Debbie Stringham, July 12, 2005

NOAA Teacher at Sea
Debbie Stringham
Onboard NOAA Ship Fairweather
July 5 – 15, 2005

Mission: Hydrographic Survey
Geographical Area: North Pacific, Alaska
Date: July 12, 2005

Stringham on shore, Eagle Harbor, Shumagin
Stringham on shore, Eagle Harbor, Shumagin

Weather Data 

Location: Eagle Harbour, Shumagin Islands, AK
Latitude: 55 06.8’ N
Longitude: 160 06.9’ W
Visibility: 10 nm.
True Wind Speed: 16 kts.
True Wind Direction: 340
Sea Wave Height: 1 ft.
Swell Wave Height: none
Swell Wave Direction: none
Sea Water Temperature: 12.0 C
Sea Level Pressure: 1011.5 mb
Sky Description: Partly Cloudy
Dry Bulb Temperature: 15.5 C
Wet Bulb Temperature: 12.5 C

Science and Technology Log 

View from vessel during bottom sampling operations.
View from vessel during bottom sampling operations.

Today, is a quiet day aboard the FAIRWEATHER. There are no vessel launches to join, but it is a good opportunity for me to work on lesson plan ideas. I’ve been most interested in the bottom sampling operations and why it is important to understand the nature of the sea floor for anchorage. I found a very helpful seaman text that should provide good direction for a lesson plan.

Earlier in the leg, a crew member and survey tech exchanged with a member of a contractor for NOAA that acquisitions hydrographic data using airplanes. The airplanes essentially have two beams, one that hits the top of the water and one that penetrates to the sea floor. The data is then compared and the difference between them equals the water depth. The survey tech said that there are some benefits and limitations to the use of airplanes.

Benefits are that it can collect data much more quickly than our ship. Our ship travels at ten knots, but the airplane can fly over a hundred knots and cover many more miles. The airplane can also collect data in shallow water and pinpoint water depth over shallow rocks whereas the ship cannot. Also, Surveyors do not have to stay at sea for weeks at a time and can go home to dry land at the end of the day.

On the other hand, limitations of the airplane include lower resolution because the plane is flying so fast. Choppy seas or kelp forests impede data collection, as is true for data acquisition from the ship as well, and the planes cannot collect data from deep waters.

Question of the Day 

What type of sea floor is best for anchoring one’s ship?

Answer from Previous Day 

Understanding atmospheric sciences is important in navigating ships because the weather affects the ship’s course and ability to conduct business or research every day. Understanding such basic concepts as weather fronts, air mass characteristics, large scale wind systems (ie.  Polar Easterlies), and weather phenomenon (ie. hurricanes) can be life saving when out at sea.

Shumagin Islands, AK. Islands, AK.
Shumagin Islands, AK. Islands, AK.

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