Two decades of cyanobacterial bloom dynamics in the Great Lakes: insights from multi-mission ocean color sensors
Two decades of cyanobacterial bloom dynamics in the Great Lakes: insights from multi-mission ocean color sensors
Sachidananda Mishra, Richard Stumpf, Timothy Wynne, Alexandria G. Hounshell
Sachidananda Mishra, Richard Stumpf, Timothy Wynne, Alexandria G. Hounshell
The Question: How do we maintain a continuous data record of cyanobacteria observations when sensors change and there are mission gaps?
The Question: How do we maintain a continuous data record of cyanobacteria observations when sensors change and there are mission gaps?
Our Solution:
Our Solution:
To bridge the observation gap between MERIS and OLCI, we used CyanNet, a science-informed deep learning framework, to derive the Cyanobacteria Index (CIcyano) from MODIS-Terra and harmonize it with existing products, creating a seamless 25-year time series (2000–2024).
Key Findings from the Multi-Decadal Dataset:
Key Findings from the Multi-Decadal Dataset:
Our analysis reveals complex, spatially variable changes across the Great Lakes:
Western Lake Erie: Shows a statistically significant increasing trend in both bloom intensity and extent since 2000, despite high inter-annual variability.
Sandusky & Saginaw Bays: Interestingly, these regions exhibit slight decreasing trends in bloom severity.
Green Bay & Lake Winnebago: Observations show negligible changes over the 25 years.