NOAA Teacher at Sea
Dana Clark
Onboard NOAA Ship Fairweather
June 23 – July 3, 2014
Mission: Hydrographic Survey
Geographical area of cruise: South Coast of Kodiak Island
Date: June 24, 2014
Weather Data: Latitude – 56° 45.35′ N, Longitude – 154° 10.0 W, Sky Condition – 7/8 clouds, Present Weather – clear, Visibility – 10 nautical miles, Wind – calm, Temperature – 13.8 C°
Science and Technology Log
Yesterday was my first day underway on NOAA Ship Fairweather. Before I could participate in all the cool science I had to complete all the safety training. I am now ready to survive any situation on ship since I have successfully completed a fire drill, abandon ship drill, donned my survival suit, and learned how to deploy a life raft. See how I look in my survival suit!
Before I tell you about all the great science we’re doing, I want to address the earthquake and tsunami that hit Alaska and was widely reported yesterday. There was an 8.0 earthquake near Alaska’s Aleutian Islands, southeast of Little Sitkin Island that triggered a tsunami warning; however, only small waves hit the coastal communities. This was west of Kodiak Island and we were not affected by it. In speaking with the experts on the ship, they explained that we were safer on a ship than shore and a tsunami would roll under the ship. I wondered if it was normal to have these alerts since earthquakes happen everyday in Alaska, and veteran scientists on the Fairweather said that they had never had an earthquake with a tsunami warning before. What an exciting event on my first day!
Today I was ready to go out on a launch. This is a 28 foot boat that uses a suite of hydrographic hardware and software, such as a multi-beam sonar to map assigned sections of the seafloor. I set out with Tim, who is a coxswain which means he is a small boat operator for commissioned vessels, Clint, who is a hydrographic senior survey technician and Joy, who is a hydrographic survey technician. And me, a Teacher at Sea! Our mission was to do cross lines of sonar mapping to check that there are no erroneous offsets between days of data. We also would pick up holidays, which are gaps in the data, and go over them with sonar. We are mapping South Kodiak Island this week and more specifically for today, we are mapping around Aiaktalik Island.
We begin by using a CTD which stands for Conductivity, Temperature, and Depth. This instrument measures conductivity, temperature, and pressure which can be used to derive the speed of sound throughout the water column. It will help to correct for refraction of the sound wave emitted from the sonar as it passes through varying layers of the water column. The multi-beam sonar sends out 512 beams at a rate of 4.5 pings per second. The number of beams is independent of water depth but the swath width is dependent on water depth. We then measure how long it takes for them to get to the bottom and back, which is called two-way travel time. The multi-beam sonar provides us with bathymetric data, which is simply a large density of depths used to generate a surface representing the seafloor. Then we record the measurements. In the picture below you will see Joy recording the data from the sonar.
Scientist of the Day
Today I would like you to meet Joy Nalley, a Hydrographic Survey Technician for NOAA who is currently aboard the Fairweather. As a girl, she was always interested in science. She said she even spent most of her childhood playing in a large magnolia tree. Her love of nature continued as a teenager as she spent summers on the lake. She went to the University of Alabama where she earned a BS in Environmental Science, a Minor in Geology, and a Specialization in Hydrology. During school she earned experience in her field by working in a research position and an internship. After college she did another internship in order to gain experience. Her research participation along with the internships allowed her to get an interview and subsequent job with USGS which is the United States Geological Survey. There she was a hydrologic technician for two years. This meant that she studied the water and took data from the actual water. This job then lead to her current position with NOAA where she is a hydrographic survey technician. Now she takes data from the actual seafloor in order to map it. This is a relatively new field of science. There is a lot of seafloor to map since less than 5% has been mapped this way, hence making it a desirable career. Joy says that to go into her field you should be adventurous, want to work with cool people on a team, and have an interest in marine science; then this is the career for you!
Personal Log
I had a good first two days and survived rolling seas last night without feeling seasick. I think I have my sea legs on now! Since several of you are wondering, the food is very good. The cooks take good care of us here. I am also getting a lot of exercise going up and down the six decks on the ship and doing the survey work on the launch. I saw many animals while out on the launch today including a harbor seal, sea gulls, puffins, multiple giant jelly fish, and a bright purple jelly fish! What a great time I’m having doing science with such a wonderful group of highly trained, experienced, and interesting crew aboard the Fairweather!
Question: What is this? Plant or animal? Answer in the poll below.
This was great! I learned things I would have never known. Thanks! I’m glad you already have your “sea legs.” I look forward to future posts!
Dana – Thanks for the post. Your trip is getting nice local coverage here, including a piece in today’s DMN complete with photo!
Larry
Good to hear, thanks!
Love it