NOAA Teacher at Sea
Sena Norton
Onboard NOAA Ship Rainier
July 6 – 15, 2004
Mission: Hydrographic Survey
Geographical Area: Eastern Aleutian Islands, Alaska
Date: July 13, 2004
Location: At anchor, Popof Strait, Shumagin Is. AK
Latitude: 55 deg 17.9’ N
Longitude: 160 deg 32.13’W
Visibility: 1nm
Direction: 116 deg
Wind Speed: 10 kts
Sea wave height: n/a
Swell wave height: 0-1 ft
Seawater temperature: 10.1 deg C
Sea level pressure: 1011.0 mb
Cloud Cover: 8/8 Fog
Weather: Foggy with drizzle and areas of rain 12.1 deg C (air temp)
Plan of the Day:
Four launches for shoreline verification and continuation of hydro in deeper water.
Science and Technology Log
I learned the process and background concerning shoreline verification. This process ties in nicely with my new understanding of the process of Laser Airborne Bathymetry and how the two connect together. Shoreline verification is a process where a launch surveys to the 4-meter line and in the process correctly locates any targets found close to shore. The launch actually touches the target, at times from multiple sides so that a true GPS tag can be attached to the feature. This process helps the survey crew make better sense of wide swath readings and discern between sonar “fluff” and true features. Sometimes kelp or other objects block the sonar from capturing an accurate image and in the case of larger objects they are required to be “eye ball” verified for all survey areas. Shoreline is also used to double check location of known targets for drift or geologic movement. In the case of these Alaskan waters, the bottom changes yearly and the same can be said for the shoreline. Rocks move, and sand drifts cause sediment build-ups in different areas and underwater features might not have been placed accurately on the chart in the first place. All these factors add in to the need for physical shoreline verification of the survey swaths.
The jet boat launches are able to go almost all the way into shore but are not used until a prop motor launch has already done a through evaluation of the grid. According to the coxswains, shoreline is one of the more nerve-racking operations that they conduct. They are in shallow water trying to find hazards to navigation and they are still asked to safely navigate themselves. At times they are going into pockets almost blind because of the initial survey information being a tad sketchy. After of day of shoreline the coxswain is mentally and physically worn out.
Personal Log
Last night was a fun night on board, a group of crew and corps officers played some board games and let off some steam. This really is a fun crew to be around they are ready to have a good time and I believe they genuinely enjoy each other’s company. (Even if at times I know they drive each other crazy!) I am feeling more a part of the ship now as ever before, everyone is a friendly face and people are interested in what I am doing and what I do on dry land. They are very supportive of teachers and education and that is a boost to my morale because I feel supported in what I am doing here.
I have also enjoyed the time made available by being on board to work with the other TAS and collaborate with lesson ideas and simply “talk” to each other. Many times the one thing that teachers starve for is a chance to really get down and work with their colleagues. We are already planning on linking our classrooms, like Sister Classes for projects, pen pal and even to track the weather on opposite sides of the U.S. An added benefit is that she also just finished her first year of teaching and teaches at the same middle school level and I do. We have our careers in common and seem to have similar ideas on the direction of science education and its benefit to our students. We have completely different experiences as an educator because I teach in public school and she teaches in a small private school, but hearing the experience of the other has put a perspective not only on education but also on my professional/personal goals for the future of my career.
Question of the Day:
What is a “gyro” and why is it used on a ship?
A “gyro” or gyroscopic compass is the ships compass that is always pointed at the North/South axis no matter what the ship is doing in the water. It can be compared to a child’s top in the way that it works. It is important for a ships compass to be oriented in the N/S axis to accurately navigate and find the exact lat/long point. A compass will always point toward magnetic North which is about 1,600 km south of the North Pole (where all the meridians of longitude converge).