Aboard NOAA Ship Oscar Dyson
July 4 — 22, 2011
Mission: Walleye Pollock Survey
Date: July 9, 2011
Weather Data from the Bridge
True wind direction: 59.9°, True wind speed: 11.44 knots
Sea Temperature: 9°C
Air Temperature: 8.9°C
Air pressure: 1009.74 mb
Foggy with 1 mile visibility
Ship heading: 88°, ship speed: 11 knots
Science and Technology Log
The Shumagin Islands are a group of about 20 islands in the Gulf of Alaska, southwest of Kodiak Island. They were named for Nikita Shumagin, a sailor on Vitus Bering’s Arctic voyage in 1741. They are volcanic in origin, composed mostly of basalt.
Several islands even exhibit hexagonal basaltic columns. There are about 1000 people who reside in the islands, mostly in the town of Sand Point, on Popof Island. According to the United States Coast Pilot (a book published by NOAA with extensive descriptions about coastlines for ship navigation), the islands extend out 60 miles from the Alaskan Peninsula. They are bold and mountainous.
The shores are broken in many places by inlets that afford good anchorages. The shores are rockbound close to. Fishing stations and camps are scattered throughout the group, and good fishing banks are off the islands. Fox and cattle raising are carried on to some extent.
Sea water quality is very important to the scientists on the Oscar Dyson. So important, that it is monitored 24 hours a day. This is called the Underway System. The sea water comes through an intake valve on the keel of the bow, and is pumped up and aft to the chem lab. There, it goes through 4 instruments: the fluorometer, the dissolved Oxygen unit, the Thermosalinograph (TSG), and the ISUS (nitrate concentration).
The fluorometer measures the amount of chlorophyll and turbidity in the sea water once every second. A light is passed through the water, and a sensor measures how much fluorescence (reflected light) the water has. The amount of chlorophyll is then calculated. The measurement was 6.97 µg/L when I observed the instrument. The amount of phytoplankton in the water can be interpreted from the amount of chlorophyll. Another sensor measures how much light passes through the water, which gives an indication of turbidity. Twice a day, a sample of water is filtered, and the chlorophyll is removed. The filter with the chlorophyll is preserved and sent to one of the NOAA labs on land for examination.
The next instrument that the water passes through will measure the amount of dissolved oxygen every 20 seconds. Oxygen is important, because aquatic organisms take in oxygen for cellular respiration. From plankton to white sharks, the method of underwater “breathing” varies, but the result is the same – oxygen into the body. The oxygen in the water is produced by aquatic plants and phytoplankton as they do photosynthesis, and the amount directly affects how much aquatic life can be supported.
The TSG will measure temperature, and conductivity (how much electricity passes through) every second, and from these 2 measurements, salinity (how much salt is in the water) can be calculated. The day that I observed the TSG temperature was 8.0° C, and the salinity was 31.85 psu (practical salinity units). Average sea water salinity is 35. The intense study of melting sea ice and glaciers involves sea water temperature measurements all over the world. A global data set can be accumulated and examined in order to understand changing temperature patterns.
The last instrument measures nitrate concentration in the sea water every couple of minutes. It is called ISUS, which stands for In Situ Ultraviolet Spectrophotometer. Nitrate comes from organic waste material, and tends to be low at the surface, since the wastes normally sink to the bottom. The normal value is .05 mg/L, at the surface, at 8°C. Values within the range of 0.00 to 25 mg/L are acceptable, although anything above 5 is reason for concern.
All of the data from these instruments is fed into a ship’s computer, and displayed as a graph on a monitor. The Survey Technician monitors the data, and the instruments, to make sure everything is working properly.
New Species Seen today:
Whale (unknown, but probably grey or humpback)
Living on a ship is quite different from living at home. For one thing, every item on the ship is bolted, strapped, taped, or hooked to the bulkhead (wall), or deck (floor). Most hatches (doors) have a hook behind them to keep them open(this reminds me of when I put hooks behind my doors at home to keep little children from slamming them and crushing fingers). Some hatches (around ladderways (stairwells)) are magnetically controlled, and stay open most of the time. They close automatically when there is a fire or abandon ship situation or drill. Every drawer and cabinet door clicks shut and requires moving a latch or lever to open it. For some cabinet doors that you want to stay open while you are working in the cabinet, there is a hook from the bulkhead to keep it open.
On every desk is a cup holder, wider on the bottom than the top, designed to hold a regular glass or a cup of coffee. If one of those is not handy, a roll of duct tape works well for a regular glass. All shelves and counters have a lip on the front, and book shelves have an extra bar to hold the books in. Trash cans and boxes are lashed to the bulkhead with an adjustable strap, and even the new copier machine has a special brace that is bolted to the deck to hold it in one place (I heard that the old copier fell over one time when there was a particularly huge wave). There are lots of great pictures on the bulkheads of the Oscar Dyson, and each one is fastened to the bulkhead with at least 4 screws, or velcro. There are hand rails everywhere – on the bulkhead in the passageway (hallway) (reminds me of Mom’s nursing home), and on the consoles of the bridge.
Desk chairs can be secured by a bungee cord, and the chairs in the mess (dining room) can be hooked to the deck.
Another thing that is different from home is the fact that the Oscar Dyson operates 24-7 (well, in my home, there could easily be someone awake any hour of the night, but the only thing they might operate is the TV). The lights in the passageways and mess are always on. The acoustics and water quality equipment are always collecting data. Different people work different shifts, so during any one hour, there is usually someone asleep. Most staterooms have 2 people, and they will probably be on opposite shifts. One might work 4 am to 4 pm, and the other would work 4 pm to 4 am. That way, only one person is in the room at a time (there is not really room for more than one). There is always someone on the bridge – at least the Officer of the Deck (OOD) – to monitor and steer the ship. During the day, there is usually a look out as well.
His job is to, well, look out – look for floating items in the water, whales, rocks, and other ships (called contacts or targets). This helps the OOD, because he or she can’t always keep their eyes on the horizon.
I have thoroughly enjoyed living on the Oscar Dyson (we have had calm seas so far), and talking with the NOAA staff and crew. They are ordinary people, who have chosen an extraordinary life – aboard a ship. It has challenges, but also great rewards – seeing the land from a different perspective, being up close to sea life, and forging close relationships with shipmates, as well as participating in the science that helps us understand the world’s oceans.