Coastal Inundation

Our nation’s coasts are increasingly at risk from rising seas, changing water levels in the Great Lakes, and more frequent and intense storms. These changes are forcing communities to plan for and adapt to coastal flooding using time scales associated with both weather (hourly, daily, and weekly) and climate (seasonally, annually, by decade, and beyond).

Get Started

Access the most current information about climate change, its impacts, and future flooding.

• Climate Science Special Report: Fifth National Climate Assessment

  This authoritative report on climate change impacts, risks, and responses provides the scientific foundation to support informed decision-making across the United States. Chapter 9 covers coastal effects.

  The previous installment, the Fourth National Climate Assessment, was released in 2017–2018 over two volumes: Volume I, Chapter 12 covers sea level rise and Volume II, Chapter 8 covers coastal effects.

• Federal Flood Risk Management Standard Climate-Informed Science Approach State of the Science Report

  This report provides federal agencies, local officials, and others with the best available science about current and future flood risk, including the Climate-Informed Science Approach.

  Watch this video for an introduction to the Federal Flood Risk Management Standard (FFRMS).

  Use this job aid to determine if a proposed federally funded action will be located within an FFRMS floodplain.

• High-Tide Flooding: Monthly and Annual Outlook

  NOAA’s interactive products illustrate the frequency of tidally driven high-tide flooding predicted for the next meteorological year, as well as the likelihood for each day in the calendar year for specific locations.

• State of the Science Fact Sheet: Sea Level Rise and Coastal Flooding

  This summary provides the current state of the science related to sea level rise, its causes, future projections, and its impacts on coastal communities as developed by NOAA.

• 2022 Sea Level Rise Technical Report

  Provides decision-makers with the most up-to-date sea level rise projections available for all U.S. states and territories.

  Watch this video for an introduction to the technical report, and how your community can use it for adaptation planning.

  Access the Application Guide for the 2022 Sea Level Rise Technical Report for assistance with applying and integrating the information in the technical report into local sea level rise planning and adaptation decisions (also available in Spanish).

Access Key Data

Use these data to develop a comprehensive understanding of your community’s water levels.

• Sea Level Trends

  Changes in relative sea level, either a rise or fall, have been computed at 142 long-term water-level stations using a minimum span of 30 years of observations at each location.

• Extreme Water Levels

  This product provides annual and monthly exceedance probability levels for select NOAA water-level stations with at least 30 years of data. Exceedance probability is the likelihood that water levels will exceed a given elevation and is based on a statistical analysis of historic values.

• Water-Level Stations

  NOAA provides real-time water-level information that is updated every six minutes. Search for a station by name, or click on the map icon to search for a station by region.

• Great Lakes Water Levels

  Great Lakes water levels are continuously monitored by U.S. and Canadian federal agencies in the region through a binational partnership.

• NOAA Vertical Datum Transformation

  VDatum is a free software tool designed to vertically transform geospatial data among a variety of tidal, orthometric, and ellipsoidal vertical datums, allowing users to convert data from different horizontal/vertical references into a common system and enabling the fusion of diverse geospatial data in desired reference levels.

• Digital Coast Data Access Viewer

  Discover, customize, and download authoritative land cover, imagery, and lidar data from NOAA’s Digital Coast.

Visualize the Information

• Digital Coast Sea Level Rise Viewer

  Use this web mapping tool to visualize community-level impacts from coastal flooding or sea level rise (up to 10 feet above average high tides). Photo simulations of how future flooding might impact local landmarks are also provided, as well as data related to water depth, connectivity, flood frequency, socioeconomic vulnerability, wetland loss and migration, and mapping confidence.

• Digital Coast Coastal Flood Exposure Mapper

  Use this visualization tool to support communities that are assessing their coastal hazard risks and vulnerabilities. The tool creates a collection of user-defined maps that show the people, places, and natural resources exposed to coastal flooding.

• Digital Coast Lake Level Viewer (U.S. Great Lakes)

  This web-based tool creates visuals that capture lake level changes that range from six feet above to six feet below historical long-term average water levels in the Great Lakes. Potential shoreline and coastal impacts are also provided. This information can be used to determine appropriate preparations, including zoning restrictions, infrastructure improvements, and habitat conservation.

• Coastal Inundation Dashboard

  Real-time water levels, 48-hour forecasts of water levels, and historic flooding information are provided at a majority of coastal water-level stations operated by the National Ocean Service Center for Operational Oceanographic Products and Services.

• Digital Coast Adapting Stormwater Management for Coastal Floods

  This interactive website, developed for stormwater and floodplain managers and land use planners, incorporates tools and methods to derive critical coastal water-level thresholds, as well as assess the potential impacts of exceeding those thresholds on stormwater infrastructure.

• Climate Resilience Toolkit – Coastal Flood Risk Section

  This toolkit, designed to help people find and use tools, information, and subject matter expertise to build climate resilience, offers information from across the U.S. federal government in one easy-to-use location.

• Climate Explorer

  This tool provides interactive graphs and maps showing past and projected climate conditions for any county in the United States.

Communicate the Issue

• Coastal Inundation Mapping Training

  This course provides baseline information about the various types of flooding and teaches methods for mapping current flooding and potential coastal inundation scenarios using a GIS. Hands-on exercises help participants understand and apply the spatial methods covered in this course.

• Risk Communication Basics

  This publication helps community leaders understand and connect with stakeholders and inspire risk-wise behavior through improved communication. Topics include why people perceive risk differently, best practices for risk communication, and sample conversations.

• Building Risk Communication Skills

  This training provides insights into how and why people respond to risk, and helps participants develop new skills to better connect with a variety of audiences. Understanding and connecting with an audience’s diverse values and concerns can lead to a higher level of community engagement and can help motivate action to reduce risk.

• Flood Literacy Story Map

  Developed in an effort to work toward a consistent set of terminology for communicating about flooding, this story map provides clear and scientifically-accurate flood hazard definitions and other resources to improve communication between groups of professionals and the public.

Take Action

• National Coastal Resilience Fund

  This annual grant program provides funds to restore, increase, and strengthen natural infrastructure to protect coastal communities while also enhancing habitats for fish and wildlife.

• NOAA Climate Program Office Funding Opportunities

  These competitive research programs fund high-priority climate science, assessments, decision-support research, outreach, education, and capacity-building activities designed to advance our understanding of Earth’s climate system and foster the application of this knowledge in risk management and adaptation efforts.

• Effects of Sea Level Rise Program

  This program supports science that will inform management decisions to reduce the risks of flooding and sea level rise to coastal communities and determine the effectiveness of a range of different management actions that are being considered for improving coastal resilience.

• NOAA Office for Coastal Management Funding Opportunities

  Visit this page for open competitive grant announcements.

Additional Resources

• U.S. Army Corps of Engineers Sea Level Tracker
• U.S. Geological Survey Coastal Hazards Change Portal
• U.S. Geological Survey and U.S. Global Change Research Program
  Sea Level Change Interactive Viewer
Climate Central Surging Seas
• NASA Sea Level Projection Tool
• National Park Service Sea Level Rise Viewer