics, and geographic locations means that broad statements about their ability to capture climate change effects must be cautious. The study highlights the importance of identifying appropriate indicators for different lake types and regions, and the challenges of extracting climate signals from confounding factors. The use of lakes as sentinels is further complicated by interactions with other environmental changes, such as eutrophication and acidification. Despite these challenges, lakes provide valuable insights into climate change effects on ecosystems, particularly in detecting changes in water temperature, ice phenology, and nutrient concentrations. The study also emphasizes the importance of considering geographic variation in the use of lakes as sentinels, as climate-driven changes can have different effects depending on location, elevation, and other factors. Overall, the study concludes that lakes have strong potential as sentinels of current climate change and can contribute to our understanding of global climate effects.