The Hansell Lab is at it again!

L-R: Andrew, Meredith Jennings, Sarah Sarah Bercovici and Prof. Dennis Hansell as we pass by the Space Needle in Seattle on the way to Puget Sound.

L-R: Andrew, Meredith Jennings, Sarah Sarah Bercovici and Prof. Dennis Hansell as we pass by the Space Needle in Seattle on the way to Puget Sound.

Our team left Seattle on August 4th, aboard the R/V Melville to sample Deep Ocean Refractory Carbon (or DORC) to understand the carbon deficit found in the North Pacific as deep waters overturn and form intermediate water. Over the past few days we moved all of our science equipment and personal belongs aboard while the ship was docked at the University of Washington, and everything has gone smoothly so far. On the 5th, we arrived on our first station and lowered the CTD-rosette to collect seawater samples throughout the water column. I will do my best to post to the RSMAS Blog over the course of our three-week cruise, but other students from the University of Georgia have setup two blogs, one science blog and one kids blog, to share what we are working on here in the Gulf of Alaska. The cruise website can be found at (with links to blogs and other info), the science blog can be found at and the kids blog can be found at!.html.

Wish us luck on this new scientific adventure!

Submitted by: Andrew R. Margolin, Graduate Student (Marine & Atmospheric Chemistry)

Deep Ocean Refractory Carbon cruise track and sampling stations marked as blue dots in the far Northeast Pacific and Gulf of Alaska.

Deep Ocean Refractory Carbon cruise track and sampling stations marked as blue dots in the far Northeast Pacific and Gulf of Alaska.

My Month At Sea Sampling Coastal Waters With NOAA

Before beginning at the Rosenstiel School, I had the opportunity to participate in NOAA’s second Gulf of Mexico and East Coast Carbon (GOMECC-2) cruise through the Cooperative Institute for Marine and Atmospheric Studies (CIMAS) at the University of Miami. After driving to Miami from Massachusetts and moving all of my belongings into storage, I moved on to the RV Ronald H. Brown, which would become my home over the next twenty-four days. We set sail from Miami on 21 July 2012, heading into the Gulf of Mexico to begin sampling and analyzing seawater for its physical and biogeochemical properties. We collected seawater throughout the water column using a 24-bottle rosette along eight transects that were approximately perpendicular to the coast, beginning the first transect near Louisiana and ending with the eighth in the Gulf of Maine on 13 August. In addition to the transects, we also collected surface water samples while in transit between each transect and the majority of the samples collected were also analyzed at sea aboard, keeping us busy during the course of the cruise. Analyses conducted at sea included salinity, oxygen, nutrients, dissolved inorganic carbon, total alkalinity, partial pressure of CO2 (pCO2) and pH, which will be used in conjunction with other parameters that are being measured in land-based laboratories to improve our understanding coastal ocean acidification.

My duties at sea were to collect seawater samples and perform the analysis of the pCO2 for all samples collected along the eight transects and while in transit. In addition to pCO2, I also collected samples for the analysis of total organic carbon (TOC), which I have here at RSMAS and have recently begun analysis in the Hansell Lab. Once I begin analysis, I will investigate TOC’s relationship with the other seawater properties that were measured and also compare TOC concentrations along transects in the Gulf of Mexico with transects on the Atlantic coast. As a result of my participation in the GOMECC-2 cruise, nearly 600 seawater samples were collected for TOC analysis along seven sections and approximately 1,200 seawater samples from all eight sections were analyzed for pCO2 by me and my supervisor, Kevin Sullivan (CIMAS).

The responsibility of collecting and analyzing samples was typically shared by two people, alternately working around the clock on opposite, twelve-hour shifts. For the GOMECC-2 cruise, the majority of the scientists had shifts beginning and ending at 3 o’clock, however, the pCO2 shifts began and ended at 1 o’clock. I had the shift that began at 1 am, which was challenging to get used to and to get back to a normal sleep schedule after the cruise, but during the cruise I couldn’t have been happier with my shift. I was able to overlap with the 3 pm to 3 am shift for a couple hours and get to know that group while sampling from the rosette or while taking a break to gaze at a sky full of stars, highlighted by the glowing Milky Way. It was also nice to get to know the people who I spent the majority of my shift working with while sampling on deck, watching sunrises together or enjoying meals together. My shift was perfect for maintaining high morale over the course of the cruise.

Every morning I woke up it would be dark and I would have my typical breakfast of instant oatmeal, occasionally topping it off with a left over dessert from the day before. I always worked through the 3 o’clock shift change and had an assortment of friendly faces to work with, which made the morning go by extremely fast. Sunrise always marked the middle of my shift, whether I was on deck sampling or taking a quick break to watch the sky brighten with an assortment of colors and feel the warmth that came along with the sun, reminding me that breakfast would soon be served. After breakfast remained a half day of work, which always found ways to surprise me with visits from pods of dolphins or pilot whales, or even schools of sergeant major fish on a detour to the Dry Tortugas National Park that we took before exchanging chief scientists in Miami.

The GOMECC-2 cruise was twenty-four days long and a great opportunity for me to meet scientists and students from universities in the eastern United States, as well as to meet scientists from RSMAS, CIMAS and NOAA. It was also a great opportunity for me to establish myself as a part of the RSMAS family before beginning graduate school, and I look forward to the next opportunity to participate in a NOAA research cruise.




RV Ronald H. Brown:

ocean acidification:

Hansell Lab:

Dry Tortugas National Park:

Andrew R. Margolin is a first-year Ph.D. student in the Marine & Atmospheric Chemistry Division at the University of Miami’s Rosenstiel School of Marine & Atmospheric Science.