Shifting Patterns of Summer Lake Color Phenology in Over 26,000 US Lakes

Area of Science:

• Limnology
• Remote Sensing
• Ecology

Background:

• Lake phenology, the timing of seasonal cycles, is changing due to human activities.
• Long-term data for few lakes limits understanding of landscape-scale phenological shifts.
• Macroscale patterns of lake phenology shifts remain largely unknown.

Purpose of the Study:

• To analyze U.S. summer lake color phenology from 1984-2020 using remote sensing.
• To identify distinct lake phenology groups and their prevalence.
• To investigate factors influencing lake phenology stability.

Main Methods:

• Utilized the LimnoSat-US remote sensing dataset covering over 26,000 lakes.
• Analyzed summer lake color phenology patterns between 1984 and 2020.
• Correlated phenological shifts with lake and landscape characteristics.

Main Results:

• Identified five distinct summer lake color phenology groups mirroring phytoplankton succession.
• Found that lake phenology group transitions are linked to lake inflows, surface area stability, climate variability, and catchment population density.
• Lakes with high inflows and stable surface areas were more stable.
• Lakes in areas with high climate and population variability showed less stability.

Conclusions:

• Summer lake color seasonality exhibits generalizable patterns across the U.S.
• Lake and landscape characteristics significantly influence the stability of lake phenology.
• The LimnoSat-US dataset provides a powerful tool for studying national-scale lake ecosystem changes.