by Penny Holliday
Since the early hours of this morning we have been experiencing what feels to me like the real subpolar North Atlantic. The pressure dropped as we worked our way south of Greenland, and by breakfast time this morning the wind was up to 30 knots and the waves were building. We have to stop CTD work when these conditions take hold, because it becomes too dangerous to put the CTD in the water for a number of reasons. One is that it is difficult to hold the ship on station in strong winds, heavy seas and a strong surface current (we were in the West Greenland Current still). Another is that with each roll of the ship the drag and lift on the CTD package and the cable is dangles from, go from one extreme to the other and that will damage the wire and the winch or even cause the CTD to break off. And finally, it’s just too dangerous to be out on deck in that weather.
The winds picked up to 40 knots, and as the forecast suggested there might be better working conditions further south, the Principal Scientist and the Captain decided to break off work at that location and steam on to a different place. The ship turned and we took a course that had the waves coming towards our port stern. We stayed on that course for much of the day and it was reasonably comfortable even as the winds got up to 50 knots. Just before dinner we altered course to aim for our new station position, causing a huge roll as we turned and a few more since. Scientists had already been around the labs checking that every thing was lashed down and securely stowed; laptops, cups and small bottles can be especially vulnerable in this motion. After the first big roll we checked to see everyone was OK and they were.
Just now the pressure is rising, the wind is dropping and the optimists among us are sure the waves are reducing in size too. We are quite close to the new station so with any luck CTDs will recommence in a few hours. Meanwhile, we have made the most of the break to catch up with analysing samples and working on the data.
I’ve had another project to keep me busy today. On this cruise a small group of us are taking every opportunity to film the work and life on the ship, with the aim of making one or two short films for introducing people to the science we do. We are novice film-makers and I am the first to admit that it is still a skill that I need to work on. Today I have been trying to film the exciting weather, and it is proving to be harder (and colder and wetter) than I expected. I’ve been experimenting with using the tripod and using my sea legs to film the waves, but in either case they dont look nearly as dramatic on screen as in real life. I have managed to capture some reasonable clips but in the process got soaked by spray twice and now have sea salt all over my cameras. I have sacrificed my comfort (but not my safety) and a pair of pyjamas (soft cotton for cleaning the cameras) and I hope it is worth it in the end.
Images: ocean waves in 40 knot winds, including the moment I got soaked for the second time.