NOAA Teacher at Sea
Elli Simonen (she/her)
Aboard NOAA Ship Fairweather
July 10, 2023 – July 28, 2023
Mission: Hydrographic Survey of the Pribilof Islands
Geographic Area of Cruise: Pribilof Islands, Alaska
Date: July 24, 2023
Weather Data
Location: 56°36.8259’N,169°32.2224’W
Outside temperature: 11°C
Water temperature: 10°C
True Winds: 16kn, 185.4°
Skies: Foggy with Drizzy Rain
Visibility: 5nmSea
Wave: 1-2 ft
Swell Wave: 1 ft
Science and Technology Log
We are currently at anchor off the north shore of Saint George Island and the survey launches are going out daily to survey a portion of the surrounding waters. I have been on the survey launches twice, each time surveying a different area.
Survey Launch July 22, 2023
The Pribilof Islands are the breeding grounds for more than two thirds of the world’s fur seal population and their numbers peak in July. Our surveying operations do their best not to disturb the Fur Seals. I was on a launch that was assigned the harbor. However, upon entering, we saw a colony of Fur Seals and had to turn back around. We then went onto survey another area in open water. Later that morning, the winds increased and all survey launches returned to the ship out of caution for the weather.
Entering the harbor at Saint George
Fur Seals in the Saint George harbor
Survey Launch July 23, 2023
We went out to survey an area closer to shore and were out all day – a good weather day. We surveyed using set lines; this is where survey lines are parallel and evenly spaced apart. During post survey data processing, these lines of coverage will be used to update soundings on the chart. Set lines are used in areas of shallow water where there is not much bathymetric data, such as the Pribilof Islands. This process allows the survey team to complete a larger survey area in less time.
Our surveying boundary close to shore is defined by the navigational area limit line (NALL), which is the distance from shore that vessels can reasonably navigate. The other boundaries are mapped out by the survey team ensuring coverage of the entire area. During surveying in addition to depth data, any information about features that can impact navigation need to be noted. This can include an outcrop of rocks, shipwrecks or a kelp forest. We did see a kelp forest close to the shoreline during this survey, and indicated that in our data. Kelp forests can increase or decrease in size depending on the year and water temperature, but generally stay in the same place.
The swath is the width of the survey lines. During surveying the swath gets larger as the depth increases. In this survey, as you move away from shore the depth becomes deeper, so the width of the swath increases as well. This is due to the fact that the MBES angle is fixed and the depth is related to the swath by the tangent function.
Screen showing the set line spacing and data taken near the shore.
Close to the shoreline of Saint George. The color change of the water indicates a kelp forest. Thousands of sea birds are on the cliffs.
How the width of the swath can be calculated.
TAS Elli Simonen on a survey launch close to shore of Saint George, one of the Pribilof Islands
At the Helm of the Survey Launches
Coxswains are responsible for steering and navigating the survey launches. They use a variety of instruments and sensors to maintain safety and guide the survey launches over the planned survey lines. The heading is the direction the bow of the ship is pointing, expressed as a degree measurement from 0° to 360°. We were mainly surveying lines that were running north-south and the heading measurement was 0° when we went north and 180° south.
Heading indicator showing the direction of the survey launch and allows for autopilot.
Magnetic Compass showing heading on the survey launches.
Screen for coxswains on survey launches showing depth, the water column and survey lines.
TAS Elli Simonen attempting to steer the Survey Launch with NOAA Corps member ENS Ashley Howell. It is much harder than it looks!
Personal Log
Day to Day
Most of my days have been spent on the ship or lately, on survey launches. If I’m on the ship, I usually spend most of the day in the survey room with the survey technicians. Breakfast is served from 7-8 am, lunch is from 11-12 pm and dinner is 5-6 pm. Sometimes a movie is shown in the lounge in the evenings, but the other day we streamed the Women’s World Cup to see the USA win their opening game!
Some of the common areas of the ship
The survey room where all the survey technicians have their work stations.
The galley with lunch available
The mess, where we all eat meals.
Washers, dryers and soap are provided for everyone’s use.
Did You Know?
- Fur Seals leave the Pribilof Islands in November and females and immature males swim to the south, some as far as the California-Mexico border. They return to the Pribilof Islands in June. (https://www.adfg.alaska.gov/index.cfm?adfg=northernfurseal.printerfriendly)
- The Pribilof Islands are also home to millions of sea birds. Birdwatchers can see red-faced cormorants, red-legged kittiwakes, northern fulmars, thick-billed murres, and puffins. These species nest in the island’s cliffs and tundra. (https://www.adfg.alaska.gov/index.cfm?adfg=viewinglocations.pribilofislands)
