Tag: data collection

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Jennifer Fry, July 17, 2009

NOAA Teacher at Sea
Jennifer Fry
Onboard NOAA Ship Miller Freeman (tracker)
July 14 – 29, 2009 

Mission: 2009 United States/Canada Pacific Hake Acoustic Survey
Geographical area of cruise: North Pacific Ocean from Monterey, CA to British Columbia, CA.
Date: July 17, 2009

Hake are unloaded into holding containers, soon to be weighed and measured
Hake are unloaded into holding containers, soon to be weighed and measured

Weather Data from the Bridge 
Wind speed: 20 knots
Wind direction: 340°from the north- north west
Visibility: foggy
Temperature: 15.2°C (dry bulb); 13.0°C (wet bulb)

Science and Technology Log 

Each day I observe the NOAA scientists using the scientific process.  These are the same process skills we learn in the classroom. The scientists determine what they want to find out and state it in a question form. These are some of the questions/hypotheses that they are trying to answer.

  • What and where are the populations of hake?
  • In what environments do the hake best thrive?
  • When do they migrate?
  • What do they feed on?
  • What feeds on the hake?

Once the hake are observed on the sonar, the trawl net is dropped into the water.  The fish are hauled out onto the deck where they are emptied into huge holding bins.  Scientists want a good sampling of hake for the survey, not too much and not too little.  Getting a good sample is important to the scientists; both for their research and the environment.  The scientists don’t want to take too many hake each time they fish, doing this might diminish the hake population. 

Collecting Data: Observing – Using the senses to collect information.

Classifying – Sorting or ordering objects or ideas into groups or categories based on their properties.

Measuring – Determining dimensions (length/area), volume, mass/weight, or time of objects or events by using instruments that measure these properties.

Otoliths—fish ear bones—are extracted and placed in vials (test tubes) for later study.
Otoliths—fish ear bones—are extracted and placed in vials (test tubes) for later study.

The scientists then collect their data. Fish are separated by species or classified.  All hake collected are then weighed. A certain number of them are measured in length, and their sex is determined.  Scientists observe; dissect a group of hake, and collect the fish’s ear bones, called the otoliths, (2 white oval shapes pictured above). Otoliths are stored in small vials, which are like test tubes, for later study. The test tube has a serial number which is fed into a computer as well. Later, scientists will observe the otoliths under a microscope.  The otolith helps determine the age of the fish. When observed under a microscope, the otolith, or ear bone has rings similar to rings of a tree. The more rings, the older the fish.  The age of the fish or data is then recorded in a computer spreadsheet.

Communicating – Using pictorial, written, or oral language to describe an event, action, or object.

Making Models – Making a pictorial, written or physical representation to explain an idea, event, or object.

Recording Data Writing down the results of an observation of an object or event using pictures, words, or numbers.

As data is collected, it is recorded into a computer database, then scientists create tables and graphs from information in this database.

Inferring  – Making statements about an observation that provide a reasonable explanation.

Predicting – Guessing what the outcome of an event will be based on observations and, usually, prior knowledge of similar events.

Interpreting Data – Creating or using tables, graphs, or diagrams to organize and explain information.

The otoliths look like small oval “winglike” structures.
The otoliths look like small oval “winglike” structures.

Once all the data is in the computer, scientists can analyze or figure out the answers to these questions.

  • What and where are the populations of hake?
  • In what environments do the hake best thrive?
  • When do they migrate?
  • What do they feed on?
  • What feeds on the hake?

Scientists use the data to infer or make a statement about the data that gives a reasonable explanation.  Scientists also make predictions by guessing what the outcome might be based on the data/observations.

Marine Mammal Watch – NOAA Fisheries instructs the scientists to conduct a “marine mammal watch” prior to a fishing trawl. This is to protect the marine mammals, such as dolphins, whales, sea lions, and seals.  When the nets go into the ocean, the curious sea lions want to see what’s going on and play around the nets.  This can prove dangerous for the animals because if they get tangled in the net, they cannot come up for air, and being mammals, they need air.  As it happened, a half a dozen sea lions were spotted around our trawl net. To protect the inquisitive animals we found another spot in which to put our net.

California sea lion
California sea lion

Personal Log 

Everyone aboard the Miller Freeman is a team.  It’s an amazing working environment.  The ship runs like a well oiled machine.  The crew is always so helpful and are dedicated to their work.  The scientists are incredibly dedicated to their specific field and are committed to helping the world and the ocean’s biome. Everyone is so patient with all my questions.  I am so grateful and honored to be part of this hake survey which is so scientifically important in determining the health of our ocean.

Animals Seen Today 
California sea lions
Hake Myctophidae: lantern fish

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Dan Steelquist, July 16, 2009

NOAA Teacher at Sea
Dan Steelquist
Onboard NOAA Ship Rainier
July 6 – 24, 2009 

Mission: Hydrographic Survey
Geographical Area: Pavlov Islands, Gulf of Alaska
Date: July 16, 2009

Weather Data from the Bridge 

Latitude: 55°13.522’ N Longitude: 161°22.795’ W Visibility: 10 Nautical Miles Wind Direction: 174° true Wind Speed: 15 knots Sea Wave Height: 0-1ft. Swell Waves: N/A Water Temperature: 8.3° C Dry Bulb: 10.6° C Wet Bulb: 10.6° C Sea Level Pressure: 1021.0 mb

Science and Technology Log 

The primary mission of the Rainier is to gather hydrographic sounding data. For this leg of the summer field session, that data collection is done by a number of small launches that go out to work each day from Rainier. On a typical day four twenty-nine foot survey launches are deployed from the ship, each with an assigned area to gather data. Each launch is equipped with a multibeam sonar device that sends sound signals to the bottom and then times how long it takes for the signal to return to the receiver.  Knowing how fast the signal will travel through the water, the length of time the signal takes to leave and return to the sounder determines the depth of the water at that point.

Here I am preparing the CTD to take a cast.
Here I am preparing the CTD to take a cast.

For many years sonar devices have only been able to measure the water depth directly below a survey vessel.  Now, with multibeam sonar, survey vessels can cover a larger swath of seafloor with hundreds of depth measurements being taken at a time. Once the data is processed, a “painted” picture of the bottom surface can be generated. Once a launch is in its assigned work area, the sonar is turned on and the boat goes back and forth in a prescribed pattern to gather data on water depth, essentially providing total coverage of what the seafloor looks like in that area. The coxswain (person driving the launch) has a computer screen with a chart of the coverage area and steers the launch over the planned area. As the launch moves along the path of sonar coverage its path shows up on the screen as a different color, letting the driver know where the boat has been.

In order for data to be interpreted accurately, there are many steps in the process from data acquisition to actual placement on a nautical chart. There is one very important piece of data that needs to be gathered in the field as the launches do there work with the sonar. Sound waves can vary in speed as they travel through water, depending on certain conditions. In order for accurate depth readings to be acquired, those conditions must be known. Therefore throughout the data gathering session, hydrographers must acquire data on the condition of the water. That is where a CTD cast comes in. CTD stands for conductivity, temperature, depth. Every few hours a CTD cast must be done in order to accurately interpret the data gathered by the sonar. The device is lowered over this side of the launch and allowed to sink to the bottom. As it descends, the CTD gathers data at various depths. When recovered the CTD is connected to a computer and its data is integrated with the sonar data to acquire more accurate depth readings.

Personal Log 

I’ve been on the Rainier now for twelve days. While there are certain routines on board the ship, there isn’t much routine about the work these people do. I continue to be impressed with how everyone applies their skills to their work in order for data to be gathered. Much of the area where we are working has never been charted before and much of what has been charted was done before World War II with lead lines (dropping a piece of lead attached to a line, and counting the measured marks on the line until it hits bottom). The details acquired by multibeam sonar are truly amazing. We will be here in the Pavlof Islands for a few more days and then head back to Kodiak, where I will get off the ship. Not long to go, but there is still much for me to learn!

Something to Think About 
How long would it take you to paint an entire house with dots from a very small paintbrush? That would be like using a lead line to gather depth information. How long would it take you to paint an entire house with a very small, narrow paint brush? That would be single beam sonar. How much time could you save by using a wide paintbrush? That would be multibeam sonar.

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John Schneider, July 14, 2009

NOAA Teacher at Sea
John Schneider
Onboard NOAA Ship Fairweather 
July 7 – August 8, 2009 

Mission: Hydrographic Survey
Geographical Area: Kodiak, AK to Dutch Harbor, AK
Date: July 14, 2009

Position 
Shumagin Islands

Here I am in the data acquisition chair.
Here I am in the data acquisition chair.

Weather Data from the Bridge 
Weather System: light overcast
Wind: light & variable
Sea State: gentle swells

Science and Technology Log 

Today I spent quite a few hours in the plot room learning about the methods being used on Fairweather for recording bathymetric data. In the picture below and to the right you are looking forward at the starboard side of the Plot Room.  From the left are Chief Survey Tech Lynn Morgan, Survey Tech Dave Franksen, survey crew members Damian Manda and Gabriel Schmidbauer.  Dave is in the chair that I’m occupying in the shot above.

At first, it’s a baffling array of monitors and programs and people.  There are 11 stations for survey personnel in the plot room and it is operating 24/7 when we are under way. In the adjacent compartment are the FOO (Field Operations Officer) and the CST (Chief Survey Technician.)   The FOO on the Fairweather is LT Matt Ringel. The future FOO is LT Briana Welton (who will become the FOO when LT Ringel rotates off the ship); and the CST is Lynn Morgan. While the crew is quite casual in addressing one another, there are three individuals who are addressed by their titles. Commanding Officer Doug Baird is addressed as “CO,” Executive Officer David Zezula is “XO,” and LT Ringel is “FOO.” Everyone else on board is addressed by casual names.  These three officers and the CST are integral to getting our mission accomplished.

More data acquisition!
More data acquisition!

I’ll address the monitors I’m viewing from top to bottom and left to right. Once you’ve sat in the chair it’s not terribly difficult to follow what’s being displayed . . . but a novice like me isn’t able to decode issues that pop up sometimes.  Though I sat a 4hour watch, for the vast majority of that time I had an experienced tech (Will Sauter) very close to help when it was needed. The top right monitor is a closed-circuit TV monitor of the ship’s fantail1 (aft deck.) This is where the remote MVP is deployed from (The MVP is the ship’s equivalent of the CTDs2 we deploy from the launches.)  It’s on the starboard quarter and is deployed with a couple of mouse clicks from the chair. Its mouse is the white one to the right and its keyboard is the white one.

The data acquisition monitors
The data acquisition monitors

To the left of the closed-circuit TV monitor is the control screen for the MVP.  It indicates how deep the “fish” (the sensor) is, the tension on the line, how far behind the ship it is, the GPS accuracy, who is capturing data on the watch and about 20 other parameters.  Whenever something is going that involves the ship or its operations, the bridge must be apprised so the Officer of the Watch is on the same page as the survey and boat teams.  You key the intercom to the bridge and say something like, “Bridge, we’d like a cast, please.”  And they will respond “yes,” “OK,” “affirmative” or something along those lines.  Then we follow with “fish is deployed,” “fish on the bottom” and “fish is back.”  The MVP gets a sound-velocity-in-water throughout the water column.  It can vary by as much as 10 m/s which affects the recorded distance.

The graphic display of the Multi-Beam Echo Sounder called the beam “cone”
The graphic display of the Multi-Beam Echo Sounder called the beam “cone”

The far monitor you see below is a graphic display of the beam-spread from the 8111 Multi-Beam Echo Sounder.  The sounder can cover an angle of 150º (which is 75º to either side of the Nadir3.) Ideally, this line should show blue dots across from one point of the cone to the other.  As you can see, the left side is a bit higher than the right. This could indicate either that the ship is rolling or the bottom is sloped.  The control for adjusting the beam is the left roller ball in the top picture. (The right one is for a different MBES.) The next 3 displays are all controlled with the black keyboard and mouse on the lower shelf in my lap. The left monitor of these three displays technical data about the ship and MBES. One of the devices integrated into the system is an Inertial Motion Sensor which quantifies the amount of roll4, pitch5 and yaw6.

This screen depicts various graphic displays of data.
This screen depicts various graphic displays

Having this information allows the raw data to be corrected for some environmental factors.  Also in the display are accuracy and precision indicators for the GPS positions, personnel on watch, logging verification to begin and cease, and more. The next display is broken into four subordinate windows. On the top left and center are visuals on the nadir beams directly under the ship.  It seemed a bit odd not to simply include the nadir in the bottom half of the display, but the bottom half is processed a bit differently and needs to be segregated. One of the Officers (ENS Patricia Raymond) actually got a screen capture of what appear to be whales directly below the ship. I swear you can identify flukes and fins, but maybe that’s just wishful thinking on my part. I’d have included it here, but there’s just the one copy in plot.  The top right in this display shows a minimized version of the path we’re “mowing.”  You can see the most recent data in green. Finally, on the bottom, are the side-scan views of the bottom. In this particular shot it’s kind of interesting with what appear to be the remains of glacial moraines and scour on the seafloor. 

This display shows technical data about the ship and Multi-Beam Echo Sounder.
This display shows technical data about the
ship and Multi-Beam Echo Sounder.

The last screen, on the far right, is the screen showing our progress on the polygon. The recently scanned area shows up in a different color than those previously scanned and every time you update the plot, the colors begin anew.  Fairweather frequently uses about a 50% overlap to ensure redundancy of data points. On the lower right side of this screen is a graphic of the beams under the ship.  It usually looks very much like the image of the “cone” displayed above. The “70.55” indicates the depth (in S.I. Units of meters) and the top right indicates the status of whether we are logging/retaining the data or if it is just reading it. We don’t log when the ship is turning because the data points get too spread out on the outside of the turn. 

This screen depicts various graphic displays of data.
This screen shows the ship’s progress on the polygon.

Personal Log 

At first glance, it seems that mastering all of this would be daunting, but the ease and confidence that are displayed by the team show that it can be done. Again, the Professional Learning Community idea comes into play as they collectively debug issues and plan for future advancements in the technology even as they are using what is current. Listening to the technical banter and seeing how that much brainpower is focused on a task is really cool. Having spent most of the day in plot, it was real nice to spend the (endless) evening just watching the ocean around me.  When the sun sets at 2315 (11:15 pm) it’s cool.  When it sets at 2313 behind a mountain island off the coast of Alaska it’s unbelievable!

Questions for You to Investigate 

  • How are your inner ears similar to the Inertial Motion detector?
  • How are your semicircular canals contributors to seasickness?

New Terms/Phrases 

  1. Fantail – The aft deck on the ship.  It’s where the majority of overboard work is done
  2. CTD’s – Conductivity/Temperature and Depth sensors
  3. Nadir – The beam that runs the shortest distance to the bottom
  4. Roll – the left/right rocking of the ship
  5. Pitch – the front/back rocking of the ship
  6. Yaw – the swinging of the ship to either side of its course (picture a wagging tail)
Just another day in Paradise!
Just another day in Paradise!
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Jill Stephens, June 28, 2009

NOAA Teacher at Sea
Jill Stephens
Onboard NOAA Vessel Rainier 
June 15 – July 2, 2009 

Mission: Hydrographic Survey
Geographical area of cruise: Pavlov Islands, AK
Date: June 28, 2009

Weather Data from the Bridge 
Position: 55°08.501’N  161°41.073W
Visibility: 10+ nautical miles
Wind: 250° at 12 knots
Pressure: 1024.1 mbar
Temperature: Sea 8.3°C;  Dry bulb 10.0°C;  Wet bulb 7.8°C

The device that collects the information for the Moving Vessel Profiler is referred to as the “fish.”
The device that collects the information for the Moving Vessel Profiler is referred to as the “fish.”

Science and Technology Log 

The day began a bit overcast as Shawn Gendron, Manuel Cruz, Dennis Brooks and I set out in RA 4. Manuel is working on his HIC qualification, so he ended up running the equipment and the boat quite a bit today. The process involved in attaining the Hydrographer in Charge certification takes approximately one year to complete.  To become HIC qualified, you must complete the HIC workbook and demonstrate proficiency in all areas of hydrography covered by NOAA in addition to demonstrating boat handling skills. (I could probably get a few things checked off myself!) Manuel handled the first cast by himself, then allowed me to help with the second cast, and complete the third cast on my own.

The MVP can be controlled with buttons located on a handheld wand. See it my hands?
The MVP can be controlled with buttons located on a handheld wand. See it my hands?

The data retrieved from the casts was good and so there was not a need for any recasts. We have been trying to perform a cast at the beginning, middle and end of the day to provide adequate information regarding depth, temperature, and salinity.  It is also necessary to take casts from various locations within the work area in order to accumulate necessary information to integrate with the raw data from the multi-beam sonar to depict the contour of the sea floor. We were supposed to use the MVP, Moving Vessel Profiler, today instead of the CTD.  When we attempted to start the equipment, an alarm sounded and would not shut down.  The computer also lost communication with the “fish.” (The fish is the data collection device that is placed in the water.) The MVP is similar to the CTD, except that it has a different top and is attached to a cable that extends beyond the stern of the boat.  The MVP collects the same information as a CTD, but instead of a snapshot at selected locations, it can provide continuous depth, conductivity, and temperature readings by automatically taking repeated casts.

After our return to the ship, the MVP system was reviewed by the Field Operations Officer. The operating instructions were reviewed and it was determined that some key steps were not represented correctly.  These omissions were corrected. The launches all have laptops that are being used to convert files from Hypack into Caris. Converting the files on board the launch allows hydrographers and survey technicians the opportunity to review the seafloor surfaces searching for areas of incomplete coverage.  Shawn converted some files and gave me the opportunity to practice cleaning away errant returns or “noise.”

The unit pictured above is one of the two desalination systems for the ship.
The unit pictured above is one of the two desalination systems for the ship.

Personal Log 

Tonight after supper, Mary Patterson, (Teacher at Sea from Texas), and I went on a tour of the engine room with one of the engineers.  I knew that the engines for this ship would be massive, but was unprepared for just how massive they are.  NOAA Ship Rainier was put into commission in 1968 and still has her original engines.  The engineers pride themselves on the excellent maintenance that has enabled the engines to continue to perform well.

All of the ship’s power and freshwater originates in the engine room.  The ship has two generators that can be used to provide electrical power to the entire ship. Electrical outlets, radar, sonar, computers, and lights are among the items that use the power supplied by the generators. Normally, only one of the generators operates at a time and sometimes when in port, the ship is able to connect to shore power and shut down both generators. 

A necessity aboard ship is a continuous supply of potable water.  The ship has two desalination systems located in the engine room.  Sea water is taken into the system under pressure and exposed to heat within the unit.  The evaporated water is collected in trays and sent on to be treated with purification elements.  The salt residue is then returned to the sea.  Each unit has the capacity to produce approximately 150 gallons of fresh water per hour.

Question of the Day 

How does the desalinization technology of 1968 compare to desalinization technology today?

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Candice Autry, August 16, 2006

NOAA Teacher at Sea
Candice Autry
Onboard NOAA Ship Thomas Jefferson
August 7 – 18, 2006

Mission: Hydrographic Survey
Geographical Area: Northwest Atlantic
Date: August 16, 2006

“Experiences on the Fast Rescue Boat” 

TAS Candice Autry prepares to use the CTD instrument which collects water information related to conductivity, temperature, and depth.
Candice Autry prepares to use the CTD instrument which collects water information related to conductivity, temperature, and depth.

Science and Technology Log 

Today I had the opportunity to go out on the Fast Rescue Boat (FRB) to use the conductivity, temperature, depth (CTD) instrument in various places in the harbor.  The CTD looks like a simple white tube; however, the capabilities of the CTD are far from simple!  This devise provides essential data for scientists. Three of us boarded the small FRB, loaded the CTD, and were off to our locations. The first observation noted is that being on the fast rescue boat is a different boating experience compared to the launches and the THOMAS JEFFERSON. The “fast” part of the description is fitting; the boat moves quickly!  The main function of the CTD is to collect data about how the conductivity and temperature of water changes relative to depth. Conductivity and temperature information is important because the concentration of the salt of the seawater can be determined by these two changing variables.

Candice Autry holds the CTD instrument. We collected information from three locations; once in the morning and then again in the afternoon.
Candice Autry holds the CTD instrument. We collected information from three locations; once in the morning and then again in the afternoon.

The CTD devise can also help surveyors determine the speed of sound in the water. The information from the CTD is used in conjunction with multi-beam sonar providing accurate data about the depths of obstructions on the seafloor. The metal frame seen in the picture on the outside of the mechanism is called a rosette.  We attached a rope to the rosette of the CTD, turned it on to collect data, held the devise in the water for two minutes for adjustment, then lowered the instrument down to the bottom of the seafloor. Once the CTD hits the bottom of the seafloor, the rope is pulled back up, the devise is put back into the fast rescue boat, turned off, and it is off to the next location to collect data.  We deployed the CTD in three different locations in the morning and three different locations in the afternoon. At each place where data collection occurred, the location was recorded by using a global positioning system.  Back on the THOMAS JEFFERSON, the information that the CTD collected is downloaded to a computer where specialized software is used to understand the data.

Personal Log 

All of the experiences on the THOMAS JEFFERSON have been interesting and fun.  Tomorrow I will be helping some of the crew on the deck of the ship.  Exposure to saltwater often causes rust to occur; a ship requires constant maintenance!  I am also realizing that this adventure will be over soon, with less than two days left. Until tomorrow…..

A closer view of the CTD.
A closer view of the CTD.
Senior Surveyor Peter Lewit shares the chart used as a guide for the launches to collect data. The red lines in the white area of the chart represent the paths the launches took to collect data using side scan sonar and multi-beam sonar technologies.
Surveyor Peter Lewit shares the chart used to collect data. The red lines in the white area represent the paths the launches took.