71336 Air Gap Data Set Published / External 37109 CO-OPS Metadata Library Library On Going 2004 2004 The Center for Operational Oceanographic Products and Services (CO-OPS) of the National Ocean Service (NOS), an organizational element of NOAA, operates and maintains a network of downward-looking long-range microwave sensors for determining the instantaneous clearance or air gap below bridges that span navigable waterways in the U.S. These observations are part of the National Physical Oceanographic Real-Time System (PORTS) Program. The data collected are used to ensure safety of navigation, improve economic efficiency, and protect coastal resources. Included in this data collection are preliminary 6-minute air gap observations from various bridges spanning navigable waterways in the U.S. The mission of NOAA's National Ocean Service's (NOS) Center for Operational Oceanographic Products and Services (CO-OPS) is to provide the national infrastructure, and the scientific and technical expertise to monitor, assess, and distribute tide, water level, tidal current, meteorological and other coastal oceanographic products and services necessary to support NOAA's mission. Air gap data are provided through the Physical Oceanographic Real-Time System (PORTS (trademark)) partnership. Under the appropriation specific to PORTS (trademark), CO-OPS manages services for data ingestion, processing, 24-hour real-time monitoring and dissemination of the data. Air gap data and surrounding tides, currents, and meteorological conditions help vessel pilots safely enter and leave many seaports. This information is critical for pilots to safely navigate a ship under a bridge, especially as U.S. seaports grow and vessels continue to increase in size. https://doi.org/10.25921/6tey-xa23 NOAA Spatial Global Change Master Directory (GCMD) Location Keywords CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > CALIFORNIA Spatial Global Change Master Directory (GCMD) Location Keywords CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > DELAWARE Spatial Global Change Master Directory (GCMD) Location Keywords CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > FLORIDA Spatial Global Change Master Directory (GCMD) Location Keywords CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > GEORGIA Spatial Global Change Master Directory (GCMD) Location Keywords CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > LOUISIANA Spatial Global Change Master Directory (GCMD) Location Keywords CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > MARYLAND Spatial Global Change Master Directory (GCMD) Location Keywords CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > NEW JERSEY Spatial Global Change Master Directory (GCMD) Location Keywords CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > NEW YORK Spatial Global Change Master Directory (GCMD) Location Keywords CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > PENNSYLVANIA Spatial Global Change Master Directory (GCMD) Location Keywords CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > SOUTH CAROLINA Instrument Global Change Master Directory (GCMD) Instrument Keywords AMI > Active Microwave Instrument Theme Air Gap Theme PORTS > Physical Oceanographic Real-Time System Center for Operational Oceanographic Products and Services Silver Spring MD Data Set mixed As Needed Plots, downloadable data (CSV, JSON, XML) An Air Gap sensor is a downward-looking long-range microwave instrument used for determining the instantaneous clearance (air gap) below various bridges or overpasses that span navigable waterways in the U.S. The data collected are used to ensure safety of navigation, improve economic efficiency, and protect coastal resources. These real-time data are provided at 6-minute intervals. They are released for limited public use as preliminary data, to be used only with appropriate caution when clearing the bridge. Latest detailed information on sensors and accuracy can be found at: https://tidesandcurrents.noaa.gov/publications/CO-OPS_Measurement_Spec.pdf https://tidesandcurrents.noaa.gov/publications/CO-OPS_Measurement_Spec.pdf The air gap systems have been created by NOAA/NOS to provide the maritime community with improved information of bridge clearances. These real-time data are accurate to within +/- 1 inch. They are released for limited public use as preliminary data, to be used only with appropriate caution when clearing the bridge. NOAA's National Ocean Service, CO-OPS, and the PORTS Partnerships Data Steward 2016 Position Stakeholder Services Branch tide.predictions@noaa.gov 301-713-2815 Distributor 2023 Organization Center for Operational Oceanographic Products and Services CO-OPS https://ror.org/05vcng590 https://tidesandcurrents.noaa.gov/ Tides and Currents Online Resource https://tidesandcurrents.noaa.gov// Metadata Contact 2023 Position Stakeholder Services Branch tide.predictions@noaa.gov 301-713-2815 Point of Contact 2023 Position Stakeholder Services Branch tide.predictions@noaa.gov 301-713-2815 Ground Condition -123 -74 41 27 Continuing 2004-11 Yes Topology 1D Geographic 2D EPSG:4269 NAD83 North American Datum 1983 GRS 1980 6378137 298.257222101 1 Geodetic Latitude Lat degree north 1 Geodetic Latitude Lat degree north 2 Geodetic Longitude Lon degree east 2 Geodetic Longitude Lon degree east Geographic 2D EPSG:4326 WGS 84 World Geodetic System 1984 WGS 84 6378137 298.257223563 1 Geodetic Lattitude Lat degree north 2 Geodetic Longitude Lon degree east Unclassified none The air gap systems have been created by NOAA/NOS to provide the maritime community with improved information of bridge clearances. These real-time data are accurate to within +/- 1 inch. They are released for limited public use as preliminary data to be used only with appropriate caution when clearing the bridge. https://api.tidesandcurrents.noaa.gov/api/prod/ 2023 Organization Center for Operational Oceanographic Products and Services https://ror.org/05vcng590 Download present or historical air gap data, in CSV, JSON or XML format. Not Applicable https://tidesandcurrents.noaa.gov/api-helper/url-generator.html 2023 Organization Center for Operational Oceanographic Products and Services https://ror.org/05vcng590 This application builds a URL based off of inputted parameters that links to our various APIs. It can be used to make a link that returns data. Select one of the following to begin. Not Applicable https://tidesandcurrents.noaa.gov/map/ 2023 Organization Center for Operational Oceanographic Products and Services https://ror.org/05vcng590 An interactive map with many features designed to provide a quick and easy way to find a Center for Operational Oceanographic Products and Services (CO-OPS) station, including Air Gap data. The map can be used to view and/or download data from real-time observations, historical observations, and predictions of tides and tidal currents, though air gap data is limited to viewing the values from yesterday and today, without download capability. Not Applicable https://tidesandcurrents.noaa.gov/ports_info.html 2023 Organization Center for Operational Oceanographic Products and Services https://ror.org/05vcng590 Viewable graphics on HTML pages. Not Applicable Organization NOAA National Centers for Environmental Information https://ror.org/04r0wrp59 NCEI ncei.info@noaa.gov doi:10.25921/6tey-xa23 CO-OPS_Bridge_Air_Gap_Collection https://www.ncei.noaa.gov/metadata/geoportal/rest/metadata/item/gov.noaa.ncei:CO-OPS_Bridge_Air_Gap_Collection/html 2026-07-23T13:11:31 2026-07-23T13:11:31 https://tidesandcurrents.noaa.gov/ Home page for Tides and Currents Online Resource HTML CO-OPS main page 2023-11-21 Record creation Maddock, Shawn 2023-11-30 Finish building this record Maddock, Shawn Completed building this record Observed data are recorded and transmitted; then go through a quality control procedure and are loaded into a database. The air gap systems have been created by NOAA/NOS to provide the maritime community with improved information of bridge clearances. These real-time data are accurate to within +/- 1 inch. They are released for limited public use as preliminary data, to be used only with appropriate caution when clearing the bridge. For CO-OPS to adhere to its goal of reliable operation of PORTS and dissemination of quality data, this requires no more than five (5) percent down time or malfunction of any of its systems. This dictates that PORTS be maintained rigorously by personnel with the required expertise. Raw data have not been subjected to the National Ocean Service's quality control or quality assurance procedures and do not meet the criteria and standards of official National Ocean Service data. They are released for limited public use as preliminary data to be used only with appropriate caution. Air gap observations are collected at a high frequency and updated for the public every six minutes to account for changes in water level, vehicular loads on the bridge, air temperature, and other factors. Air Gap Data Source Organization National Oceanic and Atmospheric Administration (NOAA), National Ocean Service (NOS), Center for Operational Oceanographic Products and Services (CO-OPS) Publisher Continuing 2004-11 1 downward-looking long-range microwave sensors for determining the instantaneous clearance or air gap below bridges that span navigable waterways in the U.S. 2004-11-01T00:00:00 Organization Center for Operational Oceanographic Products and Services CO-OPS https://ror.org/05vcng590 https://tidesandcurrents.noaa.gov/ Tides and Currents Online Resource gov.noaa.nmfs.inport:71336 Shawn Maddock 2023-11-09T14:08:01 Tigist Jima 2026-07-23T13:11:31 2024-01-18 Center for Operational Oceanographic Products and Services CO-OPS 1002 Public No No 2024-01-18 2 Years 2026-01-18