Emily Whalen: Station 381–Cashes Ledge, May 1, 2015

NOAA Teacher at Sea
Emily Whalen
Aboard NOAA Ship Henry B. Bigelow
April 27 – May 10, 2015

Mission: Spring Bottom Trawl Survey, Leg IV
Geographical Area of Cruise: Gulf of Maine

Date: May 1, 2015

Weather Data from the Bridge:
Winds:  Light and variable
Seas: 1-2ft
Air Temperature:   6.2○ C
Water Temperature:  5.8○ C

Science and Technology Log:

Earlier today I had planned to write about all of the safety features on board the Bigelow and explain how safe they make me feel while I am on board.  However, that was before our first sampling station turned out to be a monster haul!  For most stations I have done so far, it takes about an hour from the time that the net comes back on board to the time that we are cleaning up the wetlab.  At station 381, it took us one minute shy of three hours! So explaining the EEBD and the EPIRB will have to wait so that I can describe the awesome sampling we did at station 381, Cashes Ledge.

This is a screen that shows the boats track around the Gulf of Maine.  The colored lines represent the sea floor as determined by the Olex multibeam.  This information will be stored year after year until we have a complete picture of the sea floor in this area!

This is a screen that shows the boats track around the Gulf of Maine. The colored lines represent the sea floor as determined by the Olex multibeam. This information will be stored year after year until we have a complete picture of the sea floor in this area!

Before I get to describing the actual catch, I want to give you an idea of all of the work that has to be done in the acoustics lab and on the bridge long before the net even gets into the water.

The bridge is the highest enclosed deck on the boat, and it is where the officers work to navigate the ship.  To this end, it is full of nautical charts, screens that give information about the ship’s location and speed, the engine, generators, other ships, radios for communication, weather data and other technical equipment.  After arriving at the latitude and longitude of each sampling station, the officer’s attention turns to the screen that displays information from the Olex Realtime Bathymetry Program, which collects data using a ME70 multibeam sonar device attached to bottom of the hull of the ship .

Traditionally, one of the biggest challenges in trawling has been getting the net caught on the bottom of the ocean.  This is often called getting ‘hung’ and it can happen when the net snags on a big rock, sunken debris, or anything else resting on the sea floor.  The consequences can range from losing a few minutes time working the net free, to tearing or even losing the net. The Olex data is extremely useful because it can essentially paint a picture of the sea floor to ensure that the net doesn’t encounter any obstacles.  Upon arrival at a site, the boat will cruise looking for a clear path that is about a mile long and 300 yards wide.  Only after finding a suitable spot will the net go into the water.

Check out this view of the seafloor.  On the upper half of the screen, there is a dark blue channel that goes between two brightly colored ridges.  That's where we dragged the net and caught all of the fish!

Check out this view of the seafloor. On the upper half of the screen, there is a dark blue channel that goes between two brightly colored ridges. We trawled right between the ridges and caught a lot of really big fish!

The ME70 Multibeam uses sound waves to determine the depth of the ocean at specific points.  It is similar to a simpler, single stream sonar in that it shoots a wave of sound down to the seafloor, waits for it to bounce back up to the ship and then calculates the distance the wave traveled based on the time and the speed of sound through the water, which depends on temperature.  The advantage to using the multibeam is that it shoots out 200 beams of sound at once instead of just one.  This means that with each ‘ping’, or burst of sound energy, we know the depth at many points under the ship instead of just one.  Considering that the multibeam pings at a rate of 2 Hertz to 0.5 Herts, which is once every 0.5 seconds to 2 seconds, that’s a lot of information about the sea floor contour!

This is what the nautical chart for Cashes Ledge looks like. The numbers represent depth in fathoms.  The light blue lines are contour lines.  The places where they are close together represent steep cliffs.  The red line represents the Bigelow’s track. You can see where we trawled as a short jag between the L and the E in the word Ledge

The stations that we sample are randomly selected by a computer program that was written by one of the scientists in the Northeast Fisheries Science Center, who happens to be on board this trip.  Just by chance, station number 381 was on Cashes Ledge, which is an underwater geographical feature that includes jagged cliffs and underwater mountains.  The area has been fished very little because all of the bottom features present many hazards for trawl nets.  In fact, it is currently a protected area, which means the commercial fishing isn’t allowed there.  As a research vessel, we have permission to sample there because we are working to collect data that will provide useful information for stock assessments.

My watch came on duty at noon, at which time the Bigelow was scouting out the bottom and looking for a spot to sample within 1 nautical mile of the latitude and longitude of station 381.  Shortly before 1pm, the CTD dropped and then the net went in the water.  By 1:30, the net was coming back on board the ship, and there was a buzz going around about how big the catch was predicted to be.  As it turns out, the catch was huge!  Once on board, the net empties into the checker, which is usually plenty big enough to hold everything.  This time though, it was overflowing with big, beautiful cod, pollock and haddock.  You can see that one of the deck crew is using a shovel to fill the orange baskets with fish so that they can be taken into the lab and sorted!

You can see the crew working to handling all of the fish we caught at Cashes Ledge.  How many different kinds of fish can you see?

You can see the crew working to handling all of the fish we caught at Cashes Ledge. How many different kinds of fish can you see? Photo by fellow volunteer Joe Warren

 

At this point, I was standing at the conveyor belt, grabbing slippery fish as quickly as I could and sorting them into baskets.  Big haddock, little haddock, big cod, little cod, pollock, pollock, pollock.  As fast as I could sort, the fish kept coming!  Every basket in the lab was full and everyone was working at top speed to process fish so that we could empty the baskets and fill them up with more fish!  One of the things that was interesting to notice was the variation within each species.  When you see pictures of fish, or just a few fish at a time, they don’t look that different.  But looking at so many all at once, I really saw how some have brighter colors, or fatter bodies or bigger spots.  But only for a moment, because the fish just kept coming and coming and coming!

Finally, the fish were sorted and I headed to my station, where TK, the cutter that I have been working with, had already started processing some of the huge pollock that we had caught.  I helped him maneuver them up onto the lengthing board so that he could measure them and take samples, and we fell into a fish-measuring groove that lasted for two hours.  Grab a fish, take the length, print a label and put it on an envelope, slip the otolith into the envelope, examine the stomach contents, repeat.

Cod, pollock and haddock in baskets

Cod, pollock and haddock in baskets waiting to get counted and measured. Photo by Watch Chief Adam Poquette.

Some of you have asked about the fish that we have seen and so here is a list of the species that we saw at just this one site:

  • Pollock
  • Haddock
  • Atlantic wolffish
  • Cod
  • Goosefish
  • Herring
  • Mackerel
  • Alewife
  • Acadian redfish
  • Alligator fish
  • White hake
  • Red hake
  • American plaice
  • Little skate
  • American lobster
  • Sea raven
  • Thorny skate
  • Red deepsea crab

 

 

 

 

I think it’s human nature to try to draw conclusions about what we see and do.  If all we knew about the state of our fish populations was based on the data from this one catch, then we might conclude that there are tons of healthy fish stocks in the sea.  However, I know that this is just one small data point in a literal sea of data points and it cannot be considered independently of the others.  Just because this is data that I was able to see, touch and smell doesn’t give it any more validity than other data that I can only see as a point on a map or numbers on a screen.  Eventually, every measurement and sample will be compiled into reports, and it’s that big picture over a long period of time that will really allow give us a better understanding of the state of affairs in the ocean.

Sunset from the deck of the Henry B. Bigelow

Sunset from the deck of the Henry B. Bigelow

Personal Log

Lunges are a bit more challenging on the rocking deck of a ship!

Lunges are a bit more challenging on the rocking deck of a ship!

It seems like time is passing faster and faster on board the Bigelow.  I have been getting up each morning and doing a Hero’s Journey workout up on the flying bridge.  One of my shipmates let me borrow a book that is about all of the people who have died trying to climb Mount Washington.  Today I did laundry, and to quote Olaf, putting on my warm and clean sweatshirt fresh out of the dryer was like a warm hug!  I am getting to know the crew and learning how they all ended up here, working on a NOAA ship.  It’s tough to believe but a week from today, I will be wrapping up and getting ready to go back to school!

Theresa Paulsen: Preparing to Explore the Ocean Floor, March 9, 2015

NOAA Teacher at Sea
Theresa Paulsen
Preparing to Board NOAA Ship Okeanos Explorer
March 16 – April 3, 2015

Mission:  Caribbean Exploration (Mapping)
Geographical Area of Cruise:  Caribbean Trenches and Seamounts
Date: March 9, 2015

Personal Log

If you could have any super power imaginable, what would it be?  Growing up, my son asked me this question numerous times as we walked our dog.  While he pondered the advantages of flight, invisibility, or spontaneous combustion, my answer was always the same.  I want Aquaman’s powers (but a better looking outfit).  I want to swim underwater without the need for dive gear, seahorses, or gillyweed, to see what few others have seen.  I want to communicate with whales and dolphins to find out what their large brains can teach us about our planet.  While I may not be able to attain superhero status, I can join some real-world adventurers on an amazing vessel equipped to conduct research that will help realize my dream of seeing the unseen depths of the ocean.

Hello, from Northern Wisconsin!  My name is Theresa Paulsen.  I am a high school science teacher in Ashland, WI.  I have been teaching for 17 years while living along the south shore of Lake Superior with my husband and our two children.

My husband, Bryan

My husband, Bryan

Our children, Ben and Laura, paddling the sea caves in the Apostle Islands, N.L.

Our children, Ben and Laura, paddling the sea caves in the Apostle Islands, N.L.

The pristine lake and the rich forests around the region provide the resources that sustain our local communities.  As we work to promote local stewardship in the classroom, we must recognize that the health and welfare of the resources we treasure are connected to the greater global environment which is heavily influenced by the processes that occur in our oceans. The geological processes occurring near our research zone are fascinating.  The North American plate slides passed the Caribbean plate creating the Puerto Rico trench, the deepest part of the Atlantic Ocean.

Bathymetry of the northeast corner of the Caribbean plate. Image courtesy of USGS.

Maps generated by the vessel’s state-of-the-art multibeam sonar on our mission will help geologists learn more about the tectonic activity and potential seismic hazards in the area. (Let’s hope the only rumblings I feel are those caused by the typical mild sea-sickness!)  The maps will also be used by marine biologists and resource managers to investigate and assess unique habitat zones.  Learn more the mission goals here.

My students and I have been checking in on the vessels live video feed periodically as the ship sails from Rhode Island to Puerto Rico, mapping along the way.  I will join the crew in Puerto Rico on the 14th to begin training before the vessel sets sail for the second leg of the mission on the 16th.  Throughout our journey, scientists will use the maps we generate to determine areas that require further investigation with the vessel’s remotely operated vehicle (ROV) on the third leg of the mission.

NOAA Ship Okeanos Explorer with camera sled, Seirios, deployed and below that, IFE’s Little Hercules—a science-class ROV. Credit: Randy Canfield and NOAA.

My goal is to learn as much as I can on this expedition!  There is no better way to motivate students to become life-long learners and scientific thinkers than to show them how exciting real research can be.   Through the NOAA Teacher at Sea program, my students and I will have the rare opportunity to learn first-hand about the science and technology oceanographers use to study fascinating places in the ocean.   I will return to the classroom in April, equipped with lesson ideas and answers to questions about ocean research and careers! Thank you for following me on my journey.  Please post questions or comments.  I will do my best to address them in future posts (although communication aboard the vessel can be tenuous, I am told).  Here is my first question for you:

Lauren Wilmoth: Strange Sea Creatures, October 16, 2014

NOAA Teacher at Sea
Lauren Wilmoth
Aboard NOAA Ship Rainier
October 4 – 17, 2014

Mission: Hydrographic Survey
Geographical area of cruise: Kodiak Island, Alaska
Date: Friday, October 16, 2014

Weather Data from the Bridge
Air Temperature: 7.32 °C
Wind Speed: 9.2 knots
Latitude: 57°44.179′ N
Longitude: 152°27.987′ W

Science and Technology Log

ENS Steve Wall collecting a bottom sample.

ENS Steve Wall collecting a bottom sample.

Wednesday, I went on a launch to do bottom sampling and cross lines.  Wednesday was our last day of data acquisition, so the motto on the POD (Plan of the Day) was “LEAVE NO HOLIDAYS! If in doubt, ping it again!”  Bottom sampling is pretty straight forward.  We drive to designated locations and drop a device that looks a little like a dog poop scooper down into the water after attaching it to a wench.  The device has a mechanism that holds the mouth of it open until it is jarred from hitting the bottom.  When it hits the bottom, it snaps closed and hopefully snatches up some of the sediment from the bottom.  Then, we reel it up with the wench and see what’s inside.

We took 10 bottom samples and most were the same.  We had a fine brown sand in most samples.  Some samples contained bits of shell, so we documented when that was the case.  At one location, we tried for samples three times and every time, we got just water.  This happens sometimes if the sea floor is rocky and the device can’t pick up the rocks.  If you try three times and get no definitive answer, you label the sample as unknown.  Two times we got critters in our samples.  One critter we found was an amphipod most likely.  The second critter was shrimp/krill-like, but I don’t know for sure.  Cross lines are just collecting sonar data in lines that run parallel to the previous data lines.  This gives us a better image and checks the data.

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Survey Tech Christie and Me on our bottom sampling launch.

Amphipod found in bottom sample.

Amphipod found in bottom sample.

Unknown shrimp/krill critter from bottom sample.

Unknown shrimp/krill critter from bottom sample.

 

 

 

 

 

 

 

 

 

 

 

Staff observations at Terror Bay.

Staff observations at Terror Bay.

Thursday, we closed out the tidal station at Terror Bay. This entailed doing staff observations, a tidal gauge leveling check, and then break down everything including completing a dive to remove the orifice.  Since I have already taken part in a tidal gauge leveling check, I was assigned to the staff observations and dive party.  As I mentioned in an earlier post, for staff observations you just record the level of the water by reading a staff every six minutes for three hours.  We did this while on a boat, because the tide was pretty high when we got started, so we wouldn’t be able to read the staff if we were on shore.  Again, the reason we do staff observations is so we can compare our results to what the tidal gauge is recording to make sure the tidal gauge is and has been working properly.

While doing staff observations, I saw a small jellyfish looking creature, but it was different.  It had bilateral symmetry instead of radial symmetry. Bilateral symmetry is what we have, where one side is more or less the same as the other side.  Jellyfish have radial symmetry which means instead of just one possible place you could cut to make two side that are the same, there are multiple places you can cut to make it the same on each side.  Also, the critter was moving by flopping its body from side to side which is nothing like a jellyfish.  I had to figure out what this was!  In between our observations, Jeff, the coxswain, maneuvered the boat so I could scoop this guy into a cup.  Once we finished our staff observations, we headed to the ship.  I asked around and Adam (the FOO) identified my creature.  It’s a hooded nudibranch (Melibe leonina).  Nudibranches are sea slugs that come in a beautiful variety of colors and shapes.

Bilateral versus radial symmetry.

The hooded nudibranch.

The hooded nudibranch.

ENS Wood and ENS DeCastro diving for the orifice.

ENS Wood and ENS DeCastro diving for the orifice.

After a quick return to the ship, we headed back out with a dive team to remove the orifice from underwater. Quick reminder: the orifice was basically a metal tube that air bubbles are pushed out of.  The amount of pressure needed to push out the air bubbles is what tells us the depth of the water. Anyways, the water was crystal clear, so it was really neat, because we could see the divers removing the orifice and orifice tubing.  Also, you could see all sorts of jellyfish and sea stars.  At this point, I released the hooded nudibranch back where I got him from.

Jellyfish!

Jellyfish!

Just as we were wrapping up with everything.  The master diver Katrina asked another diver Chris if he was alright, because he was just floating on his back in the water. He didn’t respond.  It’s another drill! One person called it in on the radio, one of the divers hopped back in the water and checked his vitals, and another person grabbed the backboard. I helped clear the way to pull Chris on board using the backboard, strap him down with the straps, and pull out the oxygen mask. We got him back to the ship where the drill continued and the medical officer took over. It was exciting and fun to take part in this drill.  This was a very unexpected drill for many people, and they acted so professional that I am sure if a real emergency occurred, they would be prepared.

Drill: Saving ENS Wood.

Drill: Saving ENS Wood.

Personal Log

Sadly, this was most likely my last adventure for this trip, because I fly out tomorrow afternoon. This trip has really been a one-of-a-kind experience. I have learned and have a great appreciation for what it takes to make a quality nautical chart. I am excited about bringing all that the Rainier and her crew have taught me back to the classroom to illustrate to students the importance of and the excitement involved in doing science and scientific research. Thank you so much to everyone on board Rainier for keeping me safe, helping me learn, keeping me well fed, and making my adventure awesome!  Also, thank you to all those people in charge of the NOAA Teacher at Sea program who arranged my travel, published my blogs, provided me training, and allowed me to take part in this phenomenal program.  Lastly, thank you to my students, family, and friends for reading my blog, participating in my polls, and asking great questions.

Did You Know? 

1 knot is one nautical mile per hour which is equal to approximately 1.151 miles per hour.

Challenge:

Can you figure out what my unknown shrimp/krill critter is?

Unknown shrimp/krill critter from bottom sample.

Unknown shrimp/krill critter from bottom sample.

 

Lauren Wilmoth: “Wreckish looking rock?” October 15, 2014

NOAA Teacher at Sea
Lauren Wilmoth
Aboard NOAA Ship Rainier
October 4 – 17, 2014

Mission: Hydrographic Survey
Geographical area of cruise: Kodiak Island, Alaska
Date: Wednesday, October 15th, 2014

Weather Data from the Bridge
Air Temperature: 4.4 °C
Wind Speed: 5 knots
Latitude: 57°56.9′ N
Longitude: 153°05.8′ W

Science and Technology Log

Thank you all for the comments you all have made.  It helps me decide what direction to go in for my next post.  One question asked, “How long does it take to map a certain area of sea floor?”  That answer, as I responded, is that it depends on a number of factors including, but not limited to, how deep the water is and how flat the floor is in that area.

To make things easier, the crew uses an Excel spreadsheet with mathematical equations already built-in to determine the approximate amount of time it will take to complete an area.  That answer is a bit abstract though.  I wanted an answer that I could wrap my head around.  The area that we are currently surveying is approximately 25 sq nautical miles, and it will take an estimated 10 days to complete the surveying of this area not including a couple of days for setting up tidal stations.  To put this in perspective, Jefferson City, TN is approximately 4.077 sq nautical miles.  So the area we are currently surveying is more than 6 times bigger than Jefferson City!  We can do a little math to determine it would take about 2 days to survey an area the size of Jefferson City, TN assuming the features are similar to those of the area we are currently surveying.

Try to do the math yourself!  Were you able to figure out how I got 2 or 3 days?

Since we’re talking numbers, Rainier surveyed an area one half the size of Puerto Rico in 2012 and 2013!  We can also look at linear miles.  Linear miles is the distance they traveled while surveying.  It takes into account  all of the lines the ship has completed.  In 2012 and 2013, Rainier surveyed the same amount of linear nautical miles that it would take to go from Newport, Oregon to the South Pole Station and back!

Area we are currently surveying.

Area we are currently surveying (outlined in red) with some depth data we have collected.

Casting a CTD (Conductivity, Temperature, and Depth) gauge.

Casting a CTD (Conductivity, Temperature, and Depth) gauge.

Monday, I went on a launch to collect sonar data.  This is my first time to collect sonar data since I started this journey.  Before we could get started, we had to cast a CTD (Conductivity, Temperature and Depth) instrument.  Sound travels a different velocities in water depending on the salinity, temperature, and pressure (depth), so this instrument is slowly cast down from the boat and measures all of these aspects on its way to the ocean floor.  Sound travels faster when there is higher salinity, temperature, and pressure.  These factors can vary greatly from place to place and season to season.

Imagine how it might be different in the summertime versus the winter.  In the summertime, the snow will be melting from the mountains and glaciers causing a increase in the amount of freshwater.  Freshwater is less dense than saltwater, so it mainly stays on top.  Also, that glacial runoff is often much colder than the water lower in the water column.  Knowing all of this, where do you think sound will travel faster in the summertime?  In the top layer of water or a lower layer of water?  Now you understand why it is so important to cast a CTD to make sure that our sonar data is accurate.  To learn more about how sound travels in water, click here.

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I’m driving the boat.

After casting our CTD, we spent the day running the sonar up and down and up and down the areas that needed to be surveyed.  Again, this is a little like mowing the lawn.  At one point, I was on bow watch.  On bow watch, you sit at the front of the boat and look out for hazards.  Since this area hasn’t been surveyed since before 1939, it is possible that there could be hazards that are not charted.  Also, I worked down in the cabin of the boat with the data acquisition/sonar tuning. Some important things to do below deck including communicating the plan of attack with the coxswain (boat driver), activating the sonar, and adjusting the sonar for the correct depth.  I helped adjust the range of the sonar which basically tells the sonar how long to listen.  If you are in deeper water, you want the sonar to listen longer, because it takes more time for the ping to come back.  I also adjusted the power which controls how loud the sound ping is.  Again, if you are surveying a deeper area, you might want your ping to be a little louder.

Eli working the sonar equipment.

Eli working the sonar equipment.

Tuesday, I helped Survey Tech Christie Rieser and Physical Scientist Fernando Ortiz with night processing.  When the launches come back after acquiring sonar data, someone has to make all that data make sense and apply it to the charts, so we can determine what needs to be completed the following day.  Making sense of the data is what night processing is all about.  First, we converted the raw data into a form that the program for charting (CARIS) can understand.  The computer does the converting, but we have to tell it to do so.  Then, we apply all of the correctors that I spoke about in a previous blog in the following order: POS/MV (Position and Orientation Systems for Marine Vessels) corrector, Tides corrector, and CTD (Conductivity, Temperature, and Depth) corrector.  POS/MV corrects for the rocking of the boat.  For the tides corrector, we use predicted tides for now, and once all the data is collected from our tidal stations, we will add that in as well.  Finally, the CTD corrects for the change in sound velocity due to differences in the water as I discussed above.

After applying all of the correctors, we have the computer use an algorithm (basically a complicated formula) to determine, based on the data, where the sea floor is.  Basically, when you are collecting sonar data there is always going to be some noise (random data that is meaningless) due to reflection, refraction, kelp, fish, and even the sound from the boat.  The algorithm is usually able to recognize this noise and doesn’t include it when calculating the location of the seafloor.  The last step is manually cleaning the data.  This is where you hide the noise, so you can get a better view of the ocean floor.  Also, when you are cleaning, you are double checking the algorithm in a way, because some things that are easy for a human to distinguish as noise may have thrown off the algorithm a bit, so you can manually correct for that. Cleaning the data took the longest amount of time.  It took a couple of hours.  While processing the data, we did notice a possible ship wreck, but the data we have isn’t detailed enough to say whether it’s a shipwreck or a rock.  Senior Tech Jackson noted in the acquisition log that it was “A wreckish looking rock or a rockish looking wreck.”  We are going to have the launches go over that area several more times today to get a more clear picture of is going on at that spot.

H12662_DN195_2804 This is an example of noisy data. In this case, the noise was so great that the algorithm thought the seafloor went down 100 extra meters. Manually cleaning the data can adjust for this so our end product is accurate. The actual seafloor in this case is the relatively straight line at about 100 meters depth.

This is an example of noisy data. In this case, the noise was so great that the algorithm thought the seafloor went down 100 extra meters. Manually cleaning the data can adjust for this so our end product is accurate. The actual seafloor in this case is the relatively straight line at about 100 meters depth.

Personal Log 

Monday was the most spectacular day for wildlife viewing!  First, I saw a bald eagle.  Then, I saw more sea otters.  The most amazing experience of my trip so far happened next.  Orcas were swimming all around us.  They breached (came up for air) less than 6 feet from the boat.  They were so beautiful!  I got some good pictures, too!  As if that wasn’t good enough, we also saw another type of whale from far away.  I could see the blow (spray) from the whale and a dorsal fin, but I am not sure if it is was a Humpback Whale or a Fin Whale.  Too cool!

Bald Eagle Sighting!

Bald Eagle Sighting!

Sea otter

Sea otter

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Orca!

Very close orca!

Very close orca!

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Did You Know? 

Killer whales are technically dolphins, because they are more closely related to other dolphins than they are to whales.

Lauren Wilmoth: Shore Party, October 12, 2014

NOAA Teacher at Sea
Lauren Wilmoth
Aboard NOAA Ship Rainier
October 4 – 17, 2014

Mission: Hydrographic Survey
Geographical area of cruise: Kodiak Island, Alaska
Date: Sunday, October 12, 2014

Weather Data from the Bridge
Air Temperature: 1.92 °C
Wind Speed: 13 knots
Latitude: 58°00.411′ N
Longitude: 153°10.035′ W

Science and Technology Log

The top part of a tidal station.  In the plastic box is a computer and the pressure gauge.

The top part of a tidal station. In the plastic box is a computer and the pressure gauge.

In a previous post, I discussed how the multibeam sonar data has to be corrected for tides, but where does the tide data come from?  Yesterday, I learned first hand where this data comes from.  Rainier‘s crew sets up temporary tidal stations that monitor the tides continuously for at least 30 days.  If we were working somewhere where there were permanent tidal station, we could just use the data from the permanent stations.  For example, the Atlantic coast has many more permanent tidal stations than the places in Alaska where Rainier works.  Since we are in a more remote area, these gauges must be installed before sonar data is collected in an area.

We are returning to an area where the majority of the hydrographic data was collected several weeks ago, so I didn’t get to see a full tidal station install, but I did go with the shore party to determine whether or not the tidal station was still in working condition.

A tidal station consists of several parts: 1) an underwater orifice 2) tube running nitrogen gas to the orifice 3) a nitrogen tank 4) a tidal gauge (pressure sensor and computer to record data) 5) solar panel 6) a satellite antennae.

Let me explain how these things work.  Nitrogen is bubbled into the orifice through the tubing.  The pressure gauge that is located on land in a weatherproof box with a laptop computer is recording how much pressure is required to push those bubbles out of the orifice.  Basically, if the water is deep (high tide) there will be greater water pressure, so it will require more pressure to push bubbles out of the orifice.  Using this pressure measurement, we can determine the level of the tide.  Additionally, the solar panel powers the whole setup, and the satellite antennae transmits the data to the ship.  For more information on the particulars of tidal stations click here

Tidal station set-up.  Drawing courtesy of Katrina Poremba.

Tidal station set-up. Drawing courtesy of Katrina Poremba.

Rainier is in good hands.

Rainier is in good hands.

The tidal station in Terror Bay did need some repairs.  The orifice was still in place which is very good news, because reinstalling the orifice would have required divers.  However, the tidal gauge needed to be replaced.  Some of the equipment was submerged at one point and a bear pooped on the solar panel.  No joke!

After the tidal gauge was installed, we had to confirm that the orifice hadn’t shifted.  To do this, we take manual readings of the tide using a staff that the crew set-up during installation of the tidal station.  To take manual (staff) observations, you just measure and record the water level every 6 minutes.   If the manual (staff) observations match the readings we are getting from the tidal gauge, then the orifice is likely in the correct spot.

Just to be sure that the staff didn’t shift, we also use a level to compare the location of the staff to the location of 5 known tidal benchmarks that were set when the station was being set up as well.  As you can see, accounting for the tides is a complex process with multiple checks and double checks in place.  These checks may seem a bit much, but a lot of shifting and movement can occur in these areas.  Plus, these checks are the best way to ensure our data is accurate.

Micki and Adam setting up the staff, so they can make sure it hasn't moved.

ENS Micki and LTJG Adam setting up the staff, so the surveyor can make sure it hasn’t moved.

Mussels and barnacles on a rock in Terror Bay.

Mussels and barnacles on a rock in Terror Bay.

Leveling to ensure staff and tidal benchmarks haven't moved.

Leveling to ensure staff and tidal benchmarks haven’t moved.

 

 

 

 

 

 

 

 

Today, I went to shore again to a different area called Driver Bay.  This time we were taking down the equipment from a tidal gauge, because Rainier is quickly approaching the end of her 2014 season.  Driver Bay is a beautiful location, but the weather wasn’t quite as pretty as the location.  It snowed on our way in!  Junior Officer Micki Ream who has been doing this for a few years said this was the first time she’d experienced snow while going on a tidal launch.  Because of the wave action, this is a very dynamic area which means it changes a lot.

In fact, the staff that had been originally used to manually measure tides was completely gone, so we just needed to take down the tidal gauges, satellite antenna, solar panels, and orifice tubing.  The orifice itself was to be removed later by a dive team, because it is under water.  After completing the tidal gauge breakdown, we hopped back on the boat for a very bumpy ride back to Rainier.  I got a little water in my boots when I was hopping back aboard the smaller boat, but it wasn’t as cold as I had expected.  Fortunately, the boat has washers and driers.  It looks like tonight will be laundry night.

Raspberry Bay

Driver Bay

Personal Log 

The food here is great!  Last night we had spaghetti and meatballs, and they were phenomenal.  Every morning I get eggs cooked to order.  On top of that, there is dessert for every lunch and dinner!  Don’t judge me if I come back 10 lbs. heavier.  Another cool perk is that we get to see movies that are still in the theaters!  They order two movies a night that we can choose from.  Lastly, I haven’t gotten seasick.  Our transit from Seward to Kodiak was wavy, but I don’t think it was as bad as we were expecting.  The motion sickness medicines did the trick, because I didn’t feel sick at all.

Did You Know? 

NOAA (National Oceanic and Atmospheric Administration) contains several different branches including the National Weather Service which is responsible for forecasting weather and issuing weather alerts.

Animal Spotting

There are sea otters everywhere!

Sea otter (Enhydra lutris) sighting.

Sea otter (Enhydra lutris) sighting.

 

Lauren Wilmoth: Safety First, October 8, 2014

NOAA Teacher at Sea
Lauren Wilmoth
Aboard NOAA Ship Rainier
October 4 – 17, 2014

Mission: Hydrographic Survey
Geographical area of cruise: Kodiak Island, Alaska
Date: Wednesday, October 8, 2014

Weather Data from the Bridge
Air Temperature: 3.82 °C
Wind Speed: 6.1 knots
Latitude: 60°07.098′ N
Longitude: 149°25.711′ W

Science and Technology Log

Junior Officer Micki Ream diving in Thumb's Cove.  Photo courtesy of Junior Officer Katrina Poremba.

Junior Officer Micki Ream diving in Thumb’s Cove. Photo courtesy of Junior Officer Katrina Poremba.

The launch that I participated in on Tuesday was awesome!  We went to an area called Thumb’s Cove.  I thought the divers must be crazy, because of how cold it was.  When they returned to the boat from their dive, they said the water was much warmer than the air.  The water temperature was around 10.5°C or 51°F while the air temperature was hovering right above freezing.  One diver, Katrina, took an underwater camera with her.  They saw jellyfish, sea urchins, and sea stars.

The ride to and from the cove was quite bouncy, but I enjoyed being part of this mini-adventure!  Later that day, we did what is called DC (Damage Control) familiarization.  Basically, we practiced what do in case of an emergency.  We were given a pipe with holes in it and told to patch it with various objects like wooden wedges.  We also practiced using a pump to pump water off of the ship if she were taking on water.  Safety drills are also routine around here.  It’s nice to know that everyone expects the best, but prepares for the worse.  I feel very safe aboard Rainier.

Seastar from Katrina Poremba from the dive at Thumb's Cove.

Sea star and anemones taken by diver Katrina Poremba at Thumb’s Cove.

This source diagram from Kodiak Island shows when the latest data was collected in for an area.  We will be working near the red x.

This source diagram from Kodiak Island shows when the latest data was collected in for an area. We will be working near the red x.

Today, I got a chance to meet with the CO (Commanding Officer), and he explained the navigational charts to me.  Before the ship leaves the port, there must be a navigation plan which shows not only the path the ship will take, but also the estimated time of arrival to various points along the way.  This plan is located on the computer, but also, it must be drawn on a paper chart for backup.

This illustrates again how redundancy, as I discussed in my last blog post, is a very important part of safety on a ship.  Every ship must have up-to-date paper charts on board.  These charts get updated with the information collected from the hydrographic surveys.  The ocean covers more than 70% of our planet which is why Rainier‘s mission of mapping the ocean is so important.  There are many areas in Alaska where the only data on the depth of the water was collected before sonar technology was used.  In fact, some places the data on the charts comes from Captain Cook in the 1700s!  If you look at the chart below the water depth is measured in fathoms.  A fathom is 6 feet deep.  Places that are less than 1 fathom deep have a 05 where the subscript indicates how deep the water is in feet.

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One of the nautical charts that will help Rainier navigate back to its home port in Newport, Oregon. Notice the ocean depth marked in fathoms.

CO (Commanding Officer) and me after discussing nautical charts.

CO (Commanding Officer) and me after discussing nautical charts.

Today, I also spoke with the AFOO (Acting Field Operations Officer), Adam, about some work that he had been doing on Rainier‘s sister ship NOAA Fairweather.  One project they are working on is connecting hydrographic data to fish distribution and abundance mapping.  Basically, they want to find out if it is possible to use sonar data to predict what types of fish and how many you will find in a particular location

They believe this will work, because the sonar produces a back scatter signature that can give you an idea of the sea floor composition (i.e. what it is made of).  For instance, they could tell you if the sea floor is rocky, silty, or sandy using just sonar, as opposed to, manually taking a bottom sample.  If this hydrographic data is integrated with the data collected by other NOAA ships that use trawl nets to survey the fish in an area, this would allow NOAA to manage fisheries more efficiently.  For example, if you have map that tells you that an area is likely to have fish fry (young fish) of a vulnerable species, then NOAA might consider making this a protected area.

Personal Log

Artwork from the SeaLife Center created by high school students to illustrate how much trash ends up on our beaches.

Artwork from the SeaLife Center created by high school students to illustrate how much trash ends up on our beaches.

On Tuesday, I had a little extra time in the afternoon, so I decided to ride my bike down to the Alaska SeaLife Center which is a must-see if you ever find yourself in Seward.  There were Harbor Seals (Phoca vitulina), Stellar Sea Lions (Eumetopias jubatus), Puffins (Genus Fratercula), Pacific Salmon (Genus Oncorhynchus) and much more.  I really appreciated that the SeaLife Center focused on both conservation and on organisms that live in this area.  A local high school even had their art students make an exhibit out of trash found on the beach to highlight the major environmental issue of trash that finds its way to the ocean.

Can you think a project we could do that would highlight a main environmental concern in Eastern Tennessee?  I also thought is was really interesting to see the Puffins dive into the water.  The SeaLife Center exhibit explained about how Puffin bones are more dense than non-sea birds.  These higher density bones are an adaptation that helps them dive deeper.

Puffin at the Alaska SeaLife Center

Puffin at the Alaska SeaLife Center

I officially moved into the ship today.  Prior to that, I was staying at a hotel while they were finishing up repairs.  We are expected to get underway on Friday afternoon.  I am staying in the princess suite!  It is nice and cozy.  I have all of the essentials.  I have a desk, bunk beds, 2 closets, and one bathroom (head).

Rainier, my home for the next week and a half, in Seward Alaska

Rainier, my home for the next week and a half, in Seward, Alaska

My berthing area (where I sleep) nicknamed "The Princess Suite."

My berthing area (where I sleep) nicknamed “The Princess Suite.”

 

Did You Know? 

Junior Officers get homework assignments just like you.  At the navigation briefing today, the CO (Commanding Officer) told the Junior Officers what that they needed to review several documents before going through the inside passage (a particularly tricky area to navigate).  He is expecting them to lead different parts of the next navigation briefing, but he isn’t going to tell them which part they are leading until right before. Therefore, it is important that they know it all!  It’s a little like a pop quiz and presentation in one.

Word of the Day

Bathymetry – the study of the “beds” or “floors” of bodies of water.

Lauren Wilmoth: Introductions, October 7, 2014

NOAA Teacher at Sea
Lauren Wilmoth
Aboard NOAA Ship Rainier
October 4 – 17, 2014

Mission: Hydrographic Survey
Geographical area of cruise: Kodiak Island, Alaska
Date: Tuesday, October 7, 2014

Weather Data from the Bridge
Air Temperature: 0.77 °C
Wind Speed: 12 knots
Latitude: 60°07.098′ N
Longitude: 149°25.711′ W

Science and Technology Log

Our departure from Seward was originally scheduled for today, but the ship is having some repairs done, so our expected departure is now Wednesday or Thursday.  In case you were wondering, this doesn’t delay my return date.  Regardless of the fact that we are not underway, there is still so much to learn and do.

Yesterday, I met with Christie, one of the survey techs, and learned all about the Rainier’s mission.   The main mission of the ship is to update nautical charts.  Up-to-date charts are crucial for safe navigation.  The amount of data collected by Rainier if vast, so although the main mission of the Rainier is updating nautical charts, the data are also sent to other organizations who use the data for a wide variety of purposes.  The data have been used for marine life habitat mapping, sediment distribution, and sea level rise/climate change modeling among other things.  In addition to all of that, Rainier and her crew sometimes find shipwrecks.  In fact, Rainier and her crew have found 5 shipwrecks this season!

 

This is what a shipwreck looks like to the sonar. This is a picture of a shipwreck found by another NOAA hydrographic ship. Photo courtesy of NOAA.

 

Simplified, hydrographic research involves sending multiple sonar (sound) beams to the ocean floor and recording how long it takes for the sound to come back.  You can use a simple formula of distance=velocity/time and divide that by two because the sound has to go to the floor and back to get an idea how deep the ocean is at a particular spot.  This technique would be fine by itself if the water level weren’t constantly fluctuating due to tides, high or low pressure weather systems, as well as, the tilt of the ship on the waves.  Also, the sound travels at different speeds according to the water’s temperature, conductivity and depth.  Because of this, the data must be corrected for all of these factors.  Only with data from all of these aspects can we start to map the ocean floor.  I have attached some pictures of what data would look like before and after correction for tides.

 

This shows the advantages of using multibeam sonar to complete surveys. Photo courtesy of NOAA.

Hydrographic data with correction for tides.  Photo courtesy of Christie.

Hydrographic data with correction for tides. Photo courtesy of Christie.

Hydrographic data without correction for tides.  Photo courtesy of Christie

Hydrographic data without correction for tides. Photo courtesy of Christie

I was also given a tour of the engine room yesterday.  Thanks, William.  He explained to me how the ship was like its own city.  In this city, there is a gym, the mess (where you eat), waste water treatment, a potable (drinkable) water production machine, and two engines that are the same type of engines as train engines.  Many of my students were interested in what happens to our waste when we are aboard the ship.  Does it just get dumped into the ocean?  The answer is no.  Thank goodness!  The waste water is exposed to bacteria that break down the waste  Then, salt water is used to produce chlorine that further sterilizes the waste.  After those two steps, the waste water can be dumped.  The drinking water is created by evaporating the water (but not the salt) from salt water.  The heat for this process is heat produced by the engine.  William also explained that there are two of everything, so if something fails, we’ll still be alright.

Me working out at the Rainier gym.

Rainier’s gym

Rainier's back-up generator.

Rainier’s back-up generator 

Personal Log

Sunday, I drove from Anchorage to Seward.  The drive was so beautiful!  At first, I was surrounded by huge mountains that were vibrant yellow from the trees whose leaves were turning.  Then, there was snow!  It was actually perfect, because the temperature was at just the right point where the snow was melted on the road, but it had blanketed the trees.  Alaska is as beautiful as all of the pictures you see.  The drive should have been about 2.5 hours, but it took me 3.5 hours, because behind each turn the view was better than the previous turn, so I had to stop and take pictures.  I took over 100 pictures on that drive.  Once I arrived in Seward, I was given my first tour of the ship and then I had some time to explore Seward.

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One of the views on my drive from Anchorage to Seward

 

Trying on my survival (gumby) suit

Trying on my survival (gumby) suit

Yesterday (the first official day on the job), I learned so much.  Getting used to the terminology is the hardest part.  There are acronyms from everything!  Immersion is the best way to learn a foreign language, and I have been immersed in the NOAA (National Oceanic and Atmospheric Administration) language.  There is the CO (Commanding Officer), XO (Executive Officer), FOO (Field Operations Officer), TAS (Teacher at Sea or Me!), POD (Plan of the Day) and that is just the tip of the iceberg.  I also had to learn all of the safety procedures.  This involved me getting into my bright red survival suit and learning how to release a lifeboat.

Today, I am going on a dive launch.  The purpose of this launch is to help some of the divers get more experience in the cold Alaskan waters.  I will get to ride on one of the smaller boats and watch as the Junior Officers scuba dive.

Did You Know? 

NOAA Corps is one of the 7 branches of the U.S. uniformed services along with the Army, Navy, Coast Guard, Marine Corps, Air Force, and the Public Health Service Commissioned Corps (PHSCC).