PUBLICATION SPOTLIGHT

Global dominance of seasonality in shaping lake-surface-extent dynamics

| Li et al., 2025

Humans across the globe rely on lakes for water and other ecosystem services without fully understanding what drives changes in their extents. Li et al., 2025 reveals that seasonality, rather than long-term climate trends, is the dominant driver of lake surface-extent changes worldwide. Using a deep-learning model to fuse MODIS and Landsat satellite data, researchers mapped 1.4 million lakes monthly from 2001-2023, discovering that seasonality-dominated lakes constitute 66% of global lake area and affect regions where over 90% of the world’s population lives. Most significantly, extreme seasonal events can have impacts that exceed 23 years of combined long-term changes and regular seasonal variations. Low-water extremes doubled the contraction of 42% of shrinking lakes and completely offset the long-term expansion in 45% of growing lakes. These findings help clarify global lake dynamics that were previously difficult to study using only Landsat or MODIS data alone because of limitations in temporal and spatial resolution, respectively. Understanding seasonal patterns in lake extent can inform local water resource management, ecosystem protection, and climate modeling. Critically, multisource satellite data fusion can help scientists study dynamics that are impossible to decode with one satellite alone.