24 Dec - Arrival at Halley
RRS Ernest Shackleton Diary
Position @ 1200 UTC - 3 hours:
75°28' South. 026°39' West. At, Creek 4 on the Brunt Ice Shelf, Halley.
Total Distance Sailed: 12187.7 nautical miles (Since departing Hull, England on 19 October 2000).
Current weather: Overcast but bright and a very very white Christmas!
Wind: Easterly Force 3.
Barometric pressure: 1002.5 hp/mb.
Sea state: Nil.
Air temperature: -2.6°C.
Sea temperature: -1.2°C.
Merry Christmas One and All
'Christmas is a time for fun, frolics and frivolities'. And even here in the lower regions of the globe, RRS Ernest Shackleton is 'getting in on the act' with our very own winter board game. 'Monotony' - or is that 'Monopoly ???.
THE RULES OF THE GAME.
Very simply, each player chooses a playing piece 'Sno-cat 17' or 'Sno-cat 14' and proceeds across the board taking drums of avtur (aviation) fuel as they go. When they reach the far end of the board you get 200 points for depositing your cargo and off you go again. At the far end of the board is Halley (The 'Mayfair') of the game, but beware that you don't get the dreaded 'Go Immediately to Jail' card - ie: Do not pass Go, do not collect 200 points, and miss a turn until you lose or obtain a Get Out of BAS Free card !
A player may enhance his chances of winning by building Hotels along the drumline as he goes. (Employees of Trusthouse Forte, Little Chef and Days Inn may not play). Players should attempt to get a full set of the utilities such as 'Fuel Dump' and 'Caboose' in order to maximise their revenue, and cheating (going away with an empty sledge) is definitely NOT permitted. The winner is the first player to deposit all their cargo, and get back to the starting place (the ship) with lots of bars of chocolate!!!
This week finds RRS Ernest Shackleton alongside the fast ice edge off Creek 4 on the Brunt Ice Shelf, Halley. Here we have started to play an extended version of the Antarctic Board Game, and the Halley relief is progressing apace. We are all very pleased with our passage down to Halley and the progress of the relief, but it has not been an uneventful week.
Last Sunday we were all at sea and still on passage from our last port-of-call, Bird Island. The day was overcast and miserable, and due to a southeasterly short and steep swell, the day onboard was uncomfortable and so very quiet. The afternoon matinee was 'Lawrence of Antarctica...' whoops, sorry, Captain Lawrence !... I mean 'Lawrence of Arabia,' which at 267 minutes long, or thereabouts, had people falling asleep half way through. Indeed, when after 2 hours, the word INTERMISSION came upon the screen, it had us worried that the movie might not finish before we reached Halley !!. The 'Halley Sweepstake' was still running and it was anyone's guess as to the actual arrival time alongside Creek 4. But we were well prepared, and all preparations for cargo work and personnel transfers were fully discussed on our daily HF radio schedule with Halley.
Monday was a better day for being at sea. The swell had died down considerably just in time for the very full schedule of events that were to start this week. Prior to arrival at Halley, each and every FID would undergo a final preparation of body and soul just like 'Caine' in 'Kung Fu'. But they were not anticipating 'walking on ricepaper', nor 'branding themselves with a boiling hot cauldron of coals', but with a very varied scattering of subject matter that would enhance the training already received back in Cambridge and the UK.
Given the full five day schedule for the additional training the FIDs received it is easy to imagine our FIDs had embarked upon a Summer School. One class in particular was Jo Arendt's Chronobiology talk in the Mess, and here to tell you all about it is Jo herself :-
The 24 hour day within us: Halley medical research
Josephine Arendt, PhD, FRCPath, Professor of Endocrinology
University of Surrey
Guildford, GU2 5XH
Humans are diurnal creatures. Our physiology, if not necessarily our behaviour, is geared to sleeping at night and being active during the day. Observation of almost any of our body functions reinforces this statement. On a daily basis our hormones, blood pressure, urine flow, immune system, perception of pain, and many others, rise and fall in strict relationship to each other and to the time of day, in a person who is normally synchronised to the environment. We feel most sleepy and least alert at night, and our ability to perform different tasks is at a minimum. However recent cultural developments mean that many of us have to behave (usually intermittently) as though we were nocturnal (24 hour shopping, banking, emergency services, Halley Relief, etc). Our internal clock, which drives our internal daily rhythms, usually either moves to night shift mode slowly or not at all. This means that we are trying to work and sleep at times when our body is programmed to do the opposite. The major peak in road accidents occurs between 2 am and 5 am, associated with the low point of our core body temperature and alertness together with the peak of sleepiness and the 'darkness hormone' melatonin. Many of the major industrial accidents of our time have happened during the night shift, for example Chernobyl, Three Mile Island and Bhopal. We need to understand the time dependent nature of our physiology and how to control it.
Halley - a model environment for clinical studies
Halley is a wonderful site for such basic research for several reasons. Principal amongst these is the presence, for more than a year and sometimes longer, of a group of young healthy people, living in the same environmental conditions and eating more or less the same food: a controlled population for clinical studies, the like of which would be hard to find elsewhere. The station doctor carries out the research - they are present and have immediate access to their subjects throughout the year. Each person carries out at least one period of night shift work (firewatch) during the year. Unusually, at Halley people adapt their rhythms completely to night shift within a week - and have more problems adapting back to day shift, especially in winter (work of Mark Midwinter and Jonathan Ross). We believe that this is due to the lack of conflicting social and environmental time cues. We have made similar observations on a North Sea oil rig (Tern Alpha) with a similar type of shift schedule. It is probably undesirable that people working intermittent short-term night shifts (e.g. three-day rotations, early, late, nights, rest) should try to adapt. Rather they should take short term measures to maintain night shift alertness and performance and good daytime sleep duration and quality. However if they adapt to night shift naturally, it makes sense to speed this process up and also to help the subsequent readaptation to dayshift. To this end research at Halley has pioneered strategies for shifting the internal clock.
Shifting the internal clock with light: winter sundown and firewatch
The light environment on Halley, where the sun does not rise for three months in the winter, permits experiments to study the importance of light in basic human physiology. Studies carried out in 1984-5 showed, we believe for the first time, that timed exposure to short bright white light pulses each day in the winter would change the timing of our internal daily rhythms (work of James Broadway). Extending this observation we found that timed light pulses could hasten a return to dayshift mode after firewatch in winter. Numerous research papers now describe the usefulness of bright light, not only to shift rhythms but immediately to improve night shift alertness. During Halley relief, which is taking place at the moment, people work 12 hour shifts, either nights or days. The nightshift is of course in continuous daylight so it will be interesting to study adaptation in these conditions. At the very least the strong light should maintain alertness and probably induce rapid adaptation.
Night shift meals: how to reduce blood lipid?
Another aspect of night shift work is possible susceptibility to chronic disease. For example heart disease is more common in this group. In simulation experiments at Surrey we have found that blood lipid is usually higher after a nighttime meal compared to after the same meal during the day. High blood lipid is associated with increased risk of heart disease. Depending on the contents of the meal, glucose and insulin may also be higher at night- it is likely that this predisposes also to heart disease and possibly diabetes. Recently, at Halley, Jon Lund, the doctor, showed, for the first time we believe, that these changes occur in real shift workers. Our current projects in this area include attempted modification (reduction) of blood lipid at night by bright white light treatment (Jonathan Paddle, data currently being analysed), comparing blood lipid after day and night meals without standardising the meal, and keeping a nutrition record to help interpret the results (Lil Ng, study just finishing).
How to keep optimal body clock time: lessons from Halley
In our experiments at the University of Surrey we find that domestic intensity white light for 12 hours every day is not sufficient to maintain 'synchrony' of our internal clocks with the 24 hour day, without other strong time cues. People then get up and go to bed later and later, delaying their sleep each day by as much as an hour, but on average by about 20 minutes (a number of people have been doing this on RRS Ernest Shackleton during the voyage down). The amount of this daily delay is a function of our 'clock' genes. At old Halley, light exposure during the winter sundown is mainly from internal lighting and normally we would expect people to desynchronise, in this way, from external clock time. This has clearly been shown by Australian scientists during sundown on the (now non-existent) Greenpeace Base, which had if anything more light than Halley. However the vast majority of Halley personnel remained synchronised in our studies (work of James Broadway, Paul Griffiths, Mark Midwinter, Jeremy Owens, Ian Makkison, Rory O'Conor). We believe, but we do not know for sure, that this is due to the structured daily activity on Halley, which contrasts with only a 24 hour radio watch on the Greenpeace Base.
Desychrony is a problem in normal life. Our time cues have become more and more chaotic since the invention of artificial light. Many office workers never see natural sunlight in the winter. One of the probable (but speculative) consequences is the prevalence of rhythm-related sleep disorders. We need to define the factors that maintain the Halley personnel on a 24 hour day, since this knowledge will be of benefit to any urban population in high latitudes. To this end, this coming year Tom Rieley will measure activity-rest and white light exposure in volunteers throughout the year, and relate the results to their sleep timing and quality. Cambridge Neurotechnology have generously provided wrist-worn monitors to automatically accumulate data, both light and activity.
Human clock genes: can we relate them to behaviour in a low light environment
Finally the susceptibility to desynchronise from the 24 hour day, and a related phenomenon, the speed and direction the internal clock adapts to night shift, are probably related to different variants of human clock genes. We shall evaluate both on Halley using the marker rhythm of melatonin (measured via a urinary metabolite) to define the phase of the clock with some precision. Subsequently we will look for associations with variants of known clock genes. It may be possible one day, using genetic information, to advise people whether or not they will find specific shift schedules easier to cope with than others - and even what time of the day they should take exams or their driving test.
Author : Prof. Jo Arendt
The most surprising aspect of the passage south this year, was the lack of sea ice we encountered. Using sophisticated satellite imaging equipment (High Resolution Picture Transfer) (see ES diary 17 December 2000) we were able to estimate the very best track into Halley to avoid the worst of the sea ice. In conjunction with some science that the ship was to undertake, this route took us from the longitudes of South Georgia eastwards to 003° West, before turning back southwestwards towards Halley. The track proved to be very good and we encountered very little pack for the majority of our passage. This is borne out by the sentiment of the Third Officer who was getting bored on watch because there wasn't any ice to crack... But, on Monday, he was far from bored as a mist and reduced visibility in snow flurries kept him on his toes. There were occasional stretches of pack to be seen, but apart from four hours of ice breaking on Thursday, these were intermittent and short-lived. The majority was open water and 12 knots all the way. On Tuesday we had reports that the German Icebreaker RV Polar Stern had cracked through to Neumayer - north of Halley, and she had only encountered fast ice for the last 10 nautical miles of her passage.
But this was not merely a transit from South Georgia to Halley, because the ship was engaged in science for most of the time. There was the continuation of the STCM (magnetometer) logging to 'fill in' some of the blank spaces in the magnetic charts of the area, and then a programme using Expendable Bathythermographs (XBTs) which extended our time-on-passage, as we had to slow right down at three-hourly intervals to allow a sensor to be dropped over the ship's side. The XBT sensor feeds back temperature data to the ship as gravity pulls the probe down to the depths. These data are then compiled and transmitted back to the UK by satellite communications. For full details of XBT's, polynyas and the science involved, please refer to last season's diary (ES Diary 12 December 1999).
By Thursday 21 December it was becoming apparent that our estimated time of arrival was going to be Friday around 10.00 am. There was always the possibility of last minute ice to contend with, but tentative ETA's were passed to Halley on the assumption that the 'open water' would last all the way to the Brunt Ice Shelf. We passed by large icebergs and icefloes on the last day into Halley, but nevertheless, the water remained open and we finally arrived alongside at 0830 hours. Chris 'Chicago' Littlehales was the winner of the sweepstake having guessed an 08.00 am arrival. Well done 'Chicago'.
The rest of Friday was given over to simply tying up alongside the fast ice, unloading the vehicles from the helideck, and exchanging greetings with Halley personnel who had travelled down to welcome us. By lunchtime we were secure alongside and by 2000 hours, the ship was awaiting the arrival of the last of the Halley personnel who could get away for a festive evening of Christmas carols on deck. Mince pies and a very warming cup of 'mulled wine' to wash it all down added the necessary spice to the event. It was most surreal to be standing on the cargo hatch with a mince pie in one hand and carol sheet in the other announcing the anniversary of Christ's birthday by a slightly off-key rendition of Silent Night, Holy Night in 24-hour daylight. Surreal, but nice. It was 'hats off' to Alex Gaffikin, who provided the carol sheets, typed by her own fair hand from memory at Halley. Well done, Alex.
Click on the images for a Surreal Carol Concert.
Saturday saw the work begin in earnest. At 0800 on Christmas Eve, the first shift of the two shift system swung into action to start the unloading of 1750 drums of Avtur, steel leg-extension material, complete steel fabrications for a clean air laboratory, and numerous containers, boxes, bundles and crates of cargo. The full details of which will be available next week after the operations are complete. But onboard, the shifts are working from 0800 to 2000 and from 2000 through the night until 0800 in the morning again. Two cooks on board maintain a healthy supply of grub, sweets, and all things nice and we are not short of the occasional mince pie. Several of our FIDs have already departed the ship to take up residence on Halley for the next 2, 16, or 33 months, depending on their employment contract. Others are staying on board to help out in the hold, on decks and by the side of the ship on the sea ice. Apart from craning the cargo on and off the ship, it must all be man-handled and the Sno-cats have all to be driven, so there is no shortage of jobs for the manpower available in this big Board Game at Christmas.
Click on the images to enlarge.
Forthcoming events : Completion of cargo work at the ship's side and finishing the Halley relief. Thereafter to depart for South Georgia via more STCM transects in the north Weddell Sea.
Contributors this week : Many thanks to Professor Jo Arendt, and to this week's official web-cameraman Mark Godfrey.
Diary 11 will be written on 31 December 2000 and should be on 2 January 2001.
MAY ALL ON BOARD WISH EVERYONE AT HOME A JOYFUL NEW YEAR AND A VERY HAPPY, HEALTHY AND PROSPEROUS 2001 !