EOAS - CLIVAR Repeat Hydrography Cruise

Ambassadors, Scientists, and Science

In our complement of thirty scientists on this cruise, there are nine graduate and undergraduate students. One of our participants is a Miami-Dade County Public School high school teacher, Monica Mejia. Monica is working for Dennis Hansell, Rosenstiel School of Marine & Atmospheric Science (RSMAS), and Ann McNichol, Woods Hole Oceanographic Institute (WHOI), collecting samples for Dissolved Organic Carbon (DOC) for Hansell and Radiocarbon (¹⁴C) for McNichol.

Our cruise was covered by the Icelandic media. On July 31^st we hosted ambassadors to Iceland from the United States (Luis E. Arreaga), United Kingdom (Stuart Gill), and Norway (Dag Holter). Staff of the embassies from Germany and Russia were also present. They were given a tour of the ship, ship life and an introduction to the CLIVAR / Go-SHIP Repeat Hydrography / Carbon Dioxide Program. News of this tour appeared in local press and the Ambassador of the United State's web page at the links below.

Some photos from the start of the cruise to date (all pictures taken by Rachel Shelley).

Aug. 3, 2013, 8:00am - Leaving port
Harpa, the most expensive building in Icelandic history, is in the background

Aug. 3 - The pilot ship leaves us as we head out to the open sea.

Aug. 3 - The first CTD cast of CLIVAR A16N 2013!

Along with Conductivity, Temperature and Depth (CTD) measurements, this rosette samples water for chlorofluorocarbons (CFC), oxygen, nutrients, discrete pCO₂, dissolved inorganic carbon, pH, total alkalinity, helium, tritium, 14C, δ¹⁵N, colored dissolved organic matter, and salinity. On average, 2000 - 240 samples per station are taken.

Aug. 3 - Dr. Bill Landing prepares for the first trace metal cast, with Pam Barrett looking on.

Eric Stassinos (UCSB) at work in the main lab.
Eric is processing water for colored dissolved organic matter (CDOM).

Styrofoam cups in the main lab

Meteorological and details of the ship's position are displayed in the main lab. In the foreground you can see a net of Styrofoam cups and manikin heads. Styrofoam contains a lot of air. One of the cool things to do on a ship which samples from great depth (several 1,000 m) is to send decorated Styrofoam objects down with the CTD rosette. The immense pressure at these depths compresses the air and shrinks the Styrofoam objects to a fraction of their original size. Watch this space for more pictures related to this! ☺

Chris Langdon (UM), one-half of Team Oxygen, at his work station in the main lab.

Chris Langdon (University of Miami), is one-half of team oxygen. The other member of his team is Laura Stolenberg (visiting researcher, University of Miami). The dissolved oxygen (dO₂) concentration of the ocean is a sensitive measure of climate change. Dissolved O2 gets into the deep interior of the ocean via the subduction of cold, dense water at high latitudes. As polar ice melts, due to global warming, water becomes fresher and warmer, and, therefore, less dense. This slows down the resupply of dO₂ to the deep ocean. Over the years, Chris and his co-workers have noticed a steady decline in dO₂ concentration. This is bad news for things that live in the ocean. For example, fish such as tuna avoid low dO₂ waters, and change their migratory behavior accordingly. You may also have heard about oceanic 'dead zones'; there is a very large one in the Gulf of Mexico. Dead zones are increasing due to increasing agriculture run-off, for example. As dead zones increase, so does the area of the ocean that is avoided by fish. This has major implications for the future of fisheries.

Segmented-flow analyzer

The segmented-flow analyzer determines concentrations of the major nutrients in seawater (nitrate + nitrate, phosphate, silicate). This instrument is operated round the clock by two people, Eric Wisegarver (PMEL-NOAA) and Charlie Fischer (AOML-NOAA).

Anthony Dachille (LDEO) hard at work
Anthony is measuring δ¹⁸O, helium and tritium, and was on A16N in 2003

Some of the computers in the survey lab

Chief scientist, Molly Baringer, AOML-NOAA - Still smiling!

An awe-inspiring sunset. One of the best things about going to sea is the amazing sunsets and sunrises.

Joe Resing & Pam Barrett in the trace metal van

Joe is running water column samples for dissolved Fe and Al. Pam is controlling the deck box, which determines the depth at which the GO-Flo bottles close and sample water.