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

August 23rd, 2016 by Maria-Jose Viñas

By Eric Lindstrom

Denis Volkov taking a break from work in the afternoon.

Denis Volkov taking a break from work in the afternoon.

One of the popular topics of conversation during the first week of the voyage has been sleep. Whether it is poor sleep, good sleep, disturbed sleep, or deep sleep, almost everyone in the science party has had something to say about the subject of sleep.

Sleep on a ship is special. As you can imagine, the rocking and rolling (actually pitching, rolling, and yawing) can be a gentle sleep inducement – unless it is making you terribly sick! What those on land probably cannot imagine are all the noises associated with the ship – the engines, equipment, and the sea slapping at the ship. An amazing array of new hums, grinds, bangs, bumps, slams, alarms and conversations must be assimilated into one’s sleep life.

After a week of hard work preparing the ship for sea in Honolulu, it is no surprise that many slept well the first night. However, the next couple days were much harder for some. The mild seasickness and the abnormal noises from the ship unsettled sleeping patterns. More than one person commented to me that their adjustment and best sleep came around day 5. By that time all the seasickness had past and the sounds of being at sea had been incorporated into ones dreams. Soon we will start weeks of 24/7 operations and the luxury of long sleeps may be over until the transit back to Honolulu. Sleep may get interrupted when operations call.

Audrey and Kristen during the early seasick times.

Audrey and Kristen during the early seasick times.

Many scientists will be on 12-hour watches (noon to midnight or midnight to noon) so one should not be too worried out lack of sleep among your favorite scientists. It is more likely that one’s normal rhythm of sleep may be at odds with duties.At sea it is not abnormal to find people eating, sleeping, exercising, and working at odd hours.

Part of writing about sleep now is because (at this writing on Sunday afternoon, August 21) we have completed our transit from Honolulu to 125W longitude and are beginning 24-hour scientific operations with a southbound trek along the meridian. We will be deploying drifters at regular intervals, profiling temperature and salinity while underway, and deploying three moorings along this meridian.

 Monkey working on his “monkey tan” at steel beach.


Monkey working on his “monkey tan” at steel beach.

Let me finish today with a little local story about sleep. Andrew Meyer, the mooring technician from the National Oceanic and Atmospheric Administration, has a son, Jack, who is 3 and a half years old. Jack sleeps with his plush toy Monkey every night. When dad left home for the SPURS-2 expedition, Jack sent Monkey along so Andy would not be lonely. So Monkey is having a good time, sending pictures to Jack and family regularly. Monkey is certainly helping Andy keep in touch with his loved ones and that also means that Monkey is helping Andy sleep better at night. So, dear readers, Monkey joins the blog today to honor all that we do to sleep well and to remember those we left at home as we work, and sleep.

Sunset at sea on Aug. 21.

Sunset at sea on Aug. 21.

I leave you today with a sunset and hope that all of you will sleep well!

Salinity Processes in the Upper Ocean Regional Study (SPURS): Meteorology for Oceanography

August 22nd, 2016 by Maria-Jose Viñas

By Eric Lindstrom

Launching a balloon from the R/V Revellle, for atmospheric sounding.

Launching a balloon from the R/V Revellle, for atmospheric sounding.

As I mentioned in a previous blog post, the R/V Revelle is bristling with meteorological sensors. Some are permanently installed aboard, some are just for SPURS-2, and some are on the moorings we will deploy. Raymond Graham, a graduate student at University of Connecticut, did a quick count of meteorological sensors and we were amazed to find out that on a ship of less than 300 feet we had deployed eight wind sensors, 16 air temperature probes, 15 humidity sensors, 15 rain gauges, 11 radiometers, and four barometric pressure sensors! The reason for the overkill is the critical nature of meteorology for our work and the difficulty of obtaining clean data from the ship. Wind and rain especially are notoriously difficult to sample because of flow distortions or shadowing around the ship. By deploying gear at a number of locations (bow, stern, bridge deck, etc.), we will more likely collect clean data no matter which direction the ship is headed relative to the wind. During analysis of the data, one ideal time series of ship data can be assembled from the numerous sensors based on ship heading and true wind direction.

Carol Anne Clayson at work on the bow mast.

Carol Anne Clayson at work on the bow mast.

For SPURS-2, a group from Woods Hole Oceanographic Institution led by Carol Anne Clayson and a group from University of Connecticut led by Jim Edson are gathering state-of-the-art measurements of key meteorological variables. They will estimate the transfers of heat, freshwater, and momentum between atmosphere and ocean. Today, for example, Jim Edson launched the first of their balloons for atmospheric sounding. The balloon carries a small expendable package that transmits temperature, humidity, and pressure data until the balloon pops in the upper atmosphere.

Elizabeth Thompson from the University of Washington's Applied Physics Lab.

Elizabeth Thompson from the University of Washington’s Applied Physics Lab.

Elizabeth Thompson from the University of Washington’s Applied Physics Laboratory is also working the meteorological angles for SPURS-2 by providing the daily meteorological briefings and analysis of radar data (to help us track rain events). She and Audrey Hasson are providing daily briefings at 4 pm to apprise us of the weather and oceanographic conditions to be encountered over the next day of operations. For the moment they are practicing and perfecting the best information and products to utilize and share. Prediction sure is an activity to sharpen a scientist’s skills!

Jim Edson from University of Connecticut  and Raymond Graham, a graduate student at U.Conn., looking over the first results from the balloon deployment.

Jim Edson from University of Connecticut and Raymond Graham, a graduate student at U.Conn., looking over the first results from the balloon deployment.

While much of the time aboard Revelle is focused on oceanographic measurements, the meteorology is key to synthesis of the overall story of SPURS. In the end we will want to assess the ocean response to forcing – whether in the form of rain, wind, or sun’s radiation. It is quite difficult to tell the story of the near surface ocean without understanding how it is interacting with the atmosphere. Likewise, it is quite difficult to tell the story of the evolving atmosphere without understanding how it interacts with the ocean. This coupled system is an especially powerful engine for Earth’s climate here in the tropics. The warmer the ocean and atmosphere, the more energy in the form of water vapor is exchanged. Hurricanes are a good example of this interaction and exchange – and a reason to worry about stronger or more frequent hurricanes in a warmer world. Air sea exchange is very sensitive and very powerful when ocean waters are greater than about 83 degrees Fahrenheit (28.5 degrees Celsius) as is found in the deep tropics and here in the Intertropical Convergence Zone.

Salinity Processes in the Upper Ocean Regional Study (SPURS): Preparing for Action

August 17th, 2016 by Maria-Jose Viñas

By Eric Lindstrom

Our wave gliders, ready for action.

Our wave gliders, ready for action.

Fieldwork in physical oceanography, like many sciences, requires enormous preparation followed by a shorter very intensive period of action. SPURS-2 is no exception. The work over the next six weeks has been in the planning and staging for several years. Now, all the gear and scientists have reached the ship and we are on our way to completing all of our the carefully laid plans.

It is tempting to express the mood aboard the R/V Revelle as a great sense of anticipation. From discussion around the ship, it seems like no one has seen a voyage with these many sensors and equipment installed aboard this ship. There seem to be instruments mounted everywhere from bow to stern! And, of course, the scientists and technicians are deeply interested in what each sensor will tell them and what kind of scientific discoveries will emerge. These instruments are designed to see the delicate slow dance between the ocean and atmosphere around the ship over the coming weeks. Other gear will be deployed to continue the careful watch on ocean and atmosphere for the next year. All our time and investment is focused on understanding the aspects of this “slow dance” that involve water exchanges between ocean and atmosphere. In the atmosphere we will be looking at the characteristics of rainfall and evaporation at the sea surface. In the ocean we will be study the characteristics of the temperature and salinity patterns induced by the rain. These interactions are a newly accessible field of study resulting from the advent of satellite rainfall and salinity measurements and new shipboard tools for studying the upper few meters of the ocean.

One of the numerous meteorological masts installed on the R/V Revelle for SPURS-2.

One of the numerous meteorological masts installed on the R/V Revelle for SPURS-2.

All the scientific party on R/V Revelle likely feel some sense of adventure, since the precise nature of what we will see and discover is a matter of conjecture. We do know from the Aquarius satellite data that there is a large pool of relatively fresh water built up seasonally at the surface of the eastern tropical Pacific north of the equator. Oceanographers are curious as to how this pool is trapped in the region for part of the year and how it is seasonally released to the west. As physicists, we are tackling the problem by careful examination of the individual processes that bring the water into the ocean (rain), maintain the fresh pool in the ocean (dynamics), and subsequently release the water to the west or to the deep (dynamics and mixing). If we knew the answers, it wouldn’t be research. The unknown beckons! The combined feelings of curiosity and anticipation –and that our work may result in deeper understanding of nature–, just seem to make this feel like an adventure!

The chief scientist of SPURS-2, Andy Jessup, is ready for action too.

The chief scientist of SPURS-2, Andy Jessup, is ready for action too.

So here we are, all primed for discovery but with five days more to go before being where we really want to work. We are like kids in the back seat of the car asking “are we there yet?” Every piece of gear is at the ready and the teams are completing their training. We are doing dry runs to iron out the deployments of new devices that just have not seen that much action. In later entries, I’ll introduce you to the Sea Snake and the Surface Salinity Profiler and the Lighter-than-Air InfraRed System (LTAIRS), a balloon. These are very new ways of examining the air-sea interaction near the ship. They will be used in conjunction with many of our standard tools – drifters, wavegliders, and moorings, for example. We hope they will lead us to deeper insights about the water cycle at the ocean surface. I will give you a preliminary view of what is discovered during the week-long return voyage to Honolulu at the end of September. For now, we simply prepare for action!

Salinity Processes in the Upper Ocean Regional Study (SPURS): Packing and Departure

August 15th, 2016 by Eric Lindstrom
The Lady Amber and R/V Revelle in Honolulu.

The Lady Amber and R/V Revelle in Honolulu.

By Eric Lindstrom

Two ships in Honolulu were abuzz with action this last week preparing for SPURS-2, a detailed study of ocean salinity in the eastern tropical Pacific Ocean. The Roger Revelle, upon which all the scientific party sails, had to be loaded with many tons of scientific equipment and installations completed all over the ship. Lady Amber, the 20-meter (66-feet) schooner, was also readied for action with the installation of meteorological and oceanographic gear.

It was amazing to see what was completed in only a week under the supervision of chief scientist Andy Jessup (University of Washington). Containers from Seattle, Woods Hole, and San Diego were unloaded and equipment hauled to the ships. Many scientists and technicians dedicated the entire week prior to Revelle’s departure on August 13 for stowage, assembly, installation, testing, and securing of instruments and gear. It was a very quiet ship over the last 24 hours after we departed as everyone had a well-deserved rest and acquired their sea legs!

The Lady Amber crew successfully tested its new installation of scientific gear but suffered a schedule setback when the crew discovered that the ship required a new engine prior to departure from Honolulu. These arrangements are underway and we are appreciative of the support provided by the University of Hawaii as the Lady Amber work gets completed. Lady Amber is expected to leave Honolulu in about a week and catch up with Revelle at the SPURS central work site, eight days southwest of Hawaii.

Argo the cat, relaxing in the Lady Amber.

Argo the cat, relaxing in the Lady Amber.

Weather was fine on Saturday afternoon for Revelle departure. It was a quick trip out of the harbor with a great view of Waikiki skyline and Diamond Head. We passed by the Big Island of Hawaii on Sunday morning, August 14, giving people one last chance at cell phone calls. The island, really the largest mountain on our planet (from ocean bottom to summit), is a phenomenal sight.

Goodbye to Honolulu!

Goodbye to Honolulu!

On Sunday we had our first of weekly safety drills. Everyone got to learn how to decode the various horns that call for assembly, all clear, and abandon ship. We learned about survival suits and life raft deployment. Especially, we learned how to be safe on the Revelle and watch out for one another. We were encouraged to see the expert knowledge and conduct of the crew in their drills. It is over 2000 miles from Hawaii to the site where we begin work in earnest (deployment of moorings that pack the after deck). In the coming week, as we make the transit, the primary occupation will be testing and checking out various systems and training everyone for the complex operations to come. Once we are on site, we will quickly enter 24/7 scientific operations and we hopefully will have worked out all the glitches!

On a sad note, we had to leave our colleague Fred Bingham standing on the wharf in Honolulu, when we had expected him to sail with us. He was struck down with an illness that required he remain ashore and head home to Wilmington, North Carolina. His primary role in SPURS is as data manager. We are all assured that he will be on the mend very soon but we will miss his sunny manner and organizational skills.

The scientific party aboard Revelle is quite diverse – from first timers to old veterans. I’ll try to introduce you to the team in the weeks ahead. I am happy to report that I have seen no severe cases of seasickness during our initial day at sea. No doubt a few people are feeling a bit “green” but all are adapting well.

As always, I welcome your comments and suggestions for this blog. Send your messages to ejlindstrom@rv-revelle.ucsd.edu (case sensitive!). The expected frequency of the blog will be about one every two days.

South Pacific Bio-optics Cruise 2014: Societal Benefits of Ocean Color

May 10th, 2014 by Aimee Neeley

My apologies for the gap between blog posts.  My day job has been pretty busy.  And even though the NASA folks have already arrived safely to Tahiti as of May 5,  2014, I thought it was fitting to have one last blog post. We have talked a lot about ocean biogeochemical sampling, ocean chemistry, and ocean color radiometry.  It is also important to touch on the societal benefits that ocean color radiometry can provide.

In 2007, the  International Ocean-Colour Coordinating Group or IOCCG published a report and an additional brochure entitled: “Why Ocean Colour?  The Societal Benefits of Ocean-Colour Technology” and “Why Ocean Colour.”  I will not go into all of the information detailed in each document here (though feel free to follow the links below at your leisure.)

IOCCG reports

IOCCG reports

A number of critical uses for ocean color are of particular importance in today’s society. For instance, detection of high algal biomass can indicate the location of potential fishing zone.  Fish that eat algae or fish that eat fish that eat algae (did you get all of that?) will be en masse in these blooms.  Inter-annual variation in timing and extent of phytoplankton blooms can also affect the survival of larval fish.  Satellite imagery can be used to monitor this variation.  Moreover, satellite derived sea surface temperature (SST) and wave height information can help aquaculture developers plan where to establish new fish farms.  Satellite imagery can be used to detect and monitor blooms of harmful algae, algae (phytoplankton) that ether produce toxins or can clog the gills of fish and invertebrates because of high biomass.

Harmful Algae Bloom in Lake Erie  http://oceanservice.noaa.gov/hazards/hab/

Harmful Algae Bloom in Lake Erie
http://oceanservice.noaa.gov/hazards/hab/

Satellite ocean color imagery is also very important for monitoring delicate ecosystems, particularly in global coastal environments.  For example, the European Space Agency (ESA) has developed a program called CoastWatch that helps scientists harness the power of satellite imagery for monitoring water quality in shipping channels and coastal environments.  The Medium Resolution Imaging Spectrometer (MERIS) on the Envisat platform (similar to NASA’s MODIS instruments) can be used to monitor sediment deposition onto coral reefs, which can smother the corals.  The imagery can also be used to monitor water quality in shipping channels after dredging.  Dredging can increase suspended sediments and negatively affect water quality.

MERIS image: sediments flowing onto reef http://www.esa.int/Our_Activities/Observing_the_Earth/ESA_s_sharp_eyes_on_coastal_waters

MERIS image: sediments flowing onto the Great Barrier reef in Australia
http://www.esa.int/Our_Activities/Observing_the_Earth/ESA_s_sharp_eyes_on_coastal_waters

Let’s consider a recent ecological disaster: the Deepwater Horizon oil spill. The Deepwater Horizon oil spill has been called the ‘worst oil spill in U.S. history’. The oil spill resulted from an oil platform explosion that occurred on April 20, 2010, and leaked an estimated 4.9 million barrels of oil by the time it was capped on July 15, 2010.  This type of disaster can have long-term impacts on coastal wildlife and fisheries.  Immediately following the spill, fishing areas around the Gulf Coast were closed to prevent human exposure to dangerous chemicals, polycyclic aromatic hydrocarbons, found in the oil.  These chemicals are known to cause cancer. The fisheries were deemed safe and reopened on April 19, 2011.

Oil in the marshes of the Mississippi Delta  http://ocean.si.edu/gulf-oil-spill

Oil in the marshes of the Mississippi Delta
http://ocean.si.edu/gulf-oil-spill

Dolphins swimming through the oil patches from the Deepwater Horizon spill http://ocean.si.edu/gulf-oil-spill

Dolphins swimming through the oil patches from the Deepwater Horizon spill
http://ocean.si.edu/gulf-oil-spill

Satellite ocean color imagery can be used to locate and monitor oil spills of this magnitude.  Although this type of imagery is complex, the technology is a great asset.  The video below, developed by video producers here at NASA Goddard, shows a timeline of NASA MODIS satellite images. Such imagery allowed scientists to follow the track of the oil slicks.  These images can help us prepare for the impact of these disasters when we know where it is headed next.  You can find satellite images of the oil spill here.

 

Satellite image of oil slick in the Gulf of Mexico following the sinking of the Deepwater Horizon platform  http://www.nasa.gov/multimedia/imagegallery/image_feature_1649.html

Satellite image of oil slick in the Gulf of Mexico following the sinking of the Deepwater Horizon platform
http://www.nasa.gov/multimedia/imagegallery/image_feature_1649.html

We have truly enjoyed sharing our experiences with all the blog readers.  I hope we can do this again very soon.  Until next time, make sure you check out all of the NASA field campaigns here at the Earth Observatory website.

http://www.ioccg.org/reports/report7.pdf

http://www.ioccg.org/reports/WOC_brochure.pdf

http://www.esa.int/Our_Activities/Observing_the_Earth/ESA_s_sharp_eyes_on_coastal_waters

http://www.esa.int/Our_Activities/Observing_the_Earth/New_ESA_project_supports_aquaculture

http://ocean.si.edu/gulf-oil-spill

http://www.nasa.gov/topics/earth/features/oil-spill-video.html

http://www.nasa.gov/topics/earth/features/oilspill/index.html

http://oceanservice.noaa.gov/hazards/hab/

Notes from the Field