Estuarine Ecosystem Response Captured Using a Synoptic Climatology

Estuarine and coastal ecosystems respond strongly to proximate climate forcing. In this study, we present a regional, synoptic climatology as an approach to classify weather patterns that generate interannual variability in coastal and estuarine ecosystems. Synoptic climatology is a method that classifies sea level pressure data into distinct patterns representing common weather features for a specified region. A synoptic climatology was developed for the eastern United States and used to quantify surface conditions affecting Chesapeake Bay during wet and dry years. In a synthesis analysis, several mechanisms were identified that explained the link between weather patterns and ecosystem structure, principal among them is the delivery of freshwater to the Bay during spring. Wet and dry years were characterized by shifts in biogeography of the Chesapeake Bay. The shifts resulted from habitat changes and trophic interactions and included the timing and magnitude of the spring phytoplankton bloom, the distribution/abundance of mesozooplankton and gelatinous zooplankton, and juvenile indices of fish. Synoptic climatology resolved regional weather variability at a spatial scale not strongly controlled by larger-scale climate indices and explained ecosystem responses in Chesapeake Bay.