Sena Norton, July 13, 2004

NOAA Teacher at Sea
Sena Norton
Onboard NOAA Ship Rainier

July 6 – 15, 2004

Mission: Hydrographic Survey
Geographical Area:
Eastern Aleutian Islands, Alaska
Date:
July 13, 2004

Location: At anchor, Popof Strait, Shumagin Is. AK
Latitude: 55 deg 17.9’ N
Longitude: 160 deg 32.13’W
Visibility: 1nm
Direction: 116 deg
Wind Speed: 10 kts
Sea wave height: n/a
Swell wave height: 0-1 ft
Seawater temperature: 10.1 deg C
Sea level pressure: 1011.0 mb
Cloud Cover: 8/8 Fog
Weather: Foggy with drizzle and areas of rain 12.1 deg C (air temp)

Plan of the Day:
Four launches for shoreline verification and continuation of hydro in deeper water.

Science and Technology Log

I learned the process and background concerning shoreline verification. This process ties in nicely with my new understanding of the process of Laser Airborne Bathymetry and how the two connect together. Shoreline verification is a process where a launch surveys to the 4-meter line and in the process correctly locates any targets found close to shore. The launch actually touches the target, at times from multiple sides so that a true GPS tag can be attached to the feature. This process helps the survey crew make better sense of wide swath readings and discern between sonar “fluff” and true features. Sometimes kelp or other objects block the sonar from capturing an accurate image and in the case of larger objects they are required to be “eye ball” verified for all survey areas. Shoreline is also used to double check location of known targets for drift or geologic movement. In the case of these Alaskan waters, the bottom changes yearly and the same can be said for the shoreline. Rocks move, and sand drifts cause sediment build-ups in different areas and underwater features might not have been placed accurately on the chart in the first place. All these factors add in to the need for physical shoreline verification of the survey swaths.

The jet boat launches are able to go almost all the way into shore but are not used until a prop motor launch has already done a through evaluation of the grid. According to the coxswains, shoreline is one of the more nerve-racking operations that they conduct. They are in shallow water trying to find hazards to navigation and they are still asked to safely navigate themselves. At times they are going into pockets almost blind because of the initial survey information being a tad sketchy. After of day of shoreline the coxswain is mentally and physically worn out.

Personal Log

Last night was a fun night on board, a group of crew and corps officers played some board games and let off some steam. This really is a fun crew to be around they are ready to have a good time and I believe they genuinely enjoy each other’s company. (Even if at times I know they drive each other crazy!) I am feeling more a part of the ship now as ever before, everyone is a friendly face and people are interested in what I am doing and what I do on dry land. They are very supportive of teachers and education and that is a boost to my morale because I feel supported in what I am doing here.

I have also enjoyed the time made available by being on board to work with the other TAS and collaborate with lesson ideas and simply “talk” to each other. Many times the one thing that teachers starve for is a chance to really get down and work with their colleagues. We are already planning on linking our classrooms, like Sister Classes for projects, pen pal and even to track the weather on opposite sides of the U.S. An added benefit is that she also just finished her first year of teaching and teaches at the same middle school level and I do. We have our careers in common and seem to have similar ideas on the direction of science education and its benefit to our students. We have completely different experiences as an educator because I teach in public school and she teaches in a small private school, but hearing the experience of the other has put a perspective not only on education but also on my professional/personal goals for the future of my career.

Question of the Day:
What is a “gyro” and why is it used on a ship?

A “gyro” or gyroscopic compass is the ships compass that is always pointed at the North/South axis no matter what the ship is doing in the water. It can be compared to a child’s top in the way that it works. It is important for a ships compass to be oriented in the N/S axis to accurately navigate and find the exact lat/long point. A compass will always point toward magnetic North which is about 1,600 km south of the North Pole (where all the meridians of longitude converge).

Leyf Peirce, July 12, 2004

NOAA Teacher at Sea
Leyf Peirce
Onboard NOAA Ship Rainier

July 6 – 15, 2004

Mission: Hydrographic Survey
Geographical Area:
Eastern Aleutian Islands, Alaska
Date:
July 12, 2004

Time: 18:00
Latitude: N 55°17.29
Longitude: W 160°32.13
Visibility: 2 nm
Wind direction: 115
Wind speed: 12 knots
Sea wave height: 0 – 1 foot
Swell wave height: 1 foot
Sea water temperature: 10.0 °C
Sea level pressure: 1011.0 mb
Air temperature: 12.2 °C
Cloud cover: 8/8

Science and Technology Log

Today we took a field trip to Sand Point, AK, a small fishing town on Popof Island. It also happens to be a base for the TEXIX LADS, Inc. which is a research facility for airborne laser bathymetry. The goal of this research facility is the same as the RAINIER’s: to chart the ocean floor. However, this group gathers data using a laser attached to the bottom of an airplane as opposed to a boat. The advantage of this type of data collection is that coast line depths can be easily taken without the risk of a boat crashing into uncharted rocks. The technology used aboard the plane is similar to the multibeam sonar systems used on the RAINIER, however instead of a multibeam sonar system, a laser is used. This laser has a pulse rate of 990 pulses per second, a depth range of 70 meters dependent on water clarity, a topographic range of 50 meters above sea level and a swath width that can range from 240 meters to 100 meters depending on flight velocity. And, to acquire the data, the plane travels at between 150 and 175 knots!

While this mode of data acquisition is faster than that aboard the RAINIER, it can only accurately acquire data in shallower waters because of light refractions at deeper depths. Therefore, NOAA works in conjunction with this group to survey the ocean bottom in and around Alaska. While the Tenix LADS, Inc. surveys the coast line, and will warn NOAA ships of any bottom features that might protrude in deeper water, the RAINIER charts the deeper waters (between 30 meters and 400 meters). The data will then be collaborated to produce accurate nautical charts.

We also went to the office where the data collected aboard the plane is processed. While I did not get to study the software used, I did notice that the data processing was very similar to that on the RAINIER; both require data processors to go through the data and filter any outlying points before the data can be applied to the nautical charts. The data is also collected according to “mowing the lawn” lines, similar to the RAINIER. However, these lines are along the shore line as well as going about 250 meters onto the coast itself.

Personal Log

Learning about data acquisition aboard a plane was very interesting today! It was also nice to go to land, where we got an excellent coffee at the only café in Sand Point. We also went on a tour of the town, seeing its one school, one restaurant, and one store. The small homes reminded me of those that sprinkle the south-west Swedish coast line— simple homes that beacon stories and the occasional wonderer. I am amazed at the amount of mystery such towns hold while also giving off such a welcoming, cozy feel. The weather today was the opposite, with the first rain we saw bringing larger swells and more fog. I really can’t complain too much, though, for we have been here for almost a week and still hadn’t seen rain until today. It did make for a very interesting small vessel ride to and from the shore!

I spent a lot of time today talking with Sena Norton, the other Teacher At Sea, about lesson plans and ideas for next year. We have both agreed it would be great for our students to establish a line of communication between our classes. In doing this, we can share various projects, such as an on-going weather project that we are planning to start in January—it will be very interesting to gather data in our own regions and then share and compare weather in Oregon and weather in North Carolina. We are also thinking about conducting a lab involving charting, navigation, and depth measurements where we have our classes work together to complete the final navigational chart of a large section. This is such a great opportunity to not only use the data and information gathered aboard the RAINIER, but to also start establishing a connection with another class in another school! I can’t wait to work on these ideas more tomorrow!

Question of the Day:

Given a different type of laser, could accurate data be collected from a plane at depths greater than 30 meters? Would this be a better way to conduct hydrographic research other than using boats?

Leyf Peirce, July 11, 2004

NOAA Teacher at Sea
Leyf Peirce
Onboard NOAA Ship Rainier

July 6 – 15, 2004

Mission: Hydrographic Survey
Geographical Area:
Eastern Aleutian Islands, Alaska
Date:
July 11, 2004

Time: 21:00
Latitude: N 55°17.27
Longitude: W 160°32.16
Visibility: 4 nm
Wind direction: 095
Wind speed: 10 knots
Sea wave height: 0 – 1 foot
Swell wave height: —
Sea water temperature: 10.6 °C
Sea level pressure: 1017.0 mb
Air temperature: 12.8 °C
Cloud cover: 4/8

Science and Technology Log

Today was my second day aboard a launch boat. With SS Foye, ST Taylor, and ENS Samuelson, we continued to follow lines to chart the ocean floor just south of Egg Island. Today we were on launch boat 5, and luckily everything was working great! We were working with the Reson 8101 again. It should be noted that in previous journal entries I have been misnaming some of the equipment used. Today, I finally got the nomenclature correct. Here are the basics:

  1. ELAC multibeam system is used for deep water, with best resolution over 30 meters
  2. There are two shallow water mulitbeam (SWMB) systems:
    1. Reson 8125 is used with a higher frequency and has better resolution in depths of 0 – 30 meters
    2. Reson 8101 is used for “middle depths” of 0 –120 meters (mostly 30 –120 meters)

I also learned a lot more about how to use the software aboard the ship while we are taking data. For the Reson 8125 and Reson 8101, there are three computers aboard the ship that can talk to each other. Two are located in the cabin and one is located on the deck. One computer in the cabin is used primarily to navigate; the old charts are downloaded onto this computer and the lines on which we need to steer the boat (the lines for mowing the lawn) are superimposed on this chart. This computer is not only hooked up to the computer that gathers data, but is also connected to a computer that is mounted on the console so the captain can see where he or she needs to go. The navigational computer in the cabin is also directly hooked up to the other computer in the cabin. This second cabin computer is connected to the actual multibeam echo scanner system that is mounted to the hull of the ship. When instructed to do so, the second cabin computer can record the data from this system. One of the researchers uses the navigational computer to tell the second computer when to start and stop recording the data. Because the second computer is hooked up to the multibeam system, it also is used to control the parameters of this system, including filters, range, frequency of “pings”, and power. There are several different screens within the program used to control all of this, including a profile screen, which actually shows the profile of the ocean floor, a pitch/roll/heave screen to record that the POS/MV (the positioning device also hooked up to this computer that integrates with the data correcting for the gyration of the ship and it’s position), and a control screen. There are several other screens which can be displayed on this computer, however these listed here are the most important to monitor while gathering data. The power of the multibeam system can be monitored and altered according to depth and profile of the floor; if you want the device to “listen to the pings better”, you increase the power, and however, this also decreases resolution. You would want to do this in greater depths. You can also manually control the depth filter for the data. In order to do this, you change the range of the depths the multibeam system is looking for. This in turn changes the width of the footprint left by the data and thus the resolution. By doing this as you gather data, you are eliminating possible outlying points before ever having them recorded and you are allowing for better resolution at shallower depths. This makes the data processing and cleansing easier, yet it requires constant attention and anticipation while gathering data.

While this technology works relatively well in the field, it is still very expensive and time consuming. A possible design project for my students would be to analyze the existing system and brainstorm ideas for improvement. This would even include researching other systems used internationally.

Personal Log

Today was yet another beautiful day once the fog lifted by mid morning. I am still enchanted by the concept of conducting research on a boat all day—it seems like a job I would love to pursue! Not only are you contributing to society, but you get to see wonderful sights—today we saw a bald eagle, lots of puffin, and two sea lions! I cannot help but laugh at the puffin, though. They eat so much and have such little wings and huge hearts that they try with all their might to fly, but they only become air born with the nudge of a wave. And even then they only maintain an altitude of about 6 inches before they crash into another wave. They are both very amusing and very inspiring. I keep thinking that they are thinking “I think I can, I think I can, Never give up!” With so many sights and things going on both on and off the research vessel, I was not at all disappointed when we were radioed that we were going to spend an extra hour collecting data because the weather was so good (slightly chilly, but the sun was out). When we returned I learned how to download the data to the computers aboard the RAINIER, and then I saw the beginning steps for processing this data. I can’t wait to learn more tomorrow!

Question of the Day: A design problem: a gyrocompass is used to determine bearing and relies on electricity (it has an internal electromagnet). The gyrocompass on the bridge looks like this:

Peirce 7-11-04 gyrocompass

Notice that the angles visible here are 70 ° and 90 °, a difference of 20 °. However, this 20 ° difference is spread over what is actually about 100 °. How, then, does the gyrocompass span the full 360 °?

Sena Norton, July 11, 2004

NOAA Teacher at Sea
Sena Norton
Onboard NOAA Ship Rainier

July 6 – 15, 2004

Mission: Hydrographic Survey
Geographical Area:
Eastern Aleutian Islands, Alaska
Date:
July 11, 2004

Location: At anchor Popof Strait, Shumagin Islands, AK
Latitude: 55 deg 17.30’ N
Longitude: 160 deg 32.14’ W
Visibility: 5 nm

15:00

Direction: 110 deg
Wind Speed: 10 kts
Sea wave height: 0-1 ft
Swell wave height: n/a
Seawater temperature: 10.0 deg C
Sea level pressure: 1018.2 mb
Cloud Cover: 5/8
Weather: Fair to Partly cloudy, spots of fog dissipating. 12.12 deg C

Plan of the Day:
Continue the launch survey with 2 boats. In house data cleaning and processing. Meeting with LIDAR tech stationed in Sandpoint.

Science and Technology Log

I personally spoke with a survey technician, Amanda McKinney on board to gather more information on hydrography and the process behind it. There were two main topics that we discussed: Application and history of marine survey, and the math/science behind the techniques.

Application/History

The technology used for marine survey has been improving by leaps and bounds and we are currently using a collection of old and new technology to gather data. Many nautical charts have not been charted for almost 80 years or more and some areas have never been accurately charted at all. The old process was to drag a lead line behind a transiting ship. This process was full of errors because you could never accurately know your depth, even if the length of the line was known; it was drug and therefore skewed the data. Very often a charted depth from these old processes are found to be dangerous wrong. Another mode of survey is the wire drag, where multiple ships drag a wire through the water column. Once a target has been hit, the depth of that underwater target is calculated, but never truly charted accurately. Side scan sonar came around and improved the survey capability, but it too has its drawbacks. Because the “fish” is towed there are many more mathematical corrections that must be made in order to get a reading that is close to the actual target. It does produce wonderfully clear pictures of what is around the “fish” but those images lack depth of field and the sonar cannot read directly below the transmitter. Quite often with side scan images, divers are needed to dive the sight of a possible target to get accurate readings. Multi-beam sonar can be used in conjunction with side scan to better improve the over all picture of the underwater area. Because multi-beam is able to give more accurate readings and the data is complied in 3-D images, surveyors can have both a clear image and precise depth reading all together. It is hoped in the future that there will be new sonar systems that can scan at 480 beams over .25 x .25 deg per beam with 40+ pings per second. The highest level of technology currently used by NOAA is the Reson 8125 (this system is attached to two boats currently) and it sends out 240 beams over 0.5 x 1 deg / beam at 15 pings per second and runs with 455kHz. Remember, that a short pulse (wavelength) will give better vertical resolution and higher frequencies give shorter pulses or wavelengths.

The math required to figure the depth is not very difficult, however in the case of the ocean, the computers must adjust all readings for depth, salinity, temperature and density, which in a way makes the math more difficult if done by hand.

Depth=Speed+ Time/2

Personal Log

I was able to spend some time with the survey tech’s today and got through some of the PowerPoint presentations that are available here on the intranet to educate myself more on the technology and process. I was pleased to see that I can apply some of the simple ideas to my classroom. When I teach certain science skills I will have real life data sets and examples for the kids to analyze. I also hope to get some of the kids excited in the field of sonar and survey, much needs to be done to improve the accuracy and reliability of these systems and the product they produce.

Sunday equals fishing off the fantail in between shifts. We have a resident pack of gulls that have found it much to their benefit to hang out for the halibut leftovers that get tossed overboard or that slip from bait hooks.

I found a whale bone yesterday on Egg Island and had the boat shop guys saw it in half so that both of us TAS’s could bring something back for the classroom. It is not a large chunk, but authentic to say the least. I also gathered some sea sponge that had washed up and a very unique white rock.

I was very surprised to see the people working on a Sunday. No one should ever question the dedication of the folks on board or say that this is an easy job. One of the engineers has not had a day off in two months or more. The ship is something that has to be tended too by her crew and command 24 hours a day 7 days a week. Self-sufficiency comes with some responsibilities!

Question of the Day

Which is better: side scan or multi-beam sonar?

There is not one that is better than the other so much as they can compliment each other to produce and more detailed and accurate product, namely the nautical charts and other products that use the information gathered via the sonar medium.

Leyf Peirce, July 10, 2004

NOAA Teacher at Sea
Leyf Peirce
Onboard NOAA Ship Rainier

July 6 – 15, 2004

Mission: Hydrographic Survey
Geographical Area:
Eastern Aleutian Islands, Alaska
Date:
July 10, 2004

Time: 18:00
Latitude: N 55°17.29
Longitude: W 160°32.13
Visibility: 6 nm
Wind direction: 110
Wind speed: 12 knots
Sea wave height: 0 – 1 foot
Swell wave height: —
Sea water temperature: 10.6 °C
Sea level pressure: 1016.3 mb
Air temperature: 13.3 °C
Cloud cover: 3/8

Science and Technology Log

Today was the first day we launched the survey boats. I was assigned to a boat with SS Foye, ENS Welton, and ENS Samuelson. A very interesting and eventful day, the best way to describe it is with a timeline:

08:00 board 5 boat with SS Foye, ENS Welton, and ENS Samuelson; Lt. Slover (the FOO—Fieldwork Operations Officer) came aboard for about 20 minutes to run tests on the Reson 80101 multibeam echo sounding equipment we are using (soon dropped Lt. Slover back at the Rainier); NOTE: Reson 80101 is used primarily for shallower water, for it has better resolution at depths less than 75 meters

08:45 arrived at our first way point near Halfway Rock; took first cast with the CTD (testing for conductivity, temperature and depth—all things that factor into velocity speed profile) and found an average depth of about 65 meters

09:00 started doing lines (mowing the lawn pattern) around Halfway Rock; after about 3 lines, Lt. Slover called us back in because the data he had taken did not process correctly—the new programs aboard the ship were not working as well as they had thought

11:25 board the RAINIER while FOO checked our equipment; turned out we had to switch to 6 boat—including downloading new maps and figuring out a new system

11:45 board launches 6 boats and sets out for new set of lines at deeper water than the morning; this boat uses the ELAC multibeam systems which are better for deeper waters (up to 400 meters)

12:00 arrived at new line destination (lat: N 55/14/54, long: W 160/27/43) and ate lunch before doing our CTD cast

12:30 conducted first CTD cast, but computer messed up, so had to repeat the cast and got a better reading (average depth = 150 meters) began line pattern

** After a few lines of learning the computer program, SS Foye allowed me to drive the boat for almost the rest of the time—my experience on boats made this part so much fun—especially using the computer imaging as a navigational chart**

17:30 arrived back at RAINIER for dinner

I was truly impressed with the amount of different technology aboard these ships: 5 computer screens, 2 key boards, and a lot of different software programs used to immediately process the information we were gathering. This was also a great change from being on the big ship all day!

Personal Log

This was definitely my favorite day on the ship so far! The fog lifted early this morning to reveal beautiful islands, puffin, sea gulls, kelp, and even a whale! I was able to experience what it is like to have to make computer programs do what you want them to do (any researcher knows this isn’t always easy), and I had to do this on a rocking boat (for all of you “land researchers”, I suggest you trying it once!). SS Foye, ENS Welton, and ENS Samuelson were all extremely helpful and very good at explaining the technology and theory behind what we were doing. I was extremely impressed with how everyone handled various problematic situations. Computers and technology can be very frustrating sometimes, and the crew aboard the boat handled everything optimistically and professionally. SS Foye asked if I ever would consider giving up teaching and join NOAA—after my experience today, I said I would definitely consider it!

Question of the Day:

What is the effect of different densities of water on sound waves?