Louise Todd, From the Bridge, September 26, 2013

NOAA Teacher at Sea
Louise Todd
Aboard NOAA Ship Oregon II
September 13 – 29, 2013

Mission: Shark and Red Snapper Bottom Longline Survey
Geographical Area of Cruise: Gulf of Mexico
Date: September 26, 2013

Weather Data from the Bridge:
Barometric Pressure: 1012.23mb
Sea Temperature: 28.4˚C
Air Temperature: 29.6˚C
Wind speed: 6.43knots

Science and Technology Log:

This morning I went up to the bridge to learn about how the NOAA Corps Officers and the Captain navigate and maneuver the Oregon II.  Ensign Rachel Pryor, my roommate, and Captain Dave Nelson gave me a great tour of the bridge!

The Oregon II is 172 feet long and has a maximum speed of 11 knots.  It was built in 1967.  It has two engines although usually only one engine is used.  The second engine is used when transiting in and out of channels or to give the ship more power when in fairways, the areas of high traffic in the Gulf.  The Oregon II has a draft of 15 feet which means the hull extends 15 feet underneath the water line.  My stateroom is below the water line!  Typically the ship will not go into water shallower than 30 feet.

The bridge has a large number of monitors that provide a range of information to assist with navigation.  There are two radar screens, one typically set to a range of 12 miles and one typically set to a range of 8 miles.  These screens enable the officer navigating the ship to see obstructions, other ships and buoys.  When the radar picks up another vessel, it lists a wealth of information on the vessel including its current rate of speed and its destination.  The radar is also useful in displaying squalls, fast moving storms,  as they develop.

Radar Screen

The radar screen is on the far right

Weather is constantly being displayed on another monitor to help the officer determine what to expect throughout the day.

The Nobeltec is a computerized version of navigation charts that illustrates where the ship is and gives information on the distance until our next station, similar to a GPS in your car.  ENS Pryor compares the Nobeltec to hard copies of the chart every 30 minutes.  Using the hard copies of the charts provides insurance in case the Nobeltec is not working.

Charts

Navigation charts

When we arrive at a station, the speed and direction of the wind are carefully considered by the Officer of the Deck (OOD) as they are crucial in successfully setting and hauling back the line.  It is important that the ship is being pushed off of the line so the line doesn’t get tangled up in the propeller of the ship.  While we are setting the line, the OODis able to stop the engines and even back the ship up to maintain slack in the main line as needed.  Cameras on the stern enable the OOD to see the line being set out and make adjustments in the direction of the ship if needed.  The same considerations are taken when we are hauling back.  The ship typically does not go over 2 knots when the line is being brought back in.  The speed can be reduced as needed during the haul back.  The OOD carefully monitors the haul back from a small window on the side of the bridge.  A lot of work goes into navigating the Oregon II safely!

Personal Log:

I was amazed to see all the monitors up on the bridge!  Keeping everything straight requires a lot of focus.  Being up on the bridge gave me a new perspective of all that goes into each station.  We wouldn’t be able to see all of these sharks without the careful driving from the OOD.

The water has been very calm the past few days. It is like being on a lake.  We’ve had nice weather too!  A good breeze has kept us from getting too hot when we are setting the line or hauling back.

Did you Know?

The stations where we sample are placed into categories depending on their depth.  There are A, B and C stations.  A stations are the most shallow, 5-30 fathoms.  B stations are between 30 and 100 fathoms.  C stations are the deepest, 100-200 fathoms.  One fathom is equal to 6 feet.  A fathometer is used to measure the depth.

Fathometer

The fathometer is the screen on the left

Louise Todd, CTD and Samples, September 25, 2013

NOAA Teacher at Sea
Louise Todd
Aboard NOAA Ship Oregon II
September 13 – 29, 2013

Mission: Shark and Red Snapper Bottom Longline Survey
Geographical Area of Cruise: Gulf of Mexico
Date: September 25, 2013

Weather Data from the Bridge:
Barometric Pressure: 1008.6mb
Sea Temperature: 28.3˚C
Air Temperature: 26.3˚C
Wind speed: 8.73knots

Science and Technology Log:

After we set the line, the CTD (Conductivity, Temperature, Depth) is deployed at each station.

CTD

CTD ready to be deployed

This instrument provides information a complete profile of the physical characteristics of the water column, including salinity, temperature and dissolved oxygen.  The CTD is deployed from the bow of the boat using a winch.

Deploying the CTD

Deploying the CTD

When it is first lowered in the water it calibrates at the surface for three minutes.  After it is calibrated it is lowered into the water until it reaches the bottom.  The CTD records data very quickly and provides valuable information about the station.  Conductivity is used to measure the salinity, the amount of salt dissolved in the water.  The CTD also measures the dissolved oxygen in the water.  Dissolved oxygen is an important reading as it reveals how much oxygen is available in that area.  The amount of oxygen available in the water indicates the amount of life this station could be capable of supporting.  Dissolved oxygen is affected by the temperature and salinity in an area.  Higher salinity and temperature result in lower dissolved oxygen levels.  Areas of very low dissolved oxygen, called hypoxia, result in dead zones.  NOAA monitors hypoxia in the Gulf of Mexico using data from CTDs.

The otoliths and gonads are taken from all of the commercially and recreationally important fish like Snapper, Grouper and Tilefish.  Otoliths are used to age fish.  Aging fish provides information on the population dynamics for those species.  The otoliths are “ear bones” of the fish and are located in their heads.  It takes careful work with a knife and tweezers to remove the otoliths.

Removing otoliths

Removing otoliths

Once the otoliths are removed, they are placed in small envelopes to be examined in the lab in Pascagoula, MS.  Otoliths have rings similar to growth rings in trees that have to be carefully counted under a microscope to determine the age of the fish.

Otolith

Otolith

The gonads (ovaries or testes) are removed and the reproductive stage of the fish is determined.  The weights of the gonads are also recorded.  Small samples of the gonads are taken in order for the histology to be examined in the lab.  Examining the gonads closely will confirm the reproductive stage of the fish.  Gathering information about the reproductive stage of the fish also helps with understanding the population dynamics of a species and aids in management decisions.

Personal Log:

Taking the otoliths out of the fish was harder than I anticipated, especially on the larger fish.  It takes some muscle to get through the bone!

Otolith

Otolith removed from a Red Snapper

We have had a few very busy haul backs today.  One haul back had over 50 sharks!  My favorite shark today was a Bull Shark.  We caught two today but were only able to get one into the cradle long enough to get measurements on it.  We tagged it and then watched her swim away!  I can’t believe we are halfway through my second week.  Time is flying by!  I can’t wait to see what is on the line tomorrow!

Did you Know?

Yellowedge Grouper are protogynous hermaphrodites.  They start their lives as females and transform into males as they age.  Yellowedge Grouper are the only species of grouper we have caught.

Animals Seen

Here are a few of the animals we’ve seen so far!

Tilefish

Tilefish (Photo credit Christine Seither)

Sandbar

Sandbar shark in the cradle

Red Snapper

Red Snapper (Photo credit Christine Seither)

Yellowedge Grouper

Yellowedge Grouper (Photo credit Christine Seither)

Karolyn Braun, October 23, 2006

NOAA Teacher at Sea
Karolyn Braun
Onboard NOAA Ship Ka’imimoana
October 4 – 28, 2006

Mission: TAO Buoy Array Maintenance
Geographical Area: Hawaii
Date: October 23, 2006

The drifter buoy sets sail for its long journey on the sea.

The drifter buoy sets sail for its long journey on the sea.

Plan of the Day 

Very busy day. Was up bright and early to conduct the 600 CTD profile.  Had some breakfast and did some cleaning around the stateroom.  Around 9 a.m.  I updated my KA’IMIMOANA intranet webpage. I am glad I learned how to use the Frontpage program as it may come in handy. I went and sat in the ‘pool’ for a bit before lunch, but overall had a lazy morning.

After a light lunch we conducted a 4000m CTD cast, which took about 4 hours then deployed the AOML drifter buoy, the third of three that ASCC has adopted. The modern drifter is a high-tech version of the “message in a bottle”.  It consists of a surface buoy and a subsurface drogue (sea anchor), attached by a long, thin tether.  The buoy measures temperature and other properties, and has a transmitter to send the data to passing satellites.  The drogue dominates the total area of the instrument and is centered at a depth of 15 meters beneath the sea surface.  The drifter sensors measure data such as sea surface temperature, average the data over a window (typically 90 seconds), and transmit the sensor data at 401.65 MHz.  Each drifter transmitter is assigned a Platform Terminal Transmitter (PTT) code, often referred to as the drifter ID. These Bouys are deployed by NOAA’s Atlantic Oceanographic and Meteorological Laboratory or AOML.

While Tonya completed the CTD cast, I got to help the ship’s deck crew with a little Bosun Locker Clean-up. There was a pod of about 100 or so Pilot whales that crossed our path. Very cool to see! I got in a workout, then at 6 p.m. it was time to do another CTD profile.

Debra Brice, November 13, 2003

NOAA Teacher at Sea
Debra Brice
Onboard R/V Roger Revelle
November 11-25, 2003

Mission: Ocean Observation
Geographical Area: Chilean Coast
Date: November 13, 2003

Data from the Bridge
1. 131700Z Nov 03
2. Position: LAT: 10-01.0S, LONG: 084-55.0W
3. Course: 180-T
4. Speed: 12.5 Kts
5. Distance: 299.5 NM
6. Steaming Time: 24H 00M
7. Station Time: 00H 00M
8. Fuel: 4238 GAL
9. Sky: OvrCst
10. Wind: 130-T, 21 Kts
11. Sea: 130-T, 2-3 Ft
12. Swell: 140-T, 3-5 Ft
13. Barometer: 1013.8 mb
14. Temperature: Air: 22.4 C, Sea 19.0 C
15. Equipment Status: NORMAL
16. Comments: Drifter array deployment in progress.

Science and Technology

We are still underway towards the Stratus buoy. We spent the day deploying Surface drifters and 2 radiosondes. Surface drifters are small instruments attached to a “drogue” or sock that is about 40 feet long. The are thrown off the back of the ship while it is still moving. They will float on the surface and the drogue will float about about 15 meters below the suface taking sea surface temperatures and sending the data back to a satellite that is operated by the French ARGOS System. The data is downloaded at Wallops Island in Virginia and processed at various laboratories. We deployed 10 surface drifters today and will send off another group tomorrow. We are deploying them for the Atlantic Oceanographic and Meteorological Laboratory in Miami, Florida. This is a NOAA research facility. A noted drifter researcher is being done by Dr. Pieter Niiler at the Scripps Institution of Oceanography in La Jolla, Ca.

The purpose of the drifters is to measure sea surface temperature and check the accuracy ( calibrate) satellite data on sea surface temperature. Infra-red satellite data is sometimes blocked by stratus clouds and volcano eruptions. This brings to the light the question of why we need to go to sea in ships to study oceanography when we can supposedly get all the information we need from satellites. I will be interviewing Dr. Weller on one of my webcasts and he will address this question. Since I needed some additional enlightenment on why ships and shipboard research are still so essential to the study of climatology, atmospheric science and, of course, oceanography and Dr. Weller was busy today, I went to Scripps Institution of Oceanography ( via e-mail….those satellites are quite useful) and asked Dr. Robert Knox to help me out. Dr. Knox is the Associate Director of Ship Operations and Marine Technical Support and has helped me many times in the past with education outreach. The following is his wonderful explanation of why ships are still an essential tool for scientists in our exploration of the oceans and atmosphere.

Dr. Robert Weller’s research is an excellent example of why this type of data collection is so important and cannot be replaced by satellite data. It absolutely depends on using ships to handle his systems and is vital to gain a quantitative understanding of what the satellite sensors are seeing. In the absence of programs like Dr. Weller’s we could be seriously misled as to what the satellite data are telling us about the properties we actually care about, like sea surface temperature, heat flux between air and sea, etc. No satellite ever has measured or ever will measure sea surface temperature (SST). Yet we often see “satellite maps” of “sea surface temperature.” How? The satellite measures some component of electromagnetic radiation coming upward from the sea surface. That in turn can be related to the temperature of the sea surface, but only by way of a number of assumptions and calibrations having to do with basic physics of the radiation, the interactions of that radiation with whatever is in the atmosphere between the sea and the satellite, and on and on. In order to construct the formulas or recipes used to convert the radiation numbers to temperature numbers, real temperature measurements at the sea surface will always be needed to some extent, and with some distribution around the globe and over time. This is particularly true for long-term climate purposes, where slow changes in, for example, the atmospheric properties could lead to slow, subtle and unrecognized shifts in the correct recipes/formulas, and thus to unrecognized shifts in the deduced temperature results that were not real. Temperature is just one parameter. There are others, most of them harder to do via satellites.

The list goes on. Ships are needed for any number of laboratory-style experiments and measurements that simply cannot be done by remote sensors, but require samples of water, organisms or seafloor to be acquired and dealt with at sea. Questions in biology, chemistry and geology figure prominently here. New remote sensors, whether destined for satellites or unmanned vehicles in the ocean, in most cases require lengthy periods of development, testing and comparison against existing (shipboard) techniques before they can really be trusted to deliver the data desired – and even then (as in the case of SST above) there may well be an open-ended need for some level of ship-based, high-quality measurements to serve as a calibration standard in space and time. There are a host of chemical and biological parameters for which no remote sensor exists or is even imagined, yet shipboard/manned techniques do exist and can be used to answer important research questions. Take for example the identification and quantification of species or species assemblages in water samples (plankton, etc) and how these change over time, perhaps as a result of climate variations. If we waited until a remote sensor existed we might wait ad infinitum, yet we can do this identification and quantification now, using people and samples. The accumulation of those observations over time (more than 50 years thus far in the case of the CalCOFI program) sheds considerable light on the actual ecological changes taking place in the ocean and will continue to do so; we should most certainly not stop doing these measurements just because we cannot do them remotely. Or consider the business of measuring trace metals, notably iron, in seawater. This has gone from a curiosity to an important set of research programs in just the last couple of decades. It depends on exquisitely sensitive shipborne lab-style analyses of seawater samples for minute concentrations of these metals. Yet the tiny amount of iron in seawater may be a key limiting nutrient for phytoplankton under some circumstances. So iron trace concentrations get connected to important policy and economic questions such as whether deliberate iron fertilization could be a viable technique to enhance phytoplankton growth, thereby drawing down atmospheric CO2 via photosynthesis, and thus ameliorating greenhouse warming. Both the scientific and policy answers are far from clear at this juncture, but you can readily see the basic importance of the shipboard effort underlying the whole issue.

Finally, the advent of various remote sensors, on satellites and on unmanned vehicles, creates a whole new possibility for joint ship/other device campaigns that can do a much better job of focussed observation than has been possible in the ship-alone mode characteristic of nearly all history to date. The ship can serve as home base/deployment platform/data integration and analysis center/command post for adaptive, real-time control of a fleet of these devices, for ingesting streams of satellite data from overhead, and for deploying its own specialty ship-deployed instruments. Sort of a vision of the ship as the AWACS centerpiece of a flotilla or network of tools aimed at some common experimental objectives. Oceanography historically has been bedeviled by the inability to measure with coverage in both space and time matched to the problems of interest. A single ship can never be “here” and “there” simultaneously, nor can it cover the distance between “here” and “there” fast enough for some purposes. But operating as the mother ship/control center, many of these gaps can be closed. It’s going to be fascinating to see how some of these potentials are used in the coming decades.

Personal Log

As a teacher at sea one of the things I have learned in the short time I have been on the ship is that many times observing the conditions under which the data are collected can be as essential as the actual data itself in enabling a scientist to analyse it and put the data in the proper perspective. For example: when we retrieved the Equadorial Buoy and brought up all the instruments that were hanging on the mooring it was absolutely amazing to see the vast numbers of animals that had made these instruments their home ( see my pictures). Could these animals have effected the instruments and their data collections by blocking water flow or changing environment around the instruments? Yes. Is it important to note this and take this into consideration when analysing the data? Very possibly. The ship I am travelling on is named for a very famous and well respected oceanographer, Dr Roger Revelle, who understood how important it is for scientists to actively participate in the collection of their data by going to sea in order to get a more accurate perspective on what the data they collect is telling them about the oceans. As a teacher I hope I can share this with my students, I know that in my classroom, no amount of lecture or reading can replace the experience of doing a laboratory and collecting and analysing your own data. My watch is almost over and I have 2 more surface temperature readings to take before I sleep……the old fashioned way, drop the bucket with the thermometer over the side, fill it with water and read the thermometer. We are just checking those computerised sensors to make sure everything is working:)

Hasta manana