NOAA Teacher at Sea
Ginger Redlinger
Onboard NOAA Ship Rainier July 15 – August 1, 2007
Mission: Hydrographic Survey Geographical Area: Baranof Island, Alaska Date: July 29–31, 2007
Weather log on the RAINIER. Data is gathered, then entered into a database.
The RAINIER started its work in South East Alaska in April of this year. Four months and hundreds of nautical miles later it was time to leave: Juneau, Ketchikan, Sitka, Baranof Island, and the Gulf of Esquibel. Three or four research boats were in the water everyday rain or shine, calm or rough water, gathering data. At night, crews’ maintained watch, reviewed data, and planned for the next day’s work. Equipment was checked to ensure everyone’s health and safety. Quality control ensured that the data gathered met NOAA’s expectations. Now it is time to end the Alaskan part of their work and move to their next working location.
While traveling from South Each Alaska to Washington I reflected on the most memorable parts of the journey. I immediately remembered the compliments from pleasure boaters and fishermen about NOAA’s work. Next I thought about the ease at which the crew safely delivered and returned their equipment and crew to and from the ship each day. Then I thought about the NOAA resources I learned about as I studied information about hydrography, technology, satellites, weather, and tides. And how could I not mention the food – it was great. Good food compensates for the sacrifice of being away from home for such a long time.
Water from the Fraser River (green) and the southern end of Georgia Strait waters.
There would be a short break between the end of this voyage and the start of the next, some would remain on the ship, and for others it meant being “at home” for the first time since April. This is part of the sacrifice that mariners, and those who explore the oceans make. As we traveled closer to home many off-duty crewmembers gathered on the fly deck to see home slowly approaching from the distance. They shared stories from the last four months and recalled the moments of laughter on “the big white ship.” After traveling through Canadian waters, around Vancouver Island and into Puget Sound, people began to gather in earnest of the desk. At first I thought it was because we were taking a picture for a “NOAA 200th Anniversary Postcard from the Field,” but many remained on deck. Many were anxious for the first glimpse of their families and their homes. Many of their family members arrived at the Ballard Locks – waving and communicating their excitement about the reunions that would happen in a few short hours.
Mt. Rainier and Seattle in the distance.
The sun is setting as we traveled past the many marinas for all types of marine vessels, houseboats, and dry-docks. As we passed through crewmembers neighborhoods the fading sunlight was replaced with light shining in their eyes as they talked about the view from their windows, their favorite neighborhood haunts, and local treats that mean “home.” As we turn toward the waters that lead to downtown Seattle the crew on the fly deck is silent. The last embers of sunlight are reflecting on the downtown Skyline, it is spectacular. We turn away from downtown and travel through the Fremont Cut. Thank goodness for the navigational skills of this young and talented team – the water traffic from Seattle’s SeaFair was busy. Once we arrived at the NOAA Western Regional Center in Sand Point, CO Noll’s work was done. He had trained his crew to successfully navigate the ship and complete the mission. We are all home; the final navigational command is given.
Rear Admiral De Bow handing the Command Coin to Commander Noll
“All Engines Stop” “All Engines Stop, Aye. – All Engines Stopped” “Very Well.” Rear Admiral De Bow was on board to congratulate him, and pass the time-honored command coin.
I hate to admit it, but like a kid at camp leaving a new set of friends knowing that I most likely will not see many of them again, I feel sadness. The memories and lessons will remain. What a great adventure for a teacher, what a great experience for those who work on the ship, and what a great service provided to those who depend on navigation for commerce, recreation, and those who seek a greater scientific understanding of the earth and how it changes. I can’t wait to share it all with my students and colleagues!!!!
NOAA Teacher at Sea
Ginger Redlinger
Onboard NOAA Ship Rainier July 15 – August 1, 2007
Mission: Hydrographic Survey Geographical Area: Baranof Island, Alaska Date: July 26–27, 2007
Weather Data from the Bridge
Visibility: 10 Nautical Miles
Wind directions: 110°
Wind Speed: 10 Knots
Sea Wave Height: 0-1 feet
Seawater Temperature: 14.4° C
Sea level Pressure: 1012.9 millibars (mb)
Cloud cover: Cloudy
Temperature: 16.7° C, (62° F)
Mariner Word of the Day: Scuttlebutt. A scuttlebutt on an old sailing vessel was the barrel where drinking water was stored. People would gather and talk casually, or gossip, as they drank water. This led to the second definition of scuttlebutt, “a rumor.”
ENS Pereira, Divers-Physical Scientist Campbell and LT Yoos, Coxswain O’Connor review safety checks and dive plan.
Science and Technology Log
We moved the ship from Steamboat Harbor to Bocas de Finas near Bush Top Island because winds were picking up. The ship is safer when it is not anchored in a high wind area! Weather matters a great deal when you are working on the water. Winds contribute to sea waves, swell heights, and can create less-than-ideal conditions for hydrographic surveying. Weather is taken into account in planning when, and where the ship will travel to work. It also determines what should be done first. Specifically, determining the day’s priorities can depend on what time the winds and seas are expected to change. While seaworthy vessels can work effectively in rough waters as is sometimes necessary, knowing when the water will be rough makes for better planning. What I have come to appreciate on this ship is the accuracy of the weather predictions aboard the RAINIER. If the Orders of the Day (OOD) read that it is going to rain – it rains. If it tells me that there will be swells in the afternoon from 3 to 4 feet – there are! Now I don’t know about you, but I have noticed when I am at home the only accurate weather forecast I get is when I look out the window.
Divers begin their descent.
What is it about the weather information that is used on board that makes it so reliable? First, there are many sources of information about the weather that are available, and second, they use them! The Officers on board know a great deal about the earth, from surface to upper atmosphere, so they know what information is necessary for a good analysis. There are many resources available to the RAINIER that you can access too. For example, there are text-based discussions of the weather based on the use of different global models, there are local forecasts, there are infrared satellite maps updated every 30 minutes so you can see where clouds are forming and how they are moving, there are also satellites that collect data in order to show the visibility spectrum, or how much light is available –every 30 minutes. (It tells you the amount of radiant-light energy entering the area.) Another is QuickSCAT that creates a chart of the wind’s movement in an area (with lots of small arrows) so you can see exactly what directions it is moving (wind swirls and moves like water around rocks – it doesn’t just go in one direction all the time!). Lastly, there are grids that tell you the extent of high and low pressure systems, how strong they are, and where they are likely to move. Pressure systems impact the direction of the winds, and their strength.
Sporting Goods – Craig, Alaska
With all of this information, you can take into account many variables that affect navigation: visibility, wind speed and direction, cloud cover, precipitation (which also impacts visibility), water movements, (direction and speed of waves, and swells). I should also add a non-weather related variable that impacts planning – tides. Considering all these variables together helps predict conditions in order to choose the best time of day to complete work, and move vessels through the water SAFELY! As everyone starts their day they know what to expect so they are well prepared.
Website for weather information related to the RAINIER’s work (thanks to CO Noll):
Survey Tech Krynytsky and ENS Villard-Howe (Navigation Officer) gather and examine bottom samples.
Yesterday’s work
Tide Gauge check – Nossuk Bay. We traveled to Nossuk Bay to inspect a Tide Gauge, as it was not sending data correctly. Tide gauge inspections require SCUBA (Self Contained Underwater Breathing Apparatus.) The divers were going to 40 feet below the surface. The pressure is greater underwater every 33 feet, so it is harder to move and to breathe. A specialized crew is sent for this job since it requires specific training in order to execute perfect communication, keen observations, and precise movements of the boat.
After ensuring the underwater section was working properly attention shifted to the land-based components. The crew, except the coxswain, went ashore to inspect the rest of the equipment. Since we noticed fresh bear sign in the area, we talked loudly and kept our eyes open. After everything checked out ok we returned to the ship. I had fifteen minutes to eat lunch and return to the boat for sediment surveys and a run to Craig, AK to pick-up two officers joining the RAINIER for the trip back to Washington. One is a Junior Officer returning to the RAINIER for the trip back to Sand Point. The other is the new Commanding Officer, who will be replacing CO Noll. CO Noll’s commission with the RAINIER ends with the completion of this journey.
Checking the transmission equipment to ensure it is working properly.
We gathered samples from seven different locations where ships and boats anchor when they enter Boca de Finas. Knowing the bottom type can ensure safe anchorage. Not knowing what the bottom is made of when you drop anchor can be dangerous. Surveying the bottom consists of dropping a line with a scoop to the bottom, and examining the contents once the sample is back on board. The contents are compared to a descriptive chart to be sure the correct classification is selected. This information will appear on NOAA charts to help navigators in this area.
Personal Log
The crew jests that the official footwear of Alaskans is a boot called XTRA TUF. When in Craig, we stopped in at the local sporting goods store and I noticed how neatly arranged everything was – with one exception – the boots in the picture below. I asked the man behind the counter about this and he said, “The contents of those boxes will be gone in the next 48 hours – so we don’t bother to mess with them. So I think the crew is correct. At about 10:00 last night, I asked ENS Villard-Howe some questions about ropes, navigation & direction vocabulary. We started to talk about all sorts of nautical topics. She went to her cabin and brought me three very important books – her top three if you want to know anything about maritime topics! The Eldridge Tide and Pilots Book (first written in 1854), American Merchant Seaman’s Manual, and The Ashley Book of Knots. (If anyone wants to get me books for my classroom – these are the three on my wish list! Young potential mariners and marine scientists can learn a great deal from them! )
We talked for another forty-five minutes. As we started to yawn in between sentences we said “enough.” (It wasn’t the company or the topic we were exhausted.) I have to admit, I felt like I was talking with someone who knows and loves the history, knowledge, and skills of her work. She has a true passion for maritime work and her work on the RAINIER.
For my students, I wish them the same level of passion for their endeavors and appreciation for the contributions and history in their yet-to-be chosen field. It is this kind of dedication that makes a great worker, teammate, and leader. There are many examples of this on board – I just happened to spend the later part of the evening exploring the depth of knowledge of one crewmember!
Personal milestone – Sea legs: I ate greasy-yummy pizza on the way back from Craig, AK (a small port town on Prince of Wales Island), while bouncing and rocking across 2-3 foot swells for an hour and it didn’t bother me one bit! : )
Villard-Howe’s top three books.
Question of the Day
Topic 1: What websites can you use to learn about tomorrow’s weather in your area? (Start from the ones that are listed above, and see if you can’t find the links from the SE Alaska sites to your local information.) What information is used to forecast weather in your area? Using the information on the website, try to forecast the weather tomorrow – (temperature, precipitation, general conditions.) See what the “news forecasters” say. Check to see how you did. What would you do different the next time you try to forecast the weather?
Topic 2: How do satellites gather satellite information? How many weather satellite systems are on the NOAA website? Where is the closest NOAA weather station in your area?
Topic 3: What is a Merchant Marine? Where do Merchant Marines work?
NOAA Teacher at Sea
Ginger Redlinger
Onboard NOAA Ship Rainier July 15 – August 1, 2007
Mission: Hydrographic Survey Geographical Area: Baranof Island, Alaska Date: July 23–25, 2007
Weather Data from the Bridge
Visibility: 10 Nautical Miles
Wind directions: 150°
Wind Speed: 10 Knots
Sea Wave Height: none
Seawater Temperature: 14.4° C
Sea level Pressure: 1015.9 millibars (mb)
Temperature: 15.5° C
Mariner Word of the Day: Geodesy
Geodesy is the science of measuring and monitoring the size and shape of the Earth and the location of points on its surface.
Survey Tech Boles holds a Navigational Chart developed by NOAA that also includes Hydrographic survey data
Science and Technology Log: Charts vs. Maps
The RAINIER returned to the Gulf of Esquibel to gather a few more swaths of data to complete their survey of this area. The ship is anchored in Steamboat Bay and several boats are out gathering data around the shoals in the area to identify navigational hazards. Tomorrow I will be on one of those boats – I can’t wait!
Since I am on the ship today, I can tackle a bigger question in my journal entry. This question popped into my head (it didn’t hurt : ) when I was talking with the data processing crew. I want to know what the difference is between charts and maps? Based on the attention to detail that the RAINIER pays to the collection and quality of data to put into their charts I knew it had to be very different from maps! I am figuring there is a clear distinction that is important for everyone to know since we all use maps at some point for driving, cycling, hiking, or boating. I will begin to tackle this question now, but a fuller, more rigorous explanation will evolve as I develop lessons to support this TAS assignment! Let’s start with some basic information:
What is the difference between a chart and a map?
Charts
Has special unique characteristics including a very detailed and accurate representation of the coastline, which takes into account varying tidal levels and water forms, critical to a navigator.
is a working document used to plot courses for navigators to follow in order to transit a certain area It takes into account special conditions required for one’s vessel, such as draft, bottom clearance, wrecks and obstructions which can be hazardous. Way points are identified to indicate relative position and points at which specific maneuver such as changing courses, must be performed.
provide detailed information on the area beneath the water surface, normally not visible to the naked eye, which can and is very critical for the safe and efficient navigation.
Maps
emphasize landforms, including the representation of relief, with shoreline represented as an approximate delineation usually at mean sea level.
is a static document, which serves as a reference guide. A map is not, and cannot be used to plot a course. Rather it provides a predetermined course, usually a road, path, etc., to be followed. Special consideration for the type of vehicle is rarely a consideration. Further, maps provide predetermined points-road intersections-to allow one a choice to change to another predetermined direction.
merely indicate a surface path providing no information of the condition of the road. For instance a map will not provide information on whether the road is under repair (except when it is a new road) or how many potholes or other obstructions it may contain. However the driver is able to make a visual assessment of such conditions.
Source of the above information? You guessed it – NOAA! Here is the website.
An example of one type of chart made from Hydrographic survey data
Charts and maps are clearly different. Now lets look at the science behind creating charts. The science is called Hydrography. (I found the next set of information on this site) Hydrography is “the science which deals with the measurement and description of the physical features of bodies of water and their land areas.” (CDR Gerd Glang – Chief, Hydrographic Surveys Division) To paraphrase: Special emphasis is placed on elements that affect safe navigation. Side scan sonars are often deployed to detect submerged dangers to navigation. Hydrographic data are collected and processed with specialized computer systems that store data in digital form and generate graphic displays. Charts must include enough hydrographic detail in order to adequately depict the bottom topography and portray the least (lowest) depths over critical features. (Like rocks that your boat will hit if you don’t know they are there!) This paragraph describes exactly what we are doing here in Alaska!
Navigational charts contain accurate and reliable information about features that assist ships in their travel. It can take up to two years to create a navigational chart! There are multiple sets of data that are used to ensure the charts are accurate. Just think about the data I have discussed so far. There are ELAC sonar readings of the deep water. The RAINIER takes ELAC readings in the deeper waters off the coastline, and the smaller boats take ELAC readings of the deeper waters closer to shore where navigational hazards to the RAINIER are present. This is also data the smaller boats using RESON sonar readings of shallower waters, the gathering of tide gauge readings, and the measurement of GPS benchmark levels.
While it is unusual for both the RAINIER and the smaller boats to be surveying at the same time, it helped complete this project in good time. Usually, the six smaller research boats complete the survey work while the RAINIER serves as a command, logistics, and data processing center. Layers upon layers of data from all the boats and ship go into making charts. Like I said before, it can take up to two years to complete a chart with all the new survey information. While charts are being developed, sometimes new information becomes available that is critical to navigators, like a new hazard. This information is communicated immediately and notices are sent out monthly so mariners can update their charts. NOAA has set a goal to move from survey to chart in 90 days – based on the amount of time it takes to gather data safely, this will be challenging! But if newer technologies can provider quicker turn around time it will speed up the process.
I watched the careful and deliberate review of data gathered by multibeam sonar, and as with any technology, there are limitations. Human oversight, review, and careful analysis of the data are important links between the gathering and use of the survey.
Survey Tech Krynytzky reviews ELAC data
A note of interest pertaining to navigational charts
Did you know that Thomas Jefferson created the US Coast Guard & Geodetic Survey Office in 1807? (1807 – 2007… NOAA is celebrating its 200th anniversary!). The US Coast Guard & Survey Office was the first scientific agency of the United States government. The Coast Survey Office and the USGS benchmarked, mapped, and charted the United States as it grew, and now there are multiple agencies providing data that describe a global model. This mathematical model is called Geodesy (Pronounced Ge-oh–des- see.) It has helped us understand the actual shape of the earth – it is not a perfectly round sphere, it is an oblate spheroid squashed down at the poles and bulging a bit at the equator! The Geodesy group is developing and refining a mathematical model that starts from the center of the earth and works its way out in to solar system. It takes into account the movement of the earth around the sun, and the sun within the spiral of the galaxy. As the entire unit of our solar system moves, subtle changes to the tides occur. It seems that this occurs on a nineteen-year cycle. Being able to track data over time at different locations – satellites, sonar readings, survey readings, etc. help us understand changes from the earth’s core, to the surface (tectonic plates, sea floor and land formations), and the oceans tides. It is quite amazing to think that a mathematical model can take all of that into account. Learn more here.
Think about how important it was to back in Thomas Jefferson’s day to understand navigation to and from the United States. For example, how to travel in order to trade and discover where to develop ports, and where not to! Think now about how important it is to understand how changes in earth impact human activity – trade, recreation, where to build homes away from storm zones, flooding, etc. What are safe numbers of fish to harvest so they can replenish? With the melting of the polar caps, imagine how important knowing how the mean high and low tides will change. The Tide Gauge survey that we completed in Dorothy Cove was last done in 1924! The work of NOAA, its’ agencies and that of the RAINIER are very important.
In the week since I have boarded this ship, the RAINIER and it’s crew have surveyed 462 Nautical miles, checked tide gauge data, reviewed data from the surveys to ensure their quality, and planned the next stage of their journey. In 2006, 1,464 Square Nautical Miles (SNM) were surveyed. There are 21,660 SNM that are considered critically important and have yet to be surveyed. See the 2007 Hydrographic Survey Priorities Report for more information.
Personal Log: Food equals Happiness
I have yet to talk about the food, and since my students love to eat I have to let them know how well fed I am on this ship! Imagine keeping sixty people of various taste-preferences happy. This is job of the cooks and stewards in charge of feeding and providing stores to the crew. I have never had such a variety of food before! There are always two or three choices or combinations of foods for every meal in hopes of making everyone happy. Fresh soups every night! There are fresh vegetables cooked just right – never over cooked! The salad bar and the ice cream freezer are always available (and a banana sundae with two or more ice cream types, chocolate sauce and chopped nuts is a great dessert. My favorite end of the day treat is “Foye Hot Coco” – a recipe he shared with me. If you meet him, be sure to ask him to teach you how to make it!) Over the week I have had the choice of barbeque ribs, prime rib, beef tips, roast veal, chicken, different varieties of rice, different styles of potatoes, and a host of tasty vegetarian dishes (yams masala, gado gado, pesto wraps). (Did I mention the gravies – they are delicious!) There are six different types of hot sauce and a host of condiments! Fresh fruit is always available (pineapple, mango, melons, grapes, cherries, you name it!) There are fresh made desserts every night and fresh-baked cookies during break times. All the water, coffee, juices, Nesquick, hot coco, tea, etc. that you could want.) I haven’t even started to talk about breakfast and lunch –there are treats galore- at least six kinds of cereal- and I will be lucky to leave this ship at the same weight as when I climbed aboard. There are even special occasions – like when Raul caught a 50-pound halibut the other day and donated it to our dinner one night. He made his own homemade batter and deep-fried pieces of halibut so we could have fish tacos! They were awesome! (Guacamole and mango salsa on top!) Floyd, Sergio, and Raul know how to keep us happy, healthy, and keep our bellies full!
The other really cool thing I have learned about here is satellite radio! I have got to get it installed in my boat, camper, truck, heck even the lawn tractor! The sound quality and choice of programming (without commercials) is incredible! Speaking of music, there are two really cool bands I have learned about on this trip – Great Big Sea, and Flogging Molly (which my students who love My Chemical Romance will really enjoy!)
Question of the Day
Topic 1: Are there internship opportunities for students who are interested in exploring careers in navigation, charting, mapping, computer sciences, Officer Corp, etc? How many NOAA agencies are there?
Topic 2: What geometric theorem can you use to determine the length of an unknown side? Hint: Hypotenuse.
Topic 3: What other expeditions and scientific endeavors did Thomas Jefferson initiate?
NOAA Teacher at Sea
Ginger Redlinger
Onboard NOAA Ship Rainier July 15 – August 1, 2007
Mission: Hydrographic Survey Geographical Area: Baranof Island, Alaska Date: July 22, 2007
One of five Geodetic Survey Benchmarks at Dorothy Cove
Weather Data from the Bridge
Visibility: 4 Nautical Miles
Wind directions: 190°
Wind Speed: 6 Knots
Sea Wave Height: 0 – 1
Seawater Temperature: 12.8° C
Sea-level Pressure: 1010.0 millibars (mb)
Cloud cover: Cloudy &
Rain Temperature: 13.9° C
Mariner Words of the Day: Port & Starboard
Port and starboard are directional words indicating the sides of the ship. As you are facing the bow (front) of the ship, port is on the left side, and starboard on the right side. How to remember? Port and left both have four letters.
Science and Technology Log
Position A
Today was the day that we wrapped things up in this area by re-surveying a few sections to improve the quality of the initial set of readings, took horizontal measurements of the water-level (by hand) in order to improve the accuracy of area mean tide (high and low) data, and prepared the ship to move south. I have written earlier about the attention to detail, safety, and teamwork in the day-to-day operations, the gathering and processing of data, and daily production of results. Today I am adding the noticeable value of the work done by NOAA vessels as noted by a gentleman and his family who came to watch our tide gauge survey crew work this morning. He said, “You people with NOAA do a great job, and the folks in Sitka use your information all the time. We are thankful that you have provided us with the information we need so we can enjoy navigating the waters around here.” That was a good way to start the day. I highly recommend that you read TAS Beth Carter’s description of mechanics and tools involved in Tide Gauge Surveys.
Position B
While it sounds easy, it is actually very challenging to collect accurate measurements to the specifications required for this work, which are to the millimeter. Everything has to be level and measured at precise locations using benchmark geodetic locaters installed. Using the same locations (the geodetic benchmarks) each time you take measurements ensures consistent use and interpretation of horizontal measurements. The horizontal measurements between the benchmarks tell us whether or not the land height has changed. This is important information to give context to any changes the tide gauge measures. If the mean tide level has changed, you need to know if the land level has changed too! Much of the data we gathered today is also connected to the GPS (Global Positioning System.) I have an old farmhouse and level is not a word I can use to describe most of it. Making a precise measure by establishing a level place on a slippery, rocky beach makes taking measurements in my house seem like a piece of cake! The survey scopes at the benchmarks are looking across about 50 feet of water to their left at the picture on the left (below) – which is the rod at another benchmark. The next picture is the rod at the third position, which would be on the beach about 90 degrees, and 50 feet to the left of the survey scope (and the same, but the right, of the rod on the other side. When the lines connect, we have a triangle!
Position C
If you would like to see how challenging this can be, here is a simulation that reverses the location of the surveying scope eyepiece (with the crosshairs) and the rod (with the height indicators), but it will definitely give you an appreciation for the challenge of accurate measurement over distance: Imagine yourself with a standard size metric ruler and a piece of paper with a crosshair pen line about 10 cm long each direction. About one centimeter from the top and the bottom of the vertical line draw another crossing horizontal line 2 cm long, about 1cm on each side. Tape the paper to the wall across the room and walk to the other side facing the paper you just taped to the wall. Now hold up your ruler an arm’s length away, vertically, with the 0 on the bottom so you are reading the measure up from the bottom of the lines. Close one eye. Try to identify exactly the millimeter at each horizontal line, for each of the horizontal lines. Could you line it up exactly? Was your ruler and paper both “level” so you could? Hard to see? Hard to measure? Now you see how challenging this can be! Imagine making an accurate measurement over a distance of 50 to 75 feet! It is also important to note that multiple measures must be taken that have to agree on the same result, with allowance for a tiny margin of error (again, a two millimeter margin of error is allowed – that is one millimeter error for the upper half of the cross hair and one for the lower half).
Here is another view of the survey scope lining up with the rod. If you look at the bottom of the rod you can see Geodetic Benchmark.
In the case of Dorothy Harbor, there are five Geodetic benchmark markers. When the line of sight is either obstructed, or too great to make an accurate reading, then a “turn point” is established. The turn point is set on a turtle (not a real turtle) which is a heavy disk that serves as set location upon which to balance the rod so measurements can be taken. Measurements must be taken from, and at, each location that needs the turn point to ensure that the data is correct. Since this data is used to ensure the accuracy of tidal data in this area, and to supply information to the GPS – it must be done correctly. In the natural environment, this is quite challenging. The measurements are recorded on a PDA and returned to the ship for processing. Right triangle geometry, simple algebra, or trigonometry can be used to determine the accuracy of the measurements at each point. If you have the markers at two line-of-site points (say to your right and your left) and are measuring the distance from where you are to each of the two points, you can figure out from your findings what the distance is between the two line-of-site points. By moving the rods to each of the five markers, you can verify that the measurements made from each location are accurate. Taking and using multiple measures is common sense to those who do it all the time like the NOAA crew. For many people, learning why is important. Some people learn it through building things — like the common sense rule to measure more than once before you decide to cut lumber, or to measure from two directions before you square a corner – you have to be sure you are right before you move to the next step!
Once we were done with our measurements we ate lunch, then began to disassemble the Tide Gauge measurement assembly. The divers came in later to remove the equipment anchored underwater, and everyone returned to the ship to prepare for the evening’s departure. The crew was exhausted as we had to climb, wade, carry, move, hold, disassemble, dive, and concentrate intently on our tasks. Tonight we head south at 2100 towards Ketchikan and begin surveying a different area tomorrow.
After helping the crew complete today’s work, I realized how difficult it is to gather precise measures by hand in dynamic, ever-changing conditions. (The wind picking up in the middle of a read — moving the 15’ high rods just enough to throw off the desired accuracy – so you have to start all over, the trees interfering with the line-of-site between the benchmarks and rods – people pushing back tree branches, trying to triangulate points on an unstable rocky beach, you get the idea…) Despite all these challenges, the crew gets the job done. This is what the navigating public (and commercial navigators), appreciate about NOAA’s work. As I heard, straight from the pilot and family of the Sitka-based pleasure craft anchored in Toy Harbor.
I also appreciated the seafloor mapping tools provided by the technology on the ship. What if we had to take seafloor readings by hand! (And hope that we had found all the submerged rocks!) I think technology for surveying has made mapping the seafloor easier, at least at the measurement stage : )
Question of the Day
Topic 1: How are navigational charts, topographical maps, and road maps alike? How are they different? (The answer to this question will be explored in the next journal).
Topic 2: Where can you find a geodetic benchmarks in your area? Outside of your area: What is special about the markers that are used in Disneyland (not created by the USGS)?
Topic 3: What are the tools and techniques of surveying?
Today’s Mariner word: Fiddly (Pronounced Fid-lee) the fiddly is the room above the engine compartment.
Survey Techs Hertzog & Boles prepare to measure sound velocity with CTD.
Wow – what a day. At 0800 hours we were briefed on our day’s work plan. I was joining an experienced pilot (Coxswain) and two survey technicians on a research boat to take sound velocity readings in an area off the coast of Baranof Island. First, we had the launch the boats from the ship. The experience boat crew and I watched as the ship’s deck hands lowered the boats from their racks by crane to the side of the ship at a level that allowed us to climb aboard. (A few feet above water level). The deck hands held the boat in position from above by crane, and on the sides to keep it from rocking back and forth and bouncing against the ship. Additional hands held ropes attached to the hooks and cables that we were going to release fore and aft hooks once the boat was in the water. Of course, the boat pilot needed to get the engine running right when the boat hit the water to keep it in the correct position against the side of the ship. Launching while underway is challenging, and must be done correctly in order to ensure everyone’s safety. The boat’s personnel released the hooks and the deck personnel winched the hooks back to the starting positions. Deck hands on ship held the boat in position with ropes fore and aft. Once everything on the boat was checked and running the aft line was called in, then the bowline, and we were underway. This was another example of the amazing teamwork I have witnessed everyday on this ship.
When we arrived at our survey area the technicians used a CTD to take an initial reading of the speed of sound at the surface of the water, then lowered it again to take the same reading at a much lower depth. (If you remember the last journal entry, this is the same process used to correct for the speed on sound on the RAINIER.) The readings are entered into the boat’s computer prior to taking any readings. While we took readings along our survey lines I asked the survey crew a question, “what about large mammals, won’t they interfere with the sonar readings? The answer was “yes, if a whale is below us it would appear as a shadow on the computer screen. Algal blooms and kelp beds can also affect the quality of the readings.”
Survey Tech Boles monitoring the data recorded by the ELAC transducer
We tracked back and forth across our survey area. The direction and length of each survey line was determined the day before, and provide to the boat’s survey technicians. No whales, algal blooms, or kelp beds today. Part of NOAA’s mission is to provide useful information to commercial navigators, and that includes fishermen. We were very careful to adjust our movement across survey lines to avoid interfering with the fishing vessels. During our time on the boat I asked the crew questions about their background, the Coxswain (person who pilots the boat and ensures our safety) has been at sea for over 30 years. He is amazing. He taught me how to pilot the board correctly. My first try was not very successful. The second time I was much better. I guess you could say that he is a good teacher, and a good seaman.
The two survey technicians on board track and record data. They have different backgrounds, but bring important skills to the task of gathering and reading data. The first, a young woman, has a degree in geology and works as a cartographer for the United States Geologic Service. She is working on this boat this summer. The other is a young man from Tennessee who received his certificate in Geographic Information Systems. I have to admit, without the man who piloted the boat and kept it on a narrow track of water fighting swells, currents, and avoiding fishing boats – the rest of us wouldn’t have been able to take readings. Everyone has something critically important to do.
Coxswain Foye keeping the boat on the correct lines to record data.
How did we get the data from the boat to the on-ship computers? The data is cabled in from the boat to the plotting room where all the cartography hardware and software is located. (One way is to plug in a cable and download!) The database contains recent and historical charts made of waters that NOAA surveys. The FOO (remember, Field Operations Officer) showed me a chart created in 1924 of the same area. The technology used back then was lead lines and sextants. They would start by moving to a location, and then drop a lead line until it hit the bottom, counting the fathoms from surface to seafloor. After recording it, they pulled up the lead line, and then traveled along as straight a path as possible, recorded latitude and longitude, and took another reading. I didn’t count all the readings taken in this fashion on the old map, but there were well over one hundred readings in the small section we were surveying, and the old map covered a region much greater – the entire coastline and out to sea in the area we are working. The FOO then did an amazing thing by overlaying the new map readings over the old map – it was amazing how accurate the old map still is!
You can find out more about early navigation and see maps made a long time ago here.
For information about prior work done in this area visit the NOAA photo library.
The need for accurate navigation information is as important now as it was back then. Personal and commercial craft need to know where it is safe and where it is dangerous. The FOO and I talked about how nice it would be someday to have a holographic representation of an area you are navigating (whether it is sea, lake, or river) that would allow you to see the bottom of the sea, the coastline, and the cloud layers. Maybe future mariners, oceanographers, and technicians can make that available for everyone.
Questions of the Day
Topic 1: There are additional corrections that the survey team includes in the analysis of the tracking data. Besides velocity of sound readings, what other data about the water in an area would be important to take into account? Hint: The moon has something to do with it.
Topic 2: Where can you earn a certificate in Geographic Information Systems (GIS), or a degree is Geology or Oceanography in the Northwest? Where else can you learn about GIS? Where can you learn the skills you need to work with the engineering crew, deck crew, or the Officer Corp in NOAA?
Topic 3: Can you name the earliest cartographer of this area, and when he did his work? Who else has surveyed this area?
NOAA Teacher at Sea
Ginger Redlinger
Onboard NOAA Ship Rainier July 15 – August 1, 2007
Mission: Hydrographic Survey Geographical Area: Baranof Island, Alaska Date: July 17, 2007
Weather Data from the Bridge
Temp: 56 degrees
Wave height: Negligible
Cloud: Cloudy and Fog
Visibility: ••• mile or less
Mariner word of the day: Strait A strait is a body of water – straight straits are straight bodies of water, but there are no wiggly straits. (Commanding Officer Noll provided today’s definition.)
Science and Technology Log
I got up early (0600 hours) to be sure to watch the crew navigate the ship from Peril Strait through Neva Strait, and then Olga Strait. Can you imagine navigating a 231 foot ship though a channel that is a slightly wider than the ship and its wake, with only 14 feet of water below the keel? Did you see the visibility distance in the conditions report? Imagine how difficult it would be to see another ship approaching! Well, these people are professionals. The deck hands steered the ship and watched from the decks with binoculars to catch any movement or objects on the surface of the water. The officers monitored two radar screens and checked the bearings constantly as they approached navigation markers. They checked their route on the gyroscope compass to be sure they were not drifting. They constantly communicated with each other in their own terminology so everyone knew exactly who was doing what and where the ship was at all times. Needless to say, the margin of error for passing through VERY narrow straits is small. The crew made a difficult navigation task looks easy. This crew, deck hands, engineering, electronics, stewards, survey crew, and officers are exemplary. I wish I could describe how well they work as a team – and I will try to help my students understand how important it is to work as a team –everyone has an important job to do.
The massive ship being loaded with supplies
When the fog cleared a bit I was able to see a variety of jellyfish in the water off the side of the ship. A junior officer told me that when we drop anchor I will see more jelly fish than I can imagine. I just hope my supply of camera batteries holds out! We will be entering deeper water in a few hours were I will be able to test my sea legs. (Which means that I will find out whether or not I will be seasick, or if will I be ok.) When we enter the sea beyond the bays, harbors, and straits that are protected from the seas constant motion, the boat will begin to move up and down and side to side with the waves and swells. After reading about the experiences of other Teachers at Sea, I decided to go the safe route and begin taking seasickness medicine ahead of time. Does that make me Pollo Del Mar? (Chicken of the Sea – just a little chiste (joke) there!)
If you want to follow our journey on a map start at Juneau, go south to Gastineau Channel then head through Stephen’s Passage, north to Peril Strait, then west through Neva and Olga Strait. Pass Stika then head towards Biorka Island. From this area we will head to our hydrography starting location and work as we travel.
A multibeam sonar transducer is installed on the bottom of the hull that will send signals to the ocean bottom and receives the data when it bounces back. How does it work? Commanding Officer Noll describes it best, “The multibeam sonar precisely measures the time and angle of transmission/reception of the sound signal. The ConductivityTemperature-Depth (CTD) casts help us determine the speed of sound, which more or less allows us to apply Snell’s Law layer-based corrections to the ray-tracing of the sound vector that results. The data is converted to a picture of the bottom of the ocean.” Here is a picture of the transducer on the hull of the ship. It is on the bottom of the ship’s hull, between the two posts that are holding the ship off the ground.
You may be asking, “why take speed of sound readings in the water before you survey?” Well, the speed of sound changes with the depth of the water so readings that pass through different layers have different velocities. Accounting for those changes by correcting the data creates more accurate charts and maps. For more information about Snell’s Law and the refraction of sound waves, visit here. The ship runs a 24-hour hydrography work schedule. The boat and crew will continue to collect and process data all day and night. This means that everyone will be working hard the entire time. If you would like to see a short animation clip of this work – click on this link.
Questions of the Day
How much faster does sound travel in the water than in the air? Why is the velocity of sound faster in deeper waters than at the surface? When you are mapping a deep part of the ocean, what impact would the changing velocity of sound have on the time it takes to travel from the transducer to the bottom, and back to the top again?
NOAA Teacher at Sea
Ginger Redlinger
Onboard NOAA Ship Rainier July 15 – August 1, 2007
Mission: Hydrographic Survey Geographical Area: Baranof Island, Alaska Date: July 16, 2007
Weather Data from the Bridge
Visibility: 10 nautical miles (nm)
Wind Speed: calm
Sea Wave Height: none
Cloud cover: Partly Cloudy
Science and Technology Log
Today’s mariner word: Athwart (pronounced a-thwart) Athwart is a directional word that means “across.” The ship’s “hallway” is the known as the athwartship passageway! Two other directional words are important to know too, “fore” indicates forward, and “aft” indicates the rear part of the ship. Today was a training day. It was fun learning all sorts of new words (or learning about new contexts for the some of the words I already know. There is something really fun about getting out our your world (most of mine spent on land) and voyaging into some one else’s. Moving just beyond your “comfort zone” makes you appreciate that no matter how much you know there is always something worth learning.
Ships are well-run organizations. There is a chain of command for communication purposes that ensures that even in the most difficult situations, someone knows what should be done, in what order, where it needs to happen, and when. This is a good arrangement in case of an emergency, but also to help the ship run smoothly as it prepares to travel or when it is underway.
An example of this happened today when I heard the announcement “All hands on deck for stores.” Which means, “okay everyone, the food and supplies for our next voyage are here and we need to bring them onboard.” They are brought from the dock to the ship’s deck, from the ship’s deck to elevator, and from the elevator to the correct storerooms a few levels below the main deck. We made a “fire line” and worked together passing the boxes from one person to another. Everyone helped-out and in a short period of time, an entire truckload of supplies to feed and maintain 60 people for a 16-day voyage were stored. (Many hands make light work. Many well-organized and hard-working hands make it VERY light work.)
I learned about the hand’s (people who work on the ship) schedules and assignments in order to learn when and where I can expect to see people, and what they will most likely be doing. I studied the ship’s diagrams and found the library on my own! I don’t think I will need to leave breadcrumbs anymore to find my way around. I leaned about Emergency Escape Breathing Devices; what they are, how they work, and how to use them. There are, in short, carbon dioxide scrubbers! I also learned about the RAINIER’s procedures, by reading a binder labeled “Standing Orders,” which provided good background on how everyone on board is expected to work, what to do in case of an emergency, and what emergency communication sounds like.
The CO (Commanding Officer) spent time explaining how to get additional information for my logs. The FOO (yes, sounds as it is spelled) Field Operations Officer was very helpful in providing me information about how work is planned, how to get additional graphics resources for my lessons, and what to learn about so I would have a great cruise. He also asked me what I wanted to get from my experience. XO (Executive Officer) made sure I had provided them with the information they needed for emergency contacts. The Junior officers are also very professional, helpful and informative. Chief Electronic – passwords and email account, and then there are two hands that helped train me on how and when to use my safety equipment and wear my survival suit.
We were underway by 1800 hours (6pm), and watching the crew get the ship underway was organized and efficient. Try to imagine what it would be like to coordinate, simultaneously, 60 crew members that each have a task, switching power supplies, testing systems, starting engines, testing the bow thruster, lowing a skiff for off-boat rope management, managing the ropes from the dock to the boat, raising the skiff back onto the ship while underway using a crane, while lowering the ropes and stowing them properly below deck. Meanwhile the officers are navigating busy ship channels (4 cruise ships in the bay, a gill net fishing boat, and ferries.). Did I mention that dinner needed to be served to the entire crew during 1700 hours? This team of people is amazing.
I could picture many of my students having a great time as a crewmember on this research vessel. I hope that I can bring back enough information to help my students see themselves as researchers, mariners, merchant marines, or join the NOAA Officers corp.
Question of the Day
What is the distance in nautical miles (nm) between Juneau and the entrance to Peril Strait? If we travel at 10 knots, how long will it take us to get there?
