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Diana Griffiths, June 24, 2006

NOAA Teacher at Sea
Diana Griffiths
Onboard UNOLS Ship Roger Revelle
June 22 – June 30, 2006

Mission: Hawaiian Ocean Timeseries (WHOTS)
Geographical Area: Hawaiian Pacific
Date: June 24, 2006

Weather Data from Bridge 
Visibility:  10 miles to less than 25 miles
Wind direction:  065°
Wind speed: 06 knots
Sea wave height: small
Swell wave height:  4-6 feet
Sea level pressure: 1014.5 millibars
Cloud cover:  3, type:  stratocumulus and cumulus

Buoy Technician, Sean Whelan, contacting the Acoustic Releases on WHOTS-2.
Buoy Technician, Sean Whelan, contacting the Acoustic Releases on WHOTS-2.

Science and Technology Log 

Today was very busy because it was the day that WHOTS-2 mooring, which has been sitting out in the ocean for almost a year, was recovered.  At around 6:30 a.m., Sean Whelan, the buoy technician, tried to contact the Acoustic Release.  (The Acoustic Release is the device that attaches the mooring to the anchor. When it receives the appropriate signal, it disengages from the anchor, freeing the mooring for recovery.  There are actually two releases on WHOTS2.) He does this by sending a sound wave at 12 KHz down through the ocean via a transmitter, and when the release “hears” the signal, it returns a frequency at 11 KHz. The attempt failed, so the ship moved closer to the anchor site and the test was repeated.  This time it was successful.  Based on the amount of time it takes the acoustic signal to return, the transmitter calculates a “slant range” which is the distance from the ship to the anchor. Because the ship is not directly over the anchor, this slant range creates the hypotenuse of a right triangle. Another side of the triangle is the depth of the ocean directly below the ship.  Once these two distances are known, the horizontal position of the ship from the anchor can easily be calculated using the Pythagorean theorem.

Recovery of WHOTS-2 buoy aboard the R/V REVELLE.
Recovery of WHOTS-2 buoy aboard the R/V REVELLE.

After breakfast, the buoy recovery began. A small boat was lowered from the ship and driven over to the buoy, as the ship was steamed right near the buoy. A signal was sent down to activate the Acoustic Releases. Ropes were attached from the buoy through a pulley across the A-frame, located on the stern of the ship, to a large winch.  With Jeff Lord leading the maneuvering of the 3750-pound buoy, it was disengaged from the mooring and placed safely on deck.  This was a bit of a tense moment, but Jeff did a wonderful job of remaining calm and directing each person involved to maneuver their equipment to effectively place the buoy. Once the buoy was recovered and moved to the side of the deck, each instrument on the mooring was recovered.  The first to appear was a VMCM, (Vector Measuring Current Meter) located just 10 meters below the buoy.

Jeff Lord, engineering technician, directing the recovery of a Vector Measuring Current Meter (VMCM).
Jeff Lord, engineering technician, directing the recovery of a Vector Measuring Current Meter (VMCM).

Then two microCATs were pulled up, located 15 and 25 meters below the buoy, followed by a second VMCM. This was followed by a series of eleven microCATs located five or ten meters apart, an RDI ADCP (Acoustic Doppler Current Profiler), and two more microCATs.  As each instrument was recovered, the time it was removed from the water was recorded and its serial number was checked against the mooring deployment log.  Each instrument was photographed, cleaned off and sent to Jeff Snyder, an electronic technician, for data upload. Each of these instruments has been collecting and storing data at the rate of approximately a reading per minute for a year (this value varies depending on the instrument) and this data now needs to be collected. Jeff placed the instruments in a saltwater bath to simulate the ocean environment and connected each instrument to a computer by way of a USB serial adaptor port. The data from each instrument took approximately three hours to upload. Tomorrow, these instruments will be returned to the ocean alongside a CTD in order to compare their current data collection with that of a calibrated instrument.

Once all of the instruments were recovered, over 4000 feet of wire, nylon rope, and polypropylene rope were drawn up using a winch and a capstan. Polypropylene rope is used near the end of the mooring because it floats to the surface.  The last portion of the mooring recovered was the floatation.  This consisted of eighty glass balls chained together and individually encased in plastic. The glass balls, filled with air, float the end of the mooring to the surface when the Acoustic Releases disengage from the anchor.  It takes them about 40 minutes to reach the surface. Recovering the glass balls was tricky because they are heavy and entangled in one another. Once on deck they were separated and placed in large metal bins. After dinner, a power washer was used to clean the buoy (it is a favorite resting place for seagulls and barnacles) and the cages encasing some of the instruments.  The deck was cleaned and organized to prepare for tomorrow.

Recovery of mooring floatation on WHOTS-2, consisting of 80 glass balls encased in plastic.
Recovery of mooring floatation on WHOTS-2, consisting of 80 glass balls encased in plastic.

Personal Log 

The theme that keeps going through my mind during this trip and today especially, is how much of a cooperative effort this research requires. It begins with the coordination between Dr. Weller and Dr. Lukas to simultaneously collect atmospheric data using the buoy and subsurface data with the mooring instruments. In addition, Dr. Frank Bradley, an Honorary Fellow at the CSIRO Land and Water in Australia, is on the cruise working to create a manual set of data points for relative humidity using an Assman psychrometer to further check the relative humidity data produced on the buoy. Within the science teams, coordination has to occur at all stages, from the collection of data to its analysis. This was very evident in physical form today with numerous people on deck throughout the day working to retrieve the mooring, fix machinery as it broke down (the winch stopped twice), and clean the instruments.  In the labs, others were working to upload data and configure computer programs to coordinate all of the data.  In addition to all of this is the quiet presence of the ship’s crew who are going about their duties to be sure that the ship is running smoothly.  Several of the crew did take a break today just after the instruments were collected in order to put out fishing lines!  They caught numerous tuna and beautiful Mahi Mahi that the cook deliciously prepared for dinner.

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Diana Griffiths, June 22, 2006

NOAA Teacher at Sea
Diana Griffiths
Onboard UNOLS Ship Roger Revelle
June 22 – June 30, 2006

Mission: Hawaiian Ocean Timeseries (WHOTS)
Geographical Area: Hawaiian Pacific
Date: June 22, 2006

Weather Data from Bridge 
Visibility:  10 miles to < 25 miles
Wind direction:  080°
Wind speed:  12 knots
Sea wave height: small
Swell wave height: 2-4 feet
Sea level pressure:  1016 millibars
Cloud cover: 5
Cloud type: cumulus, stratocumulus

WHOTS –3 buoy during transfer from 2nd to 1st deck.
WHOTS –3 buoy during transfer from 2nd to 1st deck

The Cruise Mission 

The overall mission of this cruise is to replace a mooring anchored north of the Hawaiian island of Oahu. It’s called the WHOTS buoy: The Woods Hole Oceanographic Institution (WHOI) Hawaii Ocean Timeseries (HOT) Site (WHOTS). The mooring consists of a buoy that contains numerous meteorological sensors that collect data on relative humidity, barometric pressure, wind speed and direction, precipitation, short and long wave solar radiation, and sea surface temperature.  The buoy serves as a weather station at sea, one of few such stations in the world.

There are two of each type of sensor on the WHOTS-3 buoy to ensure that data collection will continue should a sensor break down.  The buoy is equipped with a GPS unit. The buoy also serves as a platform for observing the ocean. Hanging below the buoy are four different types of instruments.  These include SeaCATs, MicroCATs, an ADCP and NGVM. The SeaCATs and MicroCATs take salinity and temperature measurements.  The MicroCATs, in addition to salinity and temperature, also take depth measurements. There are several of each instrument attached to the mooring and they are located approximately 5 meters apart down to a depth of 155 meters.  (The WHOTS-2 mooring only contains MicroCATs). The ADCP or Acoustic Doppler Current Profiler is an instrument that allows the scientists to measure the velocity of the current at a set of specific depths. The NGVM is a New Generation Vector Measuring device that measures the velocity of the current at fixed points using propeller sensors located at 90° to one another. Finally, two Acoustic Release Devices are attached to the anchor that is holding the mooring in place.

SeaCATs being prepared for mooring.
SeaCATs being prepared for mooring.

These instruments allow the scientists to determine the location of the anchor and will also mechanically release the mooring from the anchor when sent a specific acoustic signal. (More about how these work in a later log).  The WHOTS-2 mooring has been sitting in the ocean for a year collecting data.  It is powered by 4000 D-cell batteries and is capable of running off of them for about 16 months.  I asked Jason Smith, the lead instrument calibration technician, why solar panels weren’t used on the buoy and he told me that they are susceptible to being shot at or stolen.  Evidently anything that looks valuable in the middle of the ocean is vulnerable to theft!

Personal and Science Log 

R/V REVELLE’s resident technician, Cambria Colt, operating the crane used to move the WHOTS-3 buoy to the main deck of the ship.
R/V REVELLE’s resident technician, Cambria Colt, operating the crane used to move the WHOTS-3 buoy to the main deck of the ship.

After arriving in Hawaii on the afternoon of Monday, June 19th, it feels good to be at sea on a moving vessel.  I spent the remainder of Monday meeting the science crew from WHOI (Woods Hole Oceanographic Institution) led by the Chief Scientist, Dr. Robert Weller, having a nice dinner and falling asleep after a long day of travel.

Tuesday brought my first view of the REVELLE, a working science vessel owned by the SCRIPPS Institution of Oceanography in La Jolla, California. Go here for diagrams, pictures and statistics describing this ship. The ship has two platforms below the main deck and three decks above, not including the bridge. The main deck contains heavy equipment consisting of several winches, a crane, an electric winding cart and other machinery designed to move heavy objects. All of this equipment operation is run or overseen by Cambria Colt, the resident technician, who knows the ship like the back of her hand.  It is her primary job to act as a liaison between the ships’ crew and the scientists, making sure that the needs of the science team are met. We were at the ship by 7:30 a.m. and the team started working, preparing for the cruise.

Many of the team members had already been here for a week unloading and working with the instruments.  The team works well together – everyone keeps busy and seems to know what to do without a lot of discussion. I helped Jason to string up two GPS units on an upper deck of the stern of the ship as well as an antenna.

GPS units set up by science team on stern of R/V REVELLE.
GPS units set up by science team on stern of R/V REVELLE.

The antenna is used to transmit all of the data from the mooring and from the ship to a satellite, which then directs it to WHOI.  I also recorded measurements as Sean Whelan, the buoy technician, measured the distances from the top of the buoy to all of the instruments located on the buoy. He also wrapped bird wire repellant along the top of the tower of the buoy in an attempt to keep birds from landing on the instruments.  The bird wire is spiky wire that jets out in various directions and can be quite treacherous to work with!  Along the deck, Jeff Lord, an engineering technician, and Scott Burman, an undergraduate volunteer, worked on bolting down numerous winches to the deck that will be used to pull the buoy out of the water.  Several winches are used on all sides to maintain maximum control over whatever is being maneuvered into or out of the water.

I also met the captain of the ship, Tom Desjardins, in the afternoon.  I had no idea he was the captain when I first saw him, he was working hard on deck with the rest of the crew, clad in a T-shirt and shorts.  He is quite affable, calm, and willing to put in a hand where it is needed. In a quick discussion with him I learned that security has become much tighter on the ship since 9/11. There are always two people on watch at the entrance to the ship when it is in port making sure that everyone who enters and leaves is accounted for. We all wear badges when we are on ship when it is in port.  I also asked him about potable water use on the ship. The ship can hold 12,000 gallons of water and up to 3,000 gallons more can be distilled per day.  Heat from the ship’s engines is used to distill the water.

I had Wednesday free to do a bit of sightseeing and that leads me back to today.  We packed our clothes onto the ship early this morning and made up our berths (beds).  The staterooms (bedrooms) are larger than I had expected.  I have my own room and share a head (bathroom) with Terry Smith, another member of the team.  Terry is also an undergraduate who won the NOAA Hollings Scholarship to participate on this cruise.  Currently working towards a second career, Terry was a chef for 20 years before making the plunge to study science. She is working towards a degree in geo-oceanography.  During the day I was able to get a computer set up and mostly watched and asked a few questions as more work was being done. The ship left port at 4:00 p.m.  After taking a few pictures and watching the beauty of the coast slip away, I went back inside to attend a meeting led by Cambria and Dr. Weller.

Life Aboard Ship 

Cambria talked about safety and reviewed some basics about living on the ship.  We wear closed toed shoes at all times (except in our rooms), preferably steel-toed.  When we are working on deck during the scientific operations we will wear hard hats and safety vests.  Tomorrow there will be a safety drill at some point to be sure we all know where to “muster” and how to proceed should a fire or other problem occur on the ship.  We separate our trash here – anything plastic and non-biodegradable has a separate bin.  All of the paper and food waste, etc, has its own bin and is eventually tossed into the sea.  Meals are at specific times during the day (and they are quite good!) but we are asked to “eat and run”, as the galley crew needs to get on with their work of cleaning up and preparing for the next meal or just getting some time off.  The ship is equipped with a laundry and an exercise room.  Evidently on long cruises members of the crew can be seen running laps around the main deck.

Vocabulary – Weather Data 

Wind direction: Wind direction is measured in degrees, which follow the readings on a compass.

Wind speed:   Measured in knots. A knot is 1 nm/hr.  A nautical mile is the distance required to travel 1° longitude.  It is equivalent to 1.85 km.

Sea wave height: This is the height of waves produced by the wind.  This is logged in the ships log as either small or slight.  The technical formula for sea wave height is .026 x (speed of wind)2.

Swell wave height: This is the height of the swells produced by distant weather patterns. Swells form a wave pattern as opposed to sea waves, which are more random.  Swell wave height is measured in feet.

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Eric Heltzel, October 19, 2005

NOAA Teacher at Sea
Eric Heltzel
Onboard NOAA Ship Ronald H. Brown
September 25 – October 22, 2005

Mission: Climate Observation and Buoy Deployment
Geographical Area: Southeast Pacific
Date: October 19, 2005

Weather Data from Bridge

Temperature: 25.5 degrees C
Clouds cover: 6/8, stratus, altocumulus
Visibility: 12 nm
Wind direction: 245 degrees
Wind speed: 13kts.
Wave height: 3 – 5’
Swell wave height: 3 – 5’
Seawater Temperature: 28.7 degrees C
Sea level Atmospheric pressure: 1005 mb
Relative Humidity: 82%

Science and Technology Log 

Sailing on the RONALD H. BROWN as a NOAA Teacher at Sea has been an opportunity to experience scientific research first hand.  I have been impressed by the commitment to excellence exhibited by all members of the scientific teams.  They have undertaken the design and logistical challenges of the Stratus 6 cruise with great attention to detail, absolute commitment to execution of the plan, and countless hours of effort.  Tasks were carried out with a high degree of professionalism and in good humor.

The officers and crew of the BROWN were not only generous and considerate, they were very competent.  People knew their jobs and did them without complaint.  There seems to be an enthusiasm for the research that the ship facilitates.  Throughout the cruise I felt confident that the ship was in good hands.

Going to sea for the first time has been a challenge for me.  As with many things that push us outside our comfort zone and away from the familiar, learning is fast paced and intense.  This will be my last log from the RONALD H. BROWN.  I wish to thank the Teacher at Sea program of NOAA for making this experience possible.  Thanks to Captain Tim Wright and the officers and crew of the BROWN for helping this previously land-locked teacher from Wyoming have a great experience.  Special thanks to Dr. Bob Weller and the team from Woods Hole Oceanographic Institution for taking me under their wings and answering my numerous questions.  Thanks to Peggy Decaria for substituting for me in my classes at Evanston High School.  I never would have been able to have this experience if not for the support of Superintendent Dennis Wilson and all of Uinta County School District #1.  I’m going back to school with a rich experience to share, new resources to facilitate my teaching, and many new ideas.  Thanks to you all.

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Eric Heltzel, October 18, 2005

NOAA Teacher at Sea
Eric Heltzel
Onboard NOAA Ship Ronald H. Brown
September 25 – October 22, 2005

Mission: Climate Observation and Buoy Deployment
Geographical Area: Southeast Pacific
Date: October 18, 2005

Weather Data from Bridge

Temperature: 25.5 degrees C
Clouds cover: 6/8, stratus, altocumulus
Visibility: 12 nm
Wind direction: 245 degrees
Wind speed: 13kts.
Wave height: 3 – 5’
Swell wave height: 3 – 5’
Seawater Temperature: 28.7 degrees C
Sea level Atmospheric pressure: 1005 mb
Relative Humidity: 82%

Science and Technology Log 

Rodrigo Castro and Carolina Cisternas are research technicians from the University of Concepcion in Concepcion, Chile.  They joined the cruise at Panama City and have been taking ocean water samples every 60 nm.  Their samples are run through 0.7 and 0.2 micron filters.  They capture and freeze particulate organic mater by this process and take it back to the lab at the university.  The samples are analyzed for the presence of stable isotopes of carbon and nitrogen.  These samples are then used as biomarkers to help determine the circulation of ocean water.  A second analysis will be going on to locate the gene associated with nitrogen-fixing organisms.  This is new ground for the scientists at the university.

Upwellings are areas where deep ocean water comes to the surface.  According to Rodrigo and Carolina there are four significant areas of upwelling along the Chilean coast. The two most northerly are found at 20 degrees south and 24 degrees south.  These are active year round and are slow and steady with no significant seasonal fluctuation. Another at 30 degrees south is moderate in nature with some seasonal variation, being more active during the summer.  The most southerly is at 36 degrees south and is strong September to April. However it mostly disappears the rest of the year. Upwelling zones are recognizable because of their cooler water temperature.  They also have increased nutrients that are brought up from the deep and a higher amount of chlorophyll due to increased photosynthetic activity.  Some fish species are found in greater abundance in these zones due to increased nutrients extending into more food availability.

Personal Log 

The RONALD H. BROWN is under way. We are steaming in an easterly heading on the leg of the cruise that will take us to Arica, Chile.  It is a bit of a challenge for me, as we are no longer headed into the direction of the swells; instead, we are crossing them at a 30-degree angle, which makes for more oscillations in the movement of the ship.  My tummy is being challenged.

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Eric Heltzel, October 14, 2005

NOAA Teacher at Sea
Eric Heltzel
Onboard NOAA Ship Ronald H. Brown
September 25 – October 22, 2005

Mission: Climate Observation and Buoy Deployment
Geographical Area: Southeast Pacific
Date: October 14, 2005

Weather Data from Bridge
Temperature: 19 degrees C
Sea level Atmospheric pressure: 1016 mb
Relative Humidity: 70%
Clouds cover: 8/8, stratocumulus
Visibility: 12 nm
Wind direction: 120 degrees
Wind speed: 16kts.
Wave height: 3 – 4’
Swell wave height: 4 – 5’
Swell direction: 120 degrees
Seawater Temperature: 18.3 degrees C
Salinity: 35 parts per thousand
Ocean depth: 4364 meters

Science and Technology Log 

A big day today! We managed to deploy the Stratus 5 buoy.  It was basically the reverse of our retrieval. The buoy was tipped up 45 degrees and the top 35 meters of instruments were hooked together.  Next the mooring was attached to the buoy and it was placed in the water with a crane. This phase was done off of the portside of the fantail.  We held the wire that was attached to the buoy and let it swing out behind the ship.  Then using a large winch we would play out more of the cable, stop, secure the line, and then attach the next instrument.  Consider the fact that if we were to lose hold of the mooring we could lose the whole works into 4000 + meters of ocean water.  It’s not like working on land where if you drop something, you say whoops and pick it up again.  If that happens on the ship the thing you drop may well go over the side.  Serious Whoops!

Once all of the instruments were attached we started paying out nylon and polypropylene line. This was accomplished by using an H-bit to run the line through.  The line was in 4’ x 4’ x 4’ boxes and trailed out into the ocean as the ship moved forward at just over one knot. When we got to the end of the line it was time to attach the new acoustic releases so that this buoy can be recovered next year.  Then it was time for the big splash. The mooring was attached to the anchor which was made up of three iron disks, twelve inches thick and three feet in diameter.  The anchor’s weight is 9000 pounds. The anchor was sitting on a steel plate and the stern of the fantail.  A crane picked up the forward edge of the plate and tipped the anchor into the ocean.  The splash from the six-foot drop to the water went twenty feet in the air.  The anchor started the trip to the bottom dragging all of the mooring and the buoy.  The falling anchor pulled the buoy at about four knots towards the anchor location.  Excited cheers went up on the fantail. The Stratus 5 buoy had been successfully deployed!

Instruments Deployed (top 450 meters)

Deployed on the mooring line beneath the buoy: MICRO CAT temperature, salinity SEA CAT temperature, salinity Brancker temperature, salinity VMCM direction, velocity of water flow NORTEK acoustic Doppler current profiler T-POD   temperature logging device SONTEK acoustic Doppler current meter RDI ADCP acoustic Doppler current profiler (125 m) SDE 39 temperature logging device Acoustic release just above the anchor

On the buoy: (this information is transmitted 4 times a day) Atmospheric pressure, Air temperature, Wind speed and direction, Relative humidity, Precipitation, Long wave radiation, Short wave radiation, Sea surface temperature and salinity.

You may notice that many of the instruments on the mooring measure the same thing.  This redundancy is intentional guaranteeing verifiable data.  There are two complete meteorological systems on the buoy.

Response to Student Questions 

Does the stratus layer extend to the land?

After questioning the senior scientists about this the answer is yes.  We are at about 20 degrees south. Here there is a daily fluctuation in the cloud cover.  It often dissipates during the afternoon as a result of warming by the sun.  Apparently the coast of northern Chile often has a cloud layer that also dissipates during the day.  This can be low-lying enough to be fog. As you travel a few miles inland and up in elevation you are no longer under the stratus layer.

Does the stratus layer affect El Nino?

Ocean and atmosphere constantly influence each other.  I have to do more inquiry to give a solid answer to this question.

Note: There is some confusion about the labels being used for the buoy and the cruise.  This is the sixth Stratus Project cruise which is deploying the fifth Stratus buoy.  Hence, the Stratus 6 cruise is recovering the Straus 4 buoy and deploying the Stratus 5 buoy.