Bill Lindquist: Mapping the Ocean, May 9, 2013

NOAA Teacher at Sea
Bill Lindquist
Aboard NOAA Ship Rainier
May 6-16, 2013

Mission: Hydrographic surveys between Ketchikan and Petersburg, Alaska
Date: May 9, 2013

Weather on board. Taken at 1600 (4:00 in the afternoon)

Clear skies with a visibility of 10+ nautical miles
Light variable wind
Sea wave height – O
Air temperature 17.3° C
Water temperature 7.2° C

It's hard to get enough of this majestic view.

It’s hard to get enough of this majestic view.

Science and Technology Log: Mapping the Ocean

The work we do on board the Rainier is all centered on the task of gathering data of the ocean bottom – shoreline to shoreline. These data are used to update the nautical charts (maps) used by sailors. The project we have been working on is a section of Behm Canal in SE Alaska.

Nautical map of Behm Canal

Nautical map of Behm Canal

Hydrographic data on parts of this stretch of water haven’t been updated for over 100 years. The tools and methods utilized have changed significantly during that time. Hydrographers of 1900 lowered a rope tied to a lead weight to the ocean bottom. Measurements were taken on the length of rope. The area we were surveying ranges from 150 to over 300 fathoms (one fathom = 6 feet) deep – that is a lot of rope. At each measure, they sighted a bearing to two or more locations on shore to locate where on the chart they could mark the depth. It’s surprising how closely their data matches what we found with the use of sophisticated modern techniques.

So how is it done? A good activity in the classroom is to make a sounding box with an ocean floor shaped on the bottom of the box. The top is covered and marked with a grid. Skewer sticks can be inserted at the grid corners, pulled out, measured, and transferred to another grid. A map is made. If only it were as easy. Simply put, modern hydrographers ping sound waves (sonar) from the bottom of the ship. The sound waves travel through the water to the ocean bottom and bounce back. We know how fast sound travels so measurements of time can be made and the distance calculated – just like the skewer sticks. If only it were as easy!

See the following website for information on hydrographic survey techniques. http://www.nauticalcharts.noaa.gov/mcd/learnnc_surveytechniques.html

My learning curve has been high as I have tried to understand all the moving variables that need to be taken into account before an accurate map can be made.

Here’s what I am beginning to understand:

  • Starts with referencing benchmarks – both vertical and horizontal (see blog, May 7) to gain a standard of tidal variation (high and low tide can vary by as much as 20 feet) and GPS location.
  • A measurement is made from the ship’s deck to the water surface. The twin sonar beams are located on the bottom of the ship. We know how far it is from the bottom of the ship to the deck – subtracting the deck to the water line gives the distance below the surface the sonar equipment is found at the time of measurement.
  • The chart is marked off in rectangles. A line is marked for the ship to follow. Traveling at 10 knots, the multibeam equipment located on the bottom of the ship pings sound waves and measures how long they take to return from the bottom. A broad swath of ocean bottom can be measured at the same time. These data are transferred to a computer in the plotting lab where the computer archives it and generates visual images as they come in.
  • The speed of sound varies in different water conditions, including temperature and salinity. Making it more complicated, temperature and salinity varies by depth in the water column beneath the ship. To capture these variables, we cast out a Moving Vessel Profiler (MVP) behind the ship while we travel along. The MVP looks like a small torpedo and is affectionately referred to as the fish. Attached is a sensor that reads temperature, conductivity (a measure for salinity), and depth. These data are transferred along a cable bound within the attached line to a computer on board the ship. “Casting” the fish means letting the line out until the fish approaches the bottom of the ocean – or 500 meters of line – whichever comes first. At that point the fish is retrieved. The data acquired as the fish makes its journey is transferred to the Plotting Lab computer.

    The sensor on the "fish" captures temperature, conductivity, and depth data on the water column beneath the ship.

    The sensor on the “fish” captures temperature, conductivity, and depth data on the water column beneath the ship.

  • As the ship moves along the ocean surface it is subjected to constant movement. It pitches up and down from front to back (pitch), rolls side to side (roll), and rises up and down with the ocean swells (heave). As the survey data is collected, heave, roll, and pitch data is captured to allow for adjustments in the sonar data. All of this varies further with the tide level. All these data are captured and fed into the Plotting Lab computer.

    Data from the ship's multibeam sonar comes to the Platting Lab

    Data from the ship’s multibeam sonar comes to the Plotting Lab

  • The ship travels its projected line, turns around and comes back on another.
  • Small boats with similar beams are dispatched to capture the same measurements closer to the shoreline where it is too shallow for the ship (for tomorrow).
  • This continues until the full ocean bottom in our project area is captured.
  • Finally all these data sets are brought together and stored.
  • During the off season, the data sets are utilized to generate the finished nautical charts ending a long, sophisticated process.

Personal Log: Life on the sea

I have to admit the living spaces on board a working ship are a bit tight. My “state room” measures approximately 10’ x 12’ and is shared with a roommate.  In that space are our bunk beds, a sink, desk, and locker closets. I can’t sit up in bed without hitting my head on the bunk above. Shared between two rooms is a bathroom that is only 4’ x 8’ with a head (mariner’s term for a toilet) and shower. All this space rests on a floor that drops with the curve of the ship approximately 10” from one end to the other. The hallways in the ship are narrow and the stairways steep. Everything is bolted or tied to the floor or table to keep them from being tossed about in choppy waters.

While tight, I have yet to hear anyone wish for more. Perhaps the salt that runs in their mariner blood provides the sustenance they need to thrive in these close quarters at sea.

While my shipmates will call the Rainier home for the duration of the research season, I will be on board for only two weeks before I return to the comforts of my own home and spacious bed.  I have to respect these hardy folk for who they are and all they do.

A cozy state room at sea

A cozy state room at sea

A cozy state room at sea - looking toward the door.

A cozy state room at sea – looking toward the door.

The shared "head" offers the comforts of home.

The shared “head” offers the comforts of home.

A porthole window offers a majestic view.

A porthole window offers a majestic view.

Lesley Urasky: Get that fish outta here! The invasive lionfish, June 24, 2012

NOAA Teacher at Sea
Lesley Urasky
Aboard the NOAA ship Pisces
June 16 – June 29, 2012

Mission:  SEAMAP Caribbean Reef Fish Survey
Geographical area of cruise: St. Croix, U.S. Virgin Islands
Date: June 24, 2012

Location:
Latitude: 19.8584
Longitude: -66.4717

Weather Data from the Bridge:

Air Temperature: 29°C (84°F)
Wind Speed:   16 knots (18 mph), Beaufort scale:  4
Wind Direction: from SE
Relative Humidity: 76%
Barometric Pressure:   1,015.3 mb
Surface Water Temperature: 28°C (82°F)

Lionfish in its native habitat. ( Source: National Geographic; Photograph by Wolcott Henry)

Science and Technology Log

One of the species the scientists are continually scanning for in their videos is the appearance of the Lionfish (Pterois volitans/miles); this is one fish they’re hoping not to see.  It is not native to these waters and is what is known as an invasive or exotic  species.

An invasive species is one that is not indigenous (native) to an ecosystem or area.  Many times these organisms are able to exponentially increase their populations because they may have no natural predators, competition for resources, or they may be able to utilize those resources not used by native organisms.  Most invasions are caused by human actions.  This may involve intentional introduction (many invasive plant species were brought in to create a familiar environment or crop/foraging source), accidentally (rats travelling on ships to distant ports), or unintentionally (people releasing pets that they can no longer take care of). Invasive organisms are problematic because:

  • They can reduce natural biodiversity and native species.
    • Push other species to extinction
    • Interbreed, producing hybrids
  • Degrade or change ecosystem functions
  • Economically:
    • They can be expensive to manage
    • Affect locally produced products causing a decline in revenue (decline of honey bees due to a mite infestation which, in turn, decreases pollination rates)

Within its native habitat, the Indo-Pacific region, the Lionfish  (Pterois volitans/miles) is not a problem because that is where they evolved.  It is in the family Family Scorpaenidae (Scorpionfishes). They inhabit reef systems between depths of 10 m – 175 m.  During the day, they generally can be found within crevices along the reef; at night they emerge to forage in deeper waters, feeding upon smaller fish and crustaceans.

Native range of the Lionfish

Lionfish are venomous and when a person is “stung” by the spines on the dorsal fin, they experience extreme pain, nausea, and can have breathing difficulties.  However, a sting is rarely fatal.  Despite the hazards of the spines, Lionfish are a popular aquarium species.  The problem arises when pet owners irresponsibly get rid of the fish in their aquariums.  Instead of giving them away to pet shops, schools, organizations, or other fish enthusiasts, or contacting a local veterinarian about how to humanely dispose of them, they release them into a nearby marine body of water.  It’s important to realize that even the smallest, seemingly isolated act can have such large consequences.  Remember, if one person is doing it, chances are, others are too. The responsibility of owning an organism is also knowing how to manage it; we need to realize how to protect our marine habitats.

This is where the problem in the Atlantic began.  The occurrence of Lionfish was first noticed along the southeastern coast of Florida in 1985.  An invasive species is considered established when a breeding population develops.  Since their establishment in the waters off of Florida, they have rapidly spread throughout the Atlantic as far north as Rhode Island/Massachusetts , throughout the Caribbean, and into the Gulf of Mexico.

Animated map depicting the spread of the Lionfish

While on our cruise every sighting of a Lionfish was cause for further examination.  There was one Lionfish that exhibited a behavior that Kevin Rademacher (Chief Scientist) had never seen before.  The fish was on the bottom and moving himself along instead of freely swimming.  Videos like this are instrumental in helping scientists figure out Lionfish behavior in their “new” environment as well as their interactions with the surrounding organisms and environment.  Hopefully, as this database continues to grow, scientists will develop new understandings of the Lionfish and its effect on the waters of the Atlantic, Caribbean, and Gulf of Mexico.

Divers are encouraged to kill any Lionfish they encounter.  The only safe way to do this is from a distance (remember, their dorsal spines are venomous); usually, this is accomplished by using a spear gun.  The Commander of the Pisces, Peter Fischel,  was doing a final dive off the pier before we left St. Croix.  He saw three Lionfish, speared them, and brought them to the scientific crew for data collection.  These were frozen and placed in a Ziploc back for preservation.  They will be examined back at the lab in Pascagoula, Mississippi.

Three Lionfish caught along the Frederickstad, St. Croix pier. (Notice the 6″ ruler for scale.)

Personal Log

The science portion of the cruise is coming to a close. Today was our last day of sampling.  As with yesterday, no fish were caught by the day crew, so we were able to begin cleaning and packing throughout the day instead of waiting until the end.  A few days after we arrive in Mayport, Florida, the Pisces will be going out on another cruise along the east coast.  On Sunday, July 1st, Joey Salisbury will be arriving in Mayport with a trailer to unload all the scientific equipment and personal gear from this research cruise.

Bandit reel with St. Thomas in the background

In addition to packing, the wet lab and deck have to be cleaned.  This entails scrubbing down the tables, coolers, and rails along the deck where we baited our hooks to remove all the fish “scum” that has accumulated over the past three weeks.  Between the four of us, we were able to make quick work of the job.  There is only one task left for me to do, and that is to take all of our leftover bait, Atlantic Mackerel, and throw it overboard once we are away from the islands.  (The bait has been used over the course of the past two years, and has essentially outlived its freshness.)

Day operations crew on the Pisces Caribbean Reef Fish Survey (left to right: Ariane Frappier, Kevin Rademacher (Chief Scientist), Joey Salisbury, and myself).


I want to thank all the scientists on the day operations crew and the deck hands for making me feel so welcome, being ever so patient as I learned how to bait hook, load the bandit reel, remove otoliths, sex  the fish, and answer every type of question I had.  They’re all amazing people and are passionate about their jobs.  Kevin was not only great at thoroughly answering any and all questions, but anticipated those I might have and brought interesting things to my attention.  Thank you everyone for an amazing experience that I’ll never forget!

Another incredible person that helped make my trip memorable is my roommate, NOAA Operations Officer, Kelly Schill.  She was very welcoming and made me feel immediately at home on the ship.  She gave me a thorough tour and introduced me to the crew.  I interviewed her briefly about her job in the NOAA Corps.

Kelly Schill, Operations Officer aboard the NOAA ship Pisces. (Source: http://www.noaacorps.noaa.gov)

LU: Kelly, what is your job title and what do you do?

KS: I am a Lieutenant junior grade in the NOAA Corps.  The NOAA Corps is one of the 7 uniformed services and I serve as the Operations Officer aboard the NOAA Ship Pisces.

LU: How long have you been working with NOAA?

KS: I have worked for NOAA a total of 4 years; 3 of which were aboard the NOAA Ship Pisces as a NOAA Corps Officer. My first year, I was a physical scientist and developed geospatial visualizations to assist in the generation of navigational warnings and maritime safety information for Dangers to Navigation for the NOAA and contractor surveys.  I assisted NOAA Ship Thomas Jefferson in the field with the acquisition, converting and cleaning of multi-beam and side-scan sonar data.

Aboard the NOAA Ship Pisces, my responsibility is to be the liaison between the ship’s crew and scientific party to ensure the mission is carried out smoothly and efficiently.  A big part of my job is to handle the logistics and transportation, such as project planning and setting up dockage at different ports from Texas to the Caribbean up to Massachusetts. Most importantly, to continue to learn the intricacies of the ship, effectively operate, and practice safe navigation at all times.

LU: What background and skills are necessary for your job?

KS:  A Bachelors Degree of sciences.  You must complete a year of chemistry, physics and calculus.  Geographic information System (GIS) is equally important. To be well-rounded, internships or field research experience is highly recommended.

Kelly Schill showing off the otolith she just extracted from a Red Hind.

LU: What type(s) of training have you been through for your job?

KS: Being in the uniform service, I was sent to Basic Officer Training Course (BOTC) to learn military etiquette, terrestrial and celestial navigation, safety aboard ships, search and rescue, fire prevention, hands on experience in driving small boats up to larger vessels, etc.  Once out of BOTC and on an assigned ship, I was able to attend further training:  hazardous material courses, dive school, rescue swimming, and medical. There are many more opportunities that were offered. I have only touched on a few.

LU: Have you worked on other ships not associated with scientific research?  If so, what was your job and what type of ship was it?

KS: No, all my experiences were on ships regarding scientific research:  NOAA Ship Thomas Jefferson (hydrographic ship) and the NOAA Ship Pisces (fisheries ship).

LU: Does being on a science research ship bring any specific/different expectations than being on another type of merchant ship?

KS: I am unfamiliar with the expectations on a merchant ship.  Generally, the research vessels are used to support studies intended to increase the public’s understanding of the world’s oceans and climate. Research vessels are not set on a point A to point B system. Various operations are conducted from fisheries, bathymetry, oceanographic, to marine mammal data collection.   These various research projects dictate operation area.  Contrary to research vessels, merchant ships usually have a set destination, from point A to point B transporting cargo of one type or another.

LU:  We are in the middle of a huge ocean, and our destination – a specific sampling site – is a pinpoint on a map. What has to be considered to make sure you get to the exact location?

NOAA ship Pisces ECDIS map. This is a nautical map that is updated monthly.

Closeup of navigational maps showing the location of our sampling sites.

KS:  We use a number of tools: ECDIS, Rosepoint, paper charts, GPS, Dynamic Positioning, and of course manual operation. The scientists will provide a location where they want the ship to be for operations to take place. We use all navigational tools to navigate to that position by creating a route, based on a good GPS feed. Navigational tools include: ECDIS (shows an electronic vector chart), Rosepoint (shows an electronic raster chart), and paper charts.  Multiple navigational tools are for redundancy to ensure safe navigation.

All routes are created on the side of safety to avoid collision with shoals, wrecks, land, neighboring ships, platforms, buoys, obstructions, etc. Once, we are close to our sampling station, the ship is set up into the wind or the current (whichever force is stronger), reduce propulsion, turn rudder hard over to one side to assist in the reduction of propulsion and to line up on a heading in favor of wind or current. The bow thruster can assist in turns as well. Depending on how strict the mission is to hold an exact coordinate, the dynamic position is dialed in and activated.  Otherwise, the watch stander will manually control the engine speed, bow thruster, and rudder to maintain position utilizing outside forces, such as wind, swell, wave state, and currents.

The ship’s radar. The yellow objects at the bottom are St. Thomas and its surrounding small islands, while other vessels will appear in green.

LU: Once we reach a site, what do you need to do to maintain that position during the sampling process?

KS: Every ship has its perks and not all are the same in maintaining a position during the sampling process. Our ship has dynamic positioning (DPS) which uses the rudder, propulsion, and a bow thruster simultaneously to hold position. However, just like any software system, it only works as well as the operator.  The parameters have to be just right to accomplish this goal.  Parameters are set up based on wind speed, swells, sea state, and currents.  All must jive for a positive outcome. Our ship works more efficiently facing into the wind or current; whichever force is the strongest. If both are strong, we split the difference. Should either the bow thruster, main engine, or steering fail, the dynamic position will not properly compensate.

Dynamic Positioning System (DPS) screen. This instrument helps hold the ship at a precise location.

Kelly, thanks for the interview as well as being a great role model for women!  Remember, girls, if you want it, go get it!