Meadows play a critical role in creating a resilient forest ecosystem, acting as ‘islands’ rich in diversity and rare species that are scattered throughout the forest. Meadows are important for wildlife, providing resources for food gathering, nesting and courtship displays. Wet meadows also provide important ecosystem services including filtering sediment, mitigating extreme flood events and helping to recharge groundwater.

The occurrence and persistence of meadows is dependent, in whole or in part, on the hydrology that supports the soil and vegetation characteristics that define them. For example, in certain areas, the saturation of the soil prevents trees from spreading into and overtaking wet meadows. Changes in the water composition of the soil could lead to opportunities for tree establishment, potentially threatening the very existence of particular meadows.

Research shows that climate change in the Pacific Northwest is expected to lead to changes in water resources. However, we know relatively little about how these changes will impact meadows in the region, their functioning and the values they can support in the future. This lack of knowledge is partly due to lack of comprehensive data on Pacific Northwest meadows.

We assessed observed trends in meadows over the last three decades, and, based on our findings, made projections of future trends for meadows under climate change. We used archival satellite data provided by the United States Geological Survey to create a time series illustrating seasonal and long-term changes for individual meadows. We used this dataset to understand historical changes such as tree encroachment and changes in meadow greenness, and to make meadow-specific projections under climate change.

Photo credit: September Autumnleaf