Spencer Cody
Onboard the NOAA Ship Fairweather
May 29 – June 18, 2016
Mission: Hydrographic Survey
Geographical Area of the Cruise: along the coast of Alaska
Date: June 18, 2016
Weather Data from the Bridge:
Observational Data:
Latitude: 55˚ 20.643′ N
Longitude: 131˚ 37.505′ W
Air Temp: 20˚C (68˚F)
Water Temp: 13˚C (55˚F)
Ocean Depth: 30 m (100 ft.)
Relative Humidity: 65%
Wind Speed: 9 kts (11 mph)
Barometer: 1,022 hPa (1,022 mbar)
Science and Technology Log:.
While horizontal control base stations are used to improve the accuracy of the positions of all points on a surface by providing a fixed known location to compare to GPS coordinates, constantly changing tides present another challenge in of its own. With tides in the survey area ranging 3 to 6 meters (10 to 20 ft.), depths can vary widely for various shallow-water hazards depending on the strength of the tide. Consequently, accurate tide data must be recorded during the survey and in close proximity of the survey site since tides vary widely depending on topography, weather systems, and other factors. This is where tide stations come into play and are necessary to accurately gauge the vertical level of water throughout the survey area.
Before a survey is started in an area, a tide station can be set up within the survey area to measure local tides. The tide stations use solar cells to generate electricity to power a small compressor on land that sends air through a hose that is attached to the ocean bottom in a near-shore environment. The tide gauge can measure how much pressure is needed to generate a bubble out the end of the hose, the greater the pressure, the deeper the water. These pressure gradients correlate to a certain depth of water while the depth of the water is tied to a nearby benchmark of surveyed elevation. This information is then transmitted out to tide reporting sites online. For additional data on tide patterns, the information on tide levels can be downloaded from the gauge in refining survey data. In order to ensure that a tide gauge is working correctly, manual tide observations are periodically made at the same location. Additionally, the benchmarks near the tide gauge go through a process called “leveling.” This is survey work that compares all of the secondary benchmarks in the area to the primary benchmark. If none of the benchmarks have moved relative to each other, it is safer to assume that the benchmarks still represent the elevation that they were originally surveyed. Once the survey in the area is completed, the tidal gauge is packed up to be used at another location. Since the portion of the tidal gauge that releases the pressurized bubble is under the entire tidal water column, a dive team is required to remove the remaining equipment. The entire tidal gauge site is returned to how it looked before the station was set up. Only the survey benchmarks remain for future use.
Personal Log:
Dear Mr. Cody,
On our cruise ship there are officers that wear uniforms who run the ship. They also look out for the safety of everyone onboard. They are very nice and know a lot about how to keep the ship running and get the cruise ship to each stop on our vacation. They work with each department on the ship to make sure everything runs properly and people stay safe. It has been a great trip to Alaska, and now we are at our last stop. Goodbye Alaska! (Dillion is one of my science students who went on an Alaska cruise with his family in May and has been corresponding with me about his experiences as I blog about my experiences on the Fairweather.)
Dear Dillion,
The Fairweather also has officers, the NOAA Corps, to help run the ship and carry out NOAA’s mission by utilizing NOAA’s fleet of ships and aircraft and by staffing key land-based positions throughout the organization. The NOAA Corps ensures that trained personnel are always available to carry out NOAA’s missions using cutting-edge science and technology. This gives NOAA the flexibility it needs to complete many types of varied research since officers are trained to fulfill many types of missions. This gives NOAA the ability to respond quickly to scientific and technological needs and helps retain a continuity of operations and protocol throughout the vast fleet and area of operations. In order to be considered for acceptance into the NOAA Corp, applicants must have at least a four year degree in a field of study relating to NOAA’s scientific and technological interests. Once accepted into the program, they go through five months of training at the United States Coast Guard Academy where they develop an understanding of NOAA’s mission, maritime and nautical skills, and general ship and boat operation skills. After successful completion of the training, NOAA officers are placed on a ship in the fleet for three years of sea duty to begin their new career.
On the Fairweather NOAA Corp officers help run and manage the ship and launch boats. They navigate the ship and stand watch on the bridge. They work with the other departments to ensure that the mission is accomplished and everyone remains safe during the mission. On a hydrographic survey ship such as the Fairweather, Corps officers commonly have the position of sheet manager for hydrographic survey regions as collateral duties allowing them the opportunity to plan the logistics of hydrographic survey areas and learn how to use software associated with hydrographic data collection and analysis. Additionally, officers will be assigned to other scientific missions as they arise since the Fairweather will participate in a variety of scientific projects throughout the year.
A hydrographic ship such as the Fairweather requires many departments to work together including the NOAA Corps officers to accomplish the mission. There is the deck department and engineering department and the steward department as I have discussed their role in previous posts. However, there are also electronic technicians that assist the survey in all of its technological aspects including the ship’s servers, electronics, radar, and communication systems. Since technology plays a critical role in the collection and analysis of data, a hydrographic ship depends on these systems to carry out its scientific research.
The survey department does the bulk of the collection and analysis of hydrographic data. Depending on experience and education background, someone in survey may start out as a junior survey technician or assistant survey technician and advance up to a survey technician, senior survey technician, and possibly a chief survey technician. With each step more years of experience is required because a greater amount of responsibility comes with each position concerning that survey. Survey technicians generally need to have a background in the physical sciences or in computer science. Technology and physical science go hand-in-hand in hydrographic survey work by applying and analyzing scientific data through the lens of advanced technology and software. One needs to be capable in both areas in order to be proficient in the survey department.
It really comes down to people working together as a team to get something done. In the case of the Fairweather, all of this talent and dedication has been brought together in a team of NOAA Corps, engineers, deck, survey, technicians, and stewards to carry out a remarkable array of scientific work safely and efficiently. This team is always ready for that next big mission because they work together and help each other. Yes, Dillion, my time here on the Fairweather is also drawing to a close. I have enjoyed the three weeks onboard and have learned a lot from a very friendly and informative and driven crew. I thank all of those who were willing to show me what their job in NOAA is like and the underlying concepts that are important to their careers. I learned a great deal concerning NOAA careers and the science that is carried out onboard a NOAA hydrographic ship. Thank you!
Did You Know?
The NOAA Commissioned Officer Corps is one of seven uniformed services of the United States consisting of more than 300 officers that operate NOAA’s fleet of 16 ships and 9 aircraft.
Can You Guess What This Is?
A. a ship B. a hydrographic survey C. a NOAA vessel D. a final farewell to an amazing ship and crew
You should already know the answer if you have been following this blog!
(The answer to the question in the last post was C. an azimuth circle. The Fairweather has an azimuth circle onboard. While it is not typically used for navigation, it is yet another technology that remains as a holdover from earlier seafaring times and as a potential navigation tool available when all modern equipment has failed. The azimuth circle can be used to measure the position of a celestial body for navigation purposes or to get a bearing on an object visible from the ship.)
