Jacquelyn Hams: 3 December 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: December 3, 2011

Weather Data from the R/V Revelle Meteorological Stations

Time: 0930
Wind Direction: 232.10
Wind Speed (m/s): 3.4
Air Temperature (C): 27.7
Relative Humidity: 77%
Dew Point: (C): 23.7
Precipitation (mm): 42.2

PAR (Photosynthetically Active Radiation (microeinsteins): 1942.5

Long Wave Radiation (w/m2): 409.3
Short Wave Radiation (w/m2): 373.1

Surface Water Temperature (C): 28.70
Sound Velocity: 1541.5
Salinity (ppm): 33.7
Fluorometer (micrograms/l): 0.3
Dissolved Oxygen (mg/l): 2.4
Water Depth (m): 4422

Wave Data from WAMOS Xband radar

Wave Height (m) 0.5
Wave Period (s): 7.4
Wavelength (m): 86
Wave Direction: 1140

Science and Technology Log

Surface Fluxes Group

The Surface Fluxes group consists of James Edson, University of Connecticut, Ludovic Bariteau, University of Colorado Cooperative Institute for Research in Environmental Sciences (CIRES), and June Marion, Oregon State University. This group measures the amount of radiation and heat into and out of the ocean and was covered in the November 12, 2011 blog posting.

The purpose of this posting is to highlight the work of Ludovic Bariteau who is measuring the carbon dioxide flux between the atmosphere and ocean. For redundancy and testing, the carbon dioxide in the atmosphere is measured with several infrared instruments pictured below. Two of the instruments are in the pilot stage and were developed for this research cruise. The equipment used for measuring carbon dioxide in seawater is done in collaboration with Wade McGillis from Lamont-Doherty-Earth Observatory (LDEO). Ludovic plans to refine the instrumentation based on the pilot test. The carbon dioxide data will be correlated with surface flux data to present a complete picture of ocean atmosphere fluxes.

Photograph of flux instruments.

Photograph of flux instruments on the mast. The instruments measuring air CO2 are indicated by the black arrows. Image credit: James Edson.

Ludovic Bariteau in front of instrument to measure carbon dioxide fluxes.

Ludovic Bariteau in front of the specialized instrument to measure carbon dioxide fluxes between the ocean and atmosphere.

Closeup of carbon dioxide flux instrument.

The above photograph is a close-up of the apparatus used to measure the carbon dioxide content in the ocean water.

Ludovic Bariteau pointing to CO2 measurement device.

Photograph of Ludovic Bariteau pointing to one of the air CO2 measurement devices in the pilot stage.

        

Data printout of Carbon dioxide values of air and water measured from instrumentation aboard the Revelle provided courtesy of Ludovic Bariteau

Data printout of Carbon dioxide values of air and water measured from instrumentation aboard the Revelle provided courtesy of Ludovic Bariteau

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What about the MJO?

Previous postings described the work being done by the 7 science groups and the instrumentation being used to measure the various characteristics of the ocean-atmosphere interaction that may be part of the active phase of the MJO. Readers of this blog may be asking the same question that some of my students are now asking, “Did you experience the MJO?”

Data collected to date by the science groups suggests that we experienced an active MJO phase. Although It will take years to analyze and correlate the data collected from the various organizations involved in Project DYNAMO, the Revelle experienced high winds, colder surface water surface temperatures, and the intermittent storms separated by quiescent periods that are believed to accompany the active phase of the MJO. Based on initial data this active phase may have occurred between the approximate dates of Nov. 24 through Dec.2.

Wyrtki Jet Current

Before discussing the effects of the MJO on Indian Ocean circulation, it is useful to provide a brief background on the currents in the Indian Ocean which are more complicated than those in the Atlantic and Pacific Oceans in several ways:

  • Indian Ocean currents are poorly defined
  • They are influenced by the presence of the Eurasian continent
  • They are more variable than the Atlantic or Pacific Ocean currents. Some Indian Ocean currents vary with the seasons. For example, on the top diagram below, notice there are two unnamed gyres located in the northern hemisphere west and east of India.

Diagram of Indian Ocean Currents

The Revelle left station on December 2, and began north south transects across the equator to delineate the extent and the speed of the Wyrtki Jet Current. The Wyrtki Jet is a narrow jet-like surface current that flows eastward during the transition periods between the Northeast and Southwest Monsoon currents and is believed to accompany the active phase of the MJO.

A summary of the monsoon system in the Indian Ocean taken from the pdf version of Regional Oceanography: An Introduction by Tomczak and Godfrey. The Wyrtki Jet may be the Equatorial Jet identified on the below diagram.

Wyrtki jet speeds of 150 cm/s eastward at the surface were identified during the cruise.  In addition a current flowing westward was identified at a depth of 100 m. The purpose of the transects is to delineate the lateral and vertical extents of these currents.  The currents are measured using four Acoustic Doppler Current Profiler (ADCPs) located in the hull of the ship (these are Doppler sonars, analogous to Doppler radar and lidar measurements discussed in previous blogs).

Personal Log

I worked the winch for the last drop of Chameleon on Leg 3 of Project DYNAMO aboard the R/V Revelle.  I must say that I am proud of my work as a “Winch Winder”.  In the past 5 weeks, I experienced a range of emotions regarding the winch.  I initially felt fearful of working solo on such a valuable instrument. Once I began working solo, I was still intimidated because the winds and currents are so variable at the equator. Intimidation was finally replaced by competence after operating the instrument in 40 knot winds without slamming it into the ship! Aurelie Moulin was kind enough to shoot this video of me just before Chameleon was pulled out of the water on the last drop.

I would like to share my interview with Jude Irza, Ordinary Seaman aboard the R/V Revelle who provides extremely thoughtful advice and insight regarding career choices and preparation that may be helpful not only for students unsure of their future, but for those who may desire a career change at any stage in life.

Photograph of Jude Irza

Question: What made you decide on a career in this field?

 That question is straight forward enough but my answer is a little bit convoluted.  I never woke up one day and decided that I wanted to become a Merchant Marine and work on Oceanographic Ships.  In fact, I have been fortunate to have had two careers before this one:  Naval Officer and Finance Manager.  Here’s how I embarked on my first two careers.

 First, I attended college on a Naval Reserve Officers’ Training Corps Scholarship.  After college, I went to Flight School in Pensacola, Florida, and flew as a navigator in the United States Navy.  While in the Navy, I decided to expand my horizons and earn a Masters in Business Administration. While completing my MBA, I decided that a career in finance would be challenging and rewarding.  So I resigned my commission and I worked at a large telecom company in San Diego.  Later, I had the opportunity to join a telecom start-up and later a consulting company.   Although I enjoyed working in finance for fifteen years, I was ready to do something exciting and different.  I had always thought working as an Officer in the Merchant Marine would be fun. Expecting to be too old for this career, I was surprised and pleased when my research uncovered a new program where I could go to sea and work towards a Third Mate License through a two-year program offered by the Pacific Maritime Institute (PMI) in Seattle, Washington.  So, approximately two years ago, I joined the program and was partnered with the Scripps Institute of Oceanography.  I joined the R/V Revelle as an Ordinary Seaman.  Already, this is my fourth trip on the R/V Revelle and I am close to finishing PMI’s program.  I hope to take my Coast Guard License exams next summer and have my 1600 ton 3rd Mate License shortly thereafter.

 Question:  What are the positives and negatives of this line of work?

 The exact nature of the work depends on what billet or position one is filling and to an extent that determines the positives and negatives.  For example, an Ordinary Seaman like me spends most of the time cleaning, removing rust and painting.  Work is performed both inside and outside of the ship.  Mates, however, are Merchant Marine Officers, and spend most of their time standing watch, on the bridge of the ship.  Most, if not all, merchant mariners would agree that being able to travel and see the world are positives in this line of work.  The biggest negative is separation from family members for months at a time.  Typically, at Scripps, we are out to sea for eight months out of twelve.  Moreover, especially at the lower level positions, the work can be arduous and sometimes monotonous.

 Question:  What advice would you give students who are unsure of their career goals?

 I would give students five pieces of advice:

1. Get Information and Prerequisites – Get on the internet and research the careers in which you might be interested.  Learn about what qualifications and prerequisites are necessary for each career.  Try to find a person who is in that career and ask them good questions.  Be realistic, but also look for unconventional pathways.

 2. Inventory your Skills and Abilities – Try to determine what you enjoy doing and what you are good at.  Try and see what careers other people chose that have your talents and abilities.

 3. Get Real-World Experience – Try and experience careers directly without investing too much time and energy by taking a part-time, internship or volunteer position.  You’ll learn an enormous amount by working alongside other people.

 4.  Change your Career if you find that it is not Right for You – Some people, including myself, are not suited to only one career.  Don’t be afraid to try something new if you no longer find enjoyment in your current line of work.  But be financially responsible and try to not incur too much debt especially in your younger years.  You want to keep your options open and debt can limit options.

 5.  You are Never Too Old to Start Again – I am forty-five years old, but feel energized doing something new.  I don’t know if I will be in this career ten years from now, but I am certainly enjoying it now.

Jacquelyn Hams: 25 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 25, 2011

Weather Data from the R/V Revelle Meteorological Stations

Time: 0830
Wind Direction: 2340
Wind Speed (m/s): 9.6
Air Temperature (C): 25.5
Relative Humidity: 90.6%
Dew Point: (C): 24.3
Precipitation (mm): 41.3

Long Wave Radiation (w/m2): 442.5
Short Wave Radiation (w/m2): 114.6

Surface Water Temperature (C): 29.60
Sound Velocity: 1544.9
Salinity (ppm): 35.3
Fluorometer (micrograms/l): 0.3
Dissolved Oxygen (mg/l): 2.5
Water Depth (m): 4637

Wave Data from WAMOS Xband radar

Wave Height (m) 2.1
Wave Period (s): 8.9
Wavelength (m): 123
Wave Direction: 2780

Science and Technology Log

NASA TOGA C-Band Doppler Radar Group

The TOGA (Tropical Ocean Global Atmosphere) Radar Group consists of Michael Watson, NASA Contractor from Computer Science Corporation, Goddard Space Flight Center, Wallops Flight Facility, Wallops Island, Virginia; Elizabeth Thompson, Colorado State University; and Owen Shieh of the University of Hawaii.

The following paragraphs provide a brief description of TOGA C-Band Doppler Radar.

Radar is an acronym for radio detection and ranging. Radar was developed just before World War II for military use but now serves a variety of purposes including weather forecasting. Radar is an electronic device which transmits an electromagnetic signal, receives back an echo from the target and determines various characteristics of the target from the received signal. Doppler radar adds the capability of measuring direction and speed of a target by measuring the Doppler Effect, or the component of the wind going either toward or away from the radar.

  • Doppler radar is divided into different categories or bands, according to the wavelength of the radar.  Some common Doppler bands are:
  •  S-band radars operate on a wavelength of 8-15 cm and are useful for far range weather observation.
  •  C-band radars operate on a wavelength of 4-8 cm and are best suited for short-range weather observation.
  •  X-band radars operate on a wavelength of 2.5-4 cm and are useful for detecting tiny precipitation particles

The NASA TOGA C-Band radar has a range of 300 km. In addition to the TOGA C-band radar, the ship has both S and X band radar. These three systems allow large and small-scale forecasting capabilities.

When not deployed on field campaigns, TOGA radar resides at Goddard Space Flight Center, Wallops Flight Facility, Wallops Island, Virginia, where it gathers meteorological data and supports launches.

The large dome in the center houses the NASA Doppler C-Band radar antennae. Image credit: Jacquelyn Hams

The large dome in the center houses the NASA Doppler C-Band radar antennae. Image credit: Jacquelyn Hams

During Leg 3 of Project DYNAMO, TOGA radar scans are performed in the following intervals:

Automated high-resolution scans for a 150 km radius every 10 minutes

  • Automated high-resolution scans for a 300 km radius at the top and bottom of the hour (every 59 and 29 minutes)
  • Vertical cross sections at 9,19,39 and 49 minutes past the hour.

 Below are examples of radar scan images of a single storm cell and rainfall provided courtesy of Owen Shieh.

The TOGA Radar image on the left is a horizontal image looking down on the rain.  The ship is in the center. North is straight up toward the top of the image. The radar range is 150 km. The arrow indicates a single storm cell that is located 40 km from the ship. Towards the east (right side of the diagram) are large areas of light rain, indicated by white arrows.  Radar image on the right is a vertical cross section through the storm cell (indicated by the black arrow). The top of the storm extends up to 5 km and contains moderate rain indicated by the yellow color.

The TOGA Radar image on the left is a horizontal image looking down on the rain. The ship is in the center. North is straight up toward the top of the image. The radar range is 150 km. The arrow indicates a single storm cell that is located 40 km from the ship. Towards the east (right side of the diagram) are large areas of light rain, indicated by white arrows. Radar image on the right is a vertical cross-section through the storm cell (indicated by the black arrow). The top of the storm extends up to 5 km and contains moderate rain indicated by the yellow color.

TOGA Radar image on the left is the same as above, except taken 10 minutes later.  Notice that the storm cell (indicated by the black arrow) is closer to the ship, approximately 37 km away.

TOGA Radar image on the left is the same as above, except taken 10 minutes later. Notice that the storm cell (indicated by the black arrow) is closer to the ship, approximately 37 km away.

The TOGA radar image above is taken from a range of 300 km.  These images are taken every 30 minutes.  There are four areas of light to moderate rain surrounding the ship (indicated by white arrows).  Notice the scale of the storm cell (indicated by black arrow) looks considerably smaller. The large scale TOGA Radar image allows a wider view of the aerial distribution of rain.

The TOGA radar image above is taken from a range of 300 km. These images are taken every 30 minutes. There are four areas of light to moderate rain surrounding the ship (indicated by white arrows). Notice the scale of the storm cell (indicated by black arrow) looks considerably smaller. The large-scale TOGA Radar image allows a wider view of the aerial distribution of rain.

Personal Log

The day after Thanksgiving, the Ocean Mixing Group decided to pull the T Chain out of the water after discovering a couple of damaged cables. The Chief Scientist ultimately decided to move the ship to another location on the other side of the buoy. It was extremely windy that day and the team was trying to perform this task in hard hats which constantly blew off in the wind. I am sure we looked extremely comical to those who were watching. In addition, we had to juggle large pieces of foam used to protect the T Chain which promptly blew away. There were at least seven of us and I thought we probably looked like a scene from a Marx Brothers movie.

We are experiencing squalls on almost a daily basis that are separated by quiet calm periods and occasional sunshine. Weather data indicates that we may be in the active phase of the MJO. I managed to get some interesting sunset photographs with the cloud formations.

These photographs were taken at sunset on the Indian Ocean between squalls. Image credits: Jacquelyn Hams

This photograph was taken at sunset on the Indian Ocean between squalls. Image credits: Jacquelyn Hams

This photograph was taken at sunset on the Indian Ocean between squalls. Image credits: Jacquelyn Hams

My students want to know how I am adapting to the lack of privacy. This is not my first time on a ship and I own a sailboat so being at sea is not an uncommon experience for me. However, being at sea this long with so much to accomplish in a short time has caused the lack of privacy to become a big issue for me. In addition to covering the 7 science groups for this blog, I am teaching the last 5 weeks of my classes via distance education and posting assignments for my students based on data obtained on this cruise.

There are little things on the ship that make the lack of privacy more tolerable. There are steak Sundays that include a tasty non-alcoholic ginger beer – a weekly treat. There is also Yoga everyday from 1:00 p.m.to 2:00 p.m. I brought one of my yoga DVDs from home as did others so we have a variety of programs and do not get bored. The standing poses are difficult on a moving ship, but I manage to get through it.

I am beginning to realize that I enjoy my time on the winch with Chameleon because that is the only time I am physically alone. I am thinking to myself how crazy and scary it is that my idea of spending quality alone time involves a noisy sampling instrument! But alas, even Chameleon cannot make up for the fact that I miss my own private bathroom.

One morning while waiting for the sunrise on the bow, I was treated to quite a show of jumping fish. The fish are tuna and are jumping to avoid predators. I have seen jumping fish many times while on the winch, but never so many and for such an extended period of time. They continued their performance until well after breakfast. I shot this video shortly after breakfast.

Jacquelyn Hams: 14 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 14, 2011

Weather Data from the R/V Revelle Meteorological Stations

Time: 1045
Wind Direction: 262.60
Wind Speed (m/s): 135.8
Air Temperature (C): 28
Relative Humidity: 79.7%
Dew Point: (C): 24.20
Precipitation (mm): 42.4

PAR (Photosynthetically Active Radiation) (microeinsteins): 1101.5
Long Wave Radiation (w/m2): 410.3
Short Wave Radiation (w/m2): 192.5

Surface Water Temperature (C): 29.8
Sound Velocity: 1545.1
Salinity (ppm): 34.8
Fluorometer (micrograms/l): 0.2
Dissolved Oxygen (mg/l): 2.8
Water Depth (m): 4637

Wave Data from WAMOS Xband radar

Wave Height (m) 1.3
Wave Period (s): 13.2
Wavelength (m): 236
Wave Direction: 2800

Science and Technology Log

Ocean Mixing

All about CTDs

A CTD is a standard instrument used on ships to measure conductivity, temperature and depth. Three CTD systems are being used during Leg 3 of Project DYNAMO to measure CTD.

  • The Revelle deploys the ship’s CTD twice a day to a depth of 1,000 m. The CTD measurements can be viewed on a monitor in the computer room.
Ship's CTD

Ship's CTD

Ship's CTD in water

Ship's CTD in water

Ship's CTD data display

Ship's CTD data display

Data obtained from the ship's CTD

Data obtained from the ship's CTD

  • The Ocean Mixing group is using a specialized profiling instrument that was designed, constructed, and deployed by the microstructure group at the College of Oceanic and Atmospheric Sciences, Oregon State University. The instrument, called “Chameleon”, measures CTD and turbulence. Chameleon takes continuous readings to a depth of 300 m as it is lowered through the water column. The top of the instrument has brushes to keep the instrument upright in the water and make it hydrodynamically stable so that very precise measurements of turbulence can be achieved. These measurements allow computations of mixing, hence the name Ocean Mixing Group. The instrument freely falls on a slack line to a depth of 300 m after which it is retrieved using a winch. The Chameleon has been taking continuous profiles at the rate of about 150/day since we have been on station and will continue taking measurements for the next 28 days.
Photograph of Chameleon

Photograph of Chameleon

Close-up of Chameleon's sensors

Close-up of Chameleon's sensors

Data obtained from the Chameleon
  • The T Chain CTD aboard the ship was also designed by the microstructure group at the College of Oceanic and Atmospheric Sciences, Oregon State University. This instrument measures CTD in the near-surface (upper 10 m) using bow chain-mounted sensors (7 Seabird microcats + 8 fast thermistors). The T Chain takes data every 3 seconds, and although that is not very fast, the data is extremely accurate (within 1/1000th of a degree – 3/1,000th of a degree). The T Chain is mounted on the bow and has been taking measurements continuously since we have been on station. These measurements focus on the daytime heating of the sea surface and the freshwater pools created by the extreme rainfall we have been observing and which is associated with the MJO.
Photograph of T Chain

Photograph of T Chain

Data obtained from T Chain

Data obtained from T Chain

NOAA High Resolution Doppler LIDAR (Light Detection And Ranging) Group

A Brief Introduction to LIDAR

The following introduction to LIDAR systems was provided by Raul Alvarez.

In LIDAR, a pulse of laser light is transmitted through the atmosphere. As the pulse travels through the atmosphere and encounters various particles in its path, a small part of the light is scattered back toward the receiver which is located next to the transmitter. (You may have seen similar scattering off of dust particles in the air when sunlight or a laser pointer hits them.) The particles in the atmosphere include water droplets or ice crystals in clouds, dust, rain, snow, aircraft, or even the air molecules themselves. The amount of signal collected by the receiver will vary as the pulse moves through the atmosphere and is dependent on the distance to the particles and on the size, type, and number of particles present. By keeping track of the elapsed time from when the pulse was transmitted to when the scattered signal is detected, it is possible to determine the distance to the particles since we know the speed of the light.

Once we know the signal at each distance, it is now possible to determine the distribution of the particles in the atmosphere. By measuring how the light was affected by the particles and the atmosphere between the LIDAR and the particles, it is possible to determine things such as the particle velocity which can yield information about the winds, particle shape which can indicate whether a cloud is made up of water droplets or ice crystals, or the concentration of some atmospheric gases such as water vapor or ozone. The many kinds of LIDARs are used in many different types of atmospheric research including climate studies, weather monitoring and modeling, and pollution studies.

Typical lidar signal as a funciton of range

Typical lidar signal as a function of range

Photograph of Ann and Raul inside the LIDAR van.

Photograph of Ann and Raul inside the LIDAR van.

Raul explains the inner workings of LIDAR aboard the ship. From left to right: 1st photo shows Raul and the LIDAR system; 2nd and 3rd photos display the optical components of the LIDAR; 4th photo is the rotating scanner base.

Raul explains the inner workings of LIDAR aboard the ship. From left to right: 1st photo shows Raul and the LIDAR system; 2nd and 3rd photos display the optical components of the LIDAR; 4th photo is the rotating scanner base.

The four cone-shaped devices are differential GPS antennae used to correct for the motion of the boat.

The four cone-shaped devices are differential GPS antennae used to correct for the motion of the boat.

An integrated motion compensation system is used to stabilize the scanner to maintain pointing accuracy. As you can see from the video below, the scanner maintains its position relative to the horizon while the ship moves.

The slides below represent a Doppler LIDAR data sample from Leg 3 of the Revelle cruise. The images and slides were provided courtesy of Ann Weickmann.

Image credit: Ann Weickmann

Image credit: Ann Weickmann

Image Credit: Ann Weickmann

Image Credit: Ann Weickmann

Image credit: Ann Weickmann

Image credit: Ann Weickmann

Image credit: Ann Weickmann

Image credit: Ann Weickmann

Image credit: Ann Weickmann

Image credit: Ann Weickmann

Personal Log

The R/V Revelle is not a NOAA ship. It is part of the University-National Oceanographic Laboratory System (UNOLS) and part of the Scripps Institution of Oceanography research fleet. A few crew members were kind enough to take time from busy schedules to talk with me about their careers. Students may find these interviews interesting especially if they are exploring career options.

The food aboard the Revelle is very good thanks to our cooks, Mark and Ahsha. They are very friendly crew members and always happy to accommodate the diverse eating schedules of scientists who have to work during meal hours.

Mark Smith, Senior Cook

Mark Smith, Senior Cook

Ahsha Staiger, Cook

Ahsha Staiger, Cook

Meanwhile back on the winch, I am beginning to get the hang of it. I will not say that I am comfortable, because I am always aware that I am in charge of a very expensive piece of equipment. I alternate between operating the winch, operating the computer, standby time (to assist as needed) and free time.

Jackie on the computer in the Hydro lab.

Jackie on the computer in the Hydro lab.

Dramatic cloud formation at sunrise.

Dramatic cloud formation at sunrise.