Extreme Water Levels from CO-OPS
Data Set (DS) | Center for Operational Oceanographic Products and Services (CO-OPS)GUID: gov.noaa.nmfs.inport:69876 | Updated: July 17, 2023 | Published / External
Summary
Short Citation
Center for Operational Oceanographic Products and Services, 2025: Extreme Water Levels from CO-OPS, https://www.fisheries.noaa.gov/inport/item/69876.
Full Citation Examples
Extremely high or low water levels at coastal locations are an important public concern and a factor in coastal hazard assessment, navigational safety, and ecosystem management. The probability that water levels will exceed a given elevation is based on a statistical analysis of historical extremely high and low water levels. This product provides annual exceedance probability levels for select Center for Operational Oceanographic Products and Services (CO-OPS) water level stations with at least 30 years of data. When used in conjunction with real-time station data, exceedance probability levels can be used to evaluate current conditions and determine whether a rare event is occurring. This information may also be instrumental in planning for the possibility of dangerously high or low water events at a local level.
The extreme levels measured by the CO-OPS tide gauges during storms are called storm tides, which are the total observed seawater level during a storm, resulting from the combination of storm surge and the astronomical tide. They do not include wave runup, the movement of water up a slope. Therefore, the 1% annual exceedance probability levels do not necessarily correspond to the Base Flood Elevations (BFE) defined by the Federal Emergency Management Administration (FEMA), which are the basis for the National Flood Insurance Program. The 1% annual exceedance probability levels more closely correspond to FEMA's Still Water Flood Elevations (SWEL). The peak levels from tsunamis, which can cause high-frequency fluctuations at some locations, have not been included in this statistical analysis due to their infrequency during the periods of historic record.
Distribution Information
-
CO-OPS Derived Products API
-
CO-OPS Extreme Water Levels page
None.
While most of the results are based on verified data, there are situations where a station malfunctions during a storm, but post-storm visits allow to discern how high the water reached from a mud/debris line on site or at nearby buildings. If the debris lines are leveled to the station bench marks or to a known datum such as NAVD88, that was added to the instrument-observed levels as the maximum for that month. None of that information is captured in any of our other published products. An accurate exceedance probability analysis strongly depends on not missing the most extreme levels during the period of observations.
Controlled Theme Keywords
climatologyMeteorologyAtmosphere, COMPOUND EXTREME EVENTS, EXTREME WEATHER, FLOODING, geoscientificInformation, MARINE ENVIRONMENT MONITORING, OCEANS, oceans, SEA SURFACE HEIGHT, STORM SURGE, TIDAL HEIGHT, TIDAL HEIGHT, TIDAL RANGE, TIDES
Child Items
No Child Items for this record.
Contact Information
Point of Contact
Stakeholder Services Branch
tide.predictions@noaa.gov
301-713-2815
Metadata Contact
Stakeholder Services Branch
tide.predictions@noaa.gov
301-713-2815
Extents
-180° W,
180° E,
61.3° N,
-14.3° S
2013 - Present
Item Identification
Title: | Extreme Water Levels from CO-OPS |
---|---|
Short Name: | Extreme Water Levels |
Status: | On Going |
Creation Date: | 2013 |
Publication Date: | 2013 |
Abstract: |
Extremely high or low water levels at coastal locations are an important public concern and a factor in coastal hazard assessment, navigational safety, and ecosystem management. The probability that water levels will exceed a given elevation is based on a statistical analysis of historical extremely high and low water levels. This product provides annual exceedance probability levels for select Center for Operational Oceanographic Products and Services (CO-OPS) water level stations with at least 30 years of data. When used in conjunction with real-time station data, exceedance probability levels can be used to evaluate current conditions and determine whether a rare event is occurring. This information may also be instrumental in planning for the possibility of dangerously high or low water events at a local level. The extreme levels measured by the CO-OPS tide gauges during storms are called storm tides, which are the total observed seawater level during a storm, resulting from the combination of storm surge and the astronomical tide. They do not include wave runup, the movement of water up a slope. Therefore, the 1% annual exceedance probability levels do not necessarily correspond to the Base Flood Elevations (BFE) defined by the Federal Emergency Management Administration (FEMA), which are the basis for the National Flood Insurance Program. The 1% annual exceedance probability levels more closely correspond to FEMA's Still Water Flood Elevations (SWEL). The peak levels from tsunamis, which can cause high-frequency fluctuations at some locations, have not been included in this statistical analysis due to their infrequency during the periods of historic record. |
Purpose: |
This dataset provides statistical analysis showing the likelihood of water levels exceeding a given elevation for select NOAA stations, given the difficulty in recreating the same series from observed data. |
Supplemental Information: |
Because these levels are station specific, their use for evaluating surrounding areas may be limited. A NOAA Technical Report, "Extreme Water Levels of the United States 1893-2010" describes the methods and data used in the calculation of the exceedance probability levels. Additionally, Section 3.2 of the "2022 Sea Level Rise Technical Report" discusses regional frequency analysis of tide gauge data. The datasets that were analyzed consist of a series of verified monthly maximum and minimum water levels. The series were detrended before selecting annual maximum and minimum water levels. Additionally, while most of the results are based on verified data, there are situations where a station malfunctions during a storm, but post-storm visits allow to discern how high the water reached from a mud/debris line on site or at nearby buildings. If the debris lines are leveled to the station bench marks or to a known datum such as NAVD88, that was added to the instrument-observed levels as the maximum for that month. None of that information is captured in any of our other published products. An accurate exceedance probability analysis strongly depends on not missing the most extreme levels during the period of observations. |
Keywords
Theme Keywords
Thesaurus | Keyword |
---|---|
Global Change Master Directory (GCMD) Science Keywords |
EARTH SCIENCE > CLIMATE INDICATORS > ATMOSPHERIC/OCEAN INDICATORS > COMPOUND EXTREME EVENTS
|
Global Change Master Directory (GCMD) Science Keywords |
EARTH SCIENCE > CLIMATE INDICATORS > ATMOSPHERIC/OCEAN INDICATORS > EXTREME WEATHER
|
Global Change Master Directory (GCMD) Science Keywords |
EARTH SCIENCE > LAND SURFACE > GEOMORPHIC LANDFORMS/PROCESSES > COASTAL PROCESSES > FLOODING
|
Global Change Master Directory (GCMD) Science Keywords |
EARTH SCIENCE > OCEANS
|
Global Change Master Directory (GCMD) Science Keywords |
EARTH SCIENCE > OCEANS > COASTAL PROCESSES > SEA SURFACE HEIGHT
|
Global Change Master Directory (GCMD) Science Keywords |
EARTH SCIENCE > OCEANS > COASTAL PROCESSES > TIDAL HEIGHT
|
Global Change Master Directory (GCMD) Science Keywords |
EARTH SCIENCE > OCEANS > MARINE ENVIRONMENT MONITORING
|
Global Change Master Directory (GCMD) Science Keywords |
EARTH SCIENCE > OCEANS > TIDES
|
Global Change Master Directory (GCMD) Science Keywords |
EARTH SCIENCE > OCEANS > TIDES > STORM SURGE
|
Global Change Master Directory (GCMD) Science Keywords |
EARTH SCIENCE > OCEANS > TIDES > TIDAL HEIGHT
|
Global Change Master Directory (GCMD) Science Keywords |
EARTH SCIENCE > OCEANS > TIDES > TIDAL RANGE
|
ISO 19115 Topic Category |
climatologyMeteorologyAtmosphere
|
ISO 19115 Topic Category |
geoscientificInformation
|
ISO 19115 Topic Category |
oceans
|
UNCONTROLLED | |
None | coastal monitoring |
None | Coastal Sea LevelStations |
None | NWLON > National Water Level Observation Network |
None | NWLON station |
None | PORTS > Physical Oceanographic Real-Time System |
None | storm tide |
None | tides and currents |
None | water level predictions |
Spatial Keywords
Thesaurus | Keyword |
---|---|
Global Change Master Directory (GCMD) Location Keywords |
CONTINENT
|
Global Change Master Directory (GCMD) Location Keywords |
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > ALABAMA
|
Global Change Master Directory (GCMD) Location Keywords |
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > ALASKA
|
Global Change Master Directory (GCMD) Location Keywords |
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > CALIFORNIA
|
Global Change Master Directory (GCMD) Location Keywords |
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > CONNECTICUT
|
Global Change Master Directory (GCMD) Location Keywords |
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > DELAWARE
|
Global Change Master Directory (GCMD) Location Keywords |
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > DISTRICT OF COLUMBIA
|
Global Change Master Directory (GCMD) Location Keywords |
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > FLORIDA
|
Global Change Master Directory (GCMD) Location Keywords |
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > GEORGIA
|
Global Change Master Directory (GCMD) Location Keywords |
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > HAWAII
|
Global Change Master Directory (GCMD) Location Keywords |
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > LOUISIANA
|
Global Change Master Directory (GCMD) Location Keywords |
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > MAINE
|
Global Change Master Directory (GCMD) Location Keywords |
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > MARYLAND
|
Global Change Master Directory (GCMD) Location Keywords |
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > MASSACHUSETTS
|
Global Change Master Directory (GCMD) Location Keywords |
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > MISSISSIPPI
|
Global Change Master Directory (GCMD) Location Keywords |
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > NEW HAMPSHIRE
|
Global Change Master Directory (GCMD) Location Keywords |
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > NEW JERSEY
|
Global Change Master Directory (GCMD) Location Keywords |
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > NEW YORK
|
Global Change Master Directory (GCMD) Location Keywords |
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > NORTH CAROLINA
|
Global Change Master Directory (GCMD) Location Keywords |
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > OREGON
|
Global Change Master Directory (GCMD) Location Keywords |
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > PENNSYLVANIA
|
Global Change Master Directory (GCMD) Location Keywords |
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > RHODE ISLAND
|
Global Change Master Directory (GCMD) Location Keywords |
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > SOUTH CAROLINA
|
Global Change Master Directory (GCMD) Location Keywords |
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > TEXAS
|
Global Change Master Directory (GCMD) Location Keywords |
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > VIRGINIA
|
Global Change Master Directory (GCMD) Location Keywords |
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > WASHINGTON
|
Global Change Master Directory (GCMD) Location Keywords |
OCEAN > ATLANTIC OCEAN > NORTH ATLANTIC OCEAN > BERMUDA
|
Global Change Master Directory (GCMD) Location Keywords |
OCEAN > ATLANTIC OCEAN > NORTH ATLANTIC OCEAN > CARIBBEAN SEA
|
Global Change Master Directory (GCMD) Location Keywords |
OCEAN > ATLANTIC OCEAN > NORTH ATLANTIC OCEAN > CARIBBEAN SEA > PUERTO RICO
|
Global Change Master Directory (GCMD) Location Keywords |
OCEAN > ATLANTIC OCEAN > NORTH ATLANTIC OCEAN > CARIBBEAN SEA > VIRGIN ISLANDS
|
Global Change Master Directory (GCMD) Location Keywords |
OCEAN > ATLANTIC OCEAN > NORTH ATLANTIC OCEAN > GULF OF MEXICO
|
Global Change Master Directory (GCMD) Location Keywords |
OCEAN > PACIFIC OCEAN > CENTRAL PACIFIC OCEAN > AMERICAN SAMOA
|
Global Change Master Directory (GCMD) Location Keywords |
OCEAN > PACIFIC OCEAN > CENTRAL PACIFIC OCEAN > HAWAIIAN ISLANDS
|
Global Change Master Directory (GCMD) Location Keywords |
OCEAN > PACIFIC OCEAN > CENTRAL PACIFIC OCEAN > JOHNSTON ATOLL
|
Global Change Master Directory (GCMD) Location Keywords |
OCEAN > PACIFIC OCEAN > CENTRAL PACIFIC OCEAN > MIDWAY ATOLL
|
Global Change Master Directory (GCMD) Location Keywords |
OCEAN > PACIFIC OCEAN > CENTRAL PACIFIC OCEAN > WAKE ISLAND
|
Global Change Master Directory (GCMD) Location Keywords |
OCEAN > PACIFIC OCEAN > WESTERN PACIFIC OCEAN > MICRONESIA > GUAM
|
Global Change Master Directory (GCMD) Location Keywords |
OCEAN > PACIFIC OCEAN > WESTERN PACIFIC OCEAN > MICRONESIA > MARSHALL ISLANDS
|
UNCONTROLLED | |
None | Coastal U.S. territories |
None | Coastal United States |
Instrument Keywords
Thesaurus | Keyword |
---|---|
Global Change Master Directory (GCMD) Instrument Keywords |
ACOUSTIC SOUNDERS
|
Global Change Master Directory (GCMD) Instrument Keywords |
PRESSURE SENSORS > PRESSURE SENSORS
|
Global Change Master Directory (GCMD) Instrument Keywords |
TIDE GAUGES > TIDE GAUGES
|
Global Change Master Directory (GCMD) Instrument Keywords |
WATER LEVEL GAUGES > WATER LEVEL GAUGES
|
UNCONTROLLED | |
None | Microwave Water Level (MWWL) Sensor |
Platform Keywords
Thesaurus | Keyword |
---|---|
Global Change Master Directory (GCMD) Platform Keywords |
GOES > NOAA Geostationary Operational Environmental Satellites
|
Physical Location
Organization: | Center for Operational Oceanographic Products and Services |
---|---|
City: | Silver Spring |
State/Province: | MD |
Data Set Information
Data Set Scope Code: | Data Set |
---|---|
Data Set Type: | Mixed |
Maintenance Frequency: | Annually |
Data Presentation Form: | Plots, downloadable data (CSV, JSON, XML) |
Entity Attribute Overview: |
Sensors used at our non-Great Lakes stations are acoustic or microwave water level (MWWL) with pressure sensor (bubbler) as the back-up sensor. The type of sensor used depends on the station's environment. The lack of infrastructure may prevent the use of the desired sensor type at that location. |
Entity Attribute Detail Citation: |
Latest detailed information on sensors and accuracy can be found at: https://tidesandcurrents.noaa.gov/publications/CO-OPS_Measurement_Spec.pdf |
Entity Attribute Detail URL: | https://tidesandcurrents.noaa.gov/publications/CO-OPS_Measurement_Spec.pdf |
Distribution Liability: |
While most of the results are based on verified data, there are situations where a station malfunctions during a storm, but post-storm visits allow to discern how high the water reached from a mud/debris line on site or at nearby buildings. If the debris lines are leveled to the station bench marks or to a known datum such as NAVD88, that was added to the instrument-observed levels as the maximum for that month. None of that information is captured in any of our other published products. An accurate exceedance probability analysis strongly depends on not missing the most extreme levels during the period of observations. |
Data Set Credit: | NOAA's National Ocean Service, CO-OPS |
Support Roles
Data Steward
Date Effective From: | 2023-05-09 |
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Date Effective To: | |
Contact (Position): | Stakeholder Services Branch |
Email Address: | tide.predictions@noaa.gov |
Phone: | 301-713-2815 |
Distributor
Date Effective From: | 2023-05-09 |
---|---|
Date Effective To: | |
Contact (Organization): | Center for Operational Oceanographic Products and Services (CO-OPS) |
URL: | Tides and Currents |
Metadata Contact
Date Effective From: | 2023-05-09 |
---|---|
Date Effective To: | |
Contact (Position): | Stakeholder Services Branch |
Email Address: | tide.predictions@noaa.gov |
Phone: | 301-713-2815 |
Point of Contact
Date Effective From: | 2023-05-09 |
---|---|
Date Effective To: | |
Contact (Position): | Stakeholder Services Branch |
Email Address: | tide.predictions@noaa.gov |
Phone: | 301-713-2815 |
Extents
Currentness Reference: | Ground Condition |
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Extent Group 1
Extent Group 1 / Geographic Area 1
W° Bound: | -180 | |
---|---|---|
E° Bound: | 180 | |
N° Bound: | 61.3 | |
S° Bound: | -14.3 |
Extent Group 1 / Time Frame 1
Time Frame Type: | Continuing |
---|---|
Start: | 2013 |
Access Information
Security Class: | Unclassified |
---|---|
Data Access Constraints: |
None. |
Data Use Constraints: |
While most of the results are based on verified data, there are situations where a station malfunctions during a storm, but post-storm visits allow to discern how high the water reached from a mud/debris line on site or at nearby buildings. If the debris lines are leveled to the station bench marks or to a known datum such as NAVD88, that was added to the instrument-observed levels as the maximum for that month. None of that information is captured in any of our other published products. An accurate exceedance probability analysis strongly depends on not missing the most extreme levels during the period of observations. |
Distribution Information
Distribution 1
Start Date: | 2018 |
---|---|
End Date: | Present |
Download URL: | https://api.tidesandcurrents.noaa.gov/dpapi/prod/ |
Distributor: | Center for Operational Oceanographic Products and Services (CO-OPS) (2023-05-09 - Present) |
Description: |
CO-OPS Derived Products API |
File Type (Deprecated): | json, xml |
Distribution 2
Start Date: | 2013 |
---|---|
End Date: | Present |
Download URL: | https://tidesandcurrents.noaa.gov/est/ |
Distributor: | Center for Operational Oceanographic Products and Services (CO-OPS) (2023-05-09 - Present) |
Description: |
CO-OPS Extreme Water Levels page |
File Type (Deprecated): | html |
URLs
URL 1
URL: | https://tidesandcurrents.noaa.gov/sea_level_info.html |
---|---|
Name: | CO-OPS Sea Level and Coastal Flooding Information |
URL Type: |
Online Resource
|
Description: |
CO-OPS Sea Level and Coastal Flooding Information landing page |
URL 2
URL: | https://tidesandcurrents.noaa.gov/publications/NOAA_Technical_Report_NOS_COOPS_067a.pdf |
---|---|
Name: | Extreme Water Levels of the United States 1893-2010 |
URL Type: |
Online Resource
|
Description: |
2013 Technical Report on Extreme Water Levels |
URL 3
URL: | https://tidesandcurrents.noaa.gov/ |
---|---|
Name: | Home page for NOAA Tides and Currents |
URL Type: |
Online Resource
|
Description: |
CO-OPS main page |
Activity Log
Activity Log 1
Activity Date/Time: | 2023-05-09 |
---|---|
Activity Type: | Record created |
Activity Log 2
Activity Date/Time: | 2023-06-07 |
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Activity Type: | Record updated |
Responsible Party: | Shawn Maddock |
Description: |
Dataset manager |
Technical Environment
Description: |
Observed data are recorded and transmitted, then go through a quality control procedure and are loaded into a database. For Extreme Water Levels, typically the verified monthly and annual maxima/minima are used. Prior to the extreme analysis being completed, the long term sea level trend is removed so that maximum or minimum levels reached by an event in the past can be compared to an equivalent event today. |
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Data Quality
Accuracy: |
Observed data are recorded and transmitted, then go through a quality control procedure and are loaded into a database. For Extreme Water Levels, typically the verified monthly and annual maxima/minima are used. Prior to the extreme analysis being completed, the long term sea level trend is removed so that maximum or minimum levels reached by an event in the past can be compared to an equivalent event today. |
---|---|
Completeness Report: |
While most of the results are based on verified data, there are situations where a station malfunctions during a storm, but post-storm visits allow to discern how high the water reached from a mud/debris line on site or at nearby buildings. If the debris lines are leveled to the station bench marks or to a known datum such as NAVD88, that was added to the instrument-observed levels as the maximum for that month. None of that information is captured in any of our other published products. An accurate exceedance probability analysis strongly depends on not missing the most extreme levels during the period of observations. |
Conceptual Consistency: |
While most of the results are based on verified data, there are situations where a station malfunctions during a storm, but post-storm visits allow to discern how high the water reached from a mud/debris line on site or at nearby buildings. If the debris lines are leveled to the station bench marks or to a known datum such as NAVD88, that was added to the instrument-observed levels as the maximum for that month. None of that information is captured in any of our other published products. An accurate exceedance probability analysis strongly depends on not missing the most extreme levels during the period of observations. |
Lineage
Lineage Statement: |
Observed data are recorded and transmitted, then go through a quality control procedure and are loaded into a database. For Extreme Water Levels, typically the verified monthly and annual maxima/minima are used. Prior to the extreme analysis being completed, the long term sea level trend is removed so that maximum or minimum levels reached by an event in the past can be compared to an equivalent event today. |
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Sources
Water level data source
Contact Role Type: | Publisher |
---|---|
Contact Type: | Organization |
Contact Name: | National Oceanic and Atmospheric Administration (NOAA), National Ocean Service (NOS), Center for Operational Oceanographic Products and Services (CO-OPS) |
Extent Type: | Continuing |
Extent Start Date/Time: | 2013 |
Source Contribution: |
6-minute data from various water level instruments supporting the National Water Level Observation Network (NWLON). |
Process Steps
Process Step 1
Description: |
Verified water level data from a water level station (the verified 6-minute data, and the secondary datasets of highs and lows (except for Great Lakes stations), hourly heights, daily means (Great Lakes stations only), and monthly means) are made available roughly one month after collection. This is a 2-step process where one person reviews the data, and if necessary, removes erroneous data or fills gaps by either using data from the station's back-up sensor, predictions for that station, or similar data from proximal stations. With exception of the corrected errors or filled gaps, most preliminary (raw) 6-minute data become the verified 6-minute data. Secondary datasets are also generated during this step. Then a second person reviews the work of the first, and when satisfied, marks the data in the database as "verified." The order in which the 300+ water level stations are processed each month is random, to prevent the same stations or geographical locations from always being first or last. Verified water level data are made available on a monthly basis for the previous month's data. |
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Process Contact: | Center for Operational Oceanographic Products and Services (CO-OPS) |
Catalog Details
Catalog Item ID: | 69876 |
---|---|
GUID: | gov.noaa.nmfs.inport:69876 |
Metadata Record Created By: | Shawn Maddock |
Metadata Record Created: | 2023-05-09 17:38+0000 |
Metadata Record Last Modified By: | Shawn Maddock |
Metadata Record Last Modified: | 2023-07-17 16:19+0000 |
Metadata Record Published: | 2023-07-17 |
Owner Org: | CO-OPS |
Metadata Publication Status: | Published Externally |
Do Not Publish?: | N |
Metadata Last Review Date: | 2023-06-22 |
Metadata Review Frequency: | 1 Year |
Metadata Next Review Date: | 2024-06-22 |