While climate change is rapidly warming lakes and reservoirs, warming rates can be highly variable among systems because lake characteristics can modulate atmospheric forcing. While it is known that water clarity changes can alter lake water temperatures, it is unknown if frequently observed water clarity trends are sufficient to meaningfully impact the thermal trajectories of diverse lake populations. Using process-based modeling and empirical observations, this study demonstrates that water clarity changes of about 1% per year amplifies or suppresses warming at rates comparable to climate-induced warming. These results demonstrate that trends in water clarity, which are occurring in many lakes, may be as important...