Posts Tagged ‘ocean salinity’

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.

Salinity Processes in the Upper Ocean Regional Study (SPURS): What will happen aboard the R/V Knorr?

August 22nd, 2012 by Maria-Jose Viñas

By Eric Lindstrom

As I mentioned in my previous post, our cruise will depart from Woods Hole, MA on September 6. Roughly, it will take eight days for our ship, R/V Knorr, to transit from Woods Hole to the SPURS central mooring site at 25N, 38W, the saltiest spot in the subtropical North Atlantic. Then we will spend several days planning for and deploying sophisticated moorings bristling with instrumentation, which will remain in place for 12 months and provide a broader view of the mooring area’s physical properties, which will be our starting point for future, more localized ship-borne measurements. Details of moored instrumentation and how the approximately 5-kilometer (3-mile) long moorings are deployed will be the subject of my shipboard posts.

Testing of a SPURS Langrangian float in Puget Sound in August 2012.

With moorings successfully in place, we will deploy an extensive array of Lagrangian (free-floating) instruments.  There will be Argo floats that park at 1 km (0.6 mi) depth and periodically measure temperature and salinity measurements in the upper 2 km (1.2 mi) of the water column. We’ll also use surface drifters that measure surface temperature and salinity and the velocity of the upper ocean.  We’ll deploy several kinds of gliders that collect upper ocean temperature and salinity data along pre-programmed tracks. There will also be specialized profilers for measuring the temperature and salinity fine structure to help us understand mixing processes. We will deploy and use these during the middle weeks of the expedition, while leaving many instruments that will continue to collect data for six months to a year.

A SPURS mooring being tested.

Another aspect of the cruise is devoted to understanding the role of eddies (the swirls of ocean waters) in the circulation and the distribution of salinity. The cruise plan calls for finding and mapping an interesting front or eddy feature in some detail. My posts from the ship during that time will highlight the identification of the feature and how we chase it and measure it, and I will also describe the implications of our observations.

The expedition will wrap up with final checks of the instrumentation to be left behind, recovery of temporary deployments, profiles of temperature and salinity for cross-calibration of instruments and other duties that may arise.

We will use many of the kinds of instruments that are already deployed in a sustained, basin-wide observing system (surface drifters, Argo floats, moorings, and volunteer observing ships). What we will do with SPURS is expand the area we study, observe it for a longer time, and dig into the details. NOAA will be a strong partner throughout the SPURS mission, and I will tell you how we collaborate in future posts.

This mast measures ocean surface fluxes.

The chief scientist for the R/V Knorr leg of the SPURS experiment is Ray Schmitt from Woods Hole. Ray is funded by the National Science Foundation to examine salinity processes. NSF is an exceptional partner in SPURS – sharing the burden of ship support and helping to provide the scientists and equipment to study the smallest scales of variation of salinity. Their role is SPURS will also be detailed during the expedition posts.

All of the scientists and technicians involved in SPURS on R/V Knorr have numerous and specialized roles to play for the entire expedition to be successful. I plan on describing their personalities, work at sea, and motivations in future posts.

After approximately three weeks on site at the salinity maximum in the subtropical North Atlantic, R/V Knorr will make for Punta Delgada in the Azores Islands to turn over the ship to the next scientific party (not related to SPURS). It will take about 3 days at full speed to reach the Azores, where the ship is due on 9 October.

In my next post I will describe some of the shore-based and international collaborations that support SPURS.

Until then, smooth seas!

Notes from the Field