27 Apr - Towards South Georgia
RRS James Clark Ross Diary
Noon Position: 53° 19.9 S, 43° 27.8 W)
Distance Travelled since Grimsby: 33678.5 Nautical Miles
Air temperature @ Noon today: 4.9°C
Sea temperature @ Noon today : 2.7°C
Weather: Poor, NW, 8, 970.4
Towards South Georgia
We started the week arriving in wintry Stanley on Easter Monday morning. Things were very quiet at FIPASS as everyone who was anyone in the Falkland Islands was on Victory Green in Stanley celebrating the Queen's birthday. Stanley has a parade and various military units march past, a 21 gun salute and even a fly past from the RAF based at Mount Pleasant. Two Sea Kings, a Chinook and a Tornado roared down over Stanley harbour and the JCR. Unfortunately this year there was no marching band as it is apparently in Iraq!
A short two day call was all we were allowed in Stanley and were on our way by 0730 on Wednesday morning. We welcome 16 new scientists who will be joining us for the next few weeks. We headed back into now constantly rough seas to the south of the Falklands as we slowly rocked in the general direction of South Georgia. We are completing a line of oceanographic measurements across the North Scotia Ridge (more below).
It is getting to that time again when all the crew are getting very excited. They are excited about going home as they have now done 3 ½ months of their 4 month passage. Constant discussion of their travel arrangements home continues (on the Tristar via Ascension or on Lan Chile via Santiago), have they written their hand over notes, plans for Santiago, plans for their holidays and talking about anything unrelated to the ship. They have done their time (and paid their debt to society - Ed) and they are anxious to get home. Everyone is getting a bit bored by the constant rolling around and is looking forward to getting off and having a bit of summer weather. Some of the guys have already packed all their gear ready for coming home!! I guess that Captain Burgan's crew are having the opposite thoughts right now and preparing themselves for travelling south and rejoining the good ship (see you soon guys and don't be late! - Ed). Unfortunately we'll be losing some of Captain Elliott's crew for the last time but more of that next week.
The weather continues to be poor with a large swell. Yesterday we had some big waves over the starboard side that damaged the water bottle annex. The metal roller blind was caved in by the weight of water on deck but nothing a quick bit of welding by Simon couldn't sort out.....
The rough sea is very difficult to capture on film but there are some poor attempts below that completely fail to do it any justice. Click the images to enlarge them.
David Stevens and Karen Heywood are onboard are keeping a diary of their time on the JCR. They are completing work with University of East Anglia (UEA) and so for an alternative view of 'planet JCR' please have a look at their website. For all you boffins out there it has also got lots of explanations of science and other juicy links. You'll find it at www.mth.uea.ac.uk/ocean/srp/
An odd title for an article on science but that is really what this cruise is all about. In the dark mists of the last century (1999) the JCR entertained the 'ALBATROSS' cruise. We are now finally finishing that work with a short cruise to South Georgia hence this is the 'son of albatross' (chick sounds better - Ed). (Real albatross are fascinating and beautiful birds but have absolutely nothing to do with this cruise apart from that they will accompany us during our at sea looking for food in our wake. Sorry all you bird lovers out there!)
The big question - why are we here?
Answer - to find out the influence of the Scotia Sea on global ocean circulation, or more accurately to find out the effect of the North Scotia Ridge on the Antarctic Circumpolar current.
Doesn't make sense? - OK - read on.....
The circumpolar current is a flow of water that runs west to east in a giant circle around Antarctica. See picture.
This current transfers water between the Pacific, Atlantic and Indian Oceans.
The current passes through a narrow gap called the Drake Passage (between S. America and the Antarctic Peninsula) and then passes into the Scotia Sea before being split into different directions.
The sea bed is not flat.
The ACC plays an important role in the Earth's climate system as it carries heat between the Pacific, Atlantic and Indian Oceans.
THE BIG PICTURE
Climate modelling is a highly complicated and sophisticated science but basically involves examining current oceanographic, land and atmospheric data to then predict what will happen in the future based on calculations. The greater the understanding of how the oceans work, the more accurate the future predictions will be.
FILLING IN THE GAPS
In 1999 the ALBATROSS cruise investigated the flow of the ACC into the Scotia Sea and out through its southern and eastern boundaries. This can been seen in the cruise map from 1999 as the JCR worked its way round the Scotia Sea.
As you can see there is a gap at the northern side between South Georgia and the Falkland Islands. This is the area we are filling in at the moment. It is important as it contains the North Scotia Ridge including the Shag Rock Passage which is a deep passage connecting the Scotia Sea and the Malvinas Chasm. It is an important outflow for water to the north. The aim is to find out how much water is passing through it and where it is going.
With a east-west transect running along the Scotia Ridge we can measure where the various currents (or fronts) are, their strength, and their direction. Using a large CTD device (Conductivity, Temperature and Depth) equipped with addition sensors various measurements are made. Measurements of O2 saturation, transmission of light through the water, chlorophyll and current profiles are also recorded to provide an accurate picture of water movements.
The CTD transect provides a good spatial coverage along the ridge but poor temporal information (ie it only provides information at one time point in the year). To improve temporal coverage some buoys will be deployed next week (these have poor spatial coverage as they are only in one place) but more on these next week.
Unfortunately due to the weather we had to delay the second half of the transect as we cannot use the CTD in very rough weather so hopefully we'll be back next week to finish off.
The ultimate goal is to provide greater information on the sea currents and hopefully we'll let you know how we got on next week. Karen is feverishly analysing her results as I write this........
Fashion moves on rapidly down here in the hip and trendy Scotia Sea. Last weeks haircut is already consigned to the barber's floor of history and another style has been cut in the shaving foam of time. The psychiatry referal is in the post....Does he:
a) have sympathy with badgers?
b) have an unusual form of alopecia south atlanticus?
c) need to watch our more carefully for trains?
d) have reason to sue?
e) need to get out more?
f) support Newcastle United? (Howay the Geordies - Ed)
(Hint: It is not the Doc trying to get TV reception!)
Thankyou this week: to Karen and David for the science update.
Coming up next week: shy buoys and South Georgia in the distance.........