CTD sensor – Page 3 – NOAA Teacher at Sea Blog

August 14, 2009April 6, 2021

Christine Hedge, August 14, 2009

NOAA Teacher at Sea
Christine Hedge
Onboard USCGC Healy
August 7 – September 16, 2009

Mission: U.S.-Canada 2009 Arctic Seafloor Continental Shelf Survey
Location: Beaufort Sea, north of the arctic circle
Date: August 14, 2009

Weather Data from the Bridge
80⁰ 3’N 145⁰ 42’W
Temp: 31⁰ F Light, fine snow

Science and Technology Log

Some of you have asked what the ice looks like up here. Pull out your maps and I’ll tell you about the changing ice conditions. When I got to Barrow on 8/4/09 there was no ice visible from shore. But this changes with the winds and currents. Just one day earlier, the coastline was lined with chunks of sea ice but it had blown out to sea by the time I flew in.

As we started sailing north from Barrow into the Chukchi Sea we saw some chunks of ice but mostly dark water. Our track line (the path we follow) took us back and forth, north and south as we tested our equipment and waited to meet up with our partner ship from Canada. As we went south, there were more patches of open water. Traveling north brought us into more ice.

What looks like dirt is really a layer of algae

Sometimes there were large patches of open water and sometimes it looked like ice all the way to the horizon. The ice that appears blue has frozen and thawed over a period of time. When it freezes, the salt is squeezed out leaving behind fresher, bluer water. The dark lines on the ice are patches of algae that grow at the interface between the ocean water and the sea ice. The sea ice of the Chukchi and Beaufort Seas has retreated as far north as it will go generally by September. We are traveling during the best open water time for this part of the world.

Now that we are traveling north, breaking a path for the CCGS Louis S. St. Laurent we are seeing less and less open water. Yesterday, (8/13/09) the view from the deck looked like a white jigsaw puzzle spread out on a black table. Each day there is more and more ice.

Today, (8/14/09) when I look out over the ice it looks like a white landscape with black lakes or rivers meandering through. We passed 80⁰N today and there are more ridges and large expanses of ice. On board ship there are people who are experts in sea ice. Using direct observation and satellite imagery they help the crew know what the ice conditions are going to be. In fact, there is a whole field of study concerning ice. Who knew! If you would like to learn more, visit the website of the National Ice Center (http://natice.noaa.gov). I’ll go into this topic in more detail after I learn more.

Personal Log

My goal for next this week is to learn more about how ice is classified. I found a little book “The Observers Guide to Sea Ice” which will be a good place to start. The many ice experts on board will also be a great resource. We are hearing the sound of ice against the hull of the ship more often now and that is a pretty powerful sound. I can’t imagine what it will be like when we hit thicker ice.

The list of Inupiaq words for snow and ice is long – which makes sense. To someone from Indiana, (like me) there might appear to be 5 or 6 different consistencies and colors of ice. There are 76 Inupiaq words to describe ice! Some refer to its age, composition, position to land and a host of other factors. For example, the word for thin ice that is too dangerous to walk on is sikuaq. Slushy ice piled up on the beach is called qaapaaq.

For my students: Do you have any questions about Ice?

August 12, 2009April 6, 2021

Justin Czarka, August 12, 2009

NOAA Teacher at Sea
Justin Czarka
Onboard NOAA Ship McArthur II (tracker)
August 10 – 19, 2009

Mission: Hydrographic and Plankton Survey
Geographical area of cruise: North Pacific Ocean from San Francisco, CA to Seattle, WA
Date: August 12, 2009

Weather Data from the Bridge

Sunrise: 06:25 a.m.
Sunset: 20:03 (8:03 p.m.)
Weather: isolated showers/patchy coastal fog
Sky: partly cloudy
Wind direction and speed: North 10-15 knots (kt)
Visibility: unrestricted to less than 1 nautical mile (nm) in fog
Waves: northwest 4-6 feet
Air Temperature: 17.3 °C
Water Temperature: 16.6 °C

Science and Technology Log

Justin Czarka collects water samples to use in nutrient and chlorophyll research. While on the deck during “ops” (operation) all personnel must wear a life jacket and hardhat.

This log discusses the purpose behind the scientific cruise aboard the McArthur II. The cruise is titled, “Hydrographic and Plankton Survey.” The cruise is part of a larger study by many scientists to, in the words of chief scientist, Bill Peterson, “understand the effects of climate variability and climate change on biological, chemical and physical parameters that affect plankton, krill, fish, bird and mammal populations in Pacific Northwest waters.” This specific cruise focuses on hydrology, harmful algal blooms, zooplankton, krill, fish eggs, fish larvae, and bird and mammal observations.

I will provide an overview of these aspects of the cruise. The McArthur II is set up with sensors for salinity, temperature, and fluorescence that provide a continuous monitoring of the ocean (hydrology) throughout the cruise. In addition at various points along the transect lines (see the dots on the diagram of the cruise route on page 2), the CTD is deployed into the water column at specific depths to determine salinity (via measuring conductivity), water temperature, and depth (via pressure), and collect water samples (which we use to measure chlorophyll and nutrient levels at specific depths). The transects (predetermined latitudes that forms a line of sampling stations) have been selected because they have been consistently monitored over time, some since the late 1980s. This provides a historical record to monitor changes in the ocean environment over time.

The dots represent planned sampling station. Due to sea conditions, these have been slightly modified.

One scientist, Morgaine McKibben from Oregon State University, is researching harmful algal blooms (HAB). HABs occur when certain algae (the small plants in the ocean that are the basis of the food web) produce toxins that concentrate in animals feeding on them. As these toxins move up the food web through different species, they cause harmful effects in those species, including humans. Bill Peterson (NOAA/ Northwest Fisheries Science Center) and Jay Peterson (OSU/Hatfield Marine Science Center) are studying copepod reproduction. They are collecting data on how many eggs are laid in a 24 hour period, as well as how the copepod eggs survive in hypoxic (low oxygen) conditions. Mike Force, the bird and marine mammal observer is keeping a log of all species spotted along the cruise route, which is utilized by scientists studying the species.

Personal Log

Tiny squid collected in a vertical net and viewed under microscope on Crescent City transect line at 41 deg 54 min North.

Who said you never find the end of the rainbow? All you have to do is go out to sea (or become a leprechaun!). We have been going through patches of fog today, putting the foghorn into action. When it clears out above, yet is foggy to the horizon, you get these white rainbows which arc down right to the ship. We have become the pot of gold at the end of the rainbow. Who knew it was the McArthur II! If you follow the entire rainbow, you will notice that it makes a complete 360° circle, half on top the ocean and half in the atmosphere near the horizon.

I enjoyed using the dissecting microscope today.

The water collected from the vertical net is stored in a cooler on the deck to be used in experiments. I was able to collect a sample of the water, which contained a diverse group of organisms, from tiny squids to copepods to euphausiids. These tiny organisms from the size of a pinhead to a centimeter long are critical to the diets of large fish populations, such as salmon. Under magnification, one can see so much spectacular detail. I have learned how essential it is to have an identification guide in order to identify the names of each copepod and euphausiid. On the other hand the scientists tend to specialize and become very adept at identifying the different species.

Animals Seen Today

Arrow worms (long clear, with bristles)
Shrimp Copepods
Tiny rockfish (indigo colored eyes)
Fish larvae

August 11, 2009April 6, 2021

Justin Czarka, August 11, 2009

NOAA Teacher at Sea
Justin Czarka
Onboard NOAA Ship McArthur II (tracker)
August 10 – 19, 2009

Mission: Hydrographic and Plankton Survey
Geographical area of cruise: North Pacific Ocean from San Francisco, CA to Seattle, WA
Date: August 11, 2009

Weather data from the Bridge

Sunrise: 6:25 a.m.
Sunset: 20:03 (8:03 p.m.)
Weather: partly cloudy
Sky: patchy fog
Wind direction and speed: Northwest 5-10 knots
Visibility: unrestricted to less than 1 nautical mile (nm) due to fog
Waves: 5-7 feet
Air Temperature: 15° Celsius
Water Temperature: 12.92 °Celsius

Science and Technology Log

The McArthur II took about six hours from leaving port in San Francisco to reach our first station at Bodega Bay. We arrived at Bodega Bay around midnight. Bodega Bay, along with the next three stations, Point Arenas, Vizcaino Canyon, and Trinidad Head, California, will be sampled at only one station location each as we move up the coast to reach our first transect line of nine stations off Crescent City, California (Latitude: 41 deg 54 min). Due to leaving port later than expected, the science team has dropped some of the sampling sites at the southern end of the cruise. Still we are sampling as we head north in order to get an enhanced survey picture along a north-south line. At the stations, we are dropping the CTD into the water column, using the vertical net, and the bongo net.

Jennifer Menkel and Lacey O’Neal observe the CTD deployment. The left screen display depth sounds on three different frequencies, the middle screen creates graphs based on the CTD sensors, and the right screen shows live video feed of the CTD deployment on the fantail (back deck) of the McArthur II.

While I did not participate in the first sampling at Bodega Bay, my shift (read more about shifts below) began sampling at Point Arenas and then Vizcaino Canyon. Upon entering the dry lab, Jay Peterson and Jennifer Menkel, both of Oregon State University, Hatfield Marine Science Center (OSU/HMSC) in Newport, Oregon, were observing the data stream for the CTD on the computer monitors with McArthur II senior survey technician Lacey O’Neal. Communication is essential. The scientists are looking at the TV monitors for the CTD deployment outside, altimeter (measures the CTD’s height above the seafloor), depth below the surface, and communicating with both the ship’s officers on the bridge, who are navigating the boat, and crew who are working the winches. Everyone has to work together to ensure that the CTD is deployed and retrieved safely. Otherwise, it could potentially hit the ship, causing damage to the ship, crew, and/or CTD sensors. I am appreciating the emphasis on collaboration that occurs for the benefit and safety of the scientific research occurring on the ship.

I will discuss the sample collection technique for the chlorophyll. The main purpose for measuring the chlorophyll is to determine the chlorophyll composition and suitability for single celled algae to develop. These single celled organisms are the basis of the food chain. By determining the amount of chlorophyll, you can look at the probability of organisms to develop at that location, such as plankton. Plankton succeed where there is enough light to allow photosynthesis to occur. Deni Malouf, a marine science technician from the U.S. Coast Guard, and I put on waders, boots, life jackets, gloves and hardhats. We headed out to the CTD to collect water samples from specific depths. After filling up brown bottles (which prevent exposure to sunlight) with water, we transferred the bottles to the wet lab to pour 100 mL through a filter that collects chlorophyll on top while allowing the water to flow through by utilizing a vacuum. This procedure is done while ensuring that the equipment, filters, and water samples avoid contact with your hands, thus contaminating the sample. After the water has been filtered the filter is placed in a centrifuge tube (vial) with tweezers, covered to avoid exposure to light, and stored in the freezer for lab analysis at a later date. The sample is covered to prevent exposure to sunlight. If not, sunlight could cause more chlorophyll to develop, which would be an inaccurate reading for how much chlorophyll was actually collected at specific depths in the water column at a sampling station.

I am measuring a 100 mL water sample to collect chlorophyll on a filter inside the black cups in the wet lab. These containers have a filter that at the bottom. A vacuum draws the water through white tube, leaving the chlorophyll behind on the filter.

Personal Log

The work conducted aboard the McArthur II, as well as other ships in the NOAA fleet, revolves around a schedule of watches (a watch is a shift). Crewmembers work on the McArthur II in four or eight hour watches. The time of day and length vary for different crewmembers. As for the science team, Bill Peterson, our chief scientist (cruise leader) from NOAA/ Northwest Fisheries Science Center (NWSC), Newport, Oregon, arranged us into 12-hour watches. There is a day watch and night watch. I am part of the day watch, which commences at 7:00 a.m. and ends at 7:00 p.m. You muster (show up) about a half hour before your watch begins so that the previous watch knows you are ready to begin work, and to assist as needed with the end of the previous watch. My watch is comprised of Jay Peterson, Jennifer Mendel, and myself. There is a lot of teamwork and cooperation within the watches. Even this morning, Deni Malouf, who had been working the night watch, stayed on for a portion of the day watch to assist me with the protocol for filling up the water samples from the CTD, for preparing chlorophyll samples, and for setting up the Niskin bottles on the CTD to be deployed at the next station.

Vocabulary

*Dry lab- in the back of the O-1 deck (one of the floors on the ship above the waterline) where the computer equipment is situated. Used to monitor CDT deployment.*

*Wet lab-an indoor lab in the back of the O-1 deck connected where water samples are tested. Contains sinks, freezers, refrigerators, and science equipment.*

*Vertical net- a net deployed vertically through the water column at one specific location. Has a weight on the bottom of it to maintain its shape on the way through the water column.*

Bongo net- a net for collecting organisms, that appears to look like a set of bongo drums. Attached to a cable and the J frame, deployed off the side of the boat, and collects samples as the boat trawls at a specific speed to maximize the collection.

July 16, 2009April 5, 2021

Dan Steelquist, July 16, 2009

NOAA Teacher at Sea
Dan Steelquist
Onboard NOAA Ship Rainier
July 6 – 24, 2009

Mission: Hydrographic Survey
Geographical Area: Pavlov Islands, Gulf of Alaska
Date: July 16, 2009

Weather Data from the Bridge

Latitude: 55°13.522’ N Longitude: 161°22.795’ W Visibility: 10 Nautical Miles Wind Direction: 174° true Wind Speed: 15 knots Sea Wave Height: 0-1ft. Swell Waves: N/A Water Temperature: 8.3° C Dry Bulb: 10.6° C Wet Bulb: 10.6° C Sea Level Pressure: 1021.0 mb

Science and Technology Log

The primary mission of the Rainier is to gather hydrographic sounding data. For this leg of the summer field session, that data collection is done by a number of small launches that go out to work each day from Rainier. On a typical day four twenty-nine foot survey launches are deployed from the ship, each with an assigned area to gather data. Each launch is equipped with a multibeam sonar device that sends sound signals to the bottom and then times how long it takes for the signal to return to the receiver. Knowing how fast the signal will travel through the water, the length of time the signal takes to leave and return to the sounder determines the depth of the water at that point.

Here I am preparing the CTD to take a cast.

For many years sonar devices have only been able to measure the water depth directly below a survey vessel. Now, with multibeam sonar, survey vessels can cover a larger swath of seafloor with hundreds of depth measurements being taken at a time. Once the data is processed, a “painted” picture of the bottom surface can be generated. Once a launch is in its assigned work area, the sonar is turned on and the boat goes back and forth in a prescribed pattern to gather data on water depth, essentially providing total coverage of what the seafloor looks like in that area. The coxswain (person driving the launch) has a computer screen with a chart of the coverage area and steers the launch over the planned area. As the launch moves along the path of sonar coverage its path shows up on the screen as a different color, letting the driver know where the boat has been.

In order for data to be interpreted accurately, there are many steps in the process from data acquisition to actual placement on a nautical chart. There is one very important piece of data that needs to be gathered in the field as the launches do there work with the sonar. Sound waves can vary in speed as they travel through water, depending on certain conditions. In order for accurate depth readings to be acquired, those conditions must be known. Therefore throughout the data gathering session, hydrographers must acquire data on the condition of the water. That is where a CTD cast comes in. CTD stands for conductivity, temperature, depth. Every few hours a CTD cast must be done in order to accurately interpret the data gathered by the sonar. The device is lowered over this side of the launch and allowed to sink to the bottom. As it descends, the CTD gathers data at various depths. When recovered the CTD is connected to a computer and its data is integrated with the sonar data to acquire more accurate depth readings.

Personal Log

I’ve been on the Rainier now for twelve days. While there are certain routines on board the ship, there isn’t much routine about the work these people do. I continue to be impressed with how everyone applies their skills to their work in order for data to be gathered. Much of the area where we are working has never been charted before and much of what has been charted was done before World War II with lead lines (dropping a piece of lead attached to a line, and counting the measured marks on the line until it hits bottom). The details acquired by multibeam sonar are truly amazing. We will be here in the Pavlof Islands for a few more days and then head back to Kodiak, where I will get off the ship. Not long to go, but there is still much for me to learn!

Something to Think About
How long would it take you to paint an entire house with dots from a very small paintbrush? That would be like using a lead line to gather depth information. How long would it take you to paint an entire house with a very small, narrow paint brush? That would be single beam sonar. How much time could you save by using a wide paintbrush? That would be multibeam sonar.

May 12, 2009April 5, 2021

Lollie Garay, May 12, 2009

NOAA Teacher at Sea
Lollie Garay
Onboard Research Vessel Hugh R. Sharp
May 9-20, 2009

Mission: Sea scallop survey
Geographical Area: North Atlantic
Date: May 12, 2009

Weather Data from the Bridge
High pressure ridge building late today until wed
Temperature: 12.22˚ C
True winds: 5KTS Seas: 2-4 ft.

Science and Technology Log

As soon as our shift began today, the dredge was already on deck so we went straight to work. After several stations I noticed that the scallop and crab count was lower than yesterday. We are working in an area called Elephant Trunk. It is named this because the bathymetry of the sea floor makes it look like one. We have many stations in this Closed area, so we may see an increase in scallop numbers as the shift progresses.

Today I learned about “clappers”. Clappers are scallop shells that have no meat in them. They are sorted out from the rest and counted. I asked Vic Nordahl why they were important and he said that clappers give us an estimation of natural mortality or predation, so they need to keep count of how many are found.

Can you see the Red Hake tucked in the scallop shell?

Between dredges today, I spoke with Wynne Tucker. Wynne is an oceanographic tech from the University of Delaware and is in her third season on this research vessel. Wynne does a CTD cast every third station. A CTD measures conductivity, temperature, and depth. She takes samples in the water column at depths of 50-70M. Sensors on the CTD send information to a computer where the data is recorded. The CTD also records information about fluorescence, presence of particulates, and oxygen. The data gives us a visual of the water column which is then sent to NOAA (the National Oceanic and Atmospheric Administration) for analysis. When Wynne is not doing CTD casts, she is working at many different jobs Larry Brady and I processed some special samples this evening. We usually measure 5 scallops. Two of the samples had a larval or young Red Hake inside. It lives inside the scallop shell for protection from predators and is tucked on one side of it. This is not a symbiotic relationship, rather more commensalism. I continue to be amazed about the life systems in these waters!

Personal Log

Elise Olivieri (the teacher from New York) and I have made plans to photograph each other as we work. We work different 12 hour shifts so we do not see each other except during the shift change. And as we have both learned, there is not time for picture taking once the work begins! Unfortunately, our pictures will not be included in our journals at this time, but will be added upon our return!

My day ended with two incredible sights. First, as I carried the special samples up to the storage cage, I looked out from the portside at a totally dark scene. You could not make out sky or sea- it all blended into …black! I have never seen anything quite like that before. The second occurred on the starboard side just as I was ending my shift. Glen Rountree (NOAA Fisheries Service volunteer) told me he had seen a strange red light in the sky and after looking through his binoculars realized it was the Moon. Elise and I grabbed our cameras and went out on deck. It was beautiful! One solitary red light in the middle of black! It was a good way to end the day.

Question of the Day
What is the difference between symbiosis and commensalism?

Animals Seen Today
Spider Crab, Sea Squirts, Gulf Stream Flounders, and Bobtail Squid.