Notes from the Field

NAAMES-II Expedition: May 11, 2016

May 12th, 2016 by Kristina Mojica

This morning started out full of excitement. The weather was beautiful, sunny and relatively warm. The first nice day many of us experienced since we began trickling into WHOI over the last week or more. The day had finally arrived, we were leaving to start our expedition. Everyone was on deck, many skipping breakfast to witness the lifting of the gangway and the slow departure from shore. Then, to our dismay, we noticed that the gangway was being detached from the crane while still on the dock. We were soon informed that a technical problem had arisen on the ship and could not be corrected in time for us to leave within the small window created by the slack (low) tide. Unfortunately, this meant that we would have to wait 7 hours for the next window. During the science meeting that followed, chief scientist Mike Behrenfeld informed us that we would set sail during the coming high tide which would occur around 1500, irrespective of whether the technical problem could be solved. We have a 7 day transit to our first station and we are anxious to get there while the phytoplankton are still blooming. Needless to say, we are closely monitoring the event using ocean color satellite imagery.

10 day satellite composite from May1-10th of MODIS aqua Chl in the North Atlantic (units are mg m-3). Land is depicted in grey, clouds or ice in white. Figure provided by Toby Westberry.

10 day satellite composite from May1-10th of MODIS aqua Chl in the North Atlantic (units are mg m-3). Land is depicted in grey, clouds or ice in white. Figure provided by Toby Westberry.

The aim of the NAAMES-II expedition is to capture the peak of the bloom in the northern region of the North Atlantic and its’ inevitable decline as we progress southward. The hope is that the data obtained during the cruise will demonstrate underlying regulatory factors responsible for both bloom formation and decline. The underlying hypothesis being that the acceleration of the bloom occurs due to the positive affect of increasing availability of light on phytoplankton growth rate occurring in nutrient replete (rich) waters, and the offset between these increases in growth rate and parallel increases in mortality processes (such as viral lysis and microzooplankton grazing). In contrast, the deceleration would be a consequence of either phytoplankton growth rate stabilization when they achieve their light saturated maximum growth rate or growth rate decrease due to nutrient limitation of surface waters. In either case, mortality rates can “catch up” to phytoplankton growth rates. Once this occurs, mortality rates exceed growth rates and the bloom declines.

The delay did little to dampen the work occurring on board. Aside from the general science meeting, there were small meetings within groups which covered how measurements would be taken, the person responsible and the timing of schedules to make sure all bases would be covered and everyone would still get adamant rest while at station. There was also a general ship safety meeting which covered different alarm signals and how scientists should react to them. This was then followed by a fire and abandon ship drill. During the fire drill, scientists don life vests and muster in the main lab equipped with hats and survival suits in the event that abandoning the ship was required. During the abandon ship drill, several scientists wiggled into their survival suits to make sure they are capable of dawning them were the need to arise. This is always a humorous situation as it makes everyone look like big red gumbies.

Kelsey McBeain, a master’s student from the lab of Kim Halsey, dons the survival suit during the safety drills. Photo: Kristina Mojica

Kelsey McBeain, a master’s student from the lab of Kim Halsey, dons the survival suit during the safety drills. Photo: Kristina Mojica

After what seemed like an eternity, 1500 finally arrived. Once again, all scientists were on deck to watch the event. And there was nothing but smiles and high sprites as we moved away from the dock and waved our goodbyes to colloquies watching from shore. Finally, our expedition has begun. On our way out, we were blessed with calm seas and of course a beautiful sunset.

Sunset onboard the RV Atlantis after departure from WHOI, Photo:Kristina Mojica

Sunset onboard the RV Atlantis after departure from WHOI, Photo:Kristina Mojica

Comments are closed.