Cassie Kautzer: High Tide, Low Tide , August 30, 2014

NOAA Teacher at Sea
Cassie Kautzer
Aboard NOAA Ship Rainier
August 16 – September 5, 2014

Mission: Hydrographic Survey
Geographical Area of Survey: Terror Bay
Date: August 30, 2014

Temperature & Weather:  10 ° C (50° F), Cloudy, Windy (NNW winds, 5-10 kt)

Science & Technology Log

NOAA ship Rainier anchored in Japanese Bay.
NOAA ship Rainier anchored in Japanese Bay.

Since my last blog, we have come and gone from Japanese Bay, and moved on to Terror Bay.  As we were coming into Terror Bay through a narrow passage, we all got a dangerous reminder about how important hydrographic survey work is.

The nautical charts used to map our route into Terror Bay showed a depth of 25 Fathoms (150 feet), at a specific point we were traveling over.  The actual depth at that point, however, was only 7 Fathoms (42 feet).  That is only one third of the depth that was charted.  The Rainier’s draft is slightly over 14 feet (the depth from the waterline to the bottom of the Rainier’s hull, or bottom), so we were safe traveling over the 7 Fathom location.  Seeing this big of a DTON (Danger to Navigation) from the nautical charts to the actual depth, however, could be a cause for alarm.  How many other measurements are wrong?  Can we safely get the ship back out of Terror Bay?  With these thoughts in mind, one Launch boat was sent out today to survey and recon (explore/inspect) Terror Bay and ensure that we have a safe path out!

While a Launch Boat surveys, many other crew members have been busy installing and leveling new tide gauges in Terror Bay.  Tides are the daily rise and fall of the oceans, caused by the Sun and Moon’s gravitational pulls on Earth’s oceans.  The difference between low tide and high tide is the tidal range.  (The world’s biggest tidal range can be observed in Bay of Fundy, Canada.  At Bay of Fundy, high tide can be as much as 53 feet higher than low tide- all in a matter of six hours.  (onegeology.org)

high tide low tide

tidal range

Gauging sea level is trickier than just sticking a ruler or tape measure in the water because ocean waters don’t have one steady level.  Tides and currents constantly flow up and down, causing tides and water levels to be very important for hydrographic survey and other work at sea.  Hydrographic surveys are conducted at all different levels of tides.  This means shoal areas, rocks, shipwrecks, and other hazards are surveyed and recorded at all different levels of tides.  After hydrographers survey an area, they bring all the recorded data back to the ship for processing.  In processing, the depth around any hazards or dangers to navigation must be corrected based on the changing water levels.  In order to determine the necessary changes due to tides, tide stations are set up near survey areas.

A tide gauge and horcon station (horizontal control) is being set up in Terror Bay.  (Photo by Barry Jackson)
A tide gauge and horcon station (horizontal control) is being set up in Terror Bay. (Photo by Barry Jackson)

To set up a tide station, a team needs to go ashore near the area to be surveyed and explore- looking for good, stable, permanent places (like bedrock) to install tide gauges and a tide staff.  After an area is identified, a team is sent to install benchmarks.  Benchmarks for tides are like those that can be found at national landmarks and mountain peaks. Tidal benchmarks are multipurpose: they provide a frame of reference to ensure the tide staff and tide gauge orifice are stable (not moving relative to the land), they allow for comparison data in later years if we return to survey or work in this area again, and they provide stability data (the Earth’s surface, including under the oceans, is constantly changing).

Senior Survey Tech Barry Jackson drill into bedrock, preparing to install a benchmark.
Senior Survey Tech Barry Jackson drill into bedrock, preparing to install a benchmark.
Here is a benchmark cemented into bedrock near the shore line.
Here is a benchmark cemented into bedrock near the shore line.

Along with installing benchmarks, a tide staff must be set up.  A tide staff is large meter stick used for both leveling of benchmarks and for taking readings on water depth over an extended period of time.  After all instruments for the tide station are set up, the tide staff must be observed for several hours.  While observing, the water level must be measured with the tide staff and recorded every six minutes.  This data will then be compared with the data gathered by the tide gauge instruments, and hopefully, will match.

Cheif Survey Tech Jim Jacobson and Assistant Survey Tech Thomas Burrow install the Terror Bay tide staff during low tide.
Cheif Survey Tech Jim Jacobson and Assistant Survey Tech Thomas Burrow install the Terror Bay tide staff during low tide.
ENS Micki Ream reads measurements from the tide staff during higher tide.
ENS Micki Ream reads measurements from the tide staff during higher tide.

While benchmarks and a tide staff are being installed, often another team is working to install the tide gauge.   Tide gauge stations are instruments used to measure the change in sea level, over time.  They are powered by solar panels and include tubing and a sensor that must be secured under the water by a dive team.  The sensor, or orifice, must be placed on the seafloor, and anchored there, where it will always be underwater, even in low or negative tide.  The sensor uses air pressure, from a pump on shore, to measure the water depth.

Dive Master ENS Katrina Poremba and Diver ENS Micki Ream work to weight down the orifice tubing and anchor the sensor to the seafloor.
Dive Master ENS Katrina Poremba and Diver ENS Micki Ream work to weight down the orifice tubing and anchor the sensor to the seafloor.

Once everything is set up, a team will do a leveling run to measure the height of the benchmarks relative to the tide staff.  Meter sticks are held level at each of the benchmarks.  One person then reads a top, middle, and bottom thread measurement from each benchmark through a special vertical level on a tripod (kind of like a telescope).   Benchmarks are measured and compared from A to B, B to C, C to D, D to E, and the primary benchmark to the tide staff.  Then, these are all read again in a backwards run to double check and hopefully close the deal.

Assistant Survey Tech Eli Smith sets up for a level run while ENS Micki Ream prepares for data collection.
Assistant Survey Tech Eli Smith sets up for a level run while ENS Micki Ream prepares for data collection.
This is the level, put on the tripod, that allows Hydrographers to take vertical thread measurements from each benchmark.
This is the level, put on the tripod, that allows Hydrographers to take vertical thread measurements from each benchmark.

Survey work nearby can now begin, because hydrographers will have the appropriate tides data to make necessary corrections to the depth measurement gathered by the survey launches in the area!

Personal Log

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For My Students

Find out more about TIDES *here*

Dana Clark: Alaska Goodbye, July 2, 2014

NOAA Teacher at Sea

Dana Clark

Onboard NOAA Ship Fairweather

June 23 – July 3, 2014

Mission: Hydrographic Survey
Geographical area of cruise: South Coast of Kodiak Island
Date: July 2, 2014

Weather Data: Latitude – 56° 56.7′ N, Longitude – 153° 41.5′ W, Sky Condition – 1/8 clouds, Present Weather– clear, Visibility– 10+ nautical miles, Wind– 5 knots, Temperature– 16.1° C Science and Technology Log

Dana Clark
Dana Clark and ENS Joe Brinkley aboard a skiff returning to the Fairweather after tide observations

Today is my last full day on the Fairweather and tomorrow I will be departing when we dock in Seward, Alaska. I could not have asked for a better final day! But first, yesterday I went out on a launch to survey a near shore polygon. Let me explain. A project is the survey area that the Fairweather is tasked with, in this case, Sitkinak Strait. The project is then broken down into sheets which are areas to cover each day. The sheets are divided into areas called polygons and each day, the launches will be tasked with surveying specific polygons. Yesterday, our polygon was very close to shore. This was difficult because the rocks and vegetation could be hazards. The surveyor in charge, Pat, had to be in constant communication with our launch driver Rick so that they could maneuver safely as we used the multi-beam sonar to scan the area. Since we were so close to shore I kept a steady scan of the landscape for bears. I did this not because we were too close and in danger from a bear, but just because I wanted to see one. We accomplished our task and finished our polygons and did not see a bear, but we did see a brown fox walking along the black sand beach!

Bald Eagle
Bald Eagle, Japanese Bay, Kodiak Island, Alaska

Now, for today. I did tide observations in Japanese Bay and as we were setting up I snapped this picture of a bald eagle in flight with prey in its claws, possibly some kind of rodent since it appears to have a tail! (Click on the picture to see it better) We took tide observations which were interesting today for three reasons. First, the tide level was totally different than it was last week when I took measurements. If you look at the two pictures below, one from June 28th and the other from today, July 2nd, you can see how much lower the tide is. Look at how close to the staff I was today and how far away last week. The water actually went lower than the tide staff today! Earth Science is so interesting.

Dana Clark Tide Observations
Dana Clark reading water level off tide staff, Japanese Bay, Alaska, June 28, 2014
Dana Clark reading water level off the tide staff
Dana Clark reading water level off tide staff, Japanese Bay, Alaska. July 2, 2014

Now, the second and third reason I found tide observations so cool today did not have anything to do with the tides. It was all about the animals. And no, it did not involve a bear. Second reason it was interesting was the bald eagle in the picture above. I just love how I was able to capture it with its wings spread so majestically. It has a nest in the tree that it was flying into. Since it was carrying lunch in its claws, I thought maybe it was taking food to the nest to feed baby eagles. What do you think? Now, third reason tide observations in Japanese Bay were so cool today was because of swimming deer! I know I should have led with that but I knew it would be pretty awesome to put a swimming deer video into the middle of my blog. The video is a little jumpy because I was fighting the waves in  a small boat called a skiff. Check out the video!  Before I thought to start videotaping I was able to capture a picture of them swimming!

Swimming Deer
Swimming Deer. Japanese Bay, Kodiak Island, Alaska.

Scientist of the Day Today I would like you to meet Shauna Glasser, a First Assistant Engineer for NOAA who is currently aboard the Fairweather. It’s old hat for Shauna to travel wherever the Fairweather may take her. Growing up, she moved so many times that college was the first school she went to for four years in a row! Even though she moved often she still managed to be successful in her academics. She received a BA in Marine Engineering Technology from California Maritime Academy but it was by chance that she even enrolled there. As a senior in high school she received a postcard in the mail from this college.

Shauna Glasser
Shauna Glasser, First Assistant Engineer on the Fairweather

Knowing nothing about the school, Shauna decided to visit the school for a week long introduction program to see their campus and curriculum. She knew she wanted to be a marine biologist and she enrolled. However, before college began, her math teacher from high school recommended she take a summer class in chemical engineering. Shauna always excelled in math and she really liked the engineering, but not so much the chemical side. She soon switched paths from marine biology and became a marine engineering major.

Shauna has been with NOAA for five years and has worked her way up in the job. As first assistant engineer she is the person on the ship directly under the chief engineer. There are eight people who report under first assistant engineer. The engineers do all the maintenance on the ship and they keep it running. Shauna says that this is a job that is in high demand. The Fairweather, along with two other ships in the fleet, will actually be docked at port starting July 7th because they are in need of more engineers aboard. The ships can’t run without them! This young engineer has risen to a leadership role in her field and sees being a chief in her future. Shauna says, “Go for it! Ask questions, be yourself, think smart, and you can do it!”

Personal Log

NOAA Ship Fairweather
NOAA Ship Fairweather, July 1, 2014

My day today is ending just as magical as it began with several more animal sightings. We are underway to Seward, Alaska where I will say goodbye to the wonderful crew of the Fairweather. As we got underway we had a fire drill and then a little while later, an abandon ship drill. As the crew at my drill station were standing on the port side of the ship wearing our life jackets, hats, and in possession of our survival suits, a pod of orcas swam by spouting from their blowholes. They play and blow as they pass by our ship. Then, after dinner I am working on this blog and take a break and go to the bridge to see what’s going on. There were pods of orcas to the port side and humpback whales a mile north of us. The humpbacks were spouting and breaching. I have an out of focus picture of a whale going straight up in the air. It looks like it’s pirouetting. The crew on the bridge said that this was a large sighting of whales and everyone was excited.

Dana Clark on the Fairweather
Dana Clark at the helm of the Fairweather with Jim Klapchuk

I begin looking at the equipment on the bridge and asking questions when I was asked if I would like to steer the ship. Nervously I said yes. They explained that it was currently on a type of ship auto pilot which they would turn off and I would take the helm, similar to a steering wheel on a car, and I would be in control of the ship’s path. Jim Klapchuk, an Able Seaman on the Fairweather, showed me what to do. I would be at the helm and would continue in the correct direction by looking at my gyroscopic compass and my rudder angle indicator. The gyroscopic compass would tell me my heading, which was 030° which would keep me going north-east. The rudder angle indicator would move every time I moved the wheel because turning the wheel turned the rudder and the rudder changes the course of the ship. Keeping this lesson in mind, they turned off the auto pilot and I was steering the 231 foot ship on a heading for Seward! I kept constantly looking at the numbers and trying to keep it at exactly 030°. After a short while, the boat felt like it was swaying a bit so I gave the helm back to Jim and they set it back to auto. What a way to end my science adventure!

Fairweather navigational chart
Fairweather navigational chart that shows route from Kodiak Island heading to Seward, Alaska

A warm thank you to all the crew aboard the Fairweather. I have learned so much and will take back to my classroom a new excitement along with tons of science. Terms like hydrographic, surveys, hydrographer, polygon, launch, CTD, gyroscopic compass, swells, tides, charts, cartographer and many more will be introduced. I have also enjoyed getting to know you and hearing about your lives. You are a talented group. And I learned to play cribbage – thanks Tim and Charlie!

Question: But first, an answer to the last plant or animal poll. It appears that all of you know what a jellyfish looks like because you voted animal. Thanks for voting and thanks for following my blog. There are a lot of jellyfish here in the Gulf of Alaska and I will leave you with a few of my favorite shots. It’s amazing how each one looks so different. Which is your favorite? Vote in the poll below!

Bright purple jelly fish
Bright purple jellyfish
White jelly fish
White jellyfish
Japanese Bay, Alaska
Yellow and white jellyfish
Pink jellyfish
Pink jellyfish
Orange jellyfish
Orange jellyfish

Dana Clark: Alaskan Launches, Tides and Bears, Oh My! June 28, 2014

 NOAA Teacher at Sea

Dana Clark

Onboard NOAA Ship Fairweather

June 23 – July 3, 2014

Mission: Hydrographic Survey

Geographical area of cruise: South Coast of Kodiak Island

Date: June 28, 2014

Weather Data: Latitude – 51° 12.83′ N, Longitude – 152° 29.54′ W, Sky Condition – 1/8 clouds, Present Weather – clear, Visibility – 10 nautical miles, Wind – 8 knots, Temperature – 21° C

Science and Technology Log

Dana Clark with Primary Antenna
Dana Clark with Ens. Joe Brinkley repairing horizontal control station, Cape Kaguyak, Alaska

Each day when I participate in hydrographic surveys I always tell the boat that today we need to see a bear. Recently, one launch survey crew saw a bear swimming in the water and it stopped and looked at them before swimming off to the land. This was my ideal situation. So yesterday I participated in a hydrographic survey and the driver got real excited for me when in the middle of a transit, he yelled that he thinks he sees two bears on the shore. As we use binoculars to see them we confirm that we have now seen…two horses! This sighting was by all accounts very interesting to the crew since no one knew that there would be wild horses on an island in Alaska. However, the day’s sightings of wild cows and horses did nothing for this Texan.

Bear chewed solar panels
Bear chewed solar panels, Cape Kaguyak, Alaska

Today, I did something different. I went with a survey group out in an orange work boat called an Ambar. This boat is different than the launches because it is a jet boat, which means it has an impeller versus an exposed propeller. This way, it can bring us right up to shore.

We had a two-fold purpose, first to repair a horizontal control station, HorCon for short, and then to make tide observations. The HorCon station logs GPS (Global Positioning System) data. The station has a GPS atenna and recording unit, radio modem antenna for remote communications, car batteries to power everything, and solar panels to charge the batteries.The antennas are on a fixed tripod. For this piece of equipment, the higher the better! It allows us to achieve better horizontal and vertical positioning for our multi-beam data. It tracks the satellites overhead, the same as our survey launches do, but since it is in a known position we can use these data to remove any atmospheric interference.

We hike a large cliff and at the top is the HorCon station. As we crest the hill, it is Joe in the lead, then Joy, then me. Joe says stop, there’s a bear on the ridge, and it’s only about 200 feet away! We quickly gather together to look bigger to the bear and it decides to amble away over the ridge. Then, two baby cubs that we hadn’t seen go following behind her! My day is made perfect. When we get to the horizontal control station we find out it wasn’t working because the bear had chewed the solar panels and pulled a cord out of the primary antenna. Check out the huge bite mark in the picture above! Joe repaired the cord, made sure the other solar panels were still connected, and we had the station up and communicating.

Dana Clark Tide Observations
Dana Clark reading water level off the tide staff, Japanese Bay, Alaska

First mission accomplished then off to do tide observations. Mostly, this consist of sitting on the beach and recording the current water level every six minutes. It was a beautiful sunny day and Japanese Bay, Alaska was the ideal place to be. On shore there is a gauge, tripod and antenna with a wire that attaches to an orifice underwater. There also is a staff in the water with measurements on it. A constant flow rate of air is maintained in the orifice underwater so we can measure the pressure of the water column. More pressure = higher tide. Just think, at higher tide there is more water pushing down on it, hence more pressure. The gauge correlates pressure values with how much tide we are actually seeing. So we take staff observations over two hours and every six minutes we take a minute of readings of how high the water is on the staff. We then download the data from the gauges and compare it to our visual data. It’s important to go out every week to get readings and make sure no bear or storm has bothered it.

Why do tide observations every week? The scientists here often see tide ranges in Alaska from -5 feet to +25 feet. They need to know the correct tidal effects so when they take depth readings with the multi-beam sonar they can adjust those depths to remove tide and chart the soundings at MLLW (Mean Lower Low Water), which is the chart datum. This is because the water level is changing every day with tides and they need to be accurate. This is real important in shallow areas.

Scientist of the Day

Tami Beduhn
Tami Beduhn in Barrow, Alaska, 2012. Photo courtesy of NOAA Fairweather

Today I would like you to meet Tami Beduhn, a Chief Survey Technician for NOAA who is currently aboard the Fairweather. She is the head of the whole hydrographic  survey department here on the Fairweather! She is not in NOAA Corps but is a wage mariner, which means she is getting sea time assigned to the Fairweather in order to get her Able Seaman credentials and she is not part of the uniformed services.

She’s here because she wants to be on this ship doing the work she does and her CO, CDR Zezula, sure is glad she’s here. He says, “Tami is technically outstanding, incredibly dedicated, and has a strong work ethic. She is the bedrock of the science, especially with a lot of new people this year, and I rely on her leadership to guide and mentor as well as maintain the high quality Fairweather is known for.”

As the chief survey technician, she manages the survey department and is responsible for quality assurance and control of hydrographic data aboard the ship. The highlight of her job is training the new recruits. Tami believes the key to a good hydrographer is having a good attitude, good computer and math skills, and a willingness to learn. And they must enjoy teamwork since living on a ship is like having a family that works together. Tami graduated from North Carolina State University with a BS in Marine Science and a Concentration in Geology and came straight to NOAA. Here’s a woman who’s at the forefront of her field, all at the age of 27 years old!

Personal Log

What a great day I had today! I saw a bear with her two cubs, two orcas, and three bald eagles! Here is a poor quality shot of the bear with her cubs below her and a little to the left. Below that is a bald eagle. The third picture  is me on top of the hill after fixing the HorCon station. You can click on any picture in my blogs to see it full size. And after checking out the pictures, make sure to vote in the poll below. The weather is perfect and I even got a little sunburned today. Life is good being a hydrographer in Alaska in the summertime!

Brown bear and her cubs
Brown bear and her cubs, Cape Kaguyak, Alaska

 

Cape Kaguyak
Bald Eagle, Cape Kaguyak, Alaska
Dana Clark Cape Kaguyak, Alaska
Dana Clark on top of Cape Kaguyak, Alaska

 

Question: What is this? Plant or animal? Answer in the poll below.

Japanese Bay, Alaska

Katie Sard: My Tidal Adventure and a Look into the Power Behind This Mighty Ship, August 13, 2013

NOAA Teacher at Sea
Katie Sard
Aboard NOAA Ship Rainier
July 29, 2013-August 15, 2013

Mission:  Hydrographic Survey
Geographical Area of the Cruise:  Shumagin Islands, AK
Date:  August 9-13, 2013

Weather Data from the Bridge:
GPS location:  54°49.910’N, 159°46.159’W
Sky condition:  OVC
Visibility:  5 nm
Wind: 10 kt, 135 true
Water temperature:  7.2°C
Air temperature:  11.0°C

Science and Technology Log

At the beginning of my time aboard the Rainier I couldn’t believe it when one of the hydrographers told me that it takes almost two years for the data that we are collecting right now to go into print.  After spending time with the scientists trying to understand the process, I have a better idea of why the data can take up to 24 months to appear on a chart.  There are numerous things to take into account: variables that need to be controlled for, inclement weather that may restrict completing data collection, limited personnel to process the data, reports that need to be written to accompany the data, and so on.  The point being is that it is not as simple as surveying the ocean floor and making a chart.

The FOO, Meghan McGovern, leads a morning safety meeting prior to sending out the launches.
The FOO (Field Operations Officer), Meghan McGovern, leads a morning safety meeting prior to sending out the launches.

The tides are one important variable that hydrographers must control for when they are collecting data. Tides constantly cause the depths of the water to change, but it is important for the charts to show the shoalest (most shallow) depth possible for safe navigation.

Notice how one low tide is lower than the other low tide.
Notice how one low tide is lower than the other low tide.

It’s not practical to only conduct surveys during low tides, so the data must be corrected to take water depth to a universal constant.  For most of the charts, NOAA uses Mean Lower Low Water as the control.  To explain Mean Lower Low Water, I have to review a bit about the tides themselves.  Most places, including Alaska, experience semidiurnal tides meaning that in one day, there are two high tides and two low tides.  If you look at the two low tides in one day, one of the two will be lower than the other one.   An average should be taken of the “lower low” water levels for 19 years.   This is how long the earth, sun, and moon to go through their various orbital eccentricities.  Typically, it is not reasonable to have a gauge installed for 19 years so by acquiring one 30 day cycle of tide data we are able to get approximately 90% of the solution and the remaining 10% is solved for using “primary stations” (ones which have a 19 year record) that are nearby.  This calculated average of the lower low tides is called the Mean Lower Low Water and all data is corrected to this value.

Before the water depth can be corrected to Mean Lower Low Water, the tides must first be measured.  The National Water Level Observation Network has stations all over the United States which give data on how to figure out local tide conditions.  The closest one to use in the Shumagins is at Sand Point on Popof Island.  In order to verify that the tides are being accurately predicted, the crew on the Rainier installs their own tidal gauge to verify the tidal data.

The tide station that the Rainier crew installed on Bird Island.
The tide station that the Rainier crew installed on Bird Island.

A tide gauge is installed on the sea floor near the coast line by divers.  It must be fairly deep so that it is always covered by water.  In order to verify that the tide gauge is working, a tide staff is installed nearby for the crew to take visual water level measurements every week for 3 hours in 6 minute increments. They use this manually collected data and compare it to the tide gauge to make sure that the gauge is functioning accurately and also to ensure that the gauge has not moved relative to the land after it has been installed.

One of the five benchmarks that was cemented into the bedrock at the tide station on Bird Island.
One of the five benchmarks that was cemented into the bedrock at the tide station on Bird Island.

It is a complicated process to install one of these tidal gauges, and they have to be calibrated to that Mean Lower Low Water.  In order to assure that we have a reference point on land, benchmarks are put in near the tide gauge. These benchmarks should be able to be utilized for centuries by anyone who wished to come back to set-up a tide gauge.

Last Friday I was assigned to the skiff (small boat) as part of the crew of people who would go observe the tide staff and complete other necessary tasks at the tide gauge station on Bird Island.  It was a 30 minute ride in the skiff from the ship, and when we got the island, the coxswain pulled the boat next to the rocks so we could quickly transfer ourselves and our gear onto the island.  A total of five benchmarks had been put into the bedrock during the last visit to Bird Island, and it was our job to verify the location of each benchmark.

I had the important job of pointing at the benchmarks to note their locations for the pictures.  The benchmark is embedded in the bedrock near my left hand.
I had the task of pointing at the benchmarks to note their locations for the pictures. The benchmark is embedded in the bedrock near my left hand.

We took GPS locations, measured from benchmark to benchmark, and took pictures with detailed notes telling where each of the five was located.  If something happened to the primary benchmark, there would be four back-ups that could be used to reference the location of the tide gauge.  It was also the responsibility of our crew to do the 3 hour tide staff observations, but bad weather only allowed us to complete one hour of data collection before we were required to return to the ship.

LT Mike Gonsalves takes a GPS location while sitting on one of the five benchmarks.
LT Mike Gonsalves takes a GPS location while sitting on one of the five benchmarks.
Measuring from one benchmark to the next.
Measuring from one benchmark to the next.
LT Mike Gonsalves begins taking tide staff observations.
LT Mike Gonsalves begins taking tide staff observations.

It constantly impresses me how many variables these scientists need to control for in order to get accurate depths to place on the charts.  I have only received a snapshot of the work that goes into one of these projects during my time aboard the Rainier.  I have begun to see a problem when so many people of this generation expect instant results and instant gratification. From now on it will be important for me to show my students that the scientific process is slow and arduous, but the overall results are impressive when you learn to appreciate and understand the steps that it takes to get there.

Personal Log

Earlier this week I had the opportunity to visit the engine room as the ship was getting underway.  Evan McDermott , a 1st Assistant Engineer on board, was kind enough to let me to follow him through the heart of the ship.  As we walked and ducked under the various equipment, I began to realize just how naïve I am about how the ship is powered.  As I began to observe and ask questions, I realized just how much time and effort it takes to get the ship in motion.IMG_4312

When I first went down to the engine room they had just turned the pumps on.  These pumps are used to help turn the rudders.  Each time the pumps are powered on, it is required that the engineers do a steering test.  I went with Joshua Parker, a GVA (General Vessel Assistant) in the engineering department on board, as he showed me how to complete the steering test with the rudder.

GVA Josh Parker helps to show me around the engine room.
GVA Josh Parker helps to show me around the engine room.

While we were anchored, the engines were powered down and we were running the basic functions of the ship with two generators which stay on 24 hours a day while the ship is underway.  When I came back to the engine room it was time to turn the engines on, and Evan walked me through how to do this.  Really all I did was push two buttons that he showed me, but it was neat to hear the engines come to life.

The two 12-cylinder engines that we have on board.
The two 12-cylinder engines that we have on board.

While I was in the engine room, I remembered several of the questions my students had when the CO came to speak to my class last year.  I seemed to remember a lot of students asking questions about the fuel that the Rainier uses.  I decided to do some investigating by asking some of my own questions.  It turns out that the ship is able to carry a total of 103,000 gallons of fuel at a time.  On a typical 18 day leg, the ship will burn about 30,000 gallons of fuel.  Evan pulled up a detailed Microsoft Excel sheet and showed me how they keep track of the fuel being used.  He showed me that while underway the ship typically burns about 2,000 gallons each day, but if the ship is anchored it is more like 600 gallons.

Something else I learned while in the engine room was how this ship uses fuel as ballast.  Normally on a ship, ballast is water that is taken in to help keep the ship balanced.  The Rainier has 17 fuel tanks all around the ship, and one of the reasons for this is to give the ship stability.

A diagram of the 17 fuel tanks on the Rainier.  Notice how they are low as they help with the stability of the ship.
A diagram of the 17 fuel tanks on the Rainier. Notice how they are low as they help with the stability of the ship.

For this reason, it is important that the fuel is burned in a certain order based on which tank it is in.  Once the engineers decide that they need to use fuel from a certain tank, it is transferred into two settlers.  This is where the water is allowed to settle out of the fuel before it is purified and transferred to the day tanks.  These two-day tanks are where the two engines suck fuel from directly.

The last thing that grabbed my attention in the engine room was the process on how the sewage is filtered.  I know it sounds gross, but it is such a simple chemical reaction that I feel compelled to share it!  The machine that is responsible for this treatment uses salt water and DC current.  The current is run through the water and breaks the salt (NaCl) into the ions Na+  and Cl.  The Cl ions go on to reform with the OH ions from the water forming sodium hypochlorite.  This substance acts to kill the bacteria in the sewage.  Chemistry at work!

Just another Day at the Office

Evan McDermott, 1st Assistant Engineer

Evan McDermott
Evan McDermott

After touring the engine room, I sat down with Evan to talk about his job and how he came to work for NOAA as a 1st Assistant Engineer.  He told me that he graduated from Massachusetts Maritime Academy with a BS in Marine Engineering as well receiving his US Coast Guard license.  I didn’t know what a Maritime Academy was until I came aboard the Rainier, so I asked him how he originally heard about this field.  Evan told me that in high school he went through a unique program where he spent two days each week doing marine engineering outside of his school.  A guidance counselor told him more about the benefits of  marine engineering, and that’s when Evan decided to apply to Massachusetts Maritime Academy.

During our conversation, Evan told me that what he enjoys most about his job is the variety of hands-on work that he gets to be involved in, and he also enjoys the scenery here in Alaska.  He is required to stand watches in the engine room for two 4-hour shifts while the ship is underway, and he also plays a supervisory role.  The engineering department on the ship is mostly responsible for the maintenance and operations.  I asked him to share the advice he would give to students hoping to get into this field of work, and he said that it is important to keep up on your math to become a marine engineer!  Evan told me that the Maritime Academy was a tough four years of his life, but that his hard work has paid off as he has now secured this job with NOAA.

Evan appreciates the fishing that is available in Alaska, and when not on the ship he enjoys snowboarding.

Your Questions Answered!

A friend from my high school, Derek Cusimano, works with similar technology that is being utilized on the Rainier.  I was excited to see the questions he had for me, and also to realize that I actually understood how to answer some of the more technical questions.  First he asked about the program that is used to collect and process the data on board.  It is my understanding that on the ship, Hypack is the navigation software that is used.  The bridge sees this screen, and the hydrographers use it to draw the lines to show where the ship needs to be navigated in order to collect the data.  Seafloor Information Systems (SIS) is the sonar software for the EM710.  Finally, CARIS is the software that is used to process the data once it is collected.

Derek also asked me about what positioning the crews use for their surveys.  The tidal gauges that I discussed in this post are used for vertical control, as the water moves up and down with the tides.  The scientists also have to take into account horizontal control.  They need to accurately be able to tell where their position is, because without that information the water depths that we are gathering with the sonar are useless.

ENS Bill Carrier and HST Brandy Geiger work to set-up part of the horizontal control station on Bird Island.
ENS Bill Carrier and HST Brandy Geiger work to set-up part of the horizontal control station on Bird Island.

Differential Global Positioning System (DGPS) is used from the Coast Guard station in Kodiak Alaska to gain accurate latitude and longitude.  However, the Rainier crew also installs their own GPS  base stations to correct the GPS positions acquired on the ship and launches during “post processing”.  For this project, a GPS base station was installed on Bird Island near the tide gauge and data is down loaded via a VHF radio.  These stations listen to all GPS signals and correct the locations for each satellite down to the decimeter.  This allows the Rainier to correct their GPS positions to have an accuracy of just a few centimeters.

The next question comes from my 2-year old nephew Ollie Burgeson.  He wanted to know what I was eating on the ship.  My answer to him is a little bit of everything!  I can’t say that I’ve had the same meal twice while out at sea.  Meals are at 0700, 1130, and 1700, and each day a menu is posted that tells what will be available for breakfast, lunch, and dinner.  The stewards also provide a stocked ice cream freezer and other snacks 24 hours a day.  Many know that I eat mostly vegetarian food, and each meal there is always a vegetarian option which several crew members and I enjoy.  While out on the launches, the coolers are packed full of food for the crew of each boat.  Sandwiches, fresh fruit, chips, and dessert are all included on the launches.

Did You Know…

humpbackwhale_noaa_large
Photo courtesy of NOAA.

On Sunday I saw at least a dozen whales while I was looking out over the waters of the Shumagins.  The ship was anchored while the launches were out gathering data.  It was such a clear day that I decided to spend time on the bridge whale watching.  It didn’t take long before I saw several breach in the distance.  I was told by some of the crew that I was observing humpback whales, Megaptera novaeangliae.  I didn’t know much about them, so I decided to do a bit of research.  Here are some of the interesting things I learned about humpback whales:

  • Humpback whales can be found in all major oceans from the equator to sub-polar latitudes
  • The humpback whale’s lifespan is about 50 years
  • They eat mostly krill, plankton, and small fish
  • Humpback whales can consume up to 3,000 pounds of food per day
  • Females are typically longer than males, and they can reach up to 60 feet in length
  • Newborns weight about 2,000 pounds and adults can grow to be between 50-80,000 pounds

Avery Marvin: Ebbs and Flows and Puffins! July 11, 2013

NOAA Teacher at Sea
Avery Marvin
Aboard NOAA Ship Rainier
July 8 — 25, 2013 

Mission: Hydrographic Survey
Geographical Area of Cruise: Shumagin Islands, Alaska
Date: July 11, 2013

Current Location: 54° 49.6 N, 159° 46.6 W

Weather data from bridge: 8.7°C, good visibility (6-8 miles), light and variable wind, overcast

View of Bird Island Cove from tide gauge installation point
View of Bird Island Cove from tide gauge installation point

Science and Technology Log:

Today, Rosalind and I were scientists in the field, helping the ship’s crew install tidal equipment in preparation for ocean floor survey work.  This was a complex process, so we decided to walk you through it in a step-by-step question format.

What does a navigation chart show you?

The image below shows a chart of the area that we are in right now. Our first anchor point was off the north coast of Bird Island in a cove. On the chart, you can see many tiny numbers in the water areas, which represent various depths.  These depths are measured in fathoms (1 fathom=6 feet).  This depth information helps mariners stay in safe areas that are not too shallow. The charts also show known hazards such as sub-surface rocks and ship-wrecks. This chart clearly has a lot of white space, signifying many areas were never surveyed.

Shumagin survey area
Part of our survey area. Notice the white spaces around Bird and Chernabura Islands!

But wait, why are the depth numbers “fixed” on the charts? Doesn’t the water level change with the tides?

Yes! It sounds easy to say, “the water is 10 fathoms deep at this point”. However, water is subject to the gravitational pull of the moon and sun, resulting in various water levels or tides throughout the day.  So the water will not always be “10 fathoms deep at this point.” For navigational purposes, the most hazardous water level is the lowest one, so nautical charts show the depth at the low tide water level.  Depending on the location, some places have two high tides and two low tides per day (semi-diurnal) and some places have one high tide and one low tide per day (diurnal). Here in the Shumagin Islands we are on a semi-diurnal mixed tide schedule (meaning that the two highs and two lows are not the same height).

How do you measure the tides each day?

shumagin_tide_zone
Map of the Shumagin Island-Sand Point Tide Zones. Notice how the eastern Shumagin Islands are 6 minutes ahead of Sand Point.

There are permanent tide measuring stations all over the globe that provide information on how to “correct for” and figure out your local tide conditions. For our case, there is a tide station at Sand Point on Popof Island, which is west from our survey area.  Our survey area is in two zones, one which is in the same zone as Sand Point and the other which is in a different zone. Therefore, we installed a tide gauge in the latter to verify that the tidal times and heights of this zone are accurately predicted by the Sand Point values. According to the current information, it says that in the different zone the tides should occur 6 minutes before the tides in Sand Point and to multiply the heights by 0.98.

A tide gauge is a pretty cool device that works by the laws of physics. It is installed (by divers) on the sea floor near a coast-line, in relatively deep water, so that it will always be covered with water. The tide gauge uses the water pressure above to determine the depth of the water column (density of water and gravity are the important factors in making this calculation). The tide gauge stays in place for at least 28 days (one full tidal cycle), after which there is a record of the water level throughout that time period (as we were gathering data), as well as a rough idea of the tidal cycle each month, ready for comparison to the Sand Point data.

How do you know if the tide gauge is working?

To verify that the tide gauge is working, humans (i.e.: Rosalind and I), take water level  measurements (in an area close to the tide gauge) using a giant meter stick or “staff”. In our case, we recorded the average water level height every 6 minutes for 3 consecutive hours.  This 3-hour data set can then be compared to the tide gauge data set for that same time period, and hopefully they will show similar trends.  

Geiger_IMG_1279 (25)
Mike (XO) and Avery, taking water level data using the staff (big meter stick)
Tide staff
This is the tide staff we used to gather water level data for comparison to the tide gauge.
Map of the Shumagin Island-Sand Point Tide Zones. Notice how the eastern Shumagin Islands are 6 minutes ahead of Sand Point.
Graph showing the water height measurements from the tide staff and the tide gauge. Notice how they appear to be increasing at the same rate! That’s good.

What happens if the survey terrain changes over time? Will that affect the water depth?

The ocean floor is above a liquid mantle, so it is possible for there to be terrain changes and this would affect water depth measurements. Thus, as scientists, we must make sure the location of our survey area is “geologically stable”. To do this, we installed “benchmarks”. If you’ve ever been to the highest point on a mountain in the United States, you might have already seen something like this: they are bronze disks that mark important places, used by NOAA as well as other agencies. We stamped our benchmarks with the year and our station data, letter A-E (by hand! with a hammer and letter stamps!), and installed them at roughly 200-foot intervals along the coastline in what we hope is bedrock. Once they were cemented in place, we determined each benchmark’s relative height in relation to the staff using a survey instrument called an optical level – this process is also called “leveling.” At the end of the survey season, the ship will come back and re-level them. If the area is geologically stable, the benchmarks should all be at the same relative heights to one another as they were when they were initially installed. More so, the scientists will also be very pleased because their ocean depth measurements will be reliable going forward in time.

Stamping a benchmark
Stamping a benchmark
Cemented benchmark
A benchmark firmly cemented in place.
Avery cements her first benchmark :)
Avery next to her first cemented benchmark 🙂
Rosalind measuring distance between benchmarks
Rosalind measuring the distance between benchmarks

So what next?

Now that we have completed all necessary pre-survey measurements and research, we are ready to begin surveying the coastline and ocean floor.  Happy Hydro!

Personal log

It’s a pretty cool feeling to know that you stepped foot on an island that hasn’t seen human visitors in 20+ years. It was also refreshing to get off the big boat and head to shore for some science fieldwork. I learned all about tide gauge and benchmark installation.  I had several small but important tasks:

  • stamp each bronze benchmark with year and appropriate code using hammer and metal letter stamps
  • mix up cement batter and add to drilled rock hole and under benchmark disc to secure it in place for years to come (much harder than it looks because the cement was like “oobleck” and not very cooperative)
  • measure distance between each benchmark using extra long tape measure
  • take water level data using staff (big meter stick) in water every 6 minutes
Cool anemome I found!
Cool sea anemone I found!

In between tasks, I perused the tide pools for various critters. I saw a few new anemones and got a great shot of one with my new underwater camera.  I absolutely love tide pooling and could spend most of the day doing it.  I also enjoyed observing the puffins flying in and out of their cliff-side home. They tended to leave the cliff in packs probably to do some offshore fishing for herring and capelin. Upon return, presumably with a belly full of fish, some puffins would fly in large circles near their dwelling a few times before finally landing. This bewildered me. I thought, what a waste of energy! So I researched this and found out the following:  Puffins are much better swimmers than flyers and have poor maneuverability while in the air. They sometimes are involved in mid-air collisions or crash landings into rocky slopes. Thus, they “size up” their landing a few times by circling near it before finally flying directly into their vertical burrow entrance.

Their body is mostly adapted for swimming, with short rigid wings helping them to “fly” underwater, to 30+ ft. depths! They have durable bones that endure pressure changes while diving and their body tissues store oxygen. They use anaerobic respiration for long dives. To waterproof their wings, puffins rub their bill on their oil gland several times and then smear this oil all over their feathers. How cool!

We are seeing a lot of Tufted Puffins out here in the Shumigans because it is breeding season (June-August), the time when they return from lonely open waters to rocky islands to mate and raise young. Puffins are monogamous, usually having one partner for many years. Interestingly, a female puffin only lays one egg, which is incubated for around 45 days! Both parents share incubation and feeding duties. Right on! The chick then stays in the nest for around 45 days until ready to fly. I love puffins! They are not only adorable but very well-adapted creatures.

Tufted Puffin
Tufted Puffin

Fun/sad factoid: Alaskan and Canadian natives made reversible parkas out of puffin skin. When it was rainy out, they wore the feathers on the outside and in cold dry weather, they wore the feathers on the inside. It took 45 puffins to make one parka!

Rosalind Echols: Ebbs and Flows, July 11, 2013

NOAA Teacher at Sea
Rosalind Echols
Aboard NOAA Ship Rainier
July 8 — 25, 2013 

Mission: Hydrographic Survey
Geographical Area of Cruise: Shumagin Islands, Alaska
Date: July 11, 2013

Current Location: 54° 49.6 N, 159° 46.6 W

Weather data from bridge: 8.7°C, good visibility (6-8 miles), light and variable wind, overcast

View of cove
View of our anchorage from the installation point in a sunny moment.

Science and Technology Log:

Today, Avery and I were scientists in the field, helping the ship’s crew install tidal equipment in preparation for ocean floor survey work.  This was a complex process, so we decided to walk you through it in a step-by-step question format.

What does a navigation chart show you?

The image below shows a chart of the area that we are in right now. Our first anchor point was off the north coast of Bird Island in a cove. On the chart, you can see many tiny numbers in the water areas, which represent various depths.  These depths are measured in fathoms (1 fathom=6 feet).  This depth information helps mariners stay in safe areas that are not too shallow. The charts also show known hazards such as sub-surface rocks and ship-wrecks. This chart clearly has a lot of white space, signifying many areas were never surveyed.

Shumagin survey area
Part of our survey area. Notice the white spaces around Bird and Chernabura Islands!

But wait, why are the depth numbers “fixed” on the charts? Doesn’t the water level change with the tides?

Yes! It sounds easy to say, “the water is 10 fathoms deep at this point”. However, water is subject to the gravitational pull of the moon and sun, resulting in various water levels or tides throughout the day.  So the water will not always be “10 fathoms deep at this point.” For navigational purposes, the most hazardous water level is the lowest one, so nautical charts show the depth at the low tide water level.  Depending on the location, some places have two high tides and two low tides per day (semi-diurnal) and some places have one high tide and one low tide per day (diurnal). Here in the Shumagin Islands we are on a semi-diurnal mixed tide schedule (meaning that the two highs and two lows are not the same height).

What are your experiences with high and low tides? What do you notice when you go to the beach? Leave me a comment!

How do you measure the tides each day?

shumagin_tide_zone
Map of the Shumagin Island-Sand Point Tide Zones. Notice how the eastern Shumagin Islands are 6 minutes ahead of Sand Point.

There are permanent tide measuring stations all over the globe that provide information on how to “correct for” and figure out your local tide conditions. For our case, there is a tide station at Sand Point on Popof Island, which is west from our survey area.  Our survey area is in two zones, one which is in the same zone as Sand Point and the other which is in a different zone. Therefore, we installed a tide gauge in the latter to verify that the tidal times and heights of this zone are accurately predicted by the Sand Point values. According to the current information, it says that in the different zone the tides should occur 6 minutes before the tides in Sand Point and to multiply the heights by 0.98.

A tide gauge is a pretty cool device that works by the laws of physics. It is installed (by divers) on the sea floor near a coast-line, in relatively deep water, so that it will always be covered with water. The tide gauge uses the water pressure above to determine the depth of the water column (density of water and gravity are the important factors in making this calculation). The tide gauge stays in place for at least 28 days (one full tidal cycle), after which there is a record of the water level throughout that time period (as we were gathering data), as well as a rough idea of the tidal cycle each month, ready for comparison to the Sand Point data.

How do you know if the tide gauge is working?

To verify that the tide gauge is working, humans (i.e.: Avery and I), take water level  measurements (in an area close to the tide gauge) using a giant meter stick or “staff”. In our case, we recorded the average water level height every 6 minutes for 3 consecutive hours.  This 3-hour data set can then be compared to the tide gauge data set for that same time period, and hopefully they will show similar trends.  

Tide staff
This is the tide staff we used to gather water level data for comparison to the tide gauge.
Map of the Shumagin Island-Sand Point Tide Zones. Notice how the eastern Shumagin Islands are 6 minutes ahead of Sand Point.
Graph showing the water height measurements from the tide staff and the tide gauge. Notice how they appear to be increasing at the same rate! That’s good.

What happens if the survey terrain changes over time? Will that affect the water depth?

The ocean floor is above a liquid mantle, so it is possible for there to be terrain changes and this would affect depth measurements. Thus, as scientists, we must make sure where our survey area is “geologically stable”. To do this, we installed “benchmarks”. If you’ve ever been to the highest point on a mountain in the United States, you might have already seen something like this: they are bronze disks that mark important places, used by NOAA as well as other agencies. We stamped our benchmarks with the year and our station data, letter A-E (by hand! with a hammer and letter stamps!), and installed them at roughly 200-foot intervals along the coastline in what we hope is bedrock. Once they were cemented in place, we determined each benchmark’s relative height in relation to the staff using a survey instrument called an optical level – this process is also called “leveling.” At the end of the survey season, the ship will come back and re-level them. If the area is geologically stable, the benchmarks should all be at the same relative heights to one another as they were when they were initially installed. More so, the scientists will also be very pleased because their depth measurements will be reliable going forward in time.

Benchmark gear
This is the benchmark-stamping set-up.
Rosalind chiseling
Rosalind chiseling away at the rock to ready it for benchmark installation.
Rosalind and Avery with cement
Rosalind and Avery cementing a benchmark in place for posterity.
Cemented benchmark
A benchmark firmly cemented in place.
Rosalind holding stick
Rosalind holding the level rod for the benchmark leveling process. It turns out that it is incredibly difficult to hold 12 feet of leveling rod level.

So what next?

Now that we have completed all necessary pre-survey measurements and research, we are ready to begin surveying the coastline and ocean floor.  Happy Hydro!

Personal log

One of my favorite parts about this particular activity was exploring the coastal wildlife along the way. A Harbor Seal spent a good portion of the day swimming near by and keeping an eye on what we were doing. Unfortunately, every time I tried to get closer for a picture he ducked under water. He was clearly very curious, though. No doubt the installation of the equipment seemed rather bizarre.

Installation point
This is a view of the installation point we used for the tide gauge. You can tell that the tide is low because of all the exposed animal and plant life at the base of the rocks.

Being on the rocky outcropping where we installed the tidal gauge and the beach nearby reminded me a great deal of my childhood. From the washed up bull kelp still clinging to a barnacle (sometimes still alive) to the hermit crabs scurrying away from my hand in tide pools to the brightly colored sea anemones untucking as the tide came in, it brought back a lot of fond memories and definitely re-inspired my childhood enthusiasm for exploring nature and learning about biology by experiencing it. It also brought back that sense of heightened physical awareness as I scrambled from barnacle-covered rock to barnacle-covered rock, trying to avoid the slippery foot placements that would inevitably lead to lengthy gashes on my hands. All is well. I returned from my beach adventure in one very intact piece, slightly rosy-cheeked despite the overcast conditions.

Sea anemone!
An open sea anemone. They also come in red, orange, pink, and purple!
Wildlife!
Sea Anemones, barnacles, and other rock-dwelling critters exposed at low tide.

Aside from that, as someone who loves food and eating, the Rainier has treated me very well so far. We have some wonderful stewards and cooks, who do a far better job feeding 50+ people than I do feeding one or two. Every meal includes several gourmet options, including stuffed peppers, chicken or tofu stir fry, braised beef, and countless other delicious things. And there is dessert at every meal. And a freezer full of ice cream. No wonder the crew on the Rainier seems so happy!

Kaci Heins: September 21-23, 2011

NOAA Teacher at Sea
Kaci Heins
Aboard NOAA Ship Rainier
September 17 — October 7, 2011

NOAA Ship Rainier

Mission: Hydrographic Survey
Geographical Area: Alaskan Coastline, the Inside Passage
Date: Friday, September 23, 2011


Weather Data from the Bridge

Clouds: Overcast
Visibility: 10 Nautical Miles
Wind: 25 kts
Waves: 1- 2 feet
Temperature
Dry Bulb: 10.3 degrees Celsius
Barometer: 1002.6 millibars
Latitude: 55 degrees North
Longitude: 133 degrees West

Science and Technology

Rainier Skiff Boat

Now that there is a small window of clear weather I am able to go out on one of the small boats called a skiff.  This boat holds about 8 people max and is mainly being used to move people and equipment around to the different stations.  The night before I was scheduled to leave I learned that my task on this outing was going to be reading the tide staff every six minutes for 3 hours.  I know the initial reaction might be, “Why would you want to do that?”  Well, it is actually really important for the data that we are collecting.  When the equipment (primary benchmark, tide gauge, tide staff, orifice, etc.) was placed on Block Island this allowed the scientists to be able to know what the actual water levels would be for the launches when they head out. This in turn, is important because the height of the water levels will affect the data that is being collected on the launches (survey boats).  The first few hours started giving us pretty good data, but then we stopped getting anything at all.  We had been hit by a storm so numerous scenarios were being brainstormed so we could be prepared for anything that we might find when we got there to fix the problem.

Garmin Route to Block Island Courtesy of Todd Walsh

We traveled from the Rainier to Block Island, which was about 19 miles away.  When we got there the tide staff was in good shape and even the antennas and GPS looked good.  However, upon further inspection they found that there were glitches in the software files that had made it stop collecting data.  Once they got it going again, my partner Starla, and I went straight to work collecting the high and low wave of the tide.  We then used this data to calculate the mean (average) of the two.  We had to collect this data every six minutes for three hours because that is the same data that the tide gauge is collecting.

Tide staff at Block Island

We had to use GPS time–which was the same as the tide gauge–and not our own watches. This is because we needed the same time stamp for the data, which allows the scientists to see that the data was collected at exactly the same time.  Scientists can then look to see if the data we collected and the data the tide gauge collected are the same or if there are errors.  Then, they can see if it was human error or if something is still wrong with the tide gauge.  These first three hours were very important for the data collection, but the scientists will continue to monitor the station every three to four days for one hour throughout the month to make sure it is collecting data properly.

Mrs. Heins Taking Tide Staff Measurements

As we collected the data, one of us would watch the clock while the other would very intently watch the tide staff.  Once it would come to the time we would have to collect the data she would say “Mark!” and that would be my cue to note the high and low of the wave against the tide staff.  I would tell her my observations up to four digits, such as 1.967 meters.  However, because we would use quick observations to collect our data, our precision would probably be only to three significant figures. Significant figures are digits of a number that carry meaning and factor  into its precision. Starla would record the data and then we would wait six minutes until the next time to make our observations. When we were done, we downloaded the data from the tide gauge, packed up the skiff, and head back to the Rainier. Overall, it was a really great day being able to collect this important data and contribute to the mission of the ship.

Heading Back to the Rainier

Personal Log

Calculating Radar Ranges on a Nautical Chart

Math, math everywhere!!  Since the first day I have been on the Rainier I have seen math being used all day, every day.  Even though I don’t specifically teach math I do integrate it within science and social studies.  However, I have heard from students, “Why do I have to learn this?” in regards to their math homework.  There isn’t always enough time in the day to give a thorough explanation of how different math skills are used in the real world.  However, from my past NASA experiences and now with NOAA on the Rainier, I am here to tell you that once you enter the real world, especially if you enter a science, math or engineering field, then you will be immersed in math.  It will become a part of your daily routine without you really realizing it.  One place where math is used constantly, and is also one of my favorite places on the ship, is the bridge.

Math is used in navigation, such as setting a course, calculating distances, speeds, and times.  I also got some practice with calculating radar ranges, which can give the officers their location based off of 3-4 points of land nearby.  GPS is being used all day, every day and there are multiple GPS systems in case one fails.  Again, the officers use this information in their calculations throughout the day while we are at sea.  When I have been collecting weather data on the bridge math is being used to calculate the wind speed and direction.

Finding an Azimuth

Then there are conversions being calculated because some of the charts are in meters, some are in feet, and some are in fathoms.  A fathom is used more for deeper water because 1 fathom equals 6 feet.  Because these are dealing with depths it is very important to make sure the conversions are correct so that the ship stays safe.  Then of course there is math used in other ways on the ship.  For example, the Executive Officer (XO) has to work with the ship’s budget, the cooks work with measurements in the galley, and the scientists work with math formulas as they process the data in their projects.

Overall, I highly encourage my students and any other young minds that are reading this to do your best in math and ask for help if you need it.  It can be an intimidating subject area at times, but if you want to work for NOAA, be a scientist, or engineer then it will be an important part of your job.  Once you have an idea of what kind of job you want to have when you get older, try to find out what kind of skills you need to have and start early.  See how the math is used in the real world, the job you are interested in, and learn how to have fun with it!

Student Questions Answered!

Animals Seen

Sea Lion

Whales (not sure of the species)

California Sea Lion

Moon Jellyfish

Question of the Day

Rita Larson, August 12, 2009

NOAA Teacher at Sea
Rita Larson
Onboard NOAA Ship Rainier
August 10 – 27, 2009 

Mission: Hydrographic Survey
Geographical Area of the Cruise: Kasitsna Bay, AK
Date: August 12, 2009

Weather Data from the Bridge 
Latitude: 59° 28.515′N Longitude: 151° 33.54′W
Sea Water Temperature: 9.4°C
Air Temperature: Dry Bulb: 14.4°C (58°F); Wet Bulb: 12.2°C (55°F)
Visibility: 10 miles
Wind: 06

The skiff RA-8 being launched from NOAA Ship Rainier.
The skiff RA-8 being launched from NOAA Ship Rainier.

Science and Technology Log 

Last night (Aug 11, 2009) the P.O.D (Plan of the Day) was posted and I found out that I was assigned to work with the Survey Team. We would go out on the skiff identified as RA-8.  We had a special guest that came with us today, Mr. Randall, from the NOAA Headquarters located in Silver Spring, Maryland was in Homer Alaska, so we drove RA-8 to Homer, Alaska to pick him up. Then we proceeded to Bear Cove to complete our main mission, which was to observe the tides and complete the leveling of the remote tide gauge. NOAA uses tide gauges to verify long-term assessment of sea level changes and establishes the vertical datum, or frame of reference, for their nautical charts. Mr. Randall was retrieving a GPS (Global Positioning System) unit that was planted in Bear Cove the previous day to collect data.

Our crew consisted of Matt Abraham, our coxswain, was responsible for driving the open skiff (RA-8). Our hydrographer in charge was ENS Schultz; she surveyed Bear Cove and retrieved the data from the tide gauge. Manuel Cruz and Tony Lukach were responsible for holding the leveling rods to help complete the survey. My responsibility was to write the data given to me and record it on the leveling sheets and find the difference between each measurement. Mr. Randall also worked with us throughout the day. While surveying we used a three-wired level that sits on a tripod, level rods, measuring tape, turtles, pencil, and a calculator.

Personal Log 

Looking through a three wire level.
Looking through a three wire level.

I was so excited about this mission since it was my first one. I was very cold in the morning since we were a little bit wet from the spray of the ocean, even though I was dressed very warmly. By the afternoon I was only wearing a t-shirt and jeans. The scientists were telling me the last time they were at Bear Cove they actually saw a bear. So, I was looking around constantly to keep an eye out for them. At one point of the day I went with ENS Schultz to collect the initial tide measurements from the tide gauge and check the flow of the nitrogen gas to make sure it was operating smoothly. Little did I know that I had to climb a wooded hill to help collect this data. One has to be in great physical shape to perform these types of tasks. It was unbelievable to see such sophisticated equipment in such a remote area.

After observing these remarkable scientists doing their jobs in the middle of a mosquito-infested area, I applaud everything they do. I felt comfortable and I felt safe in their care. They are all so knowledgeable in their fields. One can really sense the teamwork that is needed for all the missions NOAA  expects from them. I am proud and honored to be a part of the project called Hydropalooza, which provides a deeper understanding of Alaska’s Kachemak Bay.

New Term/Phrase/Word:  Turtles in surveying are not animals. They are used as half way marks from the benchmark item to the surveyor. The ones we used were round and heavy with a silver handle on them. They are heavy for a reason, so they do not move once they are placed on the ground. Surveying is very important to this mission since the measurements must be within 2.5mm.

Animals Seen Today 
Puffins and Sea Otters

Collecting data from the tide gauge in Bear Cove
Collecting data from the tide gauge in Bear Cove

larson_log1e larson_log1d

As we were bringing Mr. Randall back to Homer we saw this glacier in the distance.
As we were bringing Mr. Randall back to Homer we saw this glacier in the distance.

John Schneider, July 11, 2009

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

Mission: Hydrographic Survey
Geographical Area: Kodiak, AK to Dutch Harbor, AK
Date: July 11, 2009

Position 
Sheet L – Shumagin Islands

Weather Data from the Bridge 
Weather System: Overcast
Barometer: 1021.4
Wind: mild and veering*
Temperature: 12.1º C

Science and Technology Log 

One of the Fairweather's launches
One of the Fairweather’s launches

Today I got to go out on launch 1010.  The two primary launches on Fairweather are 29-foot diesel-powered (Caterpillar) single-screw aluminum boats.  I was real surprised to find that 1010 is 35 years old!  It’s in great shape.  Survey equipment on board includes the multi-beam echo sounder, computers, DGPS (Digital GPS gives positional accuracy to about 6 inches!) radar, radios and Iridium satellite telephones.  For “creature comforts” there’s a microwave and mini-fridge as well as a very efficient heater/defrost system.  Oh, by the way, there are no heads on the launches. (FYI – a “head” is marine-speak for a bathroom!)

Here I am on the launch monitoring all the data that’s being collected
Here I am on the launch monitoring all the data

Knowing this in advance, I didn’t have coffee or tea or a big breakfast. Turns out that when “nature calls” the rest of the crew goes in the cabin, closes the door, and you go over the side! Seems gross at first and then you realize that the 30 and 40 ton whales go in the ocean too (besides, it’s biodegradable!) The launches are carried on the boat deck (E-deck) in custom Welin-Lambie davits made for each launch. Welin-Lambie is a company over 100 years old and made the davits for a few ships you may have heard of – the British Royal Yacht Britannia, the Queen Elizabeth 2 cruise ship and oh, yeah, the RMS Titanic!  The cradles are self-leveling so when the Fairweather is in heavy seas they remain upright and stable.  The picture on the left shows 1010 in its cradle. When it’s time to launch the boat, the securing devices are released, the boat is swung out over the side and two >3 ton winches lower the launch to the rail of D-deck.  There it is boarded by the crew and loaded with the needed gear for the day.  It is then lowered into the water and sent on its way.

Once we got to the area of our polygon (I’ll explain polygons later in the week) we began acquiring data by “mowing the lawn” – the process of sailing back and forth across a defined area collecting soundings1 (bottom depths.)  In every polygon we conduct a CTD cast (CTD = Conductivity Temperature Density.)  These three parameters determine the speed of sound in the water and are used to accurately calibrate the soundings. Once we had been working for a while with me observing – and asking what must have seemed like unending questions – PIC2 Adam Argento and AST3 Andrew Clos guided me to monitoring the data being acquired. As you can see on the left there are 4 monitors all running software simultaneously.  The picture on the right shows the keyboard and mice. The mouse in my right hand controls the windows on the three screens to the right which are data displays of received info. The left mouse controls which data are being acquired.

After a long day on the launch, it was great to see the Fairweather on this rainy day.
After a long day on the launch, it was great to see the Fairweather on this rainy day.

After lunch the coxswain4 (“coxin”) – AB Chrissie Mallory – turned the helm over to me to steer.  My first leg was headed North.  The positional displays on the Fairweather and its launches all have North being at the top of the displays.  (This is called – logically enough – “North Up”.)  I rocked! If I had to move off to the right a little, I turned right.  Need to move left, turn left. There’s a little delay between when you turn and the position as displayed on the screen.  Well, we got to the top of the section and turned around to head South.  I needed to adjust a bit to the right, so I turned right . . . BUT . . . the boat is now oriented 180º from the prior run.  So in turning right, I actually made the boat go left on the screen!  Oh NOOO!!! So I overcompensated the other way.  Then had to un-overcompensate . . . and so on.  I’m sure when they downloaded the data back on the Fairweather they were wondering what the h*** was going on. Eventually I got the hang of it and didn’t do too badly after a while, but I have a much greater appreciation of what appeared to be really simple at the outset.

After a successful 8+ hours out (by the way, our lunches contained enough food for 6 people!) we headed back to the Fairweather about 15 miles away.  To see her after a day out kind of felt like seeing home after a long day out. To the unaware, the ship looks like a mish-mash of all kinds of gear all over the place, but it’s remarkably organized.  The reason for the appearance is that the ship is capable of so many tasks that the equipment is stowed in every available space.  Fairweather is capable of deploying 7 small boats and operating independently of all of them in coordinated tasking!  I’d love the opportunity to take a class of students for an all-day field trip aboard and could do so without ever leaving the dock – there’s so much on board!

A launch returning to the Fairwweather
A launch returning to the Fairwweather

As you can see in the photo of the Fairweather above, there are two large white inflated “fenders” hanging over the starboard side.  This is where we’ll be tying alongside. (I took the next 3 shots from the Fairweather as 1010 approached on a different day.) As the launch approaches, the person on the bow will throw a line to the forward line handler.  Notice there’s not a whole lot of room up there as well as the extended arm ready to catch the line.  That bow line has a mark on it which lets the line handler on Fairweather know where to temporarily tie off the line.  Then the stern line is then thrown to another line handler. Once the launch is positioned properly (no easy task in rolling seas) the hoists are lowered to the launch where they are clamped onto lifting eyes.  Each of the clamps on the boat falls5 weighs close to 40 pounds – that’s why in deck ops everyone wears hardhats – and is controlled by both the winch operator and two more line handlers using “frapping lines6.” (in the picture to the left, as the launch approaches, you can see the boat falls, clamps and frapping lines.)  Once the clamps are secured, the launch is lifted to the deck rail and the crew gets off, and the launch is lifted back to its cradle.

Piece of cake!  Realize, however, that this simply and cleanly executed maneuver, requires: On the Fairweather: 4 line handlers The Chief Bosun 1 or 2 surveyors The bridge crew to maintain position (at least 2 people) 2 or 3 deck personnel to unload gear from the launch A Chief Scientist to task the launch The chefs to feed the launch crew On the launch: Person in charge Coxswain 1 winch operator From 14 to 16 people, all working together.  On January 1, 2008, the Fairweather was authorized to paint a black letter “S” on both sides of the ship indicating that she had gone 433 consecutive days without any injuries.  Considering the environment in which Fairweather works and the tasking which requires constant deployment and retrieval of heavy equipment, the “Safety S” is a reflection of her crew and officers.

Personal Log 

What a great day!

Vocabulary 

  1. Soundings – depths measured
  2. PIC – Person In Charge
  3. AST – Assistant Survey Technician
  4. Coxswain – (<O.Fr. coque “canoe” + swain “boy”) Individual who steers a small boat or launch
  5. Boat falls – the lines used to raise and lower boats from a davit
  6. Frapping lines – Lines used to control the boat falls

By the Way 

It’s time to do some laundry!!!  The laundry room is on D-Deck just forward of the fantail.

See you all tomorrow! 

It’s laundry day!
It’s laundry day!

John Schneider, July 8, 2009

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

Mission: Hydrographic Survey
Geographical Area: Kodiak, AK to Dutch Harbor, AK
Date: July 8, 2009

Position 
Small boat/launch operations vicinity; Herendeen Island (Shumagin Islands Group)

Weather Data from the Bridge 
Wind: light & variable
Temperature: 12.7ºC
Sea State: 1 foot

National Ocean Service Benchmark
National Ocean Service Benchmark

Science and Technology Log 

Today I’ll be heading out on the Ambar (an aluminum hulled inflatable) to check on a tide gauge off Herendeen Island.  It might get chilly being off the Fairweather, but the weather has been fantastic since we left. Waves <1 foot, winds below 5 or 6 knots.  Weather actually got better as we went to the tide station.  (I’ll try to get a good shot of each of the launches.) The tide station is a remarkably simple in concept, yet a terribly complex operation to execute. A month ago, Fairweather personnel installed a tide station on Herendeen Island. This involved sending a launch to the island where personnel did the following setup work:

The tide gauge interface being downloaded to a weather/shockproof laptop computer
The tide gauge interface being downloaded to a weather/shockproof laptop computer
  1.  Drill a 1/2 inch hole 3” deep into a solid piece of granite and set a bronze bench mark into it.
  2. Drill 3 more holes into a huge granite boulder at the water’s edge. Construct, on that boulder, a vertical tide gauge with markings every centimeter, ensuring that the bottom of the gauge is both lower and higher than the tide should go.
  3. Precisely and accurately determine the height of the benchmark in relationship to the heights on the tide gauge.
  4. Send a diver down below the lowest tide levels and install a nitrogen-fed orifice connected to a hose and secure it to the sea floor.
  5. Connect the hose to a pressurized tank of nitrogen on shore.
  6. Install a solar power panel near the station with a southern exposure.
  7. Install the data acquisition interface. This piece of equipment forces a single nitrogen bubble out of the orifice every six minutes (one-tenth of an hour) and measures the pressure it takes to release the bubble which is then used to calculate the depth of the water (as a function of pressure.)

Collected data are automatically sent by satellite to NOAA. A month later, the survey team re-visits the site and performs a series of 10 visual observations coordinated with the automated sequences of the nitrogen bubble data recorder.  These visual observations are then compared to the automated data acquired.  If their statistical differences are within accepted parameters, the data are considered valid and will be used further.  If not, the data are discarded and collection is re-started. 

It's a little weird to see the Ambar leave after dropping us off on an island that has seen very few footprints!
It’s a little weird to see the Ambar leave after dropping us off on an island that has seen very few footprints!

Not only is the process painstaking, but the technology and Research & Development needed to design the equipment must have been extremely difficult. However, given the amount of our nation’s dependence on marine commerce and movement of goods, it is time and effort more than well spent. Once we returned to the ship, I was able to lend a hand on the fantail (that’s the aft area of the deck where a LOT of work gets done) where the survey team was collecting samples of the ocean bottom.  Bottom sapling is done at specific locations proscribed by NOAA guidelines for coastal waters.  It is important for mariners to know the type of bottom in an area in case they need to anchor or engage in commercial fishing. 

Bottom samples are collected using a Shipek Grab.  This 130-pound tool captures a 3-liter sample of the bottom. The scoop is spring loaded on the surface and when it strikes the bottom a very heavy weight triggers the scoop to close, picking up about 1/25 of a square meter of bottom. Bottom characteristics are then recorded with the position and will eventually be placed on nautical charts.  Sometimes even small animals get caught in the grab. Today we saw brittle stars, tube worms and a couple of little crabs.  However, the biggest surprise to me was finding numerous small pieces of CORAL in the samples!  I certainly did not expect to see coral in ALASKAN waters!

Personal Log 

A piece of coral on a pebble.  (It's on a 3x5 file card for scale.)
A piece of coral on a pebble. (It’s on a 3×5 file card for scale.)

Lest you think that it’s all work and no play, we anchored tonight after a 12 hour+ work day.  With sunset at around 2330 hrs (11:30) there was still time for some fishing (nothing was kept but we caught a couple small halibut) and movies in the conference room.  There are movies aboard almost every night as well as closed circuit images from 4 areas of the ship.  I’ve also started taking pictures of the menu board every night but won’t post all of them because of space limits on my file size – besides, you all simply wouldn’t believe how well we are fed on the Fairweather. Just as an example: how does blackened salmon wraps sound for lunch??? Oh yeah!!! (You have permission to be jealous!)

Coming back, the Fairweather, after being out of sight from the Ambar, is a welcome sight!
Coming back, the Fairweather, after being out of sight from the Ambar, is a welcome sight!

Animals (or other cool stuff!) Observed Today 

Saw a whale in the distance, quite far off, just before lunch. Two seals a couple hundred meters aft of the port quarter. While at the tide station we saw two whales’ spouts near the shoreline, one seal poked his big ol’ head up from the kelp bed and checked us out a couple of times, saw a bunch of loons, cormorants and puffins, and while at the tide station, Dave Francksen (a very helpful member of the survey team) caught sight of an octopus. 

This octopus was about 2 feet across from tentacle-tip to tentacle-tip and changed color when it got over the spotted light-colored rocks.
This octopus was about 2 feet across from tentacle-tip to tentacle-tip and changed color when it got over the spotted light-colored rocks.

Questions for Your Investigation 

What phylum and class are octopi?  Are Brittle Stars?

What “day shape” does the Fairweather display when anchored?  When conducting survey operations?

What do you call the kitchen on board a vessel?

Linda Armwood, April 29, 2006

NOAA Teacher at Sea
Linda Armwood
Onboard NOAA Ship Fairweather
April 25 – May 5, 2006

Mission: Hydrographic Survey
Geographical Area: Aleutian Islands, Alaska
Date: April 29, 2006

Weather Data from Bridge 
Visibility: 10 nautical miles (nm)
Wind direction: 200 °
Wind speed:  15 kt
Sea wave height: 1 ft.
Swell wave dir: 280
Swell wave height: 2-3 ft.
Seawater temp: 7.2
Sea level pressure: 1016.6mb
Present weather: Overcast
Temperature:  °C~ 8.2dry/6.5wet

Science and Technology Log 

My assignment today was to work with the benchmark descriptions and level run team.  The responsibility of the team is to accurately and completely describe the benchmarks.  The description must include the following items:

  • directions for location
  • exact location relative to other structures including the tide gauge
  • sketch of location
  • latitude and longitude
  • above datum of tabulation in meters
  • date of establishment/recovery
  • photograph of benchmark
  • statement that benchmark disk is flush in raised concrete

The team is also responsible for completing the level run assignment.  The purpose of the level run is to level the primary benchmark to the staff stop.  This procedure provides the elevation of the staff stop. In helping with the level run, I assisted the Tides Director in the recording of rod readings. These measurements are read in three parts: top thread, middle thread and bottom thread.  Ideally, thread intervals should be equal.  However, if the thread intervals are not equal, they must be within 2 to be an acceptable reading.  Many of our readings were acceptable upon the first recording.  For the few readings that were not acceptable, the software in the I-Pod associated with the 3 stadia leveler would indicate as such.  Readings were redone accordingly.

In addition to providing assistance to the Tides Director as a recorder, I participated in holding the rod at benchmark locations for level readings.  The indication that the rod would be level is when the surveyor succeeds in moving the rod so that the bubble inside the gauge would sit on the center circle. The tide staff observation was my third assignment for the day.  The completion of these observations provides you with the elevation of your orifice to your staff stop. The tide gauge is located on the pier leg facing the benchmarks.  The boat was placed in a vantage spot that enabled a survey tech and I to monitor and record the tide height every 6 minutes for three hours.  This recorded data would later be compared to the data received by the tide gauge set-up on the pier.

Personal Log 

It was great to get out of the bitter, cold, sleeting weather conditions to the warmth of the ship. The food on the FAIRWEATHER is absolutely delectable!

Question of the Day 

Environmental Science and Geospatial Semester Students 

In which two months are the largest tidal ranges?

Mrs. Armwood

Linda Armwood, April 28, 2006

NOAA Teacher at Sea
Linda Armwood
Onboard NOAA Ship Fairweather
April 25 – May 5, 2006

Mission: Hydrographic Survey
Geographical Area: Aleutian Islands, Alaska
Date: April 28, 2006

Weather Data from Bridge 
Visibility: 10 nautical miles (nm)
Wind direction: 190 °
Wind speed:  13 kt
Sea wave height: 1 ft.
Swell waves dir: 310
Swell waves height: 2 ft.
Seawater temp: 7.3
Sea level pressure: 1012.4mb
Present weather: Mostly cloudy
Temperature:  °C~ 6.5dry/5.0wet

NOAA divers preparing to install a tide gauge at Noyes Island, AK
NOAA divers preparing to install a tide gauge at Noyes Island, AK

Science and Technology Log 

The project’s first priority for the day was to get the tide gauge installed and to set tidal benchmarks.  The tides party consisted of three onshore crews: the reconnaissance and planning team; the benchmark recovery and installation team; and the dive and install team.  I was assigned to the dive and install team boat in order to observe the divers install the tide gauge. I did not observe the underwater installation below the pier; however, the secure installation of the above water equipment was a major undertaking!  The tide gauge installation involves the proper placement of the following items:

  • satellite antenna
  • gps antenna
  • hydro gauge
  • solar panel
  • 12-volt battery
  • nitrogen cylinder
  • nitrogen regulator

I assisted in drilling with the benchmark recovery and installation team.  The historic benchmark was located about 15 feet from the low water line and the next four benchmark locations were set at 200 feet apart from one another in somewhat of a straight line from the historic benchmark.  Benchmarks are important because they represent permanent marks of the land leveling system.  The tidal gauge will automatically read water pressure which it then converts to depth every six minutes over the next 30 days in order to determine the constituents of the tide-generating force. Determining these constituents allows the survey technicians to form possible hypotheses related to ranges, heights, rates and future directions of tides.

Ensign Matthew Glazewski drills to establish a benchmark on Noyes Island, AK.
Ensign Matthew Glazewski drills to establish a benchmark on Noyes Island, AK.

Personal Log 

At the time of this writing, the weather was as stated above; however, during the tides party the weather was miserable with intermittent showers of sleet followed by sunshine and overcast.  The kindness extended to the crew by the Noyes’ Island caretaker will be remembered.

Question of the Day 

Environmental Science and Geospatial Semester Students 

Give some possible non-human factors that may have an effect on the decision-making of tide gauge location.

Mrs. Armwood

The Tidal Party recovered this historic benchmark recovered from Noyes Island, AK
The Tidal Party recovered this historic benchmark recovered from Noyes Island, AK

James Miller, August 22, 2005

NOAA Teacher at Sea
James Miller
Onboard NOAA Ship Rainier
August 13 – 27, 2005

Mission: Hydrographic Survey
Geographical Area: North Pacific, Alaska
Date: August 22, 2005

Location: Anchored in Fish Range Bay; north of Mitrofinia Island
Weather: Sunny, low 70’s
Wind: variable
Seas: 1-2 foot swell
Itinerary:  Working in Fish Range Bay area for couple of days

Science and Technology Log 

Due to the deteriorating weather forecast for the entire area around Mitrofania Island we are packing up and moving out.  There were two things that needed to be done today. First, a tide gauge that the crew installed on Mitrofania earlier in the season had to be removed.  The gauge sent tide information via satellite to a facility on the mainland.  Second, the differential global positioning system (DGPS) that was also installed on the Island earlier in the season had to be removed.  The DGPS was installed to enhance GPS signals when launches are surveying in the area.

I was assigned to help break down the DGPS with two officers and a survey technician. We headed out early in one of the skiffs for the island.  The DGPS consists of a tall antenna mounted on aluminum framing which is supported by lines tied off to stakes in the ground. It also has a watertight box that acts as the main processor for transmitting and receiving.  The processor is powered by six 12v car batteries, which get charged by a series of solar panels. Soon after being dropped off we realized we all forgot to bring bug dope, and soon after that the bugs were swarming.  It’s amazing the motivational power of flying, pestering insects.  We had the station apart and lugged down to the beach in under an hour.  Unfortunately the amount of gear and people exceed the capacity of the skiff, so it required more than one trip.  I drew the short straw along with one of the officers to wait on the island for the skiff to return.  It took about an hour so we did a little treasure hunting along the beach at the high tide line.  Earlier in the season, some of the crew found antique fishing trap floats made of blown glass.  I’m unsure of how old they are, but let’s just say very.  We didn’t find anything as interesting.

Personal Log 

I’m sorry to be leaving Mitrofania Island, partly because it is so beautiful, and also because it marks the end of the work for this leg of the trip.  We got underway for Chiginigak Bay around 4:00pm to basically run from the oncoming storm.  The travel time was about 8 hours.  The seas had already started to build when we left. For the first half of the trip we were traveling with the seas, which made for a smoother ride, however, we had to turn broadside (parallel) to the seas for the second half. When running broadside to the sea the ship pitches from side to side at pretty steep angles. I was typing up some logs in the computer room when all the books and games on the shelf came tumbling down, what a mess.  Anyway, it certainly wasn’t as bad as we anticipated and we arrived in the bay some time around midnight.

Before bed I went up to the bridge to see how the ship was handling in the seas.  One of the newer officers to the ship gave me some more navigation lessons, which was cool.

Sleeping hasn’t been a problem, even with the constant noise of the engines and rolling of the ship. In fact, I sleep deeply and have to drag myself out of bed in the morning. My cabin doesn’t have a porthole so NO light gets in.  It could be the middle of the day and I wouldn’t know it.

Despite all the fun I’m having, I have to say I really miss my home and family.  I give the crew a lot of credit for doing this all year long.  One of the crewmembers said that longing for home is a great feeling, it keeps you going, and that’s why you can’t make the ship your home.  Seems like good advice for newcomers on the ship.

JoAnne Kronberg, July 19, 2005

NOAA Teacher at Sea
JoAnne Kronberg
Onboard NOAA Ship Rainier
July 12 – 22, 2005

Mission: Hydrographic Survey
Geographical Area: North Pacific
Date: July 19, 2005

Weather Data
Waves: 8ft during the day diminishing to 6 ft in the evening
Winds:  NW 25-39 knots

Science and Technology Log

We arrived at Mitrofania Island at about 5:00 am and anchored in Cushing Bay.  Our mission today was to do a Tide Station Installment.  The National Water Level Observation Network operates 175 continuous observatory stations in the U.S. coastal zone and the Great Lakes. All are equipped with satellite radios.  Of course, a Tide Station would only be placed in the coastal areas that are affected by tides.  Water Level Stations operate in the Great Lakes.

We had to replace the Tide Station in Cushing Bay.  The sensor that is installed is called a Bubbler Orifice. It is anchoring to the bottom of the bay and is powered by a long tube that is filled with Nitrogen gas.  Two divers went down to anchor the Bubbler and attach the tube. Meanwhile, other people in another launch were setting up a Tide Staff.  A Tide Staff is just a long stick that is marked with levels like a yardstick.  The Tide Staff has to be set up to correspond with the Bench Marks that have been already determined.  The Bench Marks may be located at different sea levels.  Both the Bubbler Orifice and the Tide Staff have to be at the same sea level to be accurate.

After the Bubbler Orifice is established and the Tide Staff is set up, we started taking the readings from these two sources. Readings were taken every 6 minutes for a period of one hour. If the readings after an hour are not the same, then the Bubbler Orifice has to be adjusted.

The data collected by the Bubbler Orifice is transmitted to the Data Collection Platform.  In turn, this information is transmitted to no less than four satellites and to the National Geodetic Survey.

The work today has taken most of the day.  We will stay anchored in Cushing Bay tonight. Early tomorrow morning, Wednesday, we will start cruising toward Chiniak Bay.

It was a very educational day and the weather was fantastic.  Thank you for this opportunity.

JoAnne Kronberg Teacher-at-Sea

Leyf Peirce, July 7, 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 7, 2004

Time: 10:15
Latitude: N 57°31.730
Longitude: W 154°58.325
Visibility: 10 + m
Wind direction: 250
Wind speed: 18 knots
Sea wave height: 2 – 3 feet
Swell wave height: 2 – 4 feet
Sea water temperature: 10.6 °C
Sea level pressure: 1020.1 mb
Air temperature: 12.2 °C
Cloud cover: 2/8

Science and Technology Log

I talked more with P.S. Shyla Allen about how the multibeam echo sounders work on the ship to gather data about the depths of the ocean. Both the RAINIER and the launch ships use the following method to gather data. All of these vessels use echo sounders with anywhere from 120 to 240 beams that scan the ocean floor. The following diagram illustrates how this is done:

Peirce 7-7-04 Fig1
Figure 1: Multibeam Echo Sounding

Here, “z” is an echo sounding two-way travel time beam, and the multibeams are spread over the footprint distance of “f”. The size of the sound footprint, “f”, depends on the depth at which the measurement is taken, “z”. The greater the depth is, the greater the footprint is. However, the greater the footprint is also means less accuracy on the outer edges of the footprint. Therefore, the ship will run a “mowing the lawn” pattern across the given section to get desired overlapping of data:

Peirce 7-7-04 Fig2
Figure 2: Mowing the Lawn pattern

The width of these lines is determined by: width of x = 3 * z. By using this rough equation, the ship will be able to overlap the areas of least accuracy, i.e. the areas on the outer range of the footprint:

Figure 3: Ship running mowing the lawn pattern so the footprints overlap.

From this data, the depth and contours of the ocean floor can be determined. I also asked P.S. Shyla Allen about the problems and sources of error associated with this data collection. She responded by detailing three main issues that must be corrected when cleaning the data, i.e. the data must undergo three main correction factors before accurate readings can be analyzed. These three factors include: a) tide changes, b) sound velocity, c) the motion of the ship and GPS positioning. To correct for tide changes, the researchers must have accurate readings of the tides. Tide gauges are installed along the coastline at various points, and all readings are reduced to Mean Lower Low Water (MLLW). This basically gives the average of the lowest possible depth at a given location. To correct for sound velocity changes, which is the most important correction factor dealt with, researchers take measurements of water temperature and salinity level at the given depth reading. For every change of 1 ppm in salinity, there is a change of 3 m/s in sound velocity. Therefore, salinity is perhaps one of the most important factors. Finally, the motion of the ship and GPS position need to be corrected for. This includes correcting for the pitch, roll, and gyration of the ship as well as error in the GPS system. Because the ship uses Differential GPS (DGPS), this error is already accounted for. However, for the pitch, roll, and gyration of the ship, two antennas are used to on the port and starboard sides. These antennas, often referred to as Motion Reference Units (MRU), are very stable feed into the same computers that process the data. Therefore, the computer takes into account the readings from these antennas and combines this information with the corrections made for the tidal changes, sound velocity factors, and positioning of the ship. After cleaning the static from the data, a nautical chart can be produced. This method of charting the ocean floor is definitely more efficient than when researchers used lead lines—long ropes with lead that would be dropped down and then measured to determine the depth!

Personal Log

I woke up this morning after sleeping for about 12 hours—I think the seasickness medicine I took last night made me very sleepy. Luckily, however, all traces of seasickness are gone; I can even sit here at the computer and type without noticing the pitching of the ship very much at all. I think all of my muscles must be getting stronger as a result of reacting to the changing ground and all of the stairs I go up and down every day. I spent some time on the bridge this morning mostly asking questions about the tools used there and what various measurements mean. I find it very interesting that simply reading tiny numbers and using small switches and knobs will run this 231 foot ship. However, my experience aboard ships tells me that it is not even close to impossible. I know that even the slightest adjustment at the helm on a sailboat can change the course of the boat. I am reminded of sailing in the British Virgin Islands and the dispute over if it was more important to maintain the way point or try to make the boat go very fast. However, that is not an issue on this boat. We are supposed to reach the Shumagin Islands tonight, and tomorrow we will start the launches—I can’t wait!

Question for the Day

How many sets of data points must be filtered out before the data is considered clean? On what does this number depend? How does one determine if a data point is an outlier or and actual reading?