The nation's ocean and coastal agency: Supporting coastal communities, promoting a robust economy, and protecting coastal and marine ecosystems
oyster farm in the Damriscotta River, Maine coastal wetlands Screen shot of NOAA sea level rise viewer An 1852 painting of the Robert J. Walker by W.A. K. Martin. Courtesy of The Mariners' Museum
coastal scene
Why do we study tides?

Scientists measure the times, heights, and extents of both the rise and fall of the tidal waters that support a number of different aspects of our daily lives.

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Graphic of oil tanker spilling oil with glaciers in background
Making Waves

Twenty-five years after Exxon Valdez, how is marine life in Alaska's Prince William Sound faring? NOAA biologist Gary Shigenaka joins us to talk about the legacy of this historic spill.

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About NOS

The National Ocean Service (NOS) translates science, tools and services into action, to address threats to coastal areas such as climate change, population growth, port congestion, and contaminants in the environment, all working towards healthy coasts and healthy economies.

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Miami coastline


Supporting healthy, resilient coastal communities.


Midway Atoll


Protecting the health, productivity, and diversity of our ocean.


NOAA Coast Survey vessel


Navigation, tides, currents, and geodesy.