Nichia Huxtable: Time to Make a Map, May 8, 2016

Sunset XBT deployment off Shimada

NOAA Teacher at Sea

Nichia Huxtable

Aboard NOAA Ship Bell M. Shimada

April 28 – May 9, 2016

Mission: Mapping CINMS
Geographical area of cruise: Channel Islands, California
Date: May 8, 2016
Weather Data from the Bridge:

Science and Technology Log

Seafloor in CINMS
Seafloor in the CINMS

In previous posts, I’ve discussed the ME70 multibeam sonar on board Shimada. You’d think that I’ve told you all there is to know about the wondrous data this piece of equipment provides, but oh, no, dear readers, I’ve merely scraped the surface of that proverbial iceberg. In this post, I will explain how the raw data from the ME70 is used to create important seafloor maps. Heck, I’ll even throw in a shipwreck! Everyone loves shipwrecks.

Nichia Huxtable, Diana Watters, ME70, and EK60; aboard Shimada
Nichia Huxtable, Diana Watters, ME70, and EK60; aboard Shimada

Back to the multibeam. As you may remember, the ME70 uses many beams of sonar to capture a 60 degree image of the water column. It collects A LOT of data, one survey line at a time. Lots of data are good, right? Well, if you want to map the bottom of the ocean, you don’t need ALL the data collected by the ME70, you just need some of it. Take, for example, fish. You don’t want big balls of fish obscuring your view of the seafloor, you just want the seafloor! Leave the schools of fish for Fabio.

Kayla Johnson aboard NOAA Ship Bell M. Shimada
Mapping maven Kayla Johnson

The person you need to make your seafloor map is Kayla Johnson. First, she sends the raw data to a program called MatLab. This nifty software separates the bottom data from all the other stuff in the water column and packages it in something called a .gsf file. Next, this .gsf file goes to this huge processing program called CARIS HIPS, where it is converted into an something called HDCS data.

You’d think that all you’d need to make an accurate seafloor map would be data from the multibeam, but it is actually much more complicated than that (of course you knew that! just look at how long this blog post is). Think about it: while you’re running your survey lines and collecting data, the ocean and, therefore, the ship are MOVING. The ship is heaving, rolling, and pitching, it’s travelling in different directions depending on the survey line, the tides are coming in and out, the temperature and salinity of the water varies, etc. etc. All of these variables affect the data collected by the ME70 and, hence, must be accounted for in the CARIS software. Remember how I said it was HUGE? This is why.

Cross-section of the topography found in the CINMS
Cross-section of the topography found in the CINMS

Everyone still with me? Ok, let’s continue processing this data so that Kayla can make our beautiful map. Next up, she’s going to have to load data into CARIS from the POS. POSMV (POSition of Marine Vehicles) is a software interface used on the ship that collects real-time data on where we are in relation to the water (heave, pitch, and roll).  She’s also going to load into CARIS the local tide information, since the ship will be closer to the seafloor at low tide than at high. Not including tidal change is a good way to get a messed-up map! Once the POSMV and tide files are loaded into CARIS, they are applied to the survey line.

Completed map around San Miguel Island
Completed map around San Miguel Island

Next, Kayla has to compute the TPU (Total Propagated Uncertainty). I could spend the next four paragraphs explaining what it is and how it’s computed, but I really don’t feel like writing it and you probably wouldn’t want to read it. Let’s just say that nothing in life is 100% certain, so the TPU accounts for those little uncertainties.

Since the data was collected using multiple beams at a wide angle, there will be beams returning bad data, especially at the edges of the collection zone. Sometime a bad data point could be a fish, but most often bad data happens when there is an abrupt change in seafloor elevation and the beams can’t find the bottom. So, Kayla will need to manually clean out these bad data points in order to get a clean picture of the seafloor.

Almost done! Last, Kayla makes the surface. All the data points are gridded to a certain resolution based on depth (lots of explanation skipped here…you’re welcome), with the end result being a pretty, pretty picture of the bottom of the seafloor. Phew, we made it! These seafloor maps are incredibly important and have numerous applications, including fisheries management, nautical charting, and searching for missing airplanes and shipwrecks (see! I told you there would be a shipwreck!). I’ll be getting into the importance of this mapping cruise to the Channel Islands Marine Sanctuary in my final post, so stay tuned.

Endnote: A word about XBTs                                                                                                      

Deploying an XBT off Shimada
Deploying an XBT off Shimada

 Before all your data are processed, you need to know how fast the sound waves are travelling through the water. When sound is moving through water, changes in temperature and salinity can bend the wave, altering your data. An XBT is an expendable bathythermograph that is sent overboard every four hours. It transmits temperature and salinity readings throughout its quick trip to the ocean bottom, allowing the computer to make data adjustments, as needed.

 

 

Did You Know?
Hey, you’ve made it to the bottom of this post! If you are interested in seafloor mapping, have I got an institute of higher learning for you. The College of Charleston has a program called BEAMS, which trains future ocean surveyors and includes a course called Bathymetric Mappings. Three of the hip young scientists on board have taken this course and it seems to be pretty amazing. If you love sailing the high seas AND data processing, you might want to check it out.

Nichia Huxtable: Life on board, you won’t be bored!, May 6, 2016

NOAA Teacher at Sea

Nichia Huxtable

Aboard NOAA Ship Bell M. Shimada

April 28-May 9, 2016

Mission: Mapping CINMS                                                                                                           Geographical area of cruise: Channel Islands, California                                                 Date: May 6, 2016

Weather Data from the Bridge: 2-3 ft swells; storm clouds over land, clear at sea

Science and Technology Log

Dismantling the REMUS 600 AUV for its trip home
Goodbye, AUV. Until we meet again.

The AUV is no longer my favorite thing on Shimada. As I write this, it is being dismantled and packed into shipping boxes for its return trip home to Maryland. To keep a long, sad story short, the AUV had a big electrical problem that was fixed, but when the scientists turned it on for a test run, a tiny $6 lithium battery broke open and oozed all over the motherboard. Game over for the AUV. So now my favorite thing on Shimada is the ice cream.

Personal Log

Enough about science and technology for now. I bet you’re really wondering what it’s like day in and day out on board Shimada. Well, my intrepid future NOAA crew members, this blog post is for you! We’ll start what’s most important: the food.

Breakfast, lunch, and dinner are all served at the same time everyday. The food is prepared in the galley and everyone eats in the mess. Beverages, cereal, yogurt, fruit, snacks, the salad bar, and ice cream are available 24 hours a day, so there is no need to ever be hungry. Not all ships are the same, however. In one of the many anecdotes told to me by master storyteller Fabio Campanella, an Italian research ship he once worked on served fresh bread and authentic pizza everyday…sign me up for that cruise!

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Unlike the AUV, the ice cream freezer never disappoints

Next, you’re probably wondering where everyone sleeps. Sleeping quarters are called staterooms and most commonly sleep two people, although larger staterooms might sleep four. Each stateroom has its own television and a bathroom, which is called a head. As you can see in the photo, the bunks have these neat curtains that keep out the light in case your roommate needs to get up at 1 a.m. for the night-shift.

"Working
Working in the Acoustics Lab on Shimada

The Shimada has lots and lots of work and storage rooms, each serving a different function. There is a wet lab, dry lab, chem lab, and acoustics lab for doing SCIENCE (woohoo!), as well as a tech room for the computer specialist (called an ET), storage lockers for paint, cleaning supplies, and linens, plus other rooms full of gear and machinery. There’s also a laundry room, so you can take care of your stinky socks before your roommate starts to complain!

Trash on board is separated into recyclable bottles and cans, food waste, and trash. The food waste is ground up into tiny pieces and dumped in the ocean outside of the sanctuary, while the trash is INCINERATED! That’s right, it’s set on fire…a really, really, hot fire. Ash from the incinerator is disposed of onshore.

"<em
Shimada‘s incinerator

Another important part of the ship is the bridge. Operations occur 24 hours a day, so the ship never sleeps. Officers on the bridge must know what is happening on the ship, what the weather and traffic is like around the ship, and they must make sure to properly pass down this information between watches. The bridge has radar to spot obstacles and other ships, a radio to communicate with other ships, and a radio to communicate with the crew and scientists.

"Looking
Looking for wildlife on the NOAA Ship Bell M. Shimada
"Bride
Bridge on the Shimada

Last, but not least, is the lounge that comes complete with surround-sound, a big screen TV, super-comfy recliners, and about 700 movies, including the newest of the new releases.

"Lounge
Wish this was my living room!

Did you know? 

A female elephant seal was once recorded diving underwater for two continuous hours (they usually stay underwater for 1/2 hour); the deepest recorded dive was by a male and was 5,141ft.

Stay tuned for the next post: Multibeam? You Mean Multi-AWESOME!

Nichia Huxtable: These ARE the Fish You’re Looking For, May 4, 2016

NOAA Teacher at Sea

Nichia Huxtable

Aboard NOAA Ship Bell M. Shimada

April 28 – May 9, 2016

Mission: Mapping CINMS

Geographical area of cruise: Channel Islands, California

Date: May 4, 2016

Weather Data form the Bridge: 0-2ft swells, partly cloudy, slightly hazy

Science and Technology Log:

We’ve been waiting for you, rockfish. We meet again, at last. You might wonder why scientists need to know the location and population densities of rockfish in the Channel Islands National Marine Sanctuary. Well, rockfish are tasty and commercially important, plus they are an important component of healthy marine ecosystems.  To estimate how many there are and where they’re at, you’ll need lots of equipment and fisheries biologist, Fabio Campanella.

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Fabio Campanella and Julia Gorton getting some fresh air. Breaks are important to help them stay on target.

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Monitor showing the EK60 in action. Your eyes can deceive you…watch out for the acoustic dead zone!
First, let’s start with the equipment. Shimada has an EK60, which is essentially a fish finder: the computer’s transducer sends out sonic “pings” that become a single acoustic “beam” in the water. It covers about 7° at one time, so think of it as taking a cross section of the water column. The beam bounces off any solid object in the water and returns to the transducer. The size and composition of the object it hits will affect the quality of the returning pings, which allows Fabio to discern between seafloor, small plankton, and larger fish, as well as their location in the water column. One drawback of this system is the existence of an acoustic dead zone, which is an area extending above the seafloor where fish cannot be detected (think of them as sonar blind spots).

DSC_0956[1].JPG

Do. Or do not. There is no try. Fabio Campanella hard at work in Shimada‘s Acoustic Lab.

 

Starry rockfish (Sebastes constellatus)
It’s a trap! Nope, it’s a starry rockfish (Sebastes constellatus) found in the CINMS.

Ideally, acoustic data collection is done simultaneously with ground truthing data. Ground truthing is a way to verify what you’re seeing. If you think the EK60 is showing you a school of herring, you can run nets or trawls to verify. If it’s in an area that is untrawlable, you can use ROVs or stationary cameras to identify fish species and habitat type. Species distribution maps are also useful to have when determining possible fish species.

 

EK60 data shown on the bottom; ME70 data on top right; 3-D visualization of the school on the top left.
EK60 data shown on the bottom; ME70 data on top right; 3-D visualization of the school on the top left. Witness the power of this fully operational Echoview software.

If Fabio finds something especially interesting on the EK60, such as a large school of fish, he can refer to the data simultaneously collected by the ME70 multibeam sonar to get a more detailed 3-D image. Since the ME70 uses multiple beams and collects 60 degrees of data, he can use it to (usually) get a clear picture of the size and shape of the school, helping him identify fish species and density. So why does he use the EK60 first if there is so much more data provided by the multibeam? Well, the amount of data provided by the ME70 is incredibly overwhelming; it would take weeks of data analysis to cover just a tiny section of the marine sanctuary. By using the EK60 to cover large areas and the ME70 to review small areas of specific interest, he is able to create fish distribution and density maps for the largest areas possible.

After collecting data from the two sonars, it needs to be processed. The method you use to process the data depends on your goal: biomass, population densities, and fish locations are all processed differently. Since rockfish are found close to hard, rocky seafloor, data analysis becomes quite complicated, as it becomes difficult to discriminate the fish from the seafloor. Hard bottoms also introduce a lot of bias to the data; for these, and other, reasons there are very few hard bottom studies for Fabio to refer to.

DSC_0954[1]
Cleaned data. I’ve got a good feeling about this.
But back to the data analysis. Once data is collected, it is loaded into Echoview software. Fabio then removes the background noise coming from other equipment, averages the data to reduce variability, and manually modifies the seafloor line (rocky bottoms with lots of pinnacles give incorrect bottom data). This last step is crucial in this mission because the focus is on rockfish who live close to the bottom.

 

 

DSC_0982[1]
School of fish shown on the right of the screen and the frequency response shown on the left. Fish are not lost today. They are found.
The clean echogram is then filtered for frequencies falling in the suitable range for fish with swimbladders (a gas-filled organ used to control their buoyancy). Object with a flat response at all frequencies (or slightly higher at low frequencies) will most likely be fish with swimbladders, whereas a high response to high frequencies will most likely not be fish (but it could be krill, for example). Once Fabio has made the final fish-only echogram, he exports the backscatter and uses it to create biomass or density estimates. All of these steps are necessary to complete the final product: a map showing where rockfish fish are in relation to the habitat.

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Krill shown on the right and frequency response shown on the left. Judge them by their size, we do.

 

 

 

 

 

 

 

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The final product. When making accurate maps of rockfish, there is no such thing as luck.
Personal Log:

It seems I overpacked sunscreen…12 hours of my day are spent in the acoustics lab staring at monitors, with brief breaks every so often to look for whales and other wildlife. This mission is so technical. I am grateful for the hours spent asking the scientists questions and having them explain the details of their work. Lately, the big screen TV in the lab has been turned on with some great movies playing. So far we’ve watched, Zootopia, Deadpool, LoTR, and, of course, The Force Awakens. May the 4th be with you…always.

Word of the Day: Holiday.

A holiday is an area in your bathymetry map that does not include any data (think of it as “holes in your data”). It’s like you’ve painted a picture, but left a blank splotch on your canvas.

 

Nichia Huxtable: AUV, Why Won’t You Work? May 2, 2016

REMUS 600 onboard Shimada

NOAA Teacher at Sea
Nichia Huxtable
Aboard NOAA Ship Bell M. Shimada
April 28-May 9

Mission: CINMS Mapping
Geographical area of cruise: Channel Islands, California
Date: May 2, 2016

Weather Data from the Bridge: 17-20kt winds; clear skies; 0-1ft swells

Science and Technology Log:

DSC_0746
Preparing the AUV for deployment

There is a lot of amazing equipment on board Shimada, but my favorite, by far, is the REMUS 600 AUV. Really, it should be everyone’s favorite. What other piece of equipment can you release in the middle of the ocean, have it swim around for a few hours collecting data, then have it ready and waiting for you in the morning? I’m pretty sure my laptop wouldn’t be able to do that if I threw it overboard (although, on a few occasions, I’ve been tempted to try).

On Shimada’s mission, the AUV is used when scientists need detailed, high-resolution imaging of deep water areas or areas of special interest. The ship’s ME70 multibeam sonar can map the seafloor up to 350m deep, whereas the AUV can map as far down as 400m. Now remember, this is an AUTONOMOUS Underwater Vehicle; this means that you are literally dropping it off the side of the boat, leaving it to propel itself along a pre-programmed route, then, hours later, returning to a set location with the hope of seeing your million-dollar robot pop back up to the surface to be retrieved.

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The programmed route of the AUV, including satellite and GPS call points (circles) and return location (yellow square)
DSC_0808[1]
The AUV has returned to the Shimada!
 

There is a lot that needs to go right in order for this to happen. In the REMUS 600, there are three separate systems that must all function correctly in order to successfully complete its mission. The navigational system includes an Inertial Measurement Unit (IMU) for pitch, roll, and heading compensation, a Doppler Velocity Log (DVL) for speed over land measurements, GPS for location, and processing software. The communication system includes a micromodem to receive status messages while AUV is up to 1500m away, an Iridium satellite communications system, and, of course, Wi-Fi. The sensors include multibeam sonar, obstacle avoidance sonar, a depth sensor, and a CT (conductivity, temperature) sensor to analyze sound speed for beam formation.

 

Troubleshooting the AUV
Troubleshooting the AUV

If these systems aren’t working correctly, there’s a good chance you’ll never see this AUV again (which would make a lot of people very unhappy). Basically, all these systems ensure that the AUV stays at a specific height above the seafloor (around 75m), runs a specific course that you programmed, and collects data for you to analyze when it returns. Every hour or so while it’s running its course, the AUV rises to the surface, makes a satellite phone call to check in with Shimada, then goes back down to continue its data collection. When it’s done with its course, it runs in circles (think underwater donuts) until the ship returns and the scientists call it back up to the surface where it can be retrieved.

 

DSC_0904[1]
The inner workings of the REMUS 600
Remember how I said that all the systems must be working correctly in order for the AUV to successfully complete its mission? Well, this first launch and retrieval went off without a hitch, but it turns out something went wrong with the data collection (as in, there were no data collected after the first 45 minutes). The scientists are once again on the phone with customer support to try to figure out what went wrong.

 

On the bright side, there are far worse things that could have gone wrong: the AUV successfully ran its course, checked in with the ship, and came up to the surface at the time and place it was supposed to. That doesn’t always happen, which is why the AUV has an “If found, please call this number” sticker right on top of it. Just like what’s written on your retainer case…except your retainer didn’t cost one million dollars.

Personal Log:

Even though it seems like the hours are filled with troubleshooting and problem solving, there are still many things going our way. The ME70 and EK60 have been successfully running all day, the weather is fully cooperating with calm seas and beautiful skies, and, last but not least, dolphins decided to play right next to the ship. Bring on tomorrow!

Dolphins around San Miguel Island
Dolphins around San Miguel Island. Always a crowd pleaser!

Words of the DayAUVs and ROVs. Autonomous Underwater Vehicles are pre-programmed and complete their mission without supervision. Remotely Operated Vehicles are connected to the ship by a cable and are directly controlled by a human operator.

Sarah Raskin: Teacher at Sea Day 6, March 18, 2015

NOAA Teacher at Sea

Sarah Raskin

Aboard NOAA Ship Bell M. Shimada

March 13-18, 2015


Mission: Channel Islands Deep-Sea Coral Study

Geographic Area: Channel Islands, California

Date: March 18, 2015


Day 6: 3/18/15

7th and 8th grade students from Haydock Academy of Arts and Sciences in Oxnard, California, along with elementary students from South Carolina, decorated Styrofoam cups that Peter and I took with us on the Shimada. We brought these cups to show our students the amazing power of underwater pressure.  The depths at which the ROV and CTD Niskin Rosette traveled during the voyage were much further than a human body could physically handle without being in some sort of pressurized submersible.   Human bodies currently experience air pressure when we are at sea level, though we don’t feel the pressure because the fluids in our bodies are pressing outwards with the equal amount of force.  However, once you start traveling underwater, the greater the pressure of the water pushing down on your being.  As one NOAA website states: “For every 33 feet (10.06 meters) you go down, the pressure increases by 14.5 psi. In the deepest ocean, the pressure is equivalent to the weight of an elephant balanced on a postage stamp, or the equivalent of one person trying to support 50 jumbo jets!” (http://oceanservice.noaa.gov/facts/pressure.html)

cups on CTD rosette
Peter and I with the students’ cups tied to the CTD Niskin Rosette

To illustrate how powerful the water pressure is in the deep ocean, Peter and I used Styrofoam cups to demonstrate this concept.  First, we stuffed paper towels into the cups so that they would retain their shapes during a dive down to the bottom of the ocean floor.  Next, we attached the cups to the CTD Niskin rosette. The crew launched the CTD into the ocean and it plunged downwards to a depth of 550 meters. As the cups descended deeper and deeper, the increasing water pressure compressed the air out from between the Styrofoam beads that make up the cup.  What was left was a significantly shrunken version of our cups. Here are the before and after pictures:

cups before dive
The cups before the dive

The CTD Niskin rosette also collected data as it traveled downwards. Water filtered through the machine and sensors gathered information about temperature, salinity, chlorophyll, and dissolved oxygen levels. The tubes on the CTD could also be programmed to collect water samples at certain depths, which they did on the return trip to the surface. This allowed the scientists to collect the water to test for different water quality factors at a later date.

rosette and cups ready to go
The cups and CTD Niskin Rosette prepare to go overboard
reviewing the data
Peter and ST Gunter review the data that is being uploaded from CTD Niskin Rosette during its dive.

Media Day

Today, the scientists and Shimada team were joined by media crews from the LA times and the Santa Barbara Independent, along with some of NOAA’s education outreach specialists. The reporters took a tour around the Shimada and they interviewed the scientists about their important work.  From Peter Etnoyer, and his team’s work on Lophelia and ocean acidification, Branwen Williams’ research on deep-sea coral, Laura Kracker and team’s mapping of uncharted Sanctuary regions, to the MARE team’s innovative ROV technology, the media had quite a bit to report about! 

The reporters were even able to watch the ROV take its final dive of the trip to collect one last acanthogoria sample. One of Branwen’s and Peter’s goals is to be able to determine the ages of these beautiful organisms through the work they do. If they are able to create baseline data for how old an acanthogoria is, based on size and height, then there will be less of a need to collect these specimens in the future. Instead, they will be able to determine age based on looking at the footage during an ROV dive and using the laser measurements on the ROV camera to decide how old the coral is.

Chris Caldow
Chris Caldow, NOAA research coordinator and organizer of our expedition, speaks with the media.
media watching dive
The media crew watches the ROV’s final dive of the trip
Acanthagoria sample
Gathering around the Acanthogoria sample

Until next time….

My journey on the Shimada finally came to a close today. NOAA sent out their local research vessel, the Shearwater, to meet us in the waters off Santa Cruz Island. Many of the scientists, along with the MARE team and myself boarded the Shearwater and watched as the Shimada became smaller and smaller in the distance. It was very sad to say goodbye, but Chris Caldow and the sonar team will continue on the Shimada with their important mapping of the Sanctuary for the next several days.

Shearwater approach
The Shearwater makes its approach to bring us back to shore
Bell M. Shimada
Saying goodbye to the Bell M. Shimada

Our Backyard

Being able to explore the seldom-visited parts of our sanctuary with the scientists and NOAA crew was a once in a lifetime experience. The research these scientists are doing to uncover the hidden depths of the sanctuary is also helping to illustrate how our actions on land have a direct impact on our oceans.

When we learn more about these rarely seen regions of our Sanctuary and about the deep-sea organisms that make their home there, these places and creatures become something that we grow to love and care about. This exploratory research is so important, because as someone on the trip said; “we cannot protect what we don’t know is there.” This is especially relevant for myself and the students from Haydock, because the Channel Islands truly are our backyard; we can see the Islands and Sanctuary from the shores of our city of Oxnard.  When we feel a greater connection to a place such as the Channel Islands National Marine Sanctuary, we are more likely to take part in the stewardship and protection of it for our future generations.

“Treat the earth well: it was not given to you by your parents, it was loaned to you by your children. We do not inherit the Earth from our Ancestors, we borrow it from our Children” (unknown)

To learn more about the Channel Islands National Marine Sanctuary, click on the following link:

http://channelislands.noaa.gov/welcome.html

To learn more about MARE and the ROVs check out their website: http://www.maregroup.org/

For more information about Peter Etnoyer’s work, click the following link:

http://oceanexplorer.noaa.gov/edu/oceanage/03etnoyer/welcome.html

For more information about Branwen Williams work, use the following link:

https://sites.google.com/site/branwenw/home

sunset in Channel Islands NMS
Sunset in the Channel Islands National Marine Sanctuary

Sarah Raskin: Teacher at Sea Day 4, March 16, 2015

NOAA Teacher at Sea

Sarah Raskin

Aboard NOAA Ship Bell M. Shimada

March 13-18, 2015


Mission: Channel Islands Deep-Sea Coral Study

Geographic Area: Channel Islands, California

Date: March 16, 2015

Day 4: Monday 3/16/15

The visiting sonar technician left this afternoon on NOAA’s Shark Cat boat after working diligently to fix the ship’s sonar system throughout the past few days.  As of now, the ME 70 sonar is up and running.  This equals exciting news for the sonar team that has been waiting patiently to begin their projects.  The Shimada actually has two sonar machines; one works with a single beam, while the other, the ME 70 has multiple beams that can cover a much greater amount of territory in the same amount of time.

Shark Cat boat
The Shark Cat alongside the Shimada

How does sonar work?

Sonar technology is a way for us to create images of what is below the surface of the ocean.  The sonar system, which is attached to the bottom of the ship, sends out an acoustic signal towards the ocean floor and then measures how long it takes for the sound to bounce back to the boat. By measuring this, the sonar creates a picture of the depth of the ocean floor in that area.  

Mike and Will
Mike and Will look at data generated from the sonar system

A secondary measurement that is also occurring when the sonar machine is running is called backscatter.  Backscatter measures the intensity, or loudness, of the sound as it echoes back to the ship.  The softer the sound when it reflected back means the softer the type of surface it is bouncing off of, such as sand.  The louder and more severe the sound is equates to a harder surface floor, such as rocky ledges.  As Andy explained to me, think about bouncing a ping-pong ball on a carpet vs. hardwood floor.  The ping-pong ball will have a much stronger bounce off of a hard surface v. a softer one.  Will also explained that based on the backscatter sound we can determine fine details such as whether the sand is fine or coarse.

Simrad ME70
Simrad ME70, Scientific multibeam echo sounder

Both of these sonar features create an image of what the ocean floor looks like, its physical features, habitat types and any potential hazards that may exist below the surface.  This is critical for creating nautical charts and it is also important for the navigation of the ROV, so it doesn’t stumble upon any unexpected obstacles while traveling underwater. 

Shimada seamount
An example of an image created by the sonar system

Another feature that sonar is used for on this ship is to measure fish abundance.  The sound waves travel down and bounce off of the fishes’ swim bladders.  Swim bladders are gas filled bladders found in many fish that helps them stay buoyant.  Using this method, scientists could use sonar to gauge fish populations, instead of catching fish to see what is out there.

An example of an image created by the sonar system
Scientists looking at sonar screens

So far in the trip, Laura Kracker and her team (Mike Annis, Will Sautter and Erin Weller) have been using the working sonar to map fish populations in the area.  Tonight, however, they will use the ME 70 for a test run to map out areas of the Channel Islands National Marine Sanctuary that have never been mapped before!  This data could be used to create brand new nautical maps, to help scientists have a better idea of what the hidden part of our sanctuary looks like and to determine which regions might be best habitats for fish or coral.   Tomorrow, the ROV team will send the ROV to the sites that were mapped the previous night to check out features that were discovered on the seafloor and to explore the newly mapped regions. 

sonar team
The sonar team hard at work (from left Mike, Will, Laura, Erin)

Life at Sea

When setting out on this journey, students asked me what life would be like living on a ship.  I spoke with several of the crew members on the ship about what it is like to be out at sea for days at a time.   So here is an image of what it has been like so far, from the perspective of some of the crew and from my own experiences:

NOAA Ship Bell M. Shimada
The Bell M. Shimada by the Channel Islands

The Bell M. Shimada is an enormous ship, over 200 feet in length.  I have been here for four days now and still have not explored the entire place!  The ship is approx. six stories tall, though on the ship they refer to the different levels as decks, not stories.  The Shimada is run from a platform on the third deck, known as the bridge.  The steering of the ship takes place from the bridge and there is always an assigned lookout person, whose job is to look out the windows to see what is going on around the ship.  The bridge is also equipped with radars that can detect boat traffic or other obstacles.  

A lot of communication goes back and forth between the scientists in the ROV command room and the bridge.  The bridge must ensure that the ship stays steady and follows the ROV during its dive.  If the ship moves too much it can yank the ROV around or the cables from the ROV could get caught or damaged under the ship.  

The Bridge
The Bridge
Andy and CO
Andy shows our Commanding Officer how to operate the ROV

The areas where we sleep on the ship are called staterooms.  Almost all of them consist of bunk beds and have a toilet and shower area.  I am rooming with Erin, one of the scientists working on the sonar mapping project.  Erin and her team work during the night after the ROV runs, so typically she is going to bed shortly before I wake up for the day.  We have both been working hard to stay quiet enough to let each other catch up on our sleep!

stateroom
One of the staterooms

The Shimada has many features that I was not expecting on a ship, such as an exercise room equipped with treadmills and weights.  We even have Internet access here!  Another unexpected feature is the lounge/ theater room that is across the hall from my stateroom.  It has plush reclining chairs, a huge flat screen TV, and all the DVDs you could ever hope to watch, including the newest movies. 

When talking with the crew about what they love most about their jobs, many of them referred to how being part of a NOAA boat allows them incredible travel opportunities.  One person I spoke with has been to 52 different countries throughout his career with NOAA!  Another benefit of a maritime career such as this is that NOAA pays for part of your education.  It requires special schooling and credentials to be able to be an engineer or commanding officer on a ship, and NOAA helps offset those costs.  One of the biggest challenges of the job, however, is being away from family and friends for such long periods of time.  Some of the crew explained to me that they may be out at sea for 30 days at a time, sometimes even longer.

            One great perk to life aboard is the food.  Two chefs prepare all of the meals on the Shimada for us.  Similar to our lunch time at school, the meals are served at the same time each day in what is called the mess hall.  If you oversleep and miss breakfast, not too worry; there is cereal and other snacks available around the clock.  They serve breakfast, lunch and dinner on the ship, and we have even had the treat of fresh salads and homemade desserts! 

stewards
2C Boyd and CS Phillips preparing delicious meals

The ship stays running smoothly thanks to the help of the engineers and crew members.  They work behind the scenes around the clock to keep the ship afloat.

Chief Engineer
Our Chief Engineer
ET and SF
Our Electronics Tech and SF Alves

My absolute favorite location on the ship is called the flying bridge.  It has 3 tall chairs that look out over the ocean and an almost 360 degree view of the sea.  The chairs have been used on previous excursions for scientists to sit and count marine mammals as part of their survey.  It is a great place to watch the sunset from.

view from flying bridge
The view from the flying bridge
sunset
An epic sunset over the Islands

Sarah Raskin: Teacher at Sea Days 2 & 3, March 14-15, 2015

NOAA Teacher at Sea

Sarah Raskin

Aboard NOAA Ship Bell M. Shimada

March 13-18, 2015


Mission: Channel Islands Deep-Sea Coral Study

Geographic Area: Channel Islands, California

Date: March 14-15, 2015


Day 2:  Saturday 3/14/15 

Happy Pi Day everyone!  The second day on the ship was productive and incredible.  The weather was fantastic throughout the entire day, with hardly any wind and a sheet glass ocean.  The stillness of the water made it easy to spot wildlife, and during the day we saw multiple pods of dolphins, sea lions, and a variety of sea birds such as cormorants and brown pelicans.

view from Shimada
A beautiful day aboard the Bell M. Shimada in the Channel Islands National Marine Sanctuary
dolphins
Dolphins swimming alongside the Shimada

The beautiful weather also made for smooth conditions to launch the ROV.  The ROV took three dives today at different locations and depths each time.  Peter and his team picked the locations around the Islands, staying true to spots they had visited in previous years.  Part of their research involves looking at the same coral beds over the course of many years and recording what they observe and noting any changes that may have occurred.  They are observing how the coral, specifically the species Lophelia pertusa, reacts to changes in pH levels and temperature.  This information is important in finding indicators for how our ocean is being affected by warmer temperatures and ocean acidification.

Retrieving the Beagle ROV
Retrieving the Beagle ROV from its first dive of the day
Santa Cruz Island and the ROV
Santa Cruz Island and the ROV

So what exactly is ocean acidification?

As humans, we release carbon dioxide (CO2) into the atmosphere and have been doing so in large quantities since the Industrial Revolution.  Carbon dioxide is released during combustion, when we drive our cars, power our houses and factories, use electricity, burn things, cut down trees, etc. 

The ocean acts as a sponge and absorbs about 30 percent of the carbon dioxide from the atmosphere.  However, as levels of COrise in the atmosphere, so do the levels of CO2 in the ocean.  This is not great news for our ocean or the organisms that make their home there.  When CO2 mixes with seawater, a chemical reaction occurs that causes the pH of the seawater to lower and become more acidic.  This process is called ocean acidification.

Even slight changes in pH levels can have large affects on marine organisms, such as fish and plankton.  Ocean acidification also reduces the amounts of calcium carbonate minerals that are needed by shell-building organisms to build their shells and skeletons.  The damage to these shell-building organisms, including many types of plankton, oysters, coral, and sea urchins, can have a negative ripple effect throughout the entire ocean food web.  An important part of the mission of this trip is to see how ocean acidification is affecting different types of deep-sea coral, such as Lophelia pertusa, that use calcium carbonate minerals to build their skeletons.

pH scale

The scientists and the MARE team conducted three ROV dives throughout the day.  The first dive brought up an outstanding Lophelia sample, and along with it a bizarre deep-sea creature called a basket star.  Basket stars are a type of invertebrate that are related to brittle stars.  Even though they feed mostly on zooplankton, they have long spindly arms that can reach to over a meter in length.   It was astonishing to be able to see this alien looking creature alive and moving!

Day 3: Sunday 3/15/15

After long hours and a late night, the MARE team was able to get the manipulator arm on the ROV up and running, after having technical difficulties with it during the first half of our trip.  This was perfect timing for the first ROV dive of the day in the waters between Santa Cruz and Anacapa Islands.  The goal of this dive was to find scientist Branwen Williams a type coral known as Acanthogorgia.  This coral is incredibly beautiful; tall, fan-like and golden in color.

coral and shark egg case
An Acanthogorgia with a cat shark egg case

Bombs Away:   Branwen hoped to collect samples of this coral to take back to her lab for testing.  She and her team of students and scientists will use these samples to ascertain how old the corals are, how fast they grow and what are they eating.  Branwen explained to me that coral, similar to trees, have growth rings that can be used to determine age as well as other factors.  She mentioned that when looking at age, she looks for the pattern of the “bomb curve” within the coral rings and that provides scientists with a relative date of how old the corals are.  The “bomb curve” is a concentration of radiocarbon (14C) that is found in corals in every ocean in the world.  The concentration of radiocarbon is a direct product of the bomb testing that took place starting in the 1950’s and produced large amounts of this radiocarbon into the atmosphere.  The ocean absorbed that particular type of carbon, and in turn it was absorbed by the corals, who are suspension feeders.  Suspension feeding means that corals eat by stretching their tentacles out to catch tiny particles that are floating by.  So scientists identify the start and peak of the bomb testing in the radiocarbon stored in the coral skeleton to determine growth rates and then the ages of the corals. This was very shocking to me that corals in every ocean have this radiocarbon in their bodies, and clear evidence of how much human actions impact the entire globe.

team looks at samples
The team looks to see what samples have been collected
The Chief Boatswain prepares to operate the winch that will help lift the ROV out of the water
crewmembers
MARE and NOAA crew work together to make sure the ROV makes it back on board safe and sound

Diving Deep:  The ROV was dispatched into the water and soon sunk to around 200 meters.  As it cruised along the ocean floor the team watched as a variety of rockfish scuttled by.  The ROV has two sets of lasers that shoot out in front of it, each spaced 10 centimeters apart.  This gives the scientists an idea of the size of objects or organisms that pass in front of the camera.

The team located the Acanthogorgia habitat and got to work collecting samples using the manipulator arm.  The manipulator arm reminds me of the claw game found in most arcades.  Andy remotely operated the arm, while Dirk worked simultaneously to control the ROV.  Together they were able to collect three exceptional samples, including two Acanthogorgia corals attached to hefty rocks. Each time the manipulator arm reached towards a coral, the whole crew of the Shimada held in their breath in suspense.  Would the arm be able to grasp its target?  The live footage from the ROV is now being streamed throughout the entire ship; in the lounges and staterooms too, so Andy and Dirk had a quite an audience cheering them on!

ROV watch party
Andy and Dirk work the controllers while Peter, Branwen and Leslie watch closely nearby

The samples made it back to the ship safely.  Branwen prepared the coral to take back to the Keck Science Department of the Claremont College where she and her students will conduct their research about this little known species of coral.

Thinking about the effort it takes to research deep-sea coral, involving ROVs and commissioning ships to reach their remote locations, it’s no wonder we know little about them and so much more about their shallow water relatives.

Branwen and coral
Branwen and one of the Acanthogorgia samples
Dirk and Andy coral
Dirk and Andy after a job well done
Chief Survey Tech and ROV
Our Chief Survey Tech waits patiently to assist with the next ROV dive.