Maritime Transportation:

What is a sonar?

Sonar, short for Sound Navigation and Ranging, is helpful for exploring and mapping the ocean because sound waves travel farther in the water than do radar and light waves. NOAA scientists primarily use sonar to develop nautical charts, locate underwater hazards to navigation, search for and map objects on the seafloor such as shipwrecks, and map the seafloor itself. There are two types of sonar—active and passive.


Sanctuaries: The Underwater Museum (Ocean Today)

There is good news for people that want to protect the oceans. And that is marine protected areas, but in particular, in the United States, it’s National Marine Sanctuaries.


Explore With Us (Ocean Today)

When I first started as a maritime archaeologist, you would go out in a boat, you would take a look at a spot on the land and another spot, and if they lined up right, you’d figure you were more or less over a shipwreck that you plotted, you’d jump into the water, you’d swim down, and there it would be. And you might share that with the other diver that was with you.


Leave Only Bubbles (Ocean Today)

One of the things that we’ve learned when we look at shipwrecks in particular but other parts of archaeology is when something is preserved, when it’s set aside, it’s almost like money that you put in the bank. But it’s money that you can’t make another deposit to. Once you start taking it out, it’s gone forever. That’s why as archaeologists, we’re very careful to look and not touch, more often than not. In the time I’ve been an archaeologist, I’ve seen the technology change so much that if I could go back and say, “Hold on! Don’t dig that ship up now! Let’s wait thirty years or forty years because we’ll learn twice as much!” I would go back and have that conversation with myself and others.


Adventures of a Maritime Archaeologist (Ocean Today)

So much of history has really been tightly kept in a little box that archaeology is now cracking open. I started in archaeology when I was fourteen.


What is Maritime Archaeology? (Ocean Today)

Maritime archaeology is the study, from what people leave behind, of how we as human beings have interacted with the oceans and with lakes and rivers.


Journey Through Time (Ocean Today)

I’ve seen ancient ships from a time when the Mediterranean was an expanding area of different cultures from ancient Egypt to the Phoenicians, to the rise of the Greeks and the Romans.


Ocean Time Capsules (Ocean Today)

The way archaeology works is often times it gives us information that isn’t in the history books. In some cases, there are no history books.


Mapping Goes Micro (Ocean Today)

In some areas, the maps used for navigation on the ocean, called nautical charts, still show information acquired in the 1800s, so there is a LOT of work to do!


Charting new waters (Podcast)

Boaters rely on NOAA's nautical charts for depth measurements so they don't accidentally ground on sandbars or other underwater obstructions. See how NOAA updates nautical charts with high tech tools—including new experimental ocean "robots" that are small enough to survey the nation's shallowest coastal areas.


Measuring water levels with microwaves (Podcast)

We visit a research station perched at the end of a long pier in Duck, North Carolina, to get a close-up look at the microwave radar water level sensor—a revolutionary step forward in how NOAA measures water levels around the nation.


Ocean as a Lab: Oil Spills (Ocean Today)

Hi, Im Chris Reddy, and Im an environmental chemist at Woods Hole Oceanographic Institution, and I study oil spills. This is Wild Harbor salt marsh in Cape Cod, Massachusetts.


Ocean as a Lab: Trouvadore Shipwreck (Ocean Today)

My name is Dr. Donald Keith. I'm a marine archeologist. I work in the Turks and Caicos Islands, British West Indies.


Travel the Seas (Ocean Today)

At first glance, a nautical chart may look overwhelming. But once you learn what the various lines, numbers, and symbols mean, reading these charts becomes a lot easier.


USS Monitor: The Ironclad Endures (Ocean Today)

It’s March 8, 1862 and an epic battle of the Civil War is underway in the waters off Hampton Roads, Virginia. The Confederate CSS Virginia faces off against its northern opponent, the USS Monitor.


Lessons from Valdez: 25 Years Later (Ocean Today)

On March 24, 1989, the Exxon Valdez grounded on Bligh Reef in Prince William Sound, rupturing the hull and spilling oil into the pristine waters of Alaska.


USS Monitor: Rediscovering the Ironclad (Ocean Today)

Ocean exploration is all about making new discoveries. But sometimes the most fascinating findings are when things are rediscovered. The USS Monitor was a civil war ironclad warship that sank in 1862.


Ghost Ships off the Golden Gate (Ocean Today)

In the waters off San Francisco Bay… in the Gulf of the Farallones National Marine Sanctuary… lie hundreds of mysteries.


Life at Sea (Ocean Today)

What is it like to work on a NOAA ship? Come aboard the NOAA Ship Thomas Jefferson where collecting data for NOAA nautical charts requires science and technology...but most importantly, passionate, ad ...


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