Home Introduction >Climate Variability Impacts on Ecosys. Degradation & Restoration in Chesapeake Bay Baseline Variability: Chesapeake Bay Chesapeake Bay WQ & Climate Variability FL Everglades: Hydro. Changes & Degradation Everglades Climate Variability & Relevance Role of Time in Restoration Planning Acknowledgements References Figures

Patterns of ecosystem response to natural climate variability of the late Holocene provides relevant information on the impacts of a range of climate conditions on extant species and communities. The last 2,000 years are particularly suitable to examine short-term climate variability because they encompass a time when orbitally-driven solar insolation forcing of climate, ice sheet, and sea-level are of secondary importance. Rather, climate dynamics of the past two millennia are dominated by interannual and decadal patterns in ENSO (various indices including the Southern Oscillation Index [SOI]), the NAO (Hurrell et al., 2003), (AMO) (Enfield et al., 2001), and the PDO (Barnett et al., 1999), as well as volcanic and solar processes. Late Holocene climate variability influences temperature, precipitation, and atmospheric-oceanic interactions on interannual and decadal time scales to varying degrees in different regions. Interactions among these patterns serve to amplify or dampen climate response in complex, partially understood ways. For example, positive AMO periods are consistently associated with greater than normal drought frequency in the U.S., but the PDO phase during a positive AMO phase influences the location of most severe drought (McCabe et al., 2004). Likewise, NAO variability has a large impact on mid-Atlantic Chesapeake Bay region winter temperature and precipitation, whereas ENSO strongly influences south Florida winter precipitation.

Although the complexities and interactions of these climate drivers are partially understood, the superposition of anthropogenic atmospheric greenhouse forcing on already complex processes makes the study of climate-ecosystem linkages especially difficult (Jones and Mann, 2004). The ecological community has begun to recognize the critical importance of climate variability in driving terrestrial, shallow marine, open ocean, and tropical reef ecosystems. With a greater appreciation for the importance of climate, we briefly discuss reconstructed climate variability in the Chesapeake Bay and south Florida regions and the implications for future ecosystem management.