May 02 - AMT 14
Date: 2nd May 2004
Noon Position: lat 40 41.4 S, long 41 03.9 W (797 nautical miles from Montevideo)
Distance travelled since Immingham: 26088 nautical miles
Distance travelled since Stanley: 964 nautical miles
Air temperature: 17.2°C
Sea temperature: 15.0°C
The JCR this Week.
Back in Stanley after our final calls to KEP and Bird Island we tied up at FIPASS alongside the Ernest Shackleton. The heavy plant vehicles and containers we were carrying on behalf of the building group AWG were discharged and the ship was loaded with equipment more familiar to us. Preparation began in earnest for the northbound AMT cruise, with a little break in the middle for a retirement party for BAS's longest serving employee, Miriam Booth.
From this to.....
The aft deck is loaded with science equipment. Click to enlarge.
The Ernest Shackleton set sail at the weekend, heading for home, followed a few days later by us. We will follow very different routes home, the Shackleton hugging the coasts, taking the "tourist route", while we are headed into the mid-Atlantic, in the name of science.
Science Bit In The Middle: AMT 14.
We are, once again, studying the deep ocean as part of a long- term science project called AMT or Atlantic Meridional Transect. This is cruise number 14, involving scientists from Plymouth Marine Laboratory, Southampton Oceanography Centre, the University of East Anglia , the University of Liverpool and the University of Newcastle-upon-Tyne. They are bio-oceanographers, geochemists, biophysicists and atmospheric chemists, all working individually on their own projects whilst also contributing to the overall AMT project.
The route we will follow is essentially the same on every AMT cruise. It takes us up the middle of the Atlantic Ocean, through different currents and areas of interest. The areas of the ocean shown dark blue/ purple are areas where there is not much life. These are known as gyres and are the oceanic equivalents of deserts. The gyres have a low productivity, that is there is not enough turn-over of nutrients to support much of the most basic unit of life, the phytoplankton. These tiny creatures are the bottom of the food chain, without which other forms of life would not survive . In spite of their barren nature, the gyres are of great importance, as they are vast and exert an influence on the climate on a global scale. They also act as a "sink" for carbon dioxide, absorbing it from the atmosphere, and as a habitat for bacteria which have the ability to "fix" nitrogen from the atmosphere. The importance of this will become clear in next week's diary.
The lighter orange/ red areas near the coast are areas abundant in phytoplankton and therefore life of all kinds. Some of these areas extend out beyond the coast where the continent shelves. One such area can be seen off the coast of West Africa; as the deep water of the ocean hits the continental shelf it rises up to mix with shallower water being driven offshore by currents and wind. This process creates a very rich environment for life, in complete contrast to the gyres. These areas of high productivity are known as upwellings and are of great importance ecologically due to the abundance of life of every kind.
The cruise track map also shows a light yellow area in the North Atlantic, extending from Canada across to the UK. This is an area of high productivity, where the phytoplankton are blooming as the northern hemisphere's spring warms the water. An advantage of the JCR's programme is that she sails south from the northern autumn into the southern spring at the start of the season and reverses the process at the end of the season. The scientists can thus study the Atlantic as it changes through the seasons and in particular, through the important blooming and dying cycles of spring and autumn.
The AMT cruises are part of a long term project. They comprise many individual studies all of which add information in specialist areas as well as contributing to the creation of an overview of the ecosystem of the Atlantic Ocean, its changes over the seasons and over the course of time. Importantly, these changes may help construct computer models of the ocean's changes which in turn may help predict future developments. The vastness of these oceanic systems, their interaction with the atmosphere and the climate make them an important link in climate control.
Setting up the equipment prior to sailing. Click to enlarge.
Dave Peck and friends.
Paul Hampton and Andrew Harvey.
What we will be doing for the next 5 weeks: CTDs. Click to enlarge.
Tugs and Kevin,
Waiting for the CTD to come
A day in the life of the bridge team
This week I have resumed my undercover operations and been keeping watch on the bridge with Dave, the 2nd mate. The bridge watch keepers are part of the deck department which comprises the Captain, otherwise known as the Old Man, the Mates (1st, 2nd and 3rd Officers), the Bosun, the Bosun's Mate and the ABs or Able-Bodied Seamen.
The Deck Officers:
The Captain, Jerry Burgan, is in overall charge of the ship. He is responsible for the safety of all on board as well as making decisions about where the ship goes, and overseeing the work of the bridge officers.
The 1st or Chief Officer, commonly known as "the Mate" is responsible for overseeing the Bosun and his team. He is also in charge of cargo operations and spends his days making sure the right containers are going to the right places and that the relevant bits of paper are going with them. Amongst other things, he also organizes the weekly drills, supervises science operations on deck and keeps watch on the bridge between the hours of 4 and 8 . In the days before GPS (the Global Positioning System) the Mate would take early morning sights with the sextant, using the stars.
The 2nd Officer, or 2nd Mate, is the ship's Navigation Officer. He is responsible for keeping the charts up to date, plotting our course and most recently implementing the new ship's security code. In the old days the 2nd Mate used to take noon sights with a sextant to plot a daily midday position. Now it is done by GPS, but remains the 2nd Mate's responsibility. His watches are 12 noon to 4pm and 12 midnight to 4am.
The 3rd Officer (3rd Mate) is the most junior of the watch officers and keeps the more sociable 8 to 12 watch, in theory so that the Captain can keep a close eye on him/ her without too much disruption to his own schedule. The 3rd Mate also has the task of keeping the ship's boats and safety equipment in order and can often be seen in the afternoons, checking fire hoses or running motors on deck to keep everything in perfect working order.
The 3 Mates keep the watches on the bridge, along with 3 of the ABs who act as look-outs. The ABs take turns to do each of the watches, rotating through the 12 to 4, 4 to 8 and 8 to 12 before going onto a week of nights and then a week of days. The Mates keep the same watch throughout the whole trip.
The day on the bridge:
Midnight: Dave and Kev start their watch. This is possibly one of the busiest times as AMT science starts long before dawn. We start the first CTD station at 2am and Dave has to bring the ship into position and keep her stationary while Kev goes out onto deck to help with the deck work.
4am: Dave and Kev hand-over to Andy, the Mate, and Martin. They have the dawn watch, a relic of the old days when the Mate used to take a sight just before the sun rose. At 8 they hand-over to Jo and George, who start their watch while the Mate begins his day's administration.
10am: Dave begins his day duties of chart corrections, course planning, rat catching (although he's a bit scared of this), organizing the stationary and the mail and of course acting as security officer.
12 midday: Dave and Kev resume the watch, while Jo starts her day duties and the Mate turns in for an afternoon sleep.
4pm: Andy starts his watch, while Dave does a final hours work before dinner and bed. Jo in the meantime retires to sleep until her watch begins again at 8.
8pm: Jo and Martin begin the final watch of the day.
There are a lot of people in the deck department, so we will leave the rest of the team- the Bosun, Bosun's mate and the ABs to next week.
A final thought ...
As we say good-bye to Stanley for the season, there are few places more important to us than the post office, both for receiving sending mail, and the office from where Pauline and Miriam sort out our every need.
Our link to home: Stanley post office.
The BAS Stanley office, home from home.
Next week....... the Tropics and more science...