Tag: CTD

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Dana Tomlinson: Day 6, March 6, 2002

NOAA Teacher at Sea

Dana Tomlinson

Aboard NOAA Ship Ka’imimoana

March 1 – 27, 2002

Date: Wednesday, March 6, 2002

Latitude: 11°N
Longitude: 110°W
Seas: 2-5 ft.
Visibility: unrestricted
Weather: cloudy

Today was not as nice as it has been this week, but it still beats winter in Chicago (which I did for several years). And people from Chicago, please don’t write me that I hate Chicago – it’s one of my most favorite places. I have very fond memories of living there. Anyway, the seas have kicked up a bit, the ship is a’rocking and a’rolling and the weather is cloudy and humid. But life goes on here on the working laboratory that is the Ka’mimoana.

The significant event of the day was our first real CTD cast. I’ve written about these for the last few days, but today I want to really explain it because its scientific work is significant to the entire planet. Once again, CTD stands for Conductivity Temperature Depth. These are all things that are tested by this machine, and more. The machine itself is a steel frame that has 14 cylinders that hold from 4 to 5 liters of sea water that is captured at different depths in the ocean. There are numerous steps in the process of collecting the water – it’s not nearly as simple as it sounds.

First, the computers need to be set up. Then the machine itself has to have the bottles set properly to “fire” later. Then the winch operator and the CTD survey tech work together to lower the machine into the ocean down to 1000 meters. Once there, the survey tech “fires” off the first bottle by a computer key stroke – this snaps closed the top and bottom of the cylinder, thereby capturing the water at that depth. The winch hauls the machine up to 800 meters and it happens again. It happens again at 600m, 400m, 200m, 150m, 100m, 60m, 40m, 25m, 10m and surface. Then, the machine is hauled out by the winch operator (assisted by the survey tech in a life vest who is harnessed to the ship so she doesn’t fall overboard) and put back on deck. Before the machine is cast, when it is at depth and when it is at the surface, numerous statistics are notated such as SST (sea surface temperature) and SSS (sea surface salinity).

At this point, the survey tech shuts down the machines and the computers are done. Then the survey tech goes outside, fills up glass bottles with samples of the sea water from every depth that will be tested in a salinometer later. The machine is hosed down, tied down, and left for the next cast 6 hours later. The information collected from this machine taken over time (and NOAA has been doing these for years now) helps scientists to predict the El Niño and La Niña conditions which can wreak havoc world-wide.

Question of the Day: 

What is a thermoclime? (thanks to Ben Moore, NOAA scientist)

Answer of the Day: 

I guess I’m going to have to make these harder because all sorts of people got this one! Believe it or not, Vanessa P. of San Diego was the first one again to answer it! An anemometer is a device that measures wind speed and direction. Several of them are on board for deployment on the voyage.

Til tomorrow,
🙂 Dana

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Dana Tomlinson: Day 4, March 4, 2002

NOAA Teacher at Sea

Dana Tomlinson

Aboard NOAA Ship Ka’imimoana

March 1 – 27, 2002

Date: Monday, March 4, 2002

Latitude: 20 N
Longitude: 112 W
Seas: 4-7 ft.
Visibility: unrestricted
Weather: partly cloudy
Sea Surface Temp: 60-68 F
Winds: NE 13-18
Air Temp: 78/65 F

Happy Monday, all! And a very happy one it is out here. Last night, at sundown, we actually saw the elusive “green flash” at sunset. Personally, I think it’s a bit overrated! It was my first time seeing it and I expected a mini-St. Patrick’s Day explosion and got a little bitty green line on the horizon. Poof.

Anyway, today was another beautiful day in paradise. Since we are now south of the tip of Baja California, the weather is much balmier. I am thankful for the breeze the ship creates! We have 2 more days of transit before we encounter our first buoy and the scientists and crew are spending our days preparing for that.

Today, I received training in how to do a CTD line cast. CTD stands for Conductivity Temperature Depth. And those three things are what this machine measures – at depths of up to 1000 meters! These measurements are taken every 6 hours round the clock from the time we reach 12 degrees north latitude, which will be on Wednesday. There is a survey technician on board who does this, but to give her a break, some of us have volunteered to learn how to do it to relieve her once in a while. It involves computer operation as well as manually setting the instrumentation on the device (which is taller than my 5’8″ and much heavier). After setting the tubes to catch the water, it is deployed over the side by a winch and lowered to the desired depth. Then one of the 15 or so tubes on the device are tripped closed at the depths you desire on the way up. Once at the surface again, the water is removed from the machine into bottles and it’s on to the laboratory (on board) for testing. Fascinating. I can’t wait to be involved (see pictures in photo album 3).

Question of the Day: I’m going to make this a regular daily feature. The first person to get back to me will be mentioned in a future log. Today’s question: What is an anemometer? (There are several on board that will be deployed on the voyage.)

Answer of the Day: On Day 2, I asked what my #2 and #3 questions that people had asked me before I left San Diego were. Can’t tell you yet, because no one’s asked (or guessed)! Come on – any takers out there?

Til tomorrow, aloha! 🙂
Dana

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Jane Temoshok, October 13, 2001

NOAA Teacher at Sea
Jane Temoshok
Onboard NOAA Ship Ronald H. Brown
October 2 – 24, 2001

Mission: Eastern Pacific Investigation of Climate Processes
Geographical Area: Eastern Pacific
Date: October 13, 2001

Latitude: 11ºS
Longitude: 91ºW
Air Temp: 19.7 ºC
Sea Temp: 19.9 ºC
Sea Wave: 3-4 ft.
Swell Wave: 3 – 4 ft.
Visibility: 8 – 10 miles
Cloud cover: 3/8

Science Log

Energy from the Sun

The sun is the source of all energy on the Earth. The sun gives us this energy in the form of light and heat. Where does all that energy go? Why? How can it be measured? These are some of the questions many of the scientists on board are asking.

Toby Westberry and Olga Polyakov are scientists that have 2 instruments to help them understand how solar energy behaves in the ocean. The first is the SPMR which is a tool used to measure how much light penetrates the water. The more light = the more heat. You can see in the photo that it is a small black device attached to a long cord.

Temoshok 10-13-01 ucsbsbmrlaunch
Scientist Toby Westberry holds the SPMR, a tool used to measure how much light penetrates the water.

Toby and Olga lower the SPMR over the side and let it sink to 300 meters. Then they reel it back in just like a fishing pole. It tells them the “color” (wavelength) of the light at different depths. They do this over and over again in different locations in the ocean. Why? We know that the ocean water is not the same temperature in all places on the planet. Can you think of why this might be?

Well Toby and Olga know that there are tiny living organisms in the ocean that play a role in how warm or cool the temperature is. They are called phytoplankton. It seems that the more phytoplankton there is near the surface of the water, the more heat is trapped there.

Here’s an excellent explanation from Mrs. Richards of what’s happening that might help you to understand the process:

Imagine a nice clear swimming pool. The sun’s heat energy can penetrate all the way to the bottom of the pool because the water is so clear. Whatever heat energy hits the pool will be dispersed throughout the water somewhat evenly. Makes sense, right?

Now imagine that the pool has a layer of scum and algae at the top. Face it, you just haven’t done a very good job at cleaning the pool, and your allowance just isn’t big enough to make the job worthwhile. Now, the sun’s heat energy can’t pass all the way to the bottom of the pool because the scum is blocking the light. The very top of the pool water is going to capture almost all of the sun’s heat energy, and the bottom layers of water will be darker and colder. Imagine how the temperature of the water will be affected by the amount of scum in the water.

Knowing how much phytoplankton is hanging around would certainly help understand how the sun’s energy is being used. For this experiment they use a CTD. (Boy they sure use a lot of abbreviations for things!) This instrument is really big and needs a big machine called a winch to lift it in and out of the water.

Temoshok 10-13-01 ucsbctd
The CTD is lowered in and out of the water by a winch.

It has 12 tubes that fill up with water, each at a different depth.When the CTD is back on the ship, Toby and Olga fill labeled plastic bottles with the water.

Temoshok 10-13-01 ucsbctdcoll
Toby and Olga fill labeled bottles with the water collected at each depth.

Then their work begins. First they run all the water samples through a filter to figure out how much phytoplankton was in the sample.

Temoshok 10-13-01 ucsbolgalab
Scientist Olga Polyakov works with the water samples in the lab.

Remember each tube on the CTD took in water at a different depth. So each bottle will tell a different story. They use this information to create a data graph which is used with other information to tell how the sun is heating the ocean.

Travel Log

Sea birds! I don’t know how they do it or where they came from but all of a sudden 5 “boobies” showed up over the ship. What was amazing is that they hardly ever flap their wings, yet they fly as fast as the ship. The ship is moving forward at about 10 miles an hour and has big engines to push it. These birds just seem to glide along over us. Beautiful!

Temoshok 10-13-01 bird
A booby flies over NOAA Ship RONALD H. BROWN.

Question of the day: What is an updraft and what causes it?

Keep in touch,
Jane