2011 – Page 2 – NOAA Teacher at Sea Blog

December 9, 2011March 26, 2021

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

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.

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

jackie_ham51 — 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.

December 5, 2011March 26, 2021

Jacquelyn Hams: 24 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 24, 2011

Weather Data from the R/V Revelle Meteorological Stations

Time: 0830
Wind Direction: 246.10
Wind Speed (m/s): 9.3
Air Temperature (C): 27.4
Relative Humidity: 86.1%
Dew Point: (C): 25.1⁰
Precipitation (mm): 25.1

PAR (Photosynthetically Active Radiation) (microeinsteins): 177
Long Wave Radiation (w/m²): 454.3
Short Wave Radiation (w/m²): 36.7

Surface Water Temperature (C): 30⁰
Sound Velocity: 1545.9
Salinity (ppm): 35
Fluorometer (micrograms/l): 0.9
Dissolved Oxygen (mg/l): 2.6
Water Depth (m): 4637

Wave Data from WAMOS Xband radar

Wave Height (m) 2.2
Wave Period (s): 15.3
Wavelength (m): 290
Wave Direction: 2900⁰

Science and Technology Log

Aerosols Group

The Aerosols Group consists of Derek Coffman, Langley Dewitt and Kristen Schultz from the NOAA Pacific Marine Environmental Lab (PMEL) in Seattle, Washington. The Aerosols group measures the chemical, physical, and optical properties of sub and supermicron aerosols (liquids or solids suspended in gas) in the lowest layer of the troposphere. Aerosols are important in the study of climate change and the largest unknown due to the complicated nature of the particles. Aerosols are being studied in the MJO experiment to determine how they affect the radiative balance and how the MJO affects aerosols.

The measurements and analyses include:

real-time and filter-based analysis of the aerosol chemical composition
size distributions from 20 nm to 10 microns (aitken mode to course mode aerosols)
particle number concentrations
aerosol scattering and absorption
cloud condensation nuclei (CCN)
total mass of filtered collected aerosol
O₃ and SO₂ gas phase measurements.

Aerosols are captured via an opening in the inlet (mast). The base of the inlet consists of 21 individual sample lines. The inlet is designed to collect particles in average marine conditions without preferentially selecting particles and is efficient in collecting particles up to 10 microns in diameter. Each sample line connects to a specific instrument for analysis. The captured aerosols are sampled for physical, chemical, and optical properties. . In general, for the ocean, particle sizes that are <1 micron are typically more anthropogenic, while particles >1 micron are sea salts and generated by wind and rain.

Aerosols are captured through the Inlet (mast).

Base of aerosol inlet with sample lines.

Impactors are attached to the sample lines to separate and collect aerosols. Each impactor has a filter to capture a particular particle size range. The filters are removed from the Impactors in a clean lab for analysis. Half of the samples collected are analyzed on the ship and the remaining samples are analyzed at the NOAA PMEL Lab in Seattle, WA. Analytical methods used on the ship to measure chemical species are ion chromatography, liquid chromatography with mass spectrometry (LCMS), total organic carbons (TOC), and organic carbon and elemental carbon (OCEC). The optical properties measured include scattering and absorption. Scattering is measured by an instrument called a nephelometer and absorption is measured by a Particle Soot Absorption Photometer (PSAP). The physical properties measured are total particle concentration and size distribution of the particles. Condensation particle counters (CPCs) measure the particle concentrations and size distribution is measured by a Scanning Mobility Particle Sizer (SMPS), The Aerosol Mass Spectrometer measures the size and chemical composition of non-refractory submicron aerosols.

Vacuum Pump closet houses vacuum and pressure needs for the aerosol vans.

Example of a clean filter (left) and sampled filter containing exhaust from the ship (right).

The Aerosol Mass Spectrometer captures and analyzes the chemical composition of aerosol particles in near real time (every 5 minutes).

Derek in the Aerosol van pictured with various instrumentation.

The diagrams pictured above are based on a model prepared by Derek Coffman. The back trajectories on the left show that sub micron aerosols are dominant in the continental air mass and there is also more organic aerosol that is likely causing the absorption in the continental air mass. The clean marine diagram shows that sub micron aerosol is greatly reduced and aerosols >1 micron (coarse mode) play a dominant role in scattering in the air mass.

Personal Log

Thanksgiving week proved to be the most interesting weather of the cruise. The winds picked up to 48 knots on Thanksgiving Day. This made for a real exciting time on the winch. During several drops (each time Chameleon is lowered in the water column), I had to hold on to the canopy with one hand, and the winch with the other so I would not fall over when the swells hit the stern of the ship.

I was surprised that Chief Scientist Jim Moum continued to work on his computer and did not run out to snatch me away from his valuable research instrument! If he had that much confidence in my ability to handle the situation, I had to prevail. Just as I was convincing myself I had to prevail, I heard the bridge call on the hand-held radio. I could not understand the communication and did not want to release the winch since it was difficult to control in the wind. Someone from the Ocean Mixing Group came out to tell me that the bridge called and could not control the ship direction and to take Chameleon out of the water. By this time Chameleon was trailing behind the ship and I could not see if it had gone under the ship. A bit of chaos ensued and I saw a boat hook out of the corner of my eye as crew prepared to get Chameleon out. Somewhere in the midst of the chaos, Jim Moum came on deck and decided that profiling could continue. By that time the ship had re-positioned, however, the wind speed was the same. Jim surveyed the situation and said that he had profiled in far worse weather conditions and went back to his work. I breathed a huge sigh of relief when my shift was over that night and Chameleon was not damaged.

Thanksgiving Day was another day of collecting data. The cooks prepared a Thanksgiving Dinner and I think I speak for all of the scientists when I say we appreciated the turkey and all the trimmings.

Scott, a Wiper in the Engineering Department asked me if I would like an interesting video of a crew job for the website. Scott is a polite crew member and has an interest in education. My first question was “What is the job description for a wiper?” I was told that a wiper is an unlicensed engine room staff member. According to Scott, he empties trash, cleans, and performs other projects as needed such as needle gunning (removing paint and rust from metal surfaces) natural air vent shafts as seen in the video below. I wasn’t prepared for the noise when I shot this video.

There are no gorgeous sunrise and sunset photographs to end this blog – we are probably in the beginning stages of the MJO. There is a tropical cyclone to our north and the outer bands were reaching the ship. We are experiencing squalls with high winds. It is unusual to have cyclones during the MJO event – they usually develop in the wake of the cycle according to the Atmospheric Soundings Group. I get dressed in rain boots and gear and run to the winch and run back inside when my shift is over. Although I am sure you would like to see a photo, it is not exactly a desirable Kodak moment for cameras. Stay tuned, the weather is bound to change.

For this post’s quiz, please answer in the comments of this post:

Using the Aerosol source diagram above, what particle size aerosols are dominant in
continental air masses and what particle size aerosols are dominant in clean marine air masses?

December 5, 2011March 26, 2021

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.

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.

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.

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.

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.

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.

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.

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.

November 23, 2011March 26, 2021

Jacquelyn Hams: 13 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 13, 2011

Weather Data from the R/V Revelle Meteorological Stations

Time: 810
Wind Direction: 262.40⁰
Wind Speed (m/s): 2.7
Air Temperature (C): 28.1
Relative Humidity: 77.3%
Dew Point: (C): 23.7
Precipitation (mm): 40.2

PAR (Photosynthetically Active Radiation) (microeinsteins): 2092.5
Long Wave Radiation (w/m²): 413.3
Short Wave Radiation (w/m²): 442.7

Surface Water Temperature (C): 29.5⁰
Sound Velocity: 1544.8
Salinity (ppm): 35.2
Fluorometer (micrograms/l): 69.7
Dissolved Oxygen (mg/l): 3.2
Water Depth (m): 4637

Wave Data from WAMOS Xband radar

Wave Height (m) 0.7
Wave Period (s): 8.1
Wavelength (m): 103
Wave Direction: 209⁰

Science and Technology Log

Atmospheric Soundings

In addition to launching radiosondes, the Atmospheric Soundings Group operates a Wind Profiler to observe air mass density directly above the radar. Each beam sends back a return and more returns indicate humid or rainy conditions. The wind profiler operates twenty-four hours a day on the ship. The wind profiling is revolutionary for this cruise in that 8 profiles per day will be performed by three people who are dedicated to this experiment. This detail will allow the scientists to see small scale variations in the atmosphere that have not been seen in the past with fewer profiles.

Wind Profiler displays light winds and little air movement (left). Colors indicate high intensity and fast air movement (right). The image on the right was captured during an episode of rainfall.

Ocean Optics

The Ocean Optics team is led by KG Fairbarn of the Earth Research Institute at the University of California Santa Barbara. KG does three optics casts a day using a Microprofiler. The data can be viewed on the computer in real time as the instrument is lowered through the water column to a depth of 50 meters. The Microprofiler measures the irradiance within the visible light spectrum.

Irradiance is defined as the measure of solar radiation on a surface in watts/m².The amount of irradiance absorbed within the water column is a function of chlorophyll and nutrients. The Microprofiler contains a flourometer to measure chlorophyll and KG obtains the nutrient content from water samples collected from the Revelle CTD.

In terms of Project DYNAMO, KG is measuring light that penetrates a layer of water and heat that penetrates the ocean. This information allows scientists to quantify the heat distribution through the water column and relate it to the flux (transfer or exchange of heat) at the surface and flux at the air-sea interface.

Revelle CTD with Niskin bottles attached for collecting water samples

Personal Log

Life at Sea

What is it like to live aboard a ship that is operating 24/7? There are negatives and positives. It is busy and often noisy. Doors are always closing and opening and the maintenance is constant. Privacy is non-existent. I often get up early and go on the bow to watch the sunrises and sunsets and to get some quiet time. However, I don’t have much time to ponder the negatives of life at sea as I am very busy familiarizing myself with and reporting on all 7 science groups. I work a split watch with the Ocean Mixing Group between 1500 and 2100. In addition, I am creating, posting, and grading assignments for my classes at Los Angeles Valley College.

On a positive note, the science teams are interesting, happy with their work, and pleasant to work with. I share a room with another scientist where I have the top bunk. I share lab “office space” with the Atmospheric Soundings group, but float around the ship to the library and other spots for a change of scenery. There is always something good to eat and every day there has been a fresh salad bar at lunch and dinner. The cooks are really nice and try hard to please everyone on the ship which everyone knows is an impossible task.

Office lab mates Lou Verstraete, National Center for Atmospheric Research (left), and Jonathan Wynn Smith, Ph.D. student, Howard University (right).

I was surprised that non-plastic biodegradable materials are dumped at sea and there is a lot of it on a cruise that lasts this length of time. The plastic is burned on the ship in an incinerator. Also, the ship engines operate 24/7 to keep the ship in a fixed location (the term used for a fixed location is “on station”).

Overall, the positives outweigh the negatives on this cruise. My work with the Ocean Mixing Group is going very well and the other scientists are extremely helpful and often contribute to the development of lesson plans for the classes I am teaching from the ship. The positive attitudes of these researchers more than compensates for any negative parts of the cruise. And, as I mentioned in a previous posting, there are endless opportunities for interesting photographs.

Meteorologists would like this cloud formation. (Photo By Jackie Hams)

This photograph is actually a red moon at night. (Photo By Jackie Hams)

November 21, 2011March 26, 2021

Jacquelyn Hams: 12 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 12, 2011

Weather Data from the R/V Revelle Meteorological Stations

Time: 1045
Wind Direction: 2580
Wind Speed (m/s): 2.8
Air Temperature (C): 28
Relative Humidity: 67.6%
Dew Point: (C): 21.4
Precipitation (mm): 40.3

PAR (Photosynthetically Active Radiation) (microeinsteins): 2274.5
Long Wave Radiation (w/m2): 429
Short Wave Radiation (w/m2): 659

Surface Water Temperature (C): 29.7
Sound Velocity: 1545.1
Salinity (ppm): 35.2
Fluorometer (micrograms/l): 65.5
Dissolved Oxygen (mg/l): 3.3
Water Depth (m): 4640

Wave Data from WAMOS Xband radar

Wave Height (m) 1.7
Wave Period (s): 12.8
Wavelength (m): 226
Wave Direction: 195⁰

Science and Technology Log

The Revelle is now on station and will remain in this location for approximately 28 days to conduct measurements of surface fluxes, wind profiles, C-band radar, atmospheric soundings, aerosols, sonar- based ocean profiling and profiling of ocean structure including turbulence. Please note that the exact position and course of the ship will not be posted in this blog until Leg 3 has been completed and the ship is back in port in Phuket, Thailand. Although piracy is not anticipated at the station location, it has been a problem in other parts of the Indian Ocean and the policy is not to publicize the coordinates of the ship.

Surface Fluxes

The Surface Fluxes group measures the amount of radiation and heat into and out of the ocean. There are several dome instruments on the Revelle to measure atmospheric radiation, acoustic and propeller sensors to measure winds and a “sea snake” to measure the sea surface temperature. The term flux is defined as a transfer or exchange of heat. The sum of the terms in the equation below indicates how much radiation is in the ocean. If the sum >0, the ocean is warming. If the sum is <0, the ocean is cooling. Below each term is a photograph of the ship-board instrument used to measure it.

Ocean Mixing

Today I deployed the Los Angeles Valley College drifting buoy. Before leaving Los Angeles, the students in my introductory Physical Geology and Oceanography classes signed NOAA stickers that I placed on the buoy before releasing it into the Indian Ocean. A drifting buoy floats in the ocean water and is powered by batteries located in the dome. The drifting buoys last approximately 400 days unless they collide with land or the batteries fail. The buoy collects sea surface temperature and GPS data that are sent to a satellite and then to a land station where the data can be accessed. Drifting buoys are useful in tracking current direction and speed. Approximately 12 drifting buoys will be deployed from the Revelle during Leg 3 of the Project DYNAMO cruise.

Personal Log

Can you have pirates before a pirate drill?

After we arrived on station, a science meeting was held to provide instructions regarding safety and emergency procedures for mandatory drills such as fire safety, abandon ship, and pirate drills. Drills are typically scheduled once a week and we have already assembled for a fire drill. A pirate drill was scheduled for the following week.

I began my orientation working with the Oregon State University Ocean Mixing Group. My role on the research team is to assist with the operation of the “Chameleon”, a specially designed ocean profiling instrument that is continuously lowered and raised to the surface taking measurements while on station. My job is to rotate between operating the winch (used to lower and raise the instrument) and the computer station. The computer station operator is in constant communication with the winch operator and tells the operator when to raise and lower Chameleon. In addition, the computer operator logs the critical start and end times of each run and keeps track of the depth of the instrument.

Jackie operates the winch. My goal is to keep the instrument safe and have a perfect wind.

I was just beginning to learn to operate the winch when an alarm sounded followed by the words “Go to your pirate stations, this is not a drill, repeat, this is not a drill”. I must admit I was a bit stressed. When I came on this trip, I knew there was a remote risk, but I thought it was extremely remote. Everyone assembled in the designated area and it turns out that a fishing boat was approaching the ship and the Revelle does not take chances if the boat appears to be approaching boarding distance to the ship. There have been two instances where we have assembled for safety following the alarm and the words “This is not a drill, repeat, this is not a drill.” In both cases, fishing boats were too close for comfort. As I began operating the winch, I watched a fishing boat off in the distance for a few days and became more comfortable knowing that the ship is taking extreme caution to protect all on board. All this excitement and before we even had a pirate drill!

But all is well somewhere out here on the equator and the Indian Ocean provides many opportunities for photographing amazing sunrises and sunsets.

Sunrise on the Indian Ocean (photo by Jackie Hams)

Sunset on the Indian Ocean (Photo by Jackie Hams)