Notes
Slide Show
Outline
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Florida Bay Innerbasin Study
  • Transport and Exchange
  •  of Florida Bay Interior Waters
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Florida Bay & Everglades National Park
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The Problem
  • Florida Bay is located downstream of the Everglades discharge that has been altered over the past century due to South Florida land use practices.
  • The salinity of Florida Bay has undergone dramatic changes.
  • Salinity values reached their most extreme, up to 70, in the late 1980s, concurrent with ecological changes in Florida Bay including degradation of water quality and a mass sea-grass die-off.
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Question
  • How and at what rate do storms, changing fresh water flows, sea level rise and local evaporation-precipitation patterns influence circulation and salinity patterns within Florida Bay and exchanges between the bay and adjacent waters ?
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Proposed Research Objectives
  • Multi-institutional study to resolve the volume and salt transports in Florida Bay.
  • Compute volume transport, salt balances and resident times in the Bay.
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Florida Bay
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Florida Bay Regions
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Florida Bay Bathymetry
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Florida Bay Banks
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Fresh Water Inputs
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Daily average fresh water discharge to Florida Bay for 2001.
Data provided by U.S. Geological Survey, South Florida Ecosystem Program, Information Access Site (USGS, 2005).
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Monthly average fresh water fluxes to Fla. Bay from long-term (25 years) measurements. (Nuttle et al., 2000).
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 Seasonal cycle of monthly average salinity
for the four regions of Florida Bay
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Moored instrumentation sites from recent studies of the inner basin circulation and exchange processes in northeast, north-central, and western basin sub-regions of Florida Bay. Also shown are USGS transport and river discharge measurement stations.
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The Boat R/V Virginia K
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Instruments (The Boat)
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Instruments (The Moorings)
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Instruments (The Drifters)
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Central Basin
Florida Bay
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Location of Central Basin Measurement Stations
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Central Basin Surface Salinity
from high-resolution surveys of the R/V Virginia K using continuous underway measurement for:
A) Mar. 28 dry season;
B) Jul. 16 near the end of the dry season;
C) Sept. 16 wet season; and D) Oct. 28 near the end of wet season 2001.
Vessel track shown with dotted line.
Surface drifter trajectories shown with red arrows.
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Time series of the Central Basin average salinity during dry and wet seasons of 2001
from R/V Virginia K spatial surveys.
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Location of ENP marine monitoring stations in Florida Bay (triangles), CMAN/SeaKeys wind stations (squares), and the location of fresh water discharge points (arrows) superimposed on the bays bank/basin configuration (yellow/white) and mangrove islands (green).
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Florida Bay
Hypersalinity Event
(2001)
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Linear regression of along-channel currents against volume transport measured with shipboard ADCP transects across the current meter sites at Topsy (top) and Twisty (bottom) transects during the wet season of 2001.
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Channel Volume Transports

Wet Season

3 hour low-pass filtered volume transports derived for the major flow channels to the Central Basin for a one month period from the 2.5 month total record of the wet season 2001.
Positive values are inflows and negative are outflows. Also shown are east-west and north-south wind components from the NWFB SeaKeys site.
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40 hour low-pass filtered NWFB wind components and volume transports through CB flow channels during wet season 2001. Positive values are inflows and negative are outflows.
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Linear regression between subtidal time series of east-west wind and transports through Central Basin flow channels during the wet season 2001.
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Florida Bay Sea Level Anomaly Movie
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Subtidal sea level time series from selected stations of the ENP monitoring array and winds for the NWFB SeaKeys station, rotated 50º into along-bay axis and cross-bay axis components (along-axis winds + toward 50º and cross-axis winds + toward 140º. Sea level stations were selected to provide coverage of the entire bay.
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Sea Level Anomaly Movie
Hurricane Gabrielle (2001)
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Gridded and Contoured Sea Level Fields

Derived from the ENP monitoring array for fall 2001 wind events.

Winds from the NWFB SeaKeys station are shown with black arrows.
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Subtidal time series of the Total Volume Transport (QT)

 into (+) and out of (-) Central Basin derived from gridded sea level fields,

shown with east-west (U) and north-south (V) winds

for dry (a) and wet (b) seasons of 2001.
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Wet season 2001 subtidal time series of the:
Total channel flow (Qc) and Total bank flow (Qb) (top panel);

Total bank flow plotted with along-axis winds (middle panel); and

Total channel flow plotted with winds rotated 80deg (bottom panel).
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Seasonal and annual means of Total Transport (QT) from Central Basin sea level monitoring data, total measured channel transport (Qc) and residual bank transport (Qb) from Qb = QT - Qc in m3/s for 2001.

[Mean volume of Central Basin is 56.55 x 106 (m3).]
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NE Basin
Florida Bay
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Location of NE Basin Measurement Stations
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Drifters Deployment
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Salinity Surveys  (NE Basin & Florida Bay 2002 -2003)
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Salinity and Fresh Water Discharge
(NE Basin 2002 - 2003)
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Channels Transport and Wind
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Seasonal and annual means of Total Transport (QT)
from NE Basin volume anomalies data,
total measured channel transport (Qc)
and residual bank transport (Qb) from
Qb = QT - Qc in m3/s

for 2002.
[Mean volume of NE Basin is 4.41 x 108 (m3).]
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West Basin Florida Bay
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West Basin Florida Bay Mooring Array
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Virginia K W Basin and Monthly Survey
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Salinity Surveys
(W Basin - Fl. Bay)
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Salinity Survey (W Basin & Florida Bay)
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Salinity Surveys       (W Basin)
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Drifter Deployments
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Drifter Deployments
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Drifter Deployments
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Drifter Deployments
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Drifter Deployments
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Moorings
Wet Season
Jun Dec 2004
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Hurricanes Frances & Ivan
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Salinity Time Series
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Moorings
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Moorings Current - Transport
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Moorings Transport
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Moorings
Dry Season
Dec 2004 – Jun 2005
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Salinity Time Series
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Moorings Current
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Moorings   Current - Transport
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Moorings Transport
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Conclusions
  • In the Central Basin 2001:
  • Dry Season - eastward winds produce mean through-flow of 11 m3/s and basin renewal times of 2-3 mo.


  • Wet Season – westward winds cause mean through-flow of 3 m3/s and basin renewal times of 6-7 mo.


  • Flushing time for complete water renewal ~= 6-12 mo.


  • In the NE Basin 2002-2003:
  • Dry Season - eastward winds produce mean through-flow of 31 m3/s and basin renewal times of 5.5 mo.


  • Wet Season – westward winds cause mean through-flow of 13 m3/s and basin renewal times of 12 mo.


  • Flushing time for complete water renewal ~= 6-12 mo.
  • ************************************************************************************************************
  • Water renewal and residence times in Florida Bay are primarily controlled by local wind forcing.


  • Hypersalinity development in north-central Florida Bay results from reduced fresh water inputs during the dry season coupled with poor exchange with surrounding regions.


  • Hypersalinity development  in Fl. Bay could be regulated by redirection of a portion of Everglades flow to Whipray Basin via McCormick Creek during the dry season.
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Publications
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For the Future ?
  • Florida Bay Transport and Salinity Patterns
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