Tag: anemometer

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Jennifer Fry, July 28, 2009

NOAA Teacher at Sea
Jennifer Fry
Onboard NOAA Ship Miller Freeman (tracker)
July 14 – 29, 2009 

Mission: 2009 United States/Canada Pacific Hake Acoustic Survey
Geographical area of cruise: North Pacific Ocean from Monterey, CA to British Columbia, CA.
Date: July 28, 2009

Map of the world showing longitude and latitude lines
Map of the world showing longitude and latitude lines

Weather Data from the Bridge 
Wind speed:  17 knots
Wind direction: 345° from the north
Visibility: 8 nautical miles /clear
Temperature: 16.8°C (dry bulb); 11.6°C (wet bulb)
Sea water temperature: 15.5°C
Wave height: 3-5 ft.
Air pressure: 1012.9 millibars
Weather note: Millibars is a metric unit used to measure the pressure of the air.

Science and Technology Log 

Weather Instruments and Predicting Weather 

Lt Oliver Brown, surrounded by navigational tools, and Fishery Scientist Steve DeBlois make observations on the bridge of the Miller Freeman.
Lt Oliver Brown, surrounded by navigational tools, and Fishery Scientist Steve DeBlois make observations on the bridge of the Miller Freeman.

Everything that happens out at sea is dependent upon the weather forecasts.  Throughout history man has used a variety of instruments to acquire accurate weather information.  The Miller Freeman is equipped with state of art weather reporting instruments. Every 3 hours weather data is sent to the National Weather Service to help predict the weather at sea.  Once again accuracy in reporting data is paramount.

Global Position: The Miller Freeman has several methods by which to determine longitude and latitude, which is our position in the ocean or on land.  There are 2 G.P.S. systems on the bridge, a magnetic compass, a gyro compass, and radar. These instruments help determine the ship’s position.

True north: The actual location of a point on the earth related to the north pole.

A Gyrocompass with cardinal headings including north, south, east, and west
A Gyrocompass with cardinal headings including north, south, east, and west

Magnetic north: Caused by the magnetic pull on the earth.  Magnetic north heading is different depending on where you are on the earth, for instance, Magnetic north in Oregon has a variation of 16.45°east from true north. Southern California has a variation of 13.3° east from true north.

Temperature: Measured by a thermometer, units used are Celsius. Dry bulb: Measures air temperature.  Wet bulb:  Uses a thermometer wrapped in a wet cloth. The dry and wet temperatures together give the dew point and help to determine humidity.

Wind Speed: Measured in knots using an anemometer, or estimated by using the Beaufort scale. The Beaufort scale uses observations of the sea surface, and the effects of wind on people or objects aboard ship to estimate the wind speed.

Wind Direction: Is measured by what direction in which the wind is coming.

Cloud Height/Type: Is measured visually.

Cloud Type: Is measured visually using a variety of names of clouds depending on their patterning and altitude.

Magnetic compass
Magnetic compass

Visibility: Is measured by estimating how much of the horizon can be seen.

Wave Direction: measured visually from the direction the wave comes.

Wave Height: The vertical distance between trough (bottom of the wave) and crest (top of the wave) and is usually measured in feet.

Swell Direction/ Height: Measured visually usually in feet.

Personal Log 

I have enjoyed my time on the bridge of the Miller Freeman immensely.  I have a better understanding of the weather instruments used onboard and am getting better at spotting whales and identifying birds. I want to thank the entire NOAA Corps Officers who have taught me so much about how navigation and weather work aboard the Miller Freeman.

Crewmember John Adams uses on-board weather instruments to record hourly weather readings that are then sent to National Weather Service.
Crewmember John Adams uses on-board weather instruments
to record hourly weather readings that are then sent to National
Weather Service.
An anemometer, which measures wind speed
An anemometer, which measures wind speed
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Diane Stanitski: Day 14, August 24, 2002

NOAA Teacher at Sea

Diane Stanitski

Aboard NOAA Ship Ka’imimoana

August 16-30, 2002

Day 14: Saturday, August 24, 2002

The FOO’s quote of the day: 

“I believe because it is impossible.” – Tertullian

Weather log:
Here are our observations at 0900 today:
Latitude: 4°40.8’N
Longitude: 139°58.7’W
Visibility: 12 nautical miles (nm)
Wind direction: 180° (constantly shifting)
Wind speed: 16 kts
Sea wave height: 3-4′
Swell wave height: 5-7′
Sea water temperature: 27.7°C
Sea level pressure: 1011.3 mb
Cloud cover: 7/8, Cumulus, Stratocumulus

Science Log:

Another buoy was repaired this morning because its anemometer wasn’t functioning. The anemometer is the highest object on the buoy and, therefore, is the most vulnerable. Because it’s not as protected and is a moving part, it can be easily damaged by people fishing the area, or by extreme weather. Dave was out on the buoy sitting in the horseshoe (a square opening on the starboard side of the buoy deck permitting you to work on the bottom of the buoy from the deck below) today testing and preparing it for deployment tomorrow. This will be our first buoy replacement, which means that when we retrieve the next buoy there will be oodles of work to do on the ship, including counting the thousands of barnacles that have attached themselves to the bottom of the brace. I can’t wait to smell the deck after they’re removed from the bottom – mm, mm!

On the agenda today is a full tour of the ship. John taped me both inside and outside explaining every part of the ship as we walked from deck to deck and bow to stern. I learned so much through that process. John first explained what we were looking at and then I provided my version as I tried to incorporate the technical terms. We also prepared some fun clips interviewing people about what they do on board.

Despite volunteering to do a CTD launch at 3°N tonight at 1930, the device wasn’t working. The 0130 reading at 2.5°N tomorrow morning was also cancelled because Larry and Jason need to switch out a major part that is malfunctioning. It will soon be time to rise and shine for a buoy retrieval (my first!) and deployment.

Personal Log:

I awoke this morning to sunshine streaming through our porthole. This is an unusual occurrence since it has been so cloudy. I walked outside and smelled FISH! The guys had pulled in the tow lines and they caught 4 gorgeous silvery mahi mahi fish, one over 20 lbs. When I went downstairs, they were filleting them in the kitchen for lunch and hopefully dinner! Wow! This is what I call fresh. They found tuna in one of the stomachs of the largest mahi mahi. I’ll have to make sure that I’m around when they pull in the next group.

Lobo, the Chief Engineer on board the ship, provided John, Takeshi (scientist from France), and me with a tour of the engine room this afternoon. The most fascinating thing to me is how fresh water is produced on the ship. We use approximately 3,000 gallons of fresh water per day, which means that we are each allotted about 100 gallons. This is plenty per person. The majority of the water is used for the CTD cast because fresh water has to be used to spray down the winch, wire, and cylinders after they are brought out of the water (see photo log for picture), and also for cooking and laundry. It is an extremely comfortable ship. The CO was saying today at lunch that the main halls are much wider than many ships and the staterooms are also more roomy. I was surprised at how decadent my room seems to be. Check out the photo log for a picture of my stateroom.

It is hard to believe how close we are to the equator. We continue moving southward along 140°W. I’m getting a little bit nervous about the fact that there are at least 6 people who have never crossed the equator before in a boat/ship. This means that we are called pollywogs. If time permits, there might be a ceremony at the crossing for all first timers, after which you become shellbacks. It’s not quite that easy, though. There is a certain amount of harassment (all in fun, of course) that must first take place to ensure that the wogs EARN the right to cross. Rumors are spreading that something might happen soon. I’ll keep you updated.

You would not have believed the bioluminescence in the water tonight! Kirby and Don spotted it first and suggested that I go up to the bow to peer over the edge at the bottom of the bow as it plows through the water. The phytoplankton become disturbed, which causes them to glow. There are often patches or clumps of these species that are visible making them look like a glow stick in the water. We may have also seen some jellyfish glowing, but only because they’ve eaten the bioluminescent phytoplankton. It’s so interesting. I love hanging my arms over the railing of the bow watching it carve out the water far below.

The sunset and moon rise were incredible tonight. The sun’s rays continued to light up the sky for about an hour after the sun actually set. The colors of light blue growing into bright pink were beautiful. We also had low cumulus clouds far beneath high cirrus clouds that turned pink. It was a spectacular scene (see photo log). I wish that I could have captured the moon rise over the ocean. It looked HUGE and was bright orange. There were thin clouds in the foreground that created an eerie, yet beautiful glow. The moon is almost full and illuminates the ocean surface like a huge flashlight. The Milky Way is in full view and the constellations are brilliant. We were looking for the Southern Cross tonight and think that we may have spotted it. Aaaahhhh!

I’ll write more tomorrow.
Diane