Programs Blog

July 18, 2023

Olivia Patrinicola, B-watch, University of South Carolina, Marine Science

Ship’s Log

Location
0° 50.8’ S x 176° 15.5’ W, going to cross the equator again as we head back north toward Baker Island and the boundaries of the PRINMM to sample the western sides of the seamounts

Weather
Winds east by south, Force 5

Souls on Board

All blogs from S-310

My favorite part of this journey is the time I get to spend in the laboratory. While I really enjoy working on deck and being a student steward, working on science is by far the best part. My fellow students and I have all chosen research projects that the crew has helped us to gather data on. There are projects on zooplankton, phytoplankton, seafloor depth, seabirds, and my project that I share with Hallie: partial pressure of carbon dioxide. Every day, twice per day, the science crew launches a series of deployments that gather samples to be processed and analyzed. Each set of deployments requires the boat to gybe, then heave-to, which means we alter the sail angles to make the Robert C. Seamans stop moving forward, and slide more slowly slideways.

The first deployment is a phyto-net. The net is made of fine mesh and is shaped like a cone with a cup on the end. When the boat is hove-to, the net gets thrown into the water to float below the surface for about thirty minutes. When the net is pulled back up, it contains all this goop that can be further analyzed under a microscope.

Next, the hydrocast gets deployed. This process requires a few more hands than the phyto-net. The hydrocast is on this circular carousel which contains about twelve opaque bottles. Each of the bottles is programmed to shut at varying depths in the water column. The hydrocast also contains a device to measure fluorescence, dissolved oxygen, photosynthetically available radiation (PAR), and chlorophyll-a. The carousel is connected to a long wire (which can be dangerous if not handled carefully) that can reach great depths. The water collected from the hydrocast gets placed into bottles so that they can be processed later. Samples for pH and alkalinity are collected from the same bottles. They both go into dark glass bottles that are carefully filled to avoid the introduction of bubbles to the sample. Samples for pH get run through a spectrophotometer (measures the samples for light absorbance) which can be further converted to a value. The alkalinity samples are processed by titration using hydrochloric acid. This is my favorite process. The last samples collected from the hydrocast are for chlorophyll-a. The samples are collected in large, opaque, plastic Nalgene bottles. The samples are each filtered with a vacuum pump, and the filter is analyzed for chlorophyll-a concentration.

The third and fourth deployments are the shallow and deep tucker trawls. These are done while the sailboat moves at about two knots. These are again deployed using the wire and are towed for about twenty to thirty minutes. The samples are then analyzed for zooplankton and other interesting organisms. We use the microscopes to analyze the organisms.

The last one is the Neuston net. This is another fine mesh net that is cone shaped and has a plastic cup screwed on at the end. The neuston net (or “neusty” for short) is a larger version of the phyto-net that gets towed along the side of the boat as we slowly move along. The neuston net is thrown off the side of the boat and towed for thirty minutes. Afterward, the net is examined and analyzed under the microscope. Sometimes, the graduate students (Allie and Abby from the Rotjan lab at Boston University) find cool organisms such as blue bottles and man-o-wars.

The project Hallie and I are working on sounds fairly simple. But it has proved to be surprisingly challenging. We collect pH and total alkalinity data, which can be plugged into a crazy formula which can tell us partial pressure of carbon dioxide. The formula requires Henry’s constant and the hydrogen ion value which can be calculated from pH. We will also be comparing the carbon dioxide partial pressure with the deep chlorophyll maximum. This can tell us something about where the greatest concentration of carbon dioxide is, and if there is a relationship with the number of phytoplankton there. We are both so excited to go over our results at the close of our trip. As environmentalists, adding data to the pool in efforts of monitoring climate change is extremely exciting, and we cannot wait to see how far we come.

To Mom and Dad: I miss you so much, and I hope the trip to Germany was so fun. I can’t wait to see you guys, Noah, Liam, and Frankie again in Columbia in a few weeks. I hope Noah is having fun with his last high school summer and that Liam is crushing summer swim and cross country summer training. To my friends from home: I am getting very tan, so you all might need to catch up! I hope you all are having a wonderful summer and spending lots of time at the beach and maybe a Richmond trip? Time to start planning your August birthday party soon! To my friends at school: I don’t even know if you all are reading these, but I am excited to see you all soon and I miss you all. Getting super excited to go to some football games and going to Jakes for the first time. To Will: I hope you are documenting all of your adventures white water rafting, because I want to hear about it all. I am learning some celestial navigation skills that I think you might find interesting. Looking forward to seeing you soon!

Love you!

Olivia Patrinicola (B-watch, University of South Carolina, Marine Science)

“Tea time” in the red light of the lab during dawn watch with Olivia (left), Izzy (center), and Carly (right)