Right, where are we and what day is it? We had fish for dinner last night, so that was Friday. Therefore, I guess today is Saturday. Difficult to tell when you get into a routine and you are doing pretty much the same things every day of the week, starting in the dark and often finishing as it’s getting dark.
Oh yes, who’s doing the typing at the moment?
My name’s Glen and I am one of the PML science team here on AMT19. This is my fourth AMT cruise and by the end of this cruise I will have clocked up almost 30,000 miles up and down the Atlantic Ocean.
What I’m mostly involved with all begins with F: flowing, filtering and FlowCAMming. Along with other AMT19 colleagues I’m measuring how many plankton there are in the ocean: from tiny bacteria (small enough to fit about a million on a pinhead and up to 20 million in a teaspoon of seawater) up to tiny animals and plants about the size of a pinhead. Why? Well, we are very interested in knowing what’s out in the open ocean at different latitudes, how the communities change as we go from the North Atlantic to the south and seeing whether there are any changes happening over time.
To measure the plankton I’m using a variety of equipment.
My main tool is called a flow cytometer (hence the flowing) and it measures single celled bacteria and small phytoplankton and zooplankton. There are 5 similar flow cytometers onboard at the moment. I am using one of them and colleagues are using the others to study different things about the plankton.
PML’s flow cytometers in the main laboratory on RRS James Cook
FlowCAM
Another tool we are using is called a FlowCAM (hence the FlowCAMming) and that’s being used to measure and take pictures of larger plankton from about 20-1000 μm in size (1000 μm is about the size of a pinhead).
As for the filtering: in order to collect enough plankton to measure in the FlowCAM we need to filter plankton using a special net.
The microplankton net being constructed at the beginning of the cruise
Once we’ve filtered water from about 100 m depth up to the surface we put it in the FlowCAM and we can see pictures of the plankton.
Some of the things seen using FlowCAM. Zooplankton; (middle) tintinnid ciliate and (bottom left) copepod nauplius (baby copepod). Phytoplankton; (top) diatom and (bottom middle) dinoflagellate
It’s now coming up to solar noon (around 14:00 GMT) and that means it’s time for the ship to stop, deploy lots of different scientific equipment, including the plankton net and for all of us scientists to collect samples that will keep us busy for the rest of the day.