The study relies heavily on a lake-climate model ensemble and observational data from a limited number of lakes, which may not fully represent the diversity of lake ecosystems across the Northern Hemisphere. The lack of data from many regions could potentially limit the generalizability of the findings.

The study does not account for factors other than climate that could influence stratification phenology, such as water transparency, changes in salinity, water residence time, changes in nutrient loading, or differences in lake morphometry. Not accounting for these potentially significant influences makes it difficult to isolate the specific impact of climate change. The lack of data for these variables in the context of the large-scale study is understandable, however their importance is acknowledged in the Discussion, which shows that the authors are aware of the potential shortcoming.

The use of surface temperatures as a proxy for stratification phenology in some instances may not fully capture the complex dynamics of thermal stratification. This simplification could lead to some degree of inaccuracy in the estimated stratification dates, specifically for shallower lakes and those with internal mixing processes.