Tag: hydrography

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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?

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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 °?

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Sena Norton, July 9, 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 9, 2004

Location: In transit to Shumagin Island collection, due to anchor at NW Egg Island Date: Friday, July 09, 2004
Latitude: N 55 degrees 26.60’
Longitude: W 159 degrees 33.97’
Visibility: <1 mile
Direction: 221 degrees
Wind Speed: 13 kts
Sea wave height: 0-1 ft
Swell wave height: 1-2 ft
Seawater temperature: 10.6 deg C
Sea level pressure: 1016.0 mb
Cloud Cover: 8/8
Weather: 11.7 deg C, fog cover most of the day, some clearing into high cloud cover.

Plan of Day:

1200 stop ship hydro and begin transit to Shumagin Is, specifically Egg Island for anchorage. Anchor set for 2100 or earlier.

Science and Technology Log

The local patch that was being surveyed is too large to finish in one pass. The RAINIER had already done a few lines during their previous legs and on this pass we got about 10- 12 lines surveyed. They will steam back by here to finish the patch at a later date. Tomorrow is set for the first of 5 days of small boat launches and survey. Because I will be aboard a launch I was run through some basic boat safety this afternoon. I was also given an engine room tour and simple explanation and spoke with some crewmembers about standing watch. The XO showed me some books that might be of interest for my curriculum planning and also my general knowledge.

Small Boat Safety and Etiquette

The launches are put in the water around 0800 and will stay out doing survey work till 1600 or so. There will be a complement of people aboard: the coxswain who drives the boat and in charge of safety, three officers from the ship who will run the program and collect data and myself. The launches are stored on the gravity davits along the ship. The boats will be lowered to deck level where the crew will get on board and then the boat is lowered to the water and unhooked. Getting on board the launch you must wear the Mustang survival coat and a hard hat. Nothing is to be in your hands while you board, so all other material need to be near the rail and will be handed over once you are onboard. One of the most dangerous times on the ship are launching and taking up the smaller boats. You are required to wear positive flotation at all times and since the Mustang jacket is bulky and warm, I was issued a float vest. We are launching number 5 and number 3 boats tomorrow.

Standing Watch

While underway there is a rotating watch schedule 4 on, 8 off, 4 on is its most simple explanation. An example watch schedule would be 0800 – 1200 on watch 1200 – 2000 off, 2000 – 2400 on again. So you work 8-12 on both sides of am and pm. Even though the routine is easy to remember it is very difficult on your body and your sleep schedule. The added hardship is the constant light this far north and the pitch black of your berth. For a visitor who has kept a normal sleeping routine you have a different perspective on just what is required for this ship to keep going 24 hours a day. There is a lot more upkeep then I expected and the watch standers are those people. While anchored most people go back to a normal 8 hour work shift, although some of those work shifts are at night there isn’t the constant change.

Engine Room Tour

The engine room tour was loud, even through earplugs and head phone like muffs that roar is amazing. You hear it throughout the ship but nothing compares to the pure sound when you are right next to it. The control room looks out over the two main engines. Each engine turns the port or starboard screw. Control over the engines can be given to the bridge but ultimately if the engineers need to control anything that comes from that area they are all powerful. There is fuel to keep moving to balance out the ships list, fresh water to make, generators to watch so as not to over load any of their out-puts. In a sense the engine room is the heart of the ship. Being self contained completely means that everything has to be running well. This ship even in port generates its own power and while out at sea is capable of making fresh water from salt water. I felt very much at home seeing as I have been in many engine rooms in my life with my father, I plan on going down there a few more times during my time on board.

Question of Day:

How long would it take to survey the entire patch? 8 days going 24 hours/day.

Personal Log

I did a lot of research today from the resources made available to me from the XO. Today was also a day I collaborated with my fellow TAS, something educators rarely get enough time to do. We bounced off a few adaptations of what we have already learned from our time on board. I hope to continue this process throughout my time onboard. No more seasick patch, I think that I am doing well and can handle the rolls. There is some crazy weather on the way too! If it chooses to run up into the Bering Strait we are okay but according to the XO, if the low pressure rides on the south side of the Aleutians it might get sketchy. The RAINIER would have to find a place to hole up and wait for the storm to pass because she is such a small, top-heavy ship. So I might just get a wild Alaskan ship ride after all.

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Leyf Peirce, July 8, 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 8, 2004

Time: 09:00
Latitude: N 55°41.71
Longitude: W 158°03.81
Visibility: < 1 foot
Wind direction: 230
Wind speed: 10 knots
Sea wave height: 0 – 1 feet
Swell wave height: 0 – 2 feet
Sea water temperature: 10.0 °C
Sea level pressure: 1021.3 mb
Air temperature: 10.0 °C
Cloud cover: fog

Science and Technology Log

As I am typing my journal entry, I learn there are several good pictures on the network server of the RAINIER and its crew. Here is just one that I found:

Peirce 7-8-04 Rainier
NOAA Ship RAINIER underway. Credit: NOAA.

From this picture, I can see that the aft most launch ship has been launched for survey, for there are 3 launch boats on either side of the ship. I talked further with the crew today about interesting characteristics of this ship, including a “field trip” with Lt. Kevin Slover to inspect the hulls of the launch boats to see the echo sounding devices. I learned that there are actually 3 different types of these devices: one with low resolution for very deep water, one for a little higher resolution of deep water, and one with high resolution for shallower water. These devices cost up to $25,000! I was able to get pictures of the three types; however I am not able to download them onto the computer yet. Lt. Slover also showed me more of the Caris program, the most recent computer program used to collect and analyze the data. I say most recent used, because these programs are constantly being changed and updated to be more accurate, user-friendlier, and display better graphics. One of the most interesting features of this program is not only its accuracy, but also the ability to look at the computer created images of the ocean floor from any angle. One of the images pulled up as an example showed a shipwreck off of the coast of Seward in about 38 meters of water. The details of this sunken ship were almost crystal clear! Of course, this is after the data has been corrected and cleaned. I hope to work more with this program as we start the launches tomorrow and Saturday.

I also spent some time on the bridge again today. There, I learned a few interesting trivia facts about this ship:

  • The RAINIER was built in 1968 along with 2 other identical ships, the MT. MITCHELL and the FAIRWEATHER, all specifically for NOAA; these three were commissioned in 1969
  • There are 2 main engines aboard this ship, both have 1200 Horsepower and they are the same type of diesel engines as those used in locomotives
  • To figure out the cloud height, one can apply the equation: (wet bulb temp – dry bulb temp)*126.3; there was some dispute on how accurate this is, but for today it works since the wet bulb temperature = dry bulb temperature, so the cloud cover, according to this equation, is at 0 feet which is true since we are in a cloud today with all of this fog
  • The boat was originally built to support 4 launch boats and 2 life rafts, however it was recently modified to have 6 launch boats on it; to counteract this weight up top, more ballast had to be added to the bottom

A launch boat also left today at 08:00 to conduct further hydrographic research, and the RAINIER maintains her course, “mowing the lawn” in a section of uncharted waters between Kodiak and the Shumagin Islands. Once this area is completed, we will head to the Shumagin Islands to anchor and send more launch boats throughout the next week before we return to Kodiak. This is such an adventure!

Personal Log

The foghorn blows every 2 minutes on this ship, and it acts as a great wake up call. This morning, the horn reminds me that we are sailing in a sea of uncharted and now seemingly invisible territory. I feel like an explorer thrown into the time of Captain Cook, half expecting to see a pirate ship emerge from the eerie blanket that surrounds us. However, the multitude of technology aboard this ship flaunts the modern times in which we live and, in doing so, destroys any hope of true exploration of the unknown. Still an explorer at heart, I also still find adventure in what we are doing. We are still conducting hydro research aboard the RAINIER, “mowing the lawn” across uncharted territory, so we are only moving at about 7 knots. A launch boat was also sent out today to investigate near by waters. As I sit here responding to emails and learning even more about how this ship works, I am anxious to see the data that is collected now be processed.

Question for the Day:

In talking with P.S. Shyla Allen and Lt. Kevin Slover, we discussed the rewards of this job—how does this work help society? Both agreed that one of the most rewarding, but somewhat scary, aspects of this job is being able to accurately chart and re-chart high traffic waters. They both said that there are often calls from local fisherman demanding more detailed and more accurate charts. P.S. Allen informed me that there is a group of retired U.S. Coast Guard members that will conduct their own charting research in order to expedite the charting process. While helpful, this is not always the most accurate information. However, I did begin thinking about ways to include local fisherman in the research; to ensure the data that they collect is more accurate. My question for the day is more of an engineering design problem and proposed solution defined:

Problem: Local fishermen travel the coastal waters along Alaska to make a living. However, these waters are poorly charted, if charted at all. As of now, fishermen use a “Hummingbird” device to measure the depth of water where they travel, but there is no electronic device that can record this data accurately, correct this data for margins of error, and combine this data to produce an accurate nautical chart aboard these fishing vessels. While boats such as the RAINIER have this capability, expanding the number of vessels capable of collecting and analyzing such data would expedite the nautical chart updating process.

Proposed Solution: Design, test, and implement a device that abides by the following parameters: not very expensive, accurate, maintains the same abilities as the multibeam echo sounding devices aboard the RAINIER, has the capability of communicating with the computers aboard the RAINIER to share information collected, and can be mounted on the fishing vessels in such a way that it will not alter steering or speed.

I asked Lt. Slover if there is much government funding for such engineering projects, and he assured me there is—most of the U.S.’s imported goods arrive by ship, so more accurate and up to date nautical charts are a large priority.