Tag: gulf of alaska

Posted on

Dan Steelquist, July 16, 2009

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

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

Weather Data from the Bridge 

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

Science and Technology Log 

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

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

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

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

Personal Log 

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

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

Posted on

Dan Steelquist, July 12, 2009

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

Mission: Hydrographic Survey
Geographical Area: Pavlov Islands, Gulf of Alaska
Date: July 12, 2009

Weather Data from the Bridge 
Latitude: 55° 13.541′ N
Longitude: 161°22.332′ W
Visibility: 6 Nautical Miles
Wind Direction: Variable
Wind Speed: Light
Sea Wave Height: 0-1ft.
Swell Waves: 1-2ft.
Water Temperature: 8.3° C
Dry Bulb: 10.6° C
Wet Bulb: 10.6° C
Sea Level Pressure: 1020.3 mb

Science and Technology Log 

Here I am finding my name on the POD—Plan of the Day.
Here I am finding my name on the POD—Plan of the Day.

In order for a ship like Rainier to complete her work, many different people and departments must work in a coordinated fashion to accomplish the goals of the mission. Unlike many types of science field study, the work of a hydrographic survey ship requires that she goes out as a self contained work platform. All of the needs of crew and equipment must be able to be met with whatever is on board the ship.

A very important part of the coordination of Rainier’s mission is called the Plan of the Day, or POD. The POD is developed by the Field Operations Officer, or FOO, the day before it is to be implemented. The POD is posted throughout the ship, in 16 different locations. Every person on the ship needs to be aware of what is happening and what their role in the day’s plan is. General information included in the POD would be the date, the ship’s position, times of sunrise and sunset, times of high and low tides, weather and sea state  forecast, and which US Coast Guard global positioning system (GPS) beacons are to be used for more accurate position location. Specific information on the POD includes whether or not Rainier is at anchor or moving, which survey launches are going out for the day and where they will be working, who is on each of the survey launches and what their specific role is to be, what sort of survey work is being done on Rainier and who is in involved with that, who is responsible to process data collected during the day, and who is on watch on the bridge and when they are scheduled to be there. In order for any important scientific work to be completed, everyone involved in the process must work together. The POD is the tool used on board Rainier to make that happen.

Personal Log 

This is my eighth day aboard Rainier and I continue to learn new things. I have been out in the survey launches a number of times and I have been able to participate in many of the tasks involved in the ship’s mission. The technology involved is complex and the steps involved in the work of charting are many, but everyone on board works together very well. I feel very fortunate to be able to get a glimpse of the work these people do. Now that I know my way around the ship, what each department does, and the way that work all fits together, I am understanding how underwater feature locations and water depth information get from the real world into the hands of scientists and mariners.

Something to Think About 
If you made a POD for your day what sorts of information might you include? Would a POD make working with others more productive?

Posted on

Dan Steelquist, July 7, 2009

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

Mission: Hydrographic Survey
Geographical Area: Pavlov Islands, Gulf of Alaska
Date: July 7, 2009

Weather Data from the Bridge 
Latitude: 56° 20.76′ N
Longitude: 157°09.52′ W
Visibility: 10+ Nautical Miles
Wind Direction: 220° true
Wind Speed: 14 knots
Sea Wave Height: 1-2ft.
Swell Waves: 3-5ft.
Water Temperature: 9.4° C
Dry Bulb: 11.7° C
Wet Bulb: 11.1° C
Sea Level Pressure: 1021.0 mb

Science and Technology Log 

The Rainier is a self-contained workstation that has many different types of jobs that need to be done. As I have arrived and settled in, I have tried to learn what jobs people do on board and how their work contributes to mission of the ship.

The workers on the ship are divided into six different departments.

  • The officers oversee the total operation of the ship. They plan the ship’s course and control the ship from the bridge while it is underway.  The officers are also involved in the survey operations
  • The Survey Department gathers and processes hydrographic survey data.
  • The Electronics Department maintains electronic equipment and electrical systems on board the ship.
  • The Stewards keep the crew fed
  • The Deck Department handles all the work on the deck including launching and retrieving the small boats. They also handle the lines when the ship is docking and they operate machinery to raise and lower the anchor
  • The Engineering Department maintains and operates the ship’s engines and generators.

There are many different career opportunities on a ship like the Rainier. Some of the jobs are similar to land based work, yet with a nautical twist. Most of the jobs require some specialized training. All of the jobs appear to be both challenging and rewarding.

Personal Log 

That’s where I’ll be living for the next 3 weeks: NOAA Ship Rainier
That’s where I’ll be living for the next 3 weeks: NOAA Ship Rainier

Wow, what an experience so far. Ship life is so much different than life on land. There is so much to learn and know. There are necessary procedures for every aspect of this world and the crew of the Rainier has been very helpful in making me feel welcome.  Once we left the dock in Seward, the importance of clear procedures became obvious. Moving this much equipment around an ocean with people living and working on board is no small feat. Everyone has very specific jobs to do and time and places they are assigned to work. I have spent much of my time finding my way around the ship and getting to know what types of jobs these people have. The trip from Seward to our work area takes about forty hours. Once there, we will begin the survey work. Our ship has been assigned the task of surveying the seafloor in some areas that have never before been charted. Once we get that work underway, I’ll be able to peer further into the world of a hydrographic survey ship. The adventure goes on…

Something to Think About 
How might the types of work on a ship like the Rainier be similar to and/or different from a closely related job on land?

Posted on

JoAnne Kronberg, July 16, 2005

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

Mission: Hydrographic Survey
Geographical Area: North Pacific, Gulf of Alaska
Date: July 16, 2005

Weather Data
Winds:  Southwest at 20 knots
Waves: 7 feet
By tonight, the winds should become totally west at 20 knots the wave height should drop to 6 feet.

Science and Technology Log

We have finally gotten across the Gulf of Alaska and tomorrow will begin some real work again. We entered the Shelikoff Strait and will proceed toward the vicinity of the Semidi Islands.  Our goal is to reach Mitrofania Island by Tuesday morning.

The Plotting Room on the NOAA ship RAINIER

Today I spent my day in the Plotting Room with one of the navigators named Brent.  He showed me how they use the information we accumulated on July 13 while on Launch #5 in Barrows Bay. On that day we were surveying two different sections by the multi-line sensors. As the beams were sent out, they recorded whatever was in the water and on the bottom to the computer on the launch.  This information was also transmitted to the proper program on a computer on the RAINIER.  Now the technologists, interns, scientists and engineers analyze the information as it appears on the computer screens.  Daily, already programmed into the computer, are the variations that will change such as the tides, currents and temperatures. In this way, the information is as accurate as possible. By observing the screens, the scientists, plotters and hydrographers can chart the depths, obstacles,(such as crab pots or rocks), temperatures and currents.  All of this information is plotted on paper charts for all navigators and ship captains, whether their ships are owned by the United States, commercial enterprises or private sailors.

The men and women who do this work have varied backgrounds and education.  Some are mechanical engineers, geography scientists, geologist, interns and college students who are learning hydrography.

That’s it from the RAINIER JoAnne Kronberg Teacher-at-Sea