The widely accepted belief has been that rising temperatures directly lead to increased algal blooms. However, MSU’s research, which spans 34 years of satellite data, reveals a more nuanced reality. Climate change only directly influenced algal biomass in about one-third of the studied lakes. Of those, just 4% exhibited sustained increases in productivity, while 71% saw only temporary shifts.
Professor Patricia Soranno, co-lead author from MSU’s College of Natural Science, highlights that these findings underscore the unpredictability of climate-driven algal changes. Effective lake management strategies must account for regional and local variables rather than assume uniform responses.
To overcome limitations in historical lake data, MSU researchers developed approached the problem using publicly available satellite imagery and machine learning techniques. This allowed them to compile an extensive dataset covering nearly 24,500 lakes, integrating it with LAGOS-US, a geospatial research platform that describes lake characteristics across the country.
This data-driven methodology provides unprecedented insights into long-term algal trends, helping resource managers better predict and mitigate climate-related impacts on freshwater systems.
An unexpected finding from the study suggests that lakes with heavy human influence—such as those receiving high nutrient inputs from agriculture—show weaker links between climate and algal patterns. In contrast to pristine lakes, which often experience abrupt ecological changes in response to climate shifts, heavily impacted lakes tend to display gradual trends or no clear pattern.
Lakes with moderate human activity, however, were more responsive to climate factors. Those in high-altitude, low-disturbance environments exhibited the strongest and most predictable climate-driven changes. This suggests that human impacts on nutrient levels may, in some cases, mask or override climate signals. However, researchers caution that as climate change accelerates, these lakes may eventually exhibit more pronounced responses, particularly if warming is accompanied by shifts in precipitation patterns.
The study identifies five distinct ways that lakes respond to climate, providing valuable insights for policymakers and water resource managers. These categories include:
Kendra Spence Cheruvelil, dean of MSU’s Lyman Briggs College and study co-author, stresses the importance of integrating both climate and human impact considerations into lake management strategies. Understanding these complex interactions provides a critical foundation for developing policies that safeguard freshwater resources.
This research highlights the value of combining long-term ecological data with advanced analytical techniques to assess climate impacts on a continental scale. The framework established by MSU’s team offers a model that can be applied beyond lakes, helping scientists and decision-makers anticipate how other ecosystems may respond to a changing climate.
