Jacquelyn Hams: 7 November 2011

NOAA Teacher at Sea
Jackie Hams
Aboard R/V Roger Revelle
November 6 — December 10, 2011

Mission: Project DYNAMO
Geographical area of cruise: Leg 3, Eastern Indian Ocean
Date: November 7, 2011

Weather Data from the R/V Revelle Meteorological Stations

Time: 1100
Course on Ground
Wind Direction:   195.50
Wind Speed (m/s):   2.1
Air Temperature (C):  27.6
Relative Humidity:   81.7%
Dew Point: (C):   24.4
Precipitation (mm):   6.0

PAR (Photosynthetically Active Radiation) (microeinsteins): 517.4
Long Wave Radiation (w/m2): 405.3
Short Wave Radiation (w/m2): 60.5                                                                            

Surface Water Temperature (C): 28.7
Sound Velocity:  1540.6
Salinity (ppm): 32.45
Fluorometer (micrograms/l): 65.2
Dissolved Oxygen (mg/l): 3.6

Wave Data from WAMOS Xband radar

Wave Height (m) 1.6
Wave Period (s): 18.4
Wavelength (m):  312
Wave Direction:   2650

Science and Technology Log


Leg 3 of the Project DYNAMO research cruise began, on November 6, 2011 from Phuket, Thailand at approximately 1430. The DYNAMO Leg 3 research cruise consists of seven scientific groups conducting experiments in the following areas:

  • Surface Fluxes
  • Atmospheric Soundings
  • Aerosols
  • NOAA High Resolution Doppler LIDAR
  • TOGA Radar
  • Ocean Optics
  • Ocean Mixing

My primary role on this cruise is to work with the Ocean Mixing group led by Dr. Jim Moum from Oregon State University. The Ocean Mixing Group is responsible for sonar measurements of ocean current profiles, high frequency measurement of acoustic backscatter, turbulence/CTD profiling instruments and near surface CTD (Conductivity, Temperature, Depth) measurements. I will be working with other scientific groups as needed and have organized my Teacher at Sea blog to report on daily activities by science group.

Sampling Activities

We have been cruising for a couple of days to the sampling station in the eastern Indian Ocean and are still within the Exclusive Economic Zones (EEZ) of Thailand, India, and other countries.  Here is an interesting fact that I learned about the EEZ – it not only applies to resources, but also applies to data collection.  What this means to the R/V Revelle, is that the scientists cannot collect data until the ship clears the 200 nautical mile EEZ for the counties.  After clearing the EEZ, the science groups can begin data collection.

Atmospheric Soundings

Data collection began on the ship on November 8 and one of the first groups I observed was the Atmospheric Soundings group.  This group is responsible for launching radiosondes using helium balloons (weather balloons).  A radiosonde is an instrument that contains sensors to measure temperature, humidity, pressure, wind speed, and wind direction. Although the balloons can hold up to 200 cubic feet of helium, on this cruise, each balloon is filled with 30-35 cubic feet of helium.   As the radiosonde ascends, it transmits data to the ship for up to 1 ½ hours before the weather balloon bursts and falls into the ocean.  The weather balloons have been reaching an average altitude of 16 km before bursting. Approximately 260 weather balloons will be launched during Leg 3 of the cruise.

The Radiosonde

Watch the video clip below to watch the deployment of a weather balloon.

Computer screen shot of radiosonde data. Temperature is red, relative humidity in blue, wind speed is in green and wind direction is purple.

Ocean Mixing

The Ocean Mixing group began the deployment of XBTs (Expendable bathythermographs) on November 10, 2011. XBTs are torpedo shaped instruments which are lowered through the ocean to obtain temperature data. The XBT is attached to a handheld instrument for launching by a copper wire. Electronic readings are sent to the ship as the XBT descends in the ocean. When the XBT reaches 1,000 meters, the copper line is broken and the XBT is released and falls to the bottom on the ocean.


First step in getting the XBT ready.

Here I am getting ready to launch the XBT.

Launching the XBT

Computer screen shot of thermocline (change in temperature with depth) obtained from XBT instrument. The green shaded curve displays the historical record for comparison.


Personal Log

I arrived in Phuket, Thailand on November 3, 2011 after a 19-hour plane ride.  After dinner and a good night’s sleep, I went to the ship to get acquainted with my new home for the next 6 weeks.  Select the link below for a tour of the R/V Revelle.


Aboard the R/V Revelle in Phuket, Thailand

The Revelle sailed from Phuket on November 6.  As the ship sailed to station, I captured the beauty of the Indian Ocean.


A beautiful day on the Indian Ocean.

Robert Oddo, July 14, 2009

NOAA Teacher at Sea
Robert Oddo
Onboard NOAA Ship Ronald H. Brown 
July 11 – August 10, 2009 

Mission: PIRATA (Prediction and Research Moored Array in the Atlantic)
Geographical area of cruise: Tropical Atlantic
Date: July 14, 2009

Deploying a radiosonde

Deploying a radiosonde

Weather Data from the Bridge 
Outside Temperature 26.01oC
Relative Humidity 89.26
Sea Surface Temperature 28.3oC
Barometric Pressure 1015.9 inches
Latitude 8o 53.96 N Longitude 48o 05.43 W

Science and Technology Log 

We released our first radiosonde this morning.  These balloons have instruments attached to them that will measure atmospheric pressure, temperature and relative humidity as they go up into the atmosphere.  As the balloon rises, it expands as the atmospheric pressure outside the balloon decreases. After about 2 hours the balloon bursts and falls back into the ocean. Four of this particular type of radiosonde will be released every day.  This data is used as input for weather prediction models, weather and climate change research, input for air pollution models and ground truth for satellite data.

Radiosonde is off!

Radiosonde is off!

We also deployed our first global drifter this afternoon. A surface drifter consists of a buoy and a sea anchor. The drifters have sensors that can measure sea surface temperature and the ocean current.  Information is collected by the sensors and uploaded to a passing satellite and then transmitted back to Earth where all the information from all the drifters give us a better picture of what is happening out in the ocean. Drifters are deployed from hurricane hunter aircraft so we can better predict and understand hurricanes. Data from drifters was used to determine where floating debris would be found shortly after the disappearance of Air France flight 447 on May 31, 2009.  For more information on the NOAA Global Drifter Program, visit their website.  

Personal Log 

The drifter buoy is deployed.

The drifter buoy is deployed.

I have received a couple of emails asking about the food on the ship.  We have three meals a day and there is quite a selection. For breakfast, you can have pancakes, eggs, sausage, oatmeal, fresh fruit or a selection of dry cereal.  For lunch, it really varies; today there was a salad, hot dogs, hamburgers and french fries.  Dinner also varies, but so far we have had fish, ribs, chicken and a salad. There is also a veggie option for each meal.  Coffee, tea and other beverages as well as some snack items are pretty much available 24 hours.

Our dining hall

Our dining hall

Tracking the cruise plan

Tracking the cruise plan

Dave Grant, November 11, 2008

NOAA Teacher at Sea
Dave Grant
Onboard NOAA Ship Ronald H. Brown
November 6 – December 3, 2008

MissionVOCALS, an international field experiment designed to better understand the physical and chemical processes of oceanic climate systems
Geographical area of cruise: Southeast Pacific
Date: November 11, 2008

Pilot boat alongside the Brown

Pilot boat alongside the Brown

Science and Technology Log 

The ship was cheered, the harbor cleared, Merrily did we drop, Below the kirk, below the hill, Below the lighthouse top – Coleridge

Finally, it is time to cast off. For days the scuttlebutt has kept us guessing about what has been holding up the cruise. It is approaching Midnight and dock workers have suddenly arrived, crew is adjusting lines and has flushed the birds, and new sounds and rumbling from the engine room are emanating through the deck. I am half asleep, lying in my bunk, and starting to hear announcements from the bridge that remind me of HAIKU:  All stations report. Testing bow thrusters. Visitors must leave the ship. Cast off lines. 

The Ron Brown has come to life! Leaving port is complicated since even the most experienced captain is usually in strange waters. For this reason, a local ship’s pilot is taken onboard to guide us. Thoreau wrote about the pilots off of Cape Cod in the 1800’s and describes how after lookouts spotted a vessel, pilots would race their sailboats to claim the fee for guiding the ship safely to port. Our pilot boarded with great fanfare and salutations from the deck hands. Even though it was calm, it can be dangerous transferring between vessels. Once aboard, he headed to the bridge to take over the wheel.

Close up of the radiosonde

Close up of the radiosonde

Hands-on training started immediately. Our first task was to use a sonde to take radio soundings of the atmosphere above the ship. Radiosondes are lifted by balloons and as they rise, broadcast atmospheric pressure, temperature and humidity data to the ground station. (In this case the lab on the ship.)  This allows atmospheric scientists to record a slice of the air up through the cloud levels through most of the troposphere, where our weather is generated. Radiosondes can also be modified to conduct ozone and radioactivity soundings for pollution studies, but the emphasis of the VOCALS research is the marine layer and its interaction (linkage) between the ocean and atmosphere. Here in the Southeast Pacific, away from continents and major cities, the air should be some of the least polluted on the planet.

Radar reflectors and parachute accessories are available too, but not needed out here since recovery is not an option. Once the balloon reaches low enough air pressure, it expands too much and bursts, and the unit falls into the ocean. (Now, before you start worrying about sea turtles swallowing balloons and meteorologists littering the ocean…this was my first question, and I was told that these materials deteriorate rapidly once they are removed from the hermetically sealed foil containers.)

Many students will state that observing weather and collecting data was the “hook” that got them interested in science; and that certainly applies to me too. As an elementary student helping Mr. Giffin and Mr. “Z” set up mercury column barometers, and seeing 16mm movies of “real scientists” launching weather balloons, really piqued my curiosity. And here I am, so many years later, sending up my own balloons – and for that matter, launching them off a ship in the middle of the ocean!

The science of radiosondes has been around since before WWII and is fairly straight forward. First, read the SAFETY INSTRUCTIONS FOR BALLOON OPERATORS:

  • Do not use in an area with power lines or overhead obstructions.
  • Do not use without consultation and cooperation with aviation authorities. (We will not see any air traffic here, except the scheduled flyovers from VOCALS research aircraft.)
  • Use extreme caution if generating hydrogen gas. (No problem. We use helium; but I did have a flashback of our grandmother Hinemon’s tale about witnessing the Hindenburg explosion from the family farm near Lakehurst, NJ.)
  • The balloon film is only 0.05 mm thick upon launch, so ensure that there are no sharp or pointed objects nearby. (That seems pretty obvious now, doesn’t it Homer Simpson?)
  • And finally, the Dennis the Menace clause: It is not advisable to deflate the balloon if it is leaking. Instead, release the balloon without a load. 
Balloon with message that says, “Thanks TAS!”

Balloon with message that says, “Thanks TAS!”

The units we send aloft are made in Sweden and have a small GPS omni-directional receiving antenna that looks like an eggbeater; a 9-inch wire broadcast antenna; and a thin metal sensor “boom” for temperature and humidity. Power is supplied by a curious little low voltage battery that is activated when soaked in water for a few minutes while the sonde is calibrated by the radio receiver and computer. There are a dozen steps to remember for a successful flight.  First the unit is unpacked from its shipping container. Then it is checked to confirm it is functioning and calibrated to the local conditions of temperature, pressure and humidity; as well as the current latitude and longitude. Fortunately the ship monitors these conditions continuously, so you just have to punch in the numbers prior to release. There is a science to filling the balloons. Too much Helium and it rises too fast for the sensors to record good information. Too little Helium and it may hit the water and malfunction. (You don’t get any second chances!)

Once the balloon is filled, and any messages you wish to photograph are attached to it, clearance is requested from the bridge by letting the duty officer know you will be on the “lee side of the stern” to launch it. Just like when you are seasick…this keeps things blowing away from the boat, instead of in your face. I thought I was clever putting our college logo and president’s name on one, until I saw the Great Pumpkin – a well-decorated balloon that made it to a whopping 23,464 meters on Halloween! (Not to be outdone next time, I am working secretly at night on a Thanksgiving turkey design.) The wind has been remarkably gentle most days, but with the ship rocking and steaming ahead constantly, handling a large balloon while zigzagging across deck between equipment and storage boxes can be challenging, especially in the dark. Sounding balloons are sent up every four hours, so the work is shared by everyone. There is a friendly competition to see whose makes it the highest and gets the best data.

Data from the sounding balloon

Data from the sounding balloon

Note the details in the above image of data from a sounding balloon.  Air PRESSURE (Green line) decreases to 25.7 hPa and the balloon finally bursts. The unit then plunges back to the ocean and pressure increases back to “normal” sea level values. HUMIDITY (Blue line) shows three (3) peaks (About 95%, 75%, and 15%. The highest humidity is at sea level and when the sensor reaches cloud level. The next sharp peak is moisture moving south from the ITCZ (Meteorological Equator).  The small, wide peak is probably Cirrus clouds that were seen earlier before the lower Stratus clouds moved in to block our view. TEMPERATURE (Red line) decreases with height and humidity until the sonde reaches the Tropopause, then begins to rise where higher intensity UV light adds heat. At the top of the image, all three lines merge as the sonde plunges back to sea level.

From the flow of data while this remarkable little instrument is aloft, we can study the decreases in temperature and pressure, and the changes in humidity from sea level to the moment the balloon reaches the bottom of the clouds. An hour or two later, the computer screen even shows the poignant moment (For the launch person, at least), and the decent rate when the balloon bursts and falls back to Earth.

Directional data of balloon winds: Tracking of the sonde shows the direction is drifting in relation to the ship.

Tracking of the sonde shows drifting in relation to the ship.

GPS tracking of the sonde is accomplished with at least four ($) satellites

GPS tracking of the sonde is accomplished with at least four ($) satellites

I’ve looked at clouds from both sides now, From up and down and still somehow, It’s cloud’s illusions I recall, I really don’t know clouds at all.  – Joni Mitchell

A sunset launch

A sunset launch

Personal Log 

I have the best cabin on the ship! Below us is the freshwater tank – the Brown produces over 4,000 gallons of freshwater every day (About 30% more than is needed)  and the sloshing of all that water each time we rock not only drowns out the noise of the ship, but it sounds to me like I’m right on the surface of the water. Falling asleep, I dream that I’m Thor Heyerdahl on Kon-Tiki!

As soon as we hit the open sea you could see some people getting uncomfortable, but as always, “Doc” was on top of it dispensing sea-sickness tablets and in a very few cases, injections. Within a day everyone was moving about and within two days even the dizziest landlubber was up for duty and at every meal. There are few things worse than mal de mer. In part because, as the fishermen like to say, you can’t buy the boat from the captain once you are out there. Years ago on a long and stormy cruise to Madiera, I was issued an experimental device that was part of a NASA trial to treat motion sickness. It was a CD player with headphones that were flat plates fitted behind your ears, which sent out random vibrations to “reset” your middle ear. It reminded me of one of those hearing tests you got in grade school, and seemed to help. However, when I quizzed the ship’s surgeon Dr. Bob (Ex-marine, Vietnam-era Army helicopter pilot, emergency room specialist; trainee in NASA’s early space program, humanitarian and great storyteller) about how his gadget works, he only shrugged his shoulders and replied, “We haven’t a clue.”

An unbelievable sunset

An unbelievable sunset

As it turns out, even NASA doesn’t understand why 80% of us get motion sickness at some point in our lives; but current research is pointing away from the traditional disoriented “middle ear” hypothesis. Over the years I have had success with my own remedies, including: acupressure, ginger cubes, Coca-Cola (Not a commercial endorsement) and as a last resort, over-the-counter remedies with Meclizine. They seem to do the trick, but this night as we sail west to Point Alpha, all I needed to put myself to sleep was Richard Rodger’s soothing tango from the US Navy’s classic WWII Victory At Sea documentary – Beneath the Southern Cross.

“The sea language is not soon learned, much less understood, being only proper to him that has served his apprenticeship.” (Sir William Monson’s “Naval Tracts”)

Words to check today: 

Screen shot 2013-05-18 at 8.09.18 AM

Source information 

From Dave Grant’s collection of stories:

The world’s worst tale of seasickness? As told by Ulysses S. Grant in his Memoirs 

One amusing circumstance occurred while we were lying at anchor in Panama Bay. 

In the regiment there was a Lieutenant Slaughter who was very liable to seasickness. It almost made him sick to see the wave of a table-cloth when the servants were spreading it. 

Soon after his graduation [from West Point] Slaughter was ordered to California and took passage by a sailing vessel going around Cape Horn. The vessel was seven months making the voyage, and Slaughter was sick every moment of the time, never more so than while lying at anchor after reaching his place of destination. 

On landing in California he found orders that had come by way of the Isthmus [Panama], notifying him of a mistake in his assignment; he should have been ordered to the northern lakes. 

He started back by the Isthmus route and was sick all the way. But when he arrived back East he was again ordered to California, this time definitely, and at this date was making his third trip. He was sick as ever, and had been so for more than a month while lying at anchor in the bay. 

I remember him well, seated with his elbows on the table in front of him, his chin between his hands, and looking the picture of despair. 

At last he broke out, “I wish I had taken my father’s advice; he wanted me to go into the navy; if I had done so, I should not have had to go to sea so much.” 

Poor Slaughter! It was his last sea voyage. He was killed by Indians in Oregon. 


Brett Hoyt, October 19, 2006

NOAA Teacher at Sea
Brett Hoyt
Onboard NOAA Ship Ronald H. Brown
October 8 – 28, 2006

Mission: Recovery and maintenance of buoy moorings
Geographical Area: Southeast Pacific, off the coast of Chile
Date: October 19, 2006

Dan Wolfe, senior scientist at NOAA, at his workstation on board the research vessel the RONALD H. BROWN.

Dan Wolfe, senior scientist at NOAA, at his workstation on board

Weather from Bridge 
Visibility:  12nm(nautical miles)
Wind direction:  130º
Wind speed:  20 knots
Sea wave height: 5-7ft
Swell wave height: 3-4 ft
Sea level pressure: 1020.4 millibars
Sea temperature:  19.4ºC or 66 ºF
Air temperature:  19.2ºC or 66ºF
Cloud type: cumulus, stratocumulus

The Scientists 

Today we will be interviewing Dan Wolfe, a senior meteorologist for the National Oceanic and Atmospheric Administration—NOAA for short.  Standing an imposing 6’3”, it seemed only fitting that our next scientist should be studying the heavens.  Mr. Wolfe is a 30-year veteran of NOAA and has been a scientist for the past 31 years.  Mr. Wolfe entered the Coast Guard in 1969 immediately after graduating high school.  He was initially assigned to the Coast Guard icebreaker “Glacier” transferring to the oceanographic unit where he staged scientific experiments.  He traveled to the Arctic and it was there that he discovered his soon to be life long passion for the atmosphere and all that is in it. Mr. Wolfe was a trained scuba diver while stationed on the Glacier. After leaving the Coast Guard he attended Metropolitan State College where he earned his degree in meteorology.  He has the distinction of being the first student to graduate in meteorology at this college.  It was while at Metropolitan College that Mr. Wolfe became a coop student working for NOAA. After earning his degree he went to work for NOAA as a meteorologist where for the next 30 years he has become one if its leading atmospheric scientists.  After seven years on the job he decided that he wanted to know more and enrolled at Colorado State University where he earned his masters degree.

This is a radiosonde, which measures relative humidity, temperature, barometric pressure, and winds as it passes through the atmosphere and radios its data back to the scientist.

This is a radiosonde, which measures relative humidity, temperature, barometric pressure, and winds as it passes through the atmosphere and radios its data back

Mr. Wolfe is one of the few individuals who has worked in BOTH the Arctic (North) and the Antarctic (South) (not just Antarctica but actually at the South Pole). His work has taken him to the depths of the Grand Canyon and to the Arctic more times than he cares to remember.

One of his more exciting job assignments with NOAA is managing a 1,000-ft research tower just off of I25 north of Denver Co.  When I asked Mr. Wolfe what message he would like to give to upcoming scientists he replied, “Kids should seek out paid/or unpaid internships while in high school. Look for internships within your community in careers that you think you might like.  This gives you the opportunity to try a job before investing money and time in college in a future you may not enjoy. If you try a job and discover you don’t like it, try something else until you find something you do like.  Be sure to give the job a chance though.”

NOAA Teacher at Sea, Mr. Hoyt, releasing a radiosonde off the aft deck

NOAA Teacher at Sea, Mr. Hoyt, releasing a radiosonde

The Machine 

One important scientific instrument used by a meteorologist is the radiosonde (pronounced radio sond). This device measures relative humidity, temperature, barometric pressure, and winds by utilizing the global positioning satellite system.  The radiosonde is battery activated then secured to a large helium balloon.  It is then released where it begins its ascent into the upper atmosphere, measuring humidity, temperature, and pressure sending these data back to the scientist via a digital radio frequency. Depending on the balloon used, these radiosondes can obtain heights in excess of 6 miles. The atmospheric data collected on this cruise will be shared with other scientists to help improve global weather computer models.

The Experiment 

There is no experiment as these data are transmitted via satellite link immediately after the flight is finished to the National Center for Environmental Prediction to be fed into their continuously running forecast models.

Classroom Activities 

Elememtary K-6: 

Ask the students, “What is weather?”  “Why is it important to predict the weather?” Have the students take a piece of drawing paper and divide it into four equal parts.  In each part have the students draw and color four different types of weather common to where they live.  Example could be sunny, rainy, partly cloudy, and snow.

Middle School:  

Why do we use calibrated thermometers to measure air temperature?   Ask students to answer on paper whether the classroom is hot, warm, cool, or cold and to estimate the actual temperature of the room.  Then compare the students’ answers to the actual temperature.  Then discuss the importance of a “standard.”  Without this “standard” scientists around the world would have no way of communicating what the atmosphere is doing.

Please examine the High School for more activities

High School: 

Everyday we hear on the radio, television, or newspaper that it will be sunny, partly cloudy, partly sunny, etc.  How do meteorologist arrive at this? Today we will learn how.

Divide the sky into eight parts.  Examine each part and count how many squares have clouds. There is no hard and fast rule on what to do with partially filled boxes

No squares having clouds-Clear or Sunny 

One to two squares having clouds-Mostly Clear or Mostly Sunny 

Three or four squares having clouds-Partly Cloudy or Partly Sunny 

Five, Six, or Seven squares having clouds-Mostly Cloudy 

Eight squares having clouds-Overcast or Cloudy Take the sky photo below and print it out. Draw a grid like the one above on top of the sky photo. Have the students write down what they think the day is.  Then compare the student’s answers. Is this an exact science?

Have your teacher take photos of the weather in your area and do your own.


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.

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.

Eric Heltzel, October 9, 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 9, 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 

After Dr. Lundquist and I have a successful radiosonde launch we return to the computer terminal and watch the measurement data come in.  My favorite display is a color-coded graph showing temperature, dew point, and relative humidity graphed against the altitude of the radiosonde. The main area of study is taking place where we are in the eastern Pacific off the coast of northern Chile.  In this area there is a large, semi-permanent layer of stratus clouds.  The effects these clouds have on the ocean temperature, and vice versa, is one of the reasons for choosing this area to study.

As the balloon ascends from the ship the temperature cools at the dry adiabatic rate. The dew point goes down but not as rapidly.  Usually at an elevation of about  600 meters the dew point and temperature intersect.  On the same screen green line showing relative humidity hits 100% as we would expect.  This marks the base of the cloud layer.

As the radiosonde ascends another 200 to 400 meters the temperature shoots way up, as much as 8 degrees C.  This indicates the top on the cloud layer where the sun is shining brightly. As the balloon continues to ascend the temperature once again cools consistently at the dry adiabatic rate.  It’s about negative forty degrees C at an altitude of 20 kilometers.  In this part of the atmosphere the relative humidity approaches zero and the dew point stays well below the air temperature.  This suggests the upper air is descending and is stable. The bottom 800 meters is referred to as a marine boundary layer.

Despite the constant cloud cover there is very little precipitation in this area.  Temperatures at the ocean level are surprisingly cool as evidenced my most of the crew wearing long pants and jackets or sweatshirts.  Atmospheric and oceanic data in this area are very sparse. One goal of the Stratus Project is to gather more information so we can better understand the interrelationships between ocean and atmosphere.

Personal log

As I write this I am on my watch in the main science lab.  I’m preparing to launch a Drifter in about 15 minutes and I will launch a weather balloon at 13:00.  It’s really fun to throw things into the ocean and release balloons into the atmosphere and see where they go.

Our ETA at the Stratus mooring site is 17:30.  We are approaching the end of southerly leg of our cruise. There are about six days of work scheduled at the buoy site.  It should be interesting.