remiconnesson/oceanservice-noaa-facts huggingface dataset:
# What is a red tide?

VIDEO: Learn about "red tides" and human health in this video from the [U.S. Integrated Ocean Observing System®](https://ioos.noaa.gov/).

Harmful algal blooms, or HABs, occur when colonies of algae—plant-like organisms that live in the sea and freshwater—grow out of control while producing toxic or harmful effects on people, fish, shellfish, marine mammals, and birds. The human illnesses caused by HABs, though rare, can be debilitating or even fatal.

While many people call these blooms 'red tides,' scientists prefer the term harmful algal bloom. One of the best known HABs in the nation occurs nearly every summer along Florida’s Gulf Coast. This bloom, like many HABs, is caused by microscopic algae that produce toxins that kill fish and make shellfish dangerous to eat. The toxins may also make the surrounding air difficult to breathe. As the name suggests, the bloom of algae often turns the water red.

HABs have been reported in every U.S. coastal state, and their occurrence may be on the rise. HABs are a national concern because they affect not only the health of people and marine ecosystems, but also the 'health' of local and regional economies.

But not all algal blooms are harmful. Most blooms, in fact, are beneficial because the tiny plants are food for animals in the ocean. In fact, they are the major source of energy that fuels the ocean food web.

A small percentage of algae, however, produce powerful toxins that can kill fish, shellfish, mammals, and birds, and may directly or indirectly cause illness in people. HABs also include blooms of non-toxic species that have harmful effects on marine ecosystems. For example, when masses of algae die and decompose, the decaying process can deplete oxygen in the water, causing the water to become so low in oxygen that animals either leave the area or die.

Scientists at the National Ocean Service have been monitoring and studying this phenomenon for a number of years to determine how to detect and forecast the location of the blooms. The goal is to give communities advance warnings so they can adequately plan for and deal with the adverse environmental and health effects associated with these 'red-tide' events.
# What species live in and around coral reefs?

## Millions of species live in and around coral reefs

![coral species](coral-species.jpg "coral species")

Coral reefs are home to millions of species.

Hidden beneath the ocean waters, coral reefs teem with life. Fish, corals, lobsters, clams, seahorses, sponges, and sea turtles are only a few of the thousands of creatures that rely on reefs for their survival.

Coral reefs are also living museums and reflect thousands of years of history. Many U.S. coral reefs were alive and thriving centuries before the European colonization of the nearby shores. Some reefs are even older than our old-growth redwood forests. They are an integral part of many cultures and our natural heritage.

Today, these important habitats are threatened by a range of human activities. Many of the world’s reefs have already been destroyed or severely damaged by water pollution, overfishing and destructive fishing practices, disease, global climate change, and ship groundings. However, we can still protect and preserve our remaining reefs by acting now.
# How do coral reefs benefit the economy?

_VIDEO: How do coral reefs benefit the economy? Here's an overview in under two minutes. [Transcript](#transcript)_

Healthy coral reefs support commercial and subsistence fisheries as well as jobs and businesses through tourism and recreation. Approximately half of all federally managed fisheries depend on coral reefs and related habitats for a portion of their life cycles. The National Marine Fisheries Service estimates the commercial value of U.S. fisheries from coral reefs is over $100 million.

Local economies also receive billions of dollars from visitors to reefs through diving tours, recreational fishing trips, hotels, restaurants, and other businesses based near reef ecosystems.

Despite their great economic and recreational value, coral reefs are severely threatened by pollution, disease, and habitat destruction. Once coral reefs are damaged, they are less able to support the many creatures that inhabit them. When a coral reef supports fewer fish, plants, and animals, it also loses value as a tourist destination.

### Video Transcript

Healthy Corals are the foundation of our ocean’s food chain, from tiny plankton to the largest animals in the sea. And coral reefs are important to our economy, too. Healthy coral reefs contribute to fishing and tourism, providing millions of jobs and contributing to economies all over the world. Scientists develop important drugs from coral reef organisms as treatments for cancer, arthritis, and viruses. But corals are threatened by pollution and climate change. So we must protect our coral reefs. Because coral reefs are an important part of earth’s fragile ecosystem. We all benefit from a healthy planet and healthy coral reefs!
# What is an oil spill trajectory?

## A map that shows where spilled oil is likely to travel and which shorelines and other environmentally or culturally sensitive areas might be at risk.

 [](/facts/oilspill-trajectory.mp4) 

VIDEO: Predicting where oil may go in the water is no easy task. Here's what you need to know in a minute. [Transcript](#transcript)

During the threat of an oil spill, responders need to know where that spilled oil will go in order to protect shorelines with containment boom, stage cleanup equipment, or close areas for fishing and boating.

In order to answer these questions, NOAA oceanographers use specialized computer models to predict the movement of spilled oil on the water surface. They predict where the oil is most likely to go and how soon it may arrive there. During a major spill response, trajectory maps are created to show predictions for the path of spilled oil.

Trajectory maps are produced using a [NOAA-developed computer model called GNOME](https://response.restoration.noaa.gov/oil-and-chemical-spills/oil-spills/response-tools/gnome.html) (General NOAA Operational Modeling Environment), which helps to predict the movement of oil. GNOME can forecast the effects that currents, winds, and other physical processes have on the movement of oil in the ocean. During an oil spill, this model is updated daily based on field observations, aerial surveys, and new forecasts for ocean currents and winds.

In addition to showing oiled locations and potential beached oil on a trajectory map, oceanographers will also include an uncertainty boundary on the map to indicate other locations where oil potentially could be located. This uncertainty boundary is necessary to account for differences in models as well as changes in currents and winds.

## Video Transcript

During the threat of an oil spill, NOAA predicts where the oil might spread. To predict where oil might go, we model how weather, wind, tides and currents affect oil movement. But natural variability in wind, weather and water currents can change the trajectory of a spill in ways difficult to predict. To get the best forecast possible we use aircraft and field observations to monitor the actual course and extent of an oil spill. These observations are then fed back into our computer model to improve the next forecast. Predicting the trajectory of an oil spill is tricky. But having better data and technology helps us show where oil is and where it could spread. NOAA continues to refine both current and emerging techniques in oil spill science.
# What is GPS?

![GPS Block IIR(M) Satellite](/facts/gps.jpg "The GPS Block IIR(M) Satellite, one of the various generations of GPS satellites.")

The GPS Block IIR(M) Satellite shown here is one of the various generations of GPS satellites orbiting the Earth. GPS satellites fly in medium Earth orbit at an altitude of approximately [20,200 Kilometers](#). Each satellite circles the Earth twice a day. The [satellites in the GPS constellation](http://www.gps.gov/systems/gps/space/) are arranged so that users can view at least four satellites from virtually any point on the planet.

##### **_Did you know?_**

The movements of Earth's surface in the U.S. are monitored by NOAA's [National Geodetic Survey](http://geodesy.noaa.gov/) through its nationwide network of permanent GPS stations called Continuously Operating Reference Stations. These stations makes it possible for NOAA to provide positioning products for use in surveying, construction, navigation, mapping, and other industries.

For thousands of years, humans found their way by looking to the sky. Sailors used the constellations, sun, and moon to navigate to distant shores. Today, all that's needed is a device called a GPS receiver. GPS stands for Global Positioning System, and it lets us know where we are and where we are going anywhere on Earth.

We still need objects in the sky to know where we are and how we get to other places, but now we use satellites instead of stars. Over 30 GPS navigation satellites are whizzing around the world, orbiting at an altitude of [20,200 Kilometers](#), to help us find our way.

GPS is a three-part system: satellites, ground stations, and receivers. Satellites act like the stars in constellations—we know where they are supposed to be at any given time. The ground stations monitor and control the satellites, and they help determine their locations—both where they were and where they are forecast to be. A receiver, like you might find in your phone or in your car, is constantly listening for signals from these satellites, which can be used like a giant tape measure between the receiver and satellites.

Once your receiver calculates its distance from four or more satellites, it knows exactly where you are. Within seconds, from thousands of miles up in space, your location on the ground can be determined with incredible precision, often within a few yards of your actual location. Many high-tech receivers can figure out where you are to within a fraction of an inch.

Did you know? - The movements of Earth's surface in the U.S. are monitored by NOAA's [National Geodetic Survey](http://geodesy.noaa.gov/) through its nationwide network of permanent GPS stations called Continuously Operating Reference Stations. These stations makes it possible for NOAA to provide positioning products for use in surveying, construction, navigation, mapping, and other industries.
# What is the Great Loop?

## The Great Loop is a continuous waterway that allows boaters to explore Eastern North America.

![Boating along the Erie Canal, part of the Great Loop (credit: Gladys Lorraine Buzzell)](/facts/great-loop960.jpg "Boating along the Erie Canal, part of the Great Loop (credit: Gladys Lorraine Buzzell)")

Boating along the Erie Canal, part of the Great Loop (image courtesy of Gladys L. Buzzell).

The Great Loop is a continuous waterway that recreational mariners can travel that includes part of the Atlantic, Gulf Intracoastal Waterways, the Great Lakes, Canadian Heritage Canals, and the inland rivers of America's heartland. Anyone who completes the journey is then named an official '[Looper](https://en.wikipedia.org/wiki/Great_Loop).'

For a safe and enjoyable trip, there are a few things to consider when traveling the Great Loop—a great amount of time, a boat with less than a five foot draft (recommended) to travel inland waterways, [NOAA nautical charts](https://www.nauticalcharts.noaa.gov/index.html), and a [NOAA radio](https://www.weather.gov/nwr/). Along the way, it is possible to visit a number of [national marine sanctuaries](https://sanctuaries.noaa.gov/) and [estuarine research reserves](https://coast.noaa.gov/nerrs/).

![Map showing the Great Loop (image courtesy of Raven Cove Publishing).](/facts/great-loop.jpg "Map showing the Great Loop (image courtesy of Raven Cove Publishing).")

Map showing the Great Loop (image courtesy of Raven Cove Publishing).

How does a boater embark on the Great Loop? If you start in Chicago, continue south in a counter-clockwise direction to take advantage of the river currents that run into the Mississippi River. While a few people stay on the Mississippi all the way to the Gulf of America (formerly Gulf of Mexico), most 'Loopers' choose to exit at the Tennessee River to avoid heavy barge traffic on the larger waterway. This path leads to the Tennessee-Tombigbee Waterway, which also flows to the Gulf.

Regardless of the Southern route selected, boaters can float downstream to the warm waters of the Gulf and explore the [Flower Garden Banks National Marine Sanctuary](https://flowergarden.noaa.gov/welcome.html). From there, cruise east on the Gulf's Intracoastal Waterway. While soaking up some Florida sun, visit the [Florida Keys National Marine Sanctuary](https://floridakeys.noaa.gov/welcome.html).

Then travel north up the Intracoastal Waterway and discover the [Gray's Reef National Marine Sanctuary](https://graysreef.noaa.gov/visit/welcome.html). Continue north on the Intracoastal to New York City. From the Big Apple, it's a straight shot up the Hudson to the Erie Canal. Then head west across to the Great Lakes. Boaters may visit [Thunder Bay National Marine Sanctuary](https://thunderbay.noaa.gov/welcome.html) when sailing up Lake Huron and then finally returning back to Chicago.
# What Does HAZMAT Stand For?

![ship near oil spill](/facts/hazmat.jpg "ship near oil spill")

_In January 2010, NOAA’s Office of Response and Restoration was notified of a collision between a crude oil tanker (T/V Eagle Otome) and a barge in Port Arthur, Texas._

HAZMAT is an abbreviation for “hazardous materials”—substances in quantities or forms that may pose a reasonable risk to health, property, or the environment. HAZMATs include such substances as toxic chemicals, fuels, nuclear waste products, and biological, chemical, and radiological agents.  HAZMATs may be released as liquids, solids, gases, or a combination or form of all three, including dust, fumes, gas, vapor, mist, and smoke.

HAZMAT [spills](http://response.restoration.noaa.gov/oil-and-chemical-spills) have caused health problems, injuries, and even death in people and animals, and have damaged buildings, homes, property, and the environment. Given such dire consequences, it is reasonable to conclude that one may not encounter HAZMATs on a daily basis. The truth, however, is that many products containing hazardous chemicals are routinely used and stored in homes, and are transported every day on the nation's highways, railroads, waterways, and pipelines.

### HAZMAT Incidents

Thousands of incidents occur each year in which HAZMATs are released into the environment as a result of accidents or natural disasters. In addition to potentially harming people and the environment, spills in coastal waters may cause substantial disruption of marine transportation with potential widespread economic impacts. Both coastal and inland spills are called HAZMAT incidents, and are routinely addressed by first responders like firefighters and local law enforcement.

### NOAA HAZMAT Response

Under the [National Contingency Plan](https://www.epa.gov/emergency-response/national-oil-and-hazardous-substances-pollution-contingency-plan-ncp-overview), NOAA provides scientific support to the [Federal On-Scene Coordinator](http://response.restoration.noaa.gov/oil-and-chemical-spills/oil-spills/resources/fosc-guide.html) for oil and other HAZMAT spills, and participates in emergency response activities in coastal and near-coastal waters.

NOAA's [Office of Response and Restoration](http://response.restoration.noaa.gov/oil-and-chemical-spills) responds to 150-175 HAZMAT incidents each year. Most are oil spills originating from leaking pipelines or vessel collisions, as well as hurricanes and drilling well blowouts, such as the 2010 _Deepwater Horizon_ spill in the Gulf of America.

For the thousands of minor incidents handled by first responders, NOAA and the U.S. Environmental Protection Agency collaborate on tools like the [CAMEO software suite](http://response.restoration.noaa.gov/oil-and-chemical-spills/chemical-spills/response-tools/cameo-software-suite.html) that offer fast access to chemical properties and other relevant information.
# How do natural disasters contribute to the marine debris problem?

Natural disasters such as hurricanes, tropical storms, [tsunamis](tsunami.html), and landslides have the potential to generate a tremendous amount of [marine debris](marinedebris.html). The high winds, heavy rains, [storm surge](stormsurge-stormtide.html), and flooding associated with these disasters can pull large structures, household articles, and outdoor items into surrounding waters.

As seen in the wakes of Hurricanes Katrina and Rita, and [post-tropical cyclone Sandy](/hazards/sandy/), some debris remains in shallow waters, creating safety hazards for people, obstructing navigation channels, and threatening natural resources. Immediate action is needed to assess and remove the debris in order to maintain navigation routes, ensure safe boating and recreational activities, and protect sensitive ecosystems.

Strong tides and currents also carry the debris out to sea, where it may take months to years to reach land again. The Japan earthquake of 2011 and the resulting tsunami destroyed whole communities, creating an estimated five million tons of debris. Much of this debris remained along the coast of Japan, but a portion of it was washed into the Pacific Ocean. While some of the wreckage eventually sank to the ocean floor, debris from the disaster occasionally continues to appear on U.S. and Canadian shores.
# When Was the First Earth Day?

![Cuyahoga River Fire Nov. 3, 1952. Courtesy of Cleveland Press Collection at Cleveland State University Library](/facts/earthday.jpg "Cuyahoga River Fire Nov. 3, 1952. Courtesy of Cleveland Press Collection at Cleveland State University Library")

 _Firefighters battle a fire on Ohio's Cuyahoga River in 1952. The polluted river caught fire on several occasions between 1936 and 1969, when debris and oil had concentrated on the water's surface and ignited. A blaze in 1969 came at a time of increasing environmental awareness and symbolized years of environmental neglect. Image courtesy of Cleveland Press Collection at Cleveland State University Library._

On June 22, 1969, the Cuyahoga River on the southern shores of Lake Erie caught on fire as chemicals, oil, and other industrial materials that had oozed into the river somehow ignited. Just a few months before, on January 28, 1969, an [oil rig leaked millions of gallons of oil off the coast of Santa Barbara](http://response.restoration.noaa.gov/about/media/45-years-after-santa-barbara-oil-spill-looking-historic-disaster-through-technology.html). That same year, reports surfaced that our national symbol, the bald eagle, was rapidly declining as a species due to the chemical DDT, while around the world, whales were being hunted nearly to extinction. These and other incidents caught the attention of the national media and galvanized public awareness of the many environmental insults being hurled at the nation and the planet.

In response to the public outcry, Earth Day Founder Gaylord Nelson, who served as the Governor of Wisconsin (1958-1962) and in the U.S. Senate (1963-1981), organized a nationwide "teach-in" about environmental issues to take place on April 22, 1970. More than 2,000 colleges and universities, 10,000 public schools, and 20 million citizens participated—nearly 10 percent of the U.S. population at that time.

This outpouring of grassroots environmental activism marked the first Earth Day—a recognition of the importance of caring for the environment and accepting stewardship responsibility for the nation's resources. It also helped establish a political climate conducive to forming both the National Oceanic and Atmospheric Administration (NOAA) and the U.S. Environmental Protection Agency (EPA) on October 3, 1970. 

We like to say that "Every day is Earth Day at NOAA." But ever since April 22, 1970, people the world over take time to recognize the importance of protecting the Earth's natural resources—be they oceanic, atmospheric, terrestrial, or biological—for future generations.
# Where is the largest estuary in the United States?

![Chesapeake Bay watershed](/facts/chesapeake-watershed.jpg "Chesapeake Bay Watershed")

_The largest estuary in North America, the Chesapeake Bay Watershed covers [64,000 square miles](#) and includes more than 150 rivers and streams that drain into the Bay. More than 300 species of fish, shellfish and crab species and a wide array of other wildlife call the Bay home. With almost 30 percent of area in agricultural production, the region’s over 83,000 farms generate more than $10 billion annually. The watershed encompasses parts of six states—Delaware, Maryland, New York, Pennsylvania, Virginia and West Virginia—and the entire District of Columbia._

The Chesapeake Bay is the largest estuary in the United States and is one of the most productive bodies of water in the world.

The Chesapeake [watershed](#) spans [165,759 square kilometers](#), covering parts of six states — Delaware, Maryland, New York, Pennsylvania, Virginia, West Virginia, and the District of Columbia. Over 17 million people live in this area.

The estuary and its network of streams, creeks, and rivers hold tremendous ecological, cultural, economic, historic, and recreational value for the region.

More than 250 fish species use the Bay and tributaries for some portion of their life cycles, including American and hickory shad, river herring, striped bass, eel, weakfish, bluefish, flounder, oysters, and blue crabs. More than 300 migratory bird species can also be found in the watershed. During the fall, the skies come alive as one million ducks, geese, and swans return to overwinter on the Chesapeake.
# What is air gap?

With an [air draft of 181 feet](#), the _Gunvor Maersk_ container ship transits under the Chesapeake Bay Bridge in Maryland at low tide on February 21, 2021. For this transit, NOAA's air gap sensor measured the Bay Bridge clearance (the distance from the water to the underside of the bridge) at [186 feet](#).

Air gap observations are collected at a high frequency and updated for the public every six minutes to account for changes in water level, vehicular loads on the bridge, air temperature, and other factors. Air gap data and surrounding tides, currents, and meteorological conditions help vessel pilots safely enter and leave many seaports. This information is critical for pilots to safely navigate a ship under a bridge, especially as U.S. seaports grow and vessels continue to increase in size.
# What is maritime heritage?

![The study of maritime heritage resources may include photo-documentation and archaeological site plans.](/facts/divers_st_peter.jpg)

_The study of maritime heritage resources may include photo-documentation and archaeological site plans._

Maritime heritage includes not only physical resources such as historic shipwrecks and prehistoric archaeological sites, but also archival documents and oral histories. Maritime heritage can also include the stories of indigenous cultures that have lived and used the oceans for thousands of years.

There is a maritime heritage component in each of our national marine sanctuaries and two national monuments, whether this is a shipwreck or study of indigenous cultures. The first sanctuary that was created with a maritime heritage component was the Monitor National Marine Sanctuary off the coast of North Carolina in 1975.

Maritime heritage resources are best studied without disturbing them and leaving them in place. In some rare cases, careful archaeological recovery followed by long-term conservation is done to preserve these artifacts in a museum for future generations.

Maritime heritage resources, when properly studied and interpreted, add an important dimension to our understanding and appreciation of our nation’s rich maritime legacy, and make us more aware of the critical need for us to be wise stewards of our ocean planet.