Description: Layer represents the geographic locations at which water level
observations are presently being collected. "Water level" is defined as the height of the water surface relative to a specific datum (base elevation). Most stations with water level observations provide readings every 6 minutes. CO-OPS measures water levels at over 200 tidal and non-tidal stations along the coast of the United States and its territories and around the Great Lakes. "Tide" is defined as the periodic rise and fall of a body of water resulting from gravitational interactions between Sun, Moon, and Earth. The time series on the CO-OPS website that are associated with these point locations contain both verified and unverified data. Unverified, or 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. This file also contains air gap stations which measure
clearance between a bridge and the water surface. Air gap measurements are updated every 6 minutes to account for changes in water level and bridge height, due to bridge traffic, air temperature, and other factors. Data from air gap sensors along with real-time data on water conditions like tides, currents, and winds, help ships safely navigate U.S. ports. More information can be found at
http://tidesandcurrents.noaa.gov/stations.html?type=Water+Levels
Description: Layer represents any geographic location at which tidal (water level)
observations have been collected and verified, including stations presently collecting observations. "Tide" is defined as the periodic rise and fall of a body of water resulting from gravitational interactions between Sun, Moon, and Earth. "Water level" is defined as the height of the water surface relative to a specific datum (reference elevation). Most stations with water level observations provide readings every 6 minutes. CO-OPS measures water levels at over 200 stations along the coast of the United States and its territories and around the Great Lakes. More information can be found at http://tidesandcurrents.noaa.gov/stations.html?type=Historic+Water+Levels
Description: Layer represents the geographic locations at which current (water
velocity) observations are presently being collected. Generally, "currents" are defined as a horizonal movement of water. Currents may be classified as tidal and nontidal. Tidal currents are caused by gravitational interactions among the sun, moon, and earth and are part of the same general movement of the sea that is manifested in the vertical rise and fall, called tide. Nontidal currents include the permanent currents in the general circulatory systems of the sea, as well as temporary currents arising from more pronounced meteorological variability. Most stations with current observations provide readings every 6 minutes. More information can be found at
http://tidesandcurrents.noaa.gov/cdata/StationList?type=Current+Data&filter=active
Description: Layer represents the geographic locations that are no longer active at
which current (water velocity) observations were collected. Generally, "currents" are defined as a horizonal movement of water. Currents may be classified as tidal and nontidal. Tidal currents are caused by gravitational interactions among the sun, moon, and earth and are part of the same general movement of the sea that is manifested in the vertical rise and fall, called tide. Nontidal currents include the permanent currents in the general circulatory systems of the sea, as well as temporary currents arising from more pronounced meteorological variability. Most stations with current observations provide readings every 6 minutes. Each year, CO-OPS measures currents at many coastal locations in order to provide accurate tidal current predictions for the maritime community. These data sets typically range from one to three months in length and at most locations, data are available throughout the water column. These data contain the raw current measurements taken during these surveys, which date back to 1997. Data
from formerly active (real-time) stations also can be found here. More information can be found at
http://tidesandcurrents.noaa.gov/cdata/StationList?type=Current+Data&filter=historic
http://tidesandcurrents.noaa.gov/cdata/StationList?type=Current+Data&filter=historic
Description: Layer represents the geographic locations of all past and present
meteorological stations. Many stations are equipped with meteorological sensors to collect meteorological observations in conjunction with water level data. The following observations may be retrieved from the CO-OPS website: wind speed and directions, air temperature, water temperature, barometric pressure, relative humidity, and visibility. Not every station has the full suite of sensors installed, and some meteorological stations are stand-alone. More information can be found at http://tidesandcurrents.noaa.gov/stations.html?type=Meteorological%20Observations
Description: This layer represents the geographic locations at which conductivity observations are being collected. Conductivity sensors act as a proxy for salinity by measuring the total concentration of ions in solution (i.e., a measure of water's capability to pass electrical flow). Conductivity in water is affected by the presence of inorganic dissolved salts such as chloride, nitrate, sulfate, and phosphate a
nions (ions that carry a negative charge) or sodium, magnesium, calcium, iron, and aluminum cations (ions that carry a positive charge). Conductivity is measured in microsiemens per centimeter (µs/cm) and can be converted, with temperature, to the international standard of Practical Salinity Units (PSU) by the UNESCO standard found at many websites and documented at
<a href="http://unesdoc.unesco.org/images/0005/000598/059832eb.pdf">
http://unesdoc.unesco.org/images/0005/000598/059832eb.pdf</a>
Description: Layer represents the geographic locations at which water temperature
observations are being collected. These stations measure the temperature of the water below the water surface. More information can be found at
http://tidesandcurrents.noaa.gov/stations.html?type=Physical%20Oceanography
Description: Layer represents the locations where air gap observations are presently being collected. Air gap stations measure the clearance between the designated low steel value of a bridge and the water surface. Air gap measurements are updated every 6 minutes to account for changes in water level and bridge height, due to bridge traffic, air temperature, and other factors. Data from air gap sensors along with real-time data on water conditions like tides, currents, and winds, help ships safely navigate U.S. ports.
The time series on the CO-OPS website that are associated with these point locations contain unverified data. Unverified, or 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.