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South Pacific Bio-optics Cruise 2014: The Field Campaign Has Begun!

March 24th, 2014 by Aimee Neeley

The guys are finally on their way!  The R/V Nathaniel B. Palmer set sail from Hobart, Tasmania on March 20, 2014 ( GMT +11 hours).  The science party is made up of a total 29 scientists, 9 of which are graduate students. The first Go-SHIP station is located at 67°S, 150°W. While in transit, scientists will deploy the first Bio-Argo float of the campaign, 6 days from sail.  An Argo float is a battery-operated, autonomous float that can move up and down the water column collecting temperature and salinity profiles up to a 2000m depth by pumping fluid into and out of a bladder to manipulate buoyancy.  A Bio-Argo can collect measurements of chlorophyll-a and backscattering, in addition to salinity and temperature profiles.  The deployment of Bio-Argo floats is particularly important for validating ocean color remote sensing data.  For more information about Argo floats, you can proceed to the following links:

How Argo Floats Work

Bio-Argo Floats

First sunset photo by Mike Novak

First sunset photo by Mike Novak

Setting up a scientific laboratory on a ship is no easy task.  Space is usually limited and you must be able to play well with others.  We have filtration equipment (the large wooden frames) set up to collect the biogeochemical parameters, i.e. phytoplankton pigments, particulate organic carbon and particle absorption.  The parameters are collected onto small paper filters and frozen for future analyses back at NASA Goddard.  We also have two instruments set up on board to measure colored dissolved organic matter (CDOM), which is like tea, compounds extracted from plant material that can flow out into the ocean via rivers.  While in transit to the first station Mike, Joaquin and Scott are busy collecting samples.

Mike Novak filtering samples

Mike Novak filtering samples

 

Particles on a filter pad

Particles on a filter pad

Joaquin Chaves preparing samples for storage

Joaquin Chaves preparing samples for storage

A major addition to this year’s field campaign is a ‘souped-up’ underway-sampling system built by none other than Scott Freeman, our optics expert on board the Palmer.  The set-up contains multiple instruments that collect dissolved and particulate absorption, CDOM fluorometry, chlorophyll and particle scattering at 660nm.   The system is connected to the ship’s seawater system that pumps clean seawater from <10m depth through the ship and then to faucets at which the water can be accessed.  The term ‘clean’ means the plumbing that facilitates seawater pumping to the laboratories is routinely checked for clogs and algae growth.

Scott Freeman and the underway sampling system

Scott Freeman and the underway sampling system

Lastly, a blog post isn’t complete without a gratuitous photo of macrofauna.  Here is a photo of a petrel taken by Joaquin Chaves.  Can anyone identify what kind of petrel this is?

Flying Petrel

Flying Petrel

South Pacific Bio-optics Cruise 2014: The South Pacific Bio-optics Cruise: An Introduction

March 20th, 2014 by Aimee Neeley

Three members of the Ocean Ecology Laboratory’s Field Support Group (FSG; Code 616) will embark on a 45-day journey from Hobart, Tasmania to Papeete, Tahiti on the icebreaker R/V Nathaniel B. Palmer (NBP).  The field campaign is part of the US Repeat Hydrography, P16S, 2014 under the auspices of GO-SHIP and sponsored by the US Climate Variability and Predictability Program (CLIVAR).  You can find more information about the program here.  The FSG will collect biogeochemical samples and bio-optical data across the South Pacific.  These data will eventually be ingested into NASA’s SeaWiFS Bio-optical Archive and Storage System (SeaBASS) and subsequently used for ocean color satellite validation activities.

During the next six weeks, I will be helping my colleagues chronicle their journey over the high seas.  They will share not only information about the science but also describe the daily life of a sea-going scientist.  I, too, participate in many of these campaigns and am very familiar with the NBP having sailed on it three times during my career.  Alas, I could not participate in the journey so must live vicariously through my colleagues.  Below, you will find the biographies of the three NASA scientists that are participating on this cruise: Joaquin Chaves, Scott Freeman, and Mike Novak. You can also follow the ship track here.

Joaquin Chaves, received his PhD in oceanography from the University of Rhode Island in 2004. For his graduate work he conducted research on estuarine biogeochemistry. He held postdoctoral positions at the Marine Biological Laboratory in Woods Hole, MA, and at Brown University, in RI, where he focused on the biogeochemistry of land use change in tropical forests, particularly in the Amazon region. He’s been a contract scientist at NASA-GSFC since 2009, where he has focused on ocean color satellite remote sensing and marine bio-optics. He has participated in ocean-going field campaigns to the Atlantic, Pacific, and Arctic Oceans, as well as the East China Sea.

Joaquin Chaves

Joaquin Chaves

A native Californian, Scott Freeman grew up in Salinas, near the Monterey Bay, and attended the University of California, San Diego. After a lengthy hiatus in New York City, he returned to college and received a B.S. in Biology from the City University of New York. He then attended the University of Rhode Island’s Graduate School of Oceanography, completed a master’s degree, and stayed in Rhode Island to work first for the URI, and then for Wetlabs, a manufacturer of oceanographic optical instruments. While in Rhode Island, he participated in many cruises and coastal exercises, including NASA’s Southern Ocean Gas Exchange Experiment (SO GASEX) and ONR’s Radiance in a Dynamic Ocean experiments (RADYO).

Since joining SSAI in 2011, Scott has participated in several field campaigns for NASA’s Ocean Ecology Laboratory, and is responsible for AOP and IOP data collection and processing. He lives in Alexandria, VA with his wife Heidi and sons Charles and Adrian. When not engaged in field research, one can find him playing bass for the Washington Metropolitan Philharmonic Orchestra.

Scott Freeman

Scott Freeman

Mike Novak grew up in Piscataway, New Jersey, about 30 miles southwest of Newark.  After graduating high school he attended the Richard Stockton College of New Jersey where he earned a B.S. degree in marine science.  After college, he attended graduate school at the University of New Hampshire where he earned an M.S. degree in Oceanography.  He worked as a researcher at UNH before relocating to the Washington D.C. area where he now works as an oceanographic researcher at NASA-GSFC.  When he is not sailing the high seas, he is also an avid musician playing at various venues around the D.C. area with his band Novakaine.

Mike Novak

Mike Novak

Salinity Processes in the Upper Ocean Regional Study (SPURS): SPURS Epilogue (The First)

October 15th, 2012 by Maria-Jose Viñas

By Eric Lindstrom

“Ships at a distance have every man’s wish on board.” — Zora Neale Hurston

Actual spurs.

So, we are back in port in the Azores Islands of Portugal. Knorr 209-1 was a fabulous voyage and it did feel that we had many a man’s wish on board. Those included wishes for our data collection from all the scientists involved in SPURS and well wishes from all the family members of the expedition and finally the good wishes of you, my blog audience.

The Knorr SPURS science group.

Thank you all for following my SPURS adventure so far. The saga continues for another year. We have instruments in the water and more expeditions ahead (in March and September 2013). Each expedition will be slightly different in nature but overall working toward the SPURS goal of understanding the surface salinity maximum in the Atlantic and the water cycle on the planet. I’ll be going into a different mode of blogging now, to provide you updates on the science and the observations as the year goes along. With good fortune, I will get back to sea for the final leg of SPURS in September 2013. If you would like another voyage blog from the Sargasso Sea in 2013, let your voices be heard in the comments section below!

After several days of riding a lumpy swell from Tropical Storm Oscar, we were greeted by the magnificent sight of greenery and civilization at Ponta Delgada on the island of São Miguel.

Ponta Delgada’s water front.

Panorama of Ponta Delgada’s waterfront.

The Knorr in Ponta Delgada.

The expedition was a success scientifically.  We got our sensor web in the water for the coming year: three moorings, 25 Argo floats, 18 surface drifters, three Wavegliders, three Seagliders, and a Lagrangian Mixed Layer Float. We completed a wide variety of shipboard deployments: 764 Underway CTD casts, 100 CTD/LADCP Stations, 30 Vertical Microstructure Profiles, 33 AUV missions, three Slocum glider turbulence missions, and a full suite of continuous measurements including ocean velocity profiles, thermosalinograph and meteorology/fluxes. We accomplished the objectives we had laid out for us – deploy the sensor web (week 1), do a control volume survey around the moorings (week 2), and map a mesoscale ocean feature (week 3). We were able to squeeze in some extras, like a 24-hour time series in the saltiest water and pick up a glider from the French expedition in August.

The expedition was a success for NASA and WHOI.  We even caught the attention of the International Space Station and had a great 30-minute chat with Commander Sunita Williams about research in sea and space and the strong connections between the space program and oceanography.

The expedition was a success in interagency cooperation. SPURS is led by NASA, but has enormously important contributions from NSF, NOAA, and the Office of Naval Research.  It takes a village to put on a good oceanographic process study!

I created a “SPURS Illustrated Campaign Summary” from our Knorr expedition. I will make it available to all of you as part of a future post. There will also be movies available from the Space Station call and from the expedition, which are still in the editing process.

Your questions and comments on SPURS are always welcome. Use the comments section of any of the posts and I will get the message. Your interest and curiosity provides directions for future blogs and helps me put into words some of the technical aspects of SPURS that may not be fully understood.

Thanks you all for again following along on our Knorr SPURS expedition. There is much more to come, so stay tuned!

Salinity Processes in the Upper Ocean Regional Study (SPURS): Channel Fever

October 12th, 2012 by Maria-Jose Viñas

By Eric Lindstrom

Channel fever: an unusual excitement or restlessness common among a ship’s crew when the ship nears port after a voyage (The term probably refers to the English Channel, between southern England and northern France.)

Knorr-crew T-shirt for SPURS – there is no significance to the dinosaur as far as anyone knows.

Now that all the oceanography is done, it’s four days of steaming to the Azores. During that time there is still plenty to do. A shipping container is being prepared for freight to Woods Hole. People are comparing notes on their flights out of the Azores and taking guesses at what time we will be getting off the ship.

We are writing expedition reports (something your blogger has pretty well in hand!). I took over 2,000 pictures during the voyage and wrote 32 blog posts. I plan on finishing this trip with an epilogue as next posting. Then, after I return home, you will be able to access my presentation entitled “An Illustrated SPURS Campaign Summary,” which captures the entire expedition accomplishments in pictures. Remember too, if you have become a fan of SPURS, that there are more expeditions in 2013 and a sensor web in the water until next October. I will be blogging periodically to keep you up-to-date on developments and findings. For now, I need a rest from blogging. It feels like channel fever!

SPURS members writing reports.

Personal gear has to be packed and cabins cleaned. That leaves people with time to think about what they will be doing in the Azores or when they get home. People are laughing more and joking more. Sometimes, with all this activity, happiness emerges as channel fever.

Our bags are packed.

Does Julius have channel fever?

Maybe it’s the transformation of the ship – from being loaded down with gear to empty cleanliness. There are empty reels and baskets indicating our success at deploying moorings. The CTD master control station, hub of so much activity for the past weeks, is now quiet. Everywhere you look, it’s looking like its over. It’s enough to bring on channel fever.

The reels are empty now.

All the CTD stations are over.

We are taking stock at what we have done. We deployed three moorings, 100 CTD stations, 764 Underway CTD casts, 25 Argo floats, 18 surface drifters and a Lagrangian float. We left three Wavegliders and three Seagliders patrolling the seas near the moorings. The salinity field over a 120×120 mile piece of ocean was pretty well mapped. We have gigabytes of data to sift through and analyze. And we are pleased. We are weary. And we know when we see the Azores we are nearly home. That feels like channel fever!

We leave the lovely blue Sargasso Sea in our wake, but we can feel the harbor channel in Ponta Delgada, Azores in our future. We feel the accomplishment of the mission, and the promise of home. That is channel fever.

Salinity Processes in the Upper Ocean Regional Study (SPURS): Ocean Motion

October 11th, 2012 by Maria-Jose Viñas

By Eric Lindstrom

When on land, an oceanography brain usually associates the term ocean motion with the movement of seawater in the form of ocean currents.

Depictions of ocean surface currents derived from satellite data can be viewed at NASA’s OceanMotion.org web site.

However, when actually on the ocean, the biggest signal for our oceanography brains to cope with is the role of ocean motion in the pitch and roll of the ship (due to wind seas and swell). OK, so I am telling you that feelings matter. If you have ever been seasick, then you know what I am talking about!

So, if you spend 33 days on a small vessel at sea, you get a great appreciation of ship motion. There are actual six axes of motion of two kinds (lateral and rotational). Laterally there are surge (fore and aft), sway (port and starboard), and heave (up and down). Rotation also occurs around three axes that are more commonly discussed (maybe because we feel them more?). They are pitch (around port to starboard axis), roll (around bow to stern axis), and yaw (around the vertical axis). We can definitely feel all these motions but some do matter to our feelings more than others. Perhaps the most noticeable ones for land-loving creatures like humans are heave (the accelerating elevator feeling) and rotational motions largely absent in our daily lives (pitch and roll). Together, these can be combined into a kind of perfect storm of corkscrew-like motion that weakens the resolve of even veteran mariners. Lucky for us, the SPURS cruise has been pretty calm and no one has been suffering from seasickness.

By far the most noticeable and everyday motions on a ship are that of pitch and roll. Pitch is especially noticeable when navigating into a swell or into the wind. Going downwind or in the direction of the swell is much more gentle pitch-wise (sailors are wished good luck by offering them “fair winds and following seas”). Roll is especially diabolic when one is navigating nearly parallel with the troughs and crests of the swell. This is something you DO NOT do when the seas are large because you may very well roll over (not good; do not try this at home!). Faced with large seas, the safest course is to ride the weather facing into the wind and waves (and just suffer the horrible pitching).

Sorry to go on for so long about the ship motion, but its an ever present partner to our expedition and you deserve a share for sticking with us!

You may be wondering about the difference of wind seas and swell. Good question!  Swell and wind seas are both manifestations of surface gravity waves. Swell is caused by wind forcing of the ocean in some remote location. Wind seas are the jumble of more disorganized waves that come up directly under and within a wind event. There has been a good swell running in the SPURS region for the last two weeks due to Hurricane Nadine hundreds of miles away. On top of the swell, the wind waves cause whitecaps and noticeable roughness above wind speeds of about 10 miles per hour.

Well, on Knorr we are not out here to study wind waves (just feel them). I should get on to talking a little about ocean surface currents. Our main focus is the surface salinity and how it gets to be the way it is. Ocean currents moving patches of different salinity around is one key factor in accounting for salinity changes at any site in the ocean (we call this advection of salinity). The Ocean Motion web site produced for the NASA Physical Oceanography Program has a wealth of background information on ocean surface currents. Here in SPURS we believe there are only weak average currents (a year of moored measurements will determine that for sure), but that the wind-forced transient currents play an important role in the local water cycle (and surface salinity values). One obvious reason to think this is that the salinity maximum here is hundreds of miles north of the maximum in evaporation minus precipitation. The simplest explanation for this displacement is the northward movement of surface waters induced by the trade winds. On average, upper ocean waters forced by wind move 90 degrees to the right of the wind in the northern hemisphere so the easterlies of the trades give the ocean waters a push toward the north. This hypothesis will be tested by the SPURS observations over the coming year.

SPURS Argo float locations over time indicating flow at their parking depth of 3,300 ft. (Courtesy of Jessica Anderson.)

Out here it is extraordinarily difficult to fully appreciate the complexity of the currents around us in the upper ocean. The average current is small, but there are eddies and fronts with stronger flows around us that we observe sporadically as we move around from hour to hour.

Map of current vectors in the upper 167 feet (51m) along our track color coded by the surface salinity. (Courtesy of Phil Mele.)

We will only be able to make sense of our hour-to-hour estimates of ocean motion once we return to shore and can fully integrate the satellite and model information into the picture. We obtain details profiles of current vectors on each station but honestly have a tough time “connecting the dots” in real-time. It will take a good bit of analysis to understand the complex flow field.

Vertical variation of velocity vectors at three adjacent stations on the same day. (Courtesy of Julian Shanze.)

It feels a little like mapping Washington, D.C. in one day, from your car, driving around with a simple still camera. We get some great snapshots, but we can only place them in a larger context when be have full access to maps, satellite images, and historical records (stuff most people cannot examine in their car while driving around!)

As in rest of life, context is important in oceanography. We strive for it, but as with most things, the perspective of hindsight provides the best context. Feeling seasick is no exception! It’s so awful in the moment, and such a trifle in the glory of the entire expedition.