Physical Processes: What have we learned about Florida Bay in the past five years, and how is that useful to CERP planning and SFER management?

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1 Physical Processes: What have we learned about Florida Bay in the past five years, and how is that useful to CERP planning and SFER management? Peter B. Ortner, UM/RSMAS/CIMAS

2 Modeling Progress Statistical - Paleoecological Hydrodynamic Hydrological Observational Progress Basin Scale Bay Scale Regional Scale The Climate Change Wildcard

3 ENP Marine Monitoring Network Stations 31 Multivariate Linear Regression salinity models have been developed 3 paleo studies linked with statistical models BUOY KEY WHIPRAY BASIN BOB ALLEN

4 Example: Paleosalinity Regime Whipray Basin -Polyhaline

5 Model Output: Mean Stage Paleo vs Observed Stage Station Source N Mean (m) P33 observed paleo:observed Whipray Basin paleo Buoy Key paleo CP observed Whipay Basin paleo Buoy Key paleo

6 Model Output: Mean Flow Paleo vs Observed Flow Station Source N Mean Flow (m 3 /sec) Shark River Slough Taylor Slough Bridge observed Whipray Basin paleo paleo: observed Buoy Key paleo observed Whipray Basin paleo Buoy Key paleo

7 SUMMARY COMPARION Present to Paleo Pre-drainage salinity regime requires about times more freshwater than the current flow regime. Average Everglades stage is now about m lower than pre-drainage. Taylor Slough flow deficit is now >>> than the deficit in Shark River Slough during the dry season. Florida Bay pre-drainage salinity was oligohaline to polyhaline (now psu higher)

8 Numerical Model Domains See Kourafalou et al.

9 Mooring A near top Mooring B near bottom WIND

10 Salinity Intrusion Inter-comparison

11 Hydrological See Swain et al.

12 Basin Scale Observations See Lee et al. presentation

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15 Annual Mean Volume Transports (m3/s) in Florida Bay and Keys (blue arrows) and Estimated Mean Flow Pathways (red arrows). River Discharge shown by (black arrows). Estimated Bank Flow (pink arrows). 15 Shark Trout Other Rivers Taylor McCormick

16 Water renewal and residence times in Florida Bay interior basins are controlled by local wind forcing. Wind forcing results in basin through-flows with net flows through channels balancing net flows over banks. Basin flushing times for complete water renewal are estimated at 1 year for the north-central and northeast subregions and months for western basins. Seasonal water balance estimates indicate that ground water inflow to Florida Bay is negligible. Hypersalinity development in north-central Florida Bay results from the lack of fresh water inputs during the dry season coupled with poor water exchange and shallow depths. At present Everglades discharge to Florida Bay is mostly trapped in the northeast subregion with little influence on hypersalinity development. Hypersalinity development could be regulated by redirection of a portion of Everglades flow to Whipray Basin via McCormick Creek during the dry season. Mean flow patterns within Florida Bay indicate a significant clockwise ckwise circulation of m 3 /s of coastal water that enters through Flamingo Channel in the NW and exits through Rabbit and Twin Key basins with a weak branch moving southward through north-central waters. Everglades discharge in the northeast region is channeled southward by shallow banks into the e southeast subregion and subsequent exchange with Atlantic coastal waters.

17 Jan-98 Jul-98 Jan-99 Jul-99 Jan-00 Jul-00 Jan-01 Jul-01 Jan-02 Jul-02 Jan-03 Jul-03 Jan-04 Jul-04 Jan Bay-wide Observations Hurricane Irene El Niño Date Salinity

18 Mean Mean Spatial Spatial Salinity Salinity Distributions Distributions

19 Hypersalinity Rainfall + Runoff (cm) Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Strong hypersalinity events are the result of a delayed onset in the rainy season

20 Observations Regional Scale

21 See Johns et al.

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23 Key West Sea Level Americas Longest Record Station RSL Uncertainty Cedar Key 19 cm/century ± 1 cm Fernandina Beach 22 cm/century ± 1 cm Key West 22 cm/century ± 4 cm Mayport 24 cm/century ± 2 cm Miami Beach 24 cm/century ± 2 cm Pensacola 22 cm/century ± 2 cm St. Petersburg 25 cm/century ± 2 cm No discernible acceleration in Key West sea level since 1846 Key West (1850) and Today

24 Projected effect of a onemeter sea level rise on Florida At the current rate of Florida sea level rise this will take >400 years.

25 Future Global Sea Level IPCC Projections GCM Model Complexity

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27 QUESTIONS??