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Estuarine Salinity Zones in US East Coast, Gulf of Mexico, and US West Coast from 1999-01-01 to 1999-12-31 (NCEI Accession 0127396)

Published by NOAA National Centers for Environmental Information | National Oceanic and Atmospheric Administration, Department of Commerce | Metadata Last Checked: January 29, 2026 | Last Modified: 2015-04-22T00:00:00.000+00:00
These unprojected (geographic coordinates) 3-Zone Average Annual Salinity Digital Geographies are based on analysis of long-term salinity data for 147 estuaries of the contiguous United States. Each estuary is subdivided into three zones between the head(s) of tide, and the seaward boundaries based on annual-averaged and depth-averaged salinities. The salinities used to define the three zones are: (1) Tidal Fresh Zone (0 to 0.5 parts per thousand); (2) Mixing Zone (0.5 to 25 parts per thousand); (3) Seawater Zone (25 parts per thousand or greater). This 3-zone scheme is considered static rather than dynamic, because it does not take into account the seasonal variations in salinity patterns and stratification that occur in most estuaries. Nonetheless, it provides a simple and readily understandable way to depict the long-term salinity characteristics of U.S. estuarine waters. Note that not all estuaries contain all three zones - for example, Baffin Bay, Texas, receives relatively little annual freshwater inflow, and is considered to be entirely Seawater Zone. This 3-zone scheme was originally presented in the National Estuarine Inventory (NEI) Data Atlas, Vol. I (NOAA/NOS 1985) for 92 estuaries of the contiguous United States. In the 1990s, digital geographies were refined and many estuaries were added to become a key layer within the Coastal Assessment Framework (NOAA 2007). These 3-Zone Average Annual Salinity Digital Geography have been used for applications in natural resource science and management. They provided the spatial framework and basis for development of NOAA's Estuarine Living Marine Resources (ELMR) Program (Nelson and Monaco 2000), and also for NOAA's National Estuarine Eutrophication Assessment (Bricker et al. 2007).

Resources

13 resources available

  • NCEI Dataset Landing Page

    PLACEHOLDER/VALUE
    Download

  • Descriptive Information

    PLACEHOLDER/VALUE
    Download

  • HTTPS

    PLACEHOLDER/VALUE
    Download

  • FTP

    PLACEHOLDER/VALUE
    Download

  • https://doi.org/10.7289/v5445jkv

    PLACEHOLDER/VALUE
    Download

  • https://doi.org/10.7289/v57w698t

    PLACEHOLDER/VALUE
    Download

  • https://doi.org/10.7289/v5pg1ptj

    PLACEHOLDER/VALUE
    Download

  • https://www.ncei.noaa.gov/archive/accession/0163992

    PLACEHOLDER/VALUE
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  • https://www.ncei.noaa.gov/archive/accession/0163993

    PLACEHOLDER/VALUE
    Download

  • https://coastalscience.noaa.gov/project/estuarine-species-database-noaa-estuarine-living-marine-resources-program/

    PLACEHOLDER/VALUE
    Download

  • GCMD Keyword Forum Page

    PLACEHOLDER/VALUE
    Download

  • NCEI Contact Information

    PLACEHOLDER/VALUE
    Download

  • NOAA National Centers for Coastal Ocean Science (NCCOS) website

    PLACEHOLDER/VALUE
    Download

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0127396 ANALYSES - ANNUAL SUMMARIES SALINITY GIS product model output NOAA National Ocean Service Coastal Assessment Framework (CAF) Estuarine Living Marine Resources (ELMR) Gulf of Mexico North Atlantic Ocean North Pacific Ocean oceanography DOC/NOAA/NESDIS/NODC > National Oceanographic Data Center, NESDIS, NOAA, U.S. Department of Commerce DOC/NOAA/NOS > National Ocean Service, NOAA, U.S. Department of Commerce EARTH SCIENCE > OCEANS > SALINITY/DENSITY > SALINITY Environmental Monitoring Tides and Currents estuary salinity zones OCEAN > ATLANTIC OCEAN > NORTH ATLANTIC OCEAN OCEAN > ATLANTIC OCEAN > NORTH ATLANTIC OCEAN > GULF OF AMERICA OCEAN > ATLANTIC OCEAN > NORTH ATLANTIC OCEAN > GULF OF MEXICO OCEAN > PACIFIC OCEAN > NORTH PACIFIC OCEAN Alabama Alamitos Bay Albemarle Sound Alsea River Altamaha River Anaheim Bay Apalachee Bay Apalachicola Bay Aransas Bay Atchafalaya/Vermilion Bays Baffin Bay Barataria Bay Barnegat Bay Biscayne Bay Blue Hill Bay Bogue Sound Boston Harbor Brazos River Breton/Chandeleur Sound Broad River Buzzards Bay Calcasieu Lake California Caloosahatchee River Cape Cod Bay Cape Fear River Casco Bay Central San Francisco/San Pablo/Suisun Bays Charleston Harbor Charlotte Harbor Chesapeake Bay Mainstem Chester River Chincoteague Bay Choctawhatchee Bay Choptank River Coastal Columbia River Connecticut Connecticut River Contiguous Coos Bay Coquille River Corpus Christi Bay Coterminous Damariscotta River Delaware Delaware Bay Delaware Inland Bays District of Columbia Drakes Estero Eastern Bay Eel River Elk/Sassafras Rivers Elkhorn Slough Englishman/Machias Bay Estuaries Florida Florida Bay Galveston Bay Georgia Grays Harbor Great Bay Great South Bay Gulf Coast Gulf of Maine Gulf of Mexico Hampton Harbor Honga River Hood Canal Hudson River/Raritan Bay Humboldt Bay Indian River Ingram/Fleets Bays James River Kennebec/Androscoggin Rivers Klamath River Laguna Madre Lake Borgne Lake Pontchartrain Long Island Sound Louisiana Lynnhaven River Maine Maryland Maryland Inland Bays Massachusetts Massachusetts Bay Matagorda Bay Mermentau River Merrimack River Mid-Atlantic Mission Bay Mississippi Mississippi River Mississippi Sound Mobile Bay Monterey Bay Morro Bay Muscongus Bay Narragansett Bay Narraguagus Bay Nehalem River Netarts Bay Neuse River New England New Hampshire New Jersey New Jersey Inland Bays New River New York Newport Bay North Atlantic North Carolina North/South Santee Rivers Oregon Ossabaw Sound Pacific Pacific Ocean Pamlico Sound Pamlico/Pungo Rivers Passamaquoddy/Cobscook Bays Patapsco/Gunpowder Rivers Patuxent River Peconic/Gardiners Bay Pennsylvania Penobscot Bay Pensacola Bay Perdido Bay Piankatank River/Mobjack Bay Plum Island Sound Poquoson/Back Rivers Port Orchard Sound Potomac River Puget Sound Rappahannock River Rhode Island Rogue River Rookery Bay Sabine Lake Saco Bay San Antonio Bay San Diego Bay San Pedro Bay Santa Monica Bay Sarasota Bay Savannah River Severn River Sheepscot Bay Siletz Bay Siuslaw River Skagit Bay/Whidbey Basin South Atlantic South Carolina South Puget Sound South San Francisco Bay Southeast St. Andrew Bay St. Andrew/St. Simons Sounds St. Catherines/Sapelo Sounds St. Helena Sound St. Johns River St. Marys River/Cumberland Sound Stono/North Edisto Rivers Suwannee River Tampa Bay Tangier/Pocomoke Sound Ten Thousand Islands Terrebone/Timbalier Bays Texas Tijuana Estuary Tillamook Bay Tomales Bay Umpqua River United States Virginia Virginia Eastern Shore Waquoit Bay Washington Wells Bay West Coast Willapa Bay Winyah Bay Yaquina Bay York River 1999 U58WL4

Complete Metadata
@type dcat:Dataset
accessLevel non-public
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                                            {
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describedByType application/octet-steam
description These unprojected (geographic coordinates) 3-Zone Average Annual Salinity Digital Geographies are based on analysis of long-term salinity data for 147 estuaries of the contiguous United States. Each estuary is subdivided into three zones between the head(s) of tide, and the seaward boundaries based on annual-averaged and depth-averaged salinities. The salinities used to define the three zones are: (1) Tidal Fresh Zone (0 to 0.5 parts per thousand); (2) Mixing Zone (0.5 to 25 parts per thousand); (3) Seawater Zone (25 parts per thousand or greater). This 3-zone scheme is considered static rather than dynamic, because it does not take into account the seasonal variations in salinity patterns and stratification that occur in most estuaries. Nonetheless, it provides a simple and readily understandable way to depict the long-term salinity characteristics of U.S. estuarine waters. Note that not all estuaries contain all three zones - for example, Baffin Bay, Texas, receives relatively little annual freshwater inflow, and is considered to be entirely Seawater Zone. This 3-zone scheme was originally presented in the National Estuarine Inventory (NEI) Data Atlas, Vol. I (NOAA/NOS 1985) for 92 estuaries of the contiguous United States. In the 1990s, digital geographies were refined and many estuaries were added to become a key layer within the Coastal Assessment Framework (NOAA 2007). These 3-Zone Average Annual Salinity Digital Geography have been used for applications in natural resource science and management. They provided the spatial framework and basis for development of NOAA's Estuarine Living Marine Resources (ELMR) Program (Nelson and Monaco 2000), and also for NOAA's National Estuarine Eutrophication Assessment (Bricker et al. 2007).
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identifier gov.noaa.nodc:0127396
issued 2015-04-21T00:00:00.000+00:00
keyword 
                                            [
  "0127396",
  "ANALYSES - ANNUAL SUMMARIES",
  "SALINITY",
  "GIS product",
  "model output",
  "NOAA National Ocean Service",
  "Coastal Assessment Framework (CAF)",
  "Estuarine Living Marine Resources (ELMR)",
  "Gulf of Mexico",
  "North Atlantic Ocean",
  "North Pacific Ocean",
  "oceanography",
  "DOC/NOAA/NESDIS/NODC > National Oceanographic Data Center, NESDIS, NOAA, U.S. Department of Commerce",
  "DOC/NOAA/NOS > National Ocean Service, NOAA, U.S. Department of Commerce",
  "EARTH SCIENCE > OCEANS > SALINITY/DENSITY > SALINITY",
  "Environmental Monitoring",
  "Tides and Currents",
  "estuary",
  "salinity",
  "zones",
  "OCEAN > ATLANTIC OCEAN > NORTH ATLANTIC OCEAN",
  "OCEAN > ATLANTIC OCEAN > NORTH ATLANTIC OCEAN > GULF OF AMERICA",
  "OCEAN > ATLANTIC OCEAN > NORTH ATLANTIC OCEAN > GULF OF MEXICO",
  "OCEAN > PACIFIC OCEAN > NORTH PACIFIC OCEAN",
  "Alabama",
  "Alamitos Bay",
  "Albemarle Sound",
  "Alsea River",
  "Altamaha River",
  "Anaheim Bay",
  "Apalachee Bay",
  "Apalachicola Bay",
  "Aransas Bay",
  "Atchafalaya/Vermilion Bays",
  "Baffin Bay",
  "Barataria Bay",
  "Barnegat Bay",
  "Biscayne Bay",
  "Blue Hill Bay",
  "Bogue Sound",
  "Boston Harbor",
  "Brazos River",
  "Breton/Chandeleur Sound",
  "Broad River",
  "Buzzards Bay",
  "Calcasieu Lake",
  "California",
  "Caloosahatchee River",
  "Cape Cod Bay",
  "Cape Fear River",
  "Casco Bay",
  "Central San Francisco/San Pablo/Suisun Bays",
  "Charleston Harbor",
  "Charlotte Harbor",
  "Chesapeake Bay Mainstem",
  "Chester River",
  "Chincoteague Bay",
  "Choctawhatchee Bay",
  "Choptank River",
  "Coastal",
  "Columbia River",
  "Connecticut",
  "Connecticut River",
  "Contiguous",
  "Coos Bay",
  "Coquille River",
  "Corpus Christi Bay",
  "Coterminous",
  "Damariscotta River",
  "Delaware",
  "Delaware Bay",
  "Delaware Inland Bays",
  "District of Columbia",
  "Drakes Estero",
  "Eastern Bay",
  "Eel River",
  "Elk/Sassafras Rivers",
  "Elkhorn Slough",
  "Englishman/Machias Bay",
  "Estuaries",
  "Florida",
  "Florida Bay",
  "Galveston Bay",
  "Georgia",
  "Grays Harbor",
  "Great Bay",
  "Great South Bay",
  "Gulf Coast",
  "Gulf of Maine",
  "Gulf of Mexico",
  "Hampton Harbor",
  "Honga River",
  "Hood Canal",
  "Hudson River/Raritan Bay",
  "Humboldt Bay",
  "Indian River",
  "Ingram/Fleets Bays",
  "James River",
  "Kennebec/Androscoggin Rivers",
  "Klamath River",
  "Laguna Madre",
  "Lake Borgne",
  "Lake Pontchartrain",
  "Long Island Sound",
  "Louisiana",
  "Lynnhaven River",
  "Maine",
  "Maryland",
  "Maryland Inland Bays",
  "Massachusetts",
  "Massachusetts Bay",
  "Matagorda Bay",
  "Mermentau River",
  "Merrimack River",
  "Mid-Atlantic",
  "Mission Bay",
  "Mississippi",
  "Mississippi River",
  "Mississippi Sound",
  "Mobile Bay",
  "Monterey Bay",
  "Morro Bay",
  "Muscongus Bay",
  "Narragansett Bay",
  "Narraguagus Bay",
  "Nehalem River",
  "Netarts Bay",
  "Neuse River",
  "New England",
  "New Hampshire",
  "New Jersey",
  "New Jersey Inland Bays",
  "New River",
  "New York",
  "Newport Bay",
  "North Atlantic",
  "North Carolina",
  "North/South Santee Rivers",
  "Oregon",
  "Ossabaw Sound",
  "Pacific",
  "Pacific Ocean",
  "Pamlico Sound",
  "Pamlico/Pungo Rivers",
  "Passamaquoddy/Cobscook Bays",
  "Patapsco/Gunpowder Rivers",
  "Patuxent River",
  "Peconic/Gardiners Bay",
  "Pennsylvania",
  "Penobscot Bay",
  "Pensacola Bay",
  "Perdido Bay",
  "Piankatank River/Mobjack Bay",
  "Plum Island Sound",
  "Poquoson/Back Rivers",
  "Port Orchard Sound",
  "Potomac River",
  "Puget Sound",
  "Rappahannock River",
  "Rhode Island",
  "Rogue River",
  "Rookery Bay",
  "Sabine Lake",
  "Saco Bay",
  "San Antonio Bay",
  "San Diego Bay",
  "San Pedro Bay",
  "Santa Monica Bay",
  "Sarasota Bay",
  "Savannah River",
  "Severn River",
  "Sheepscot Bay",
  "Siletz Bay",
  "Siuslaw River",
  "Skagit Bay/Whidbey Basin",
  "South Atlantic",
  "South Carolina",
  "South Puget Sound",
  "South San Francisco Bay",
  "Southeast",
  "St. Andrew Bay",
  "St. Andrew/St. Simons Sounds",
  "St. Catherines/Sapelo Sounds",
  "St. Helena Sound",
  "St. Johns River",
  "St. Marys River/Cumberland Sound",
  "Stono/North Edisto Rivers",
  "Suwannee River",
  "Tampa Bay",
  "Tangier/Pocomoke Sound",
  "Ten Thousand Islands",
  "Terrebone/Timbalier Bays",
  "Texas",
  "Tijuana Estuary",
  "Tillamook Bay",
  "Tomales Bay",
  "Umpqua River",
  "United States",
  "Virginia",
  "Virginia Eastern Shore",
  "Waquoit Bay",
  "Washington",
  "Wells Bay",
  "West Coast",
  "Willapa Bay",
  "Winyah Bay",
  "Yaquina Bay",
  "York River",
  "1999",
  "U58WL4"
]
landingPage https://www.ncei.noaa.gov/contact
language 
                                            []
license https://creativecommons.org/publicdomain/zero/1.0/
modified 2015-04-22T00:00:00.000+00:00
publisher 
                                            {
  "name": "NOAA National Centers for Environmental Information",
  "@type": "org:Organization"
}
references 
                                            [
  "https://doi.org/10.7289/v5445jkv",
  "https://doi.org/10.7289/v57w698t",
  "https://doi.org/10.7289/v5pg1ptj",
  "https://www.ncei.noaa.gov/archive/accession/0163992",
  "https://www.ncei.noaa.gov/archive/accession/0163993",
  "https://coastalscience.noaa.gov/project/estuarine-species-database-noaa-estuarine-living-marine-resources-program/"
]
rights otherRestrictions
spatial -66.9,24.8,-124.5,48.5
temporal 1999-01-01T00:00:00+00:00/1999-12-31T00:00:00+00:00
title Estuarine Salinity Zones in US East Coast, Gulf of Mexico, and US West Coast from 1999-01-01 to 1999-12-31 (NCEI Accession 0127396)

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