NEWSLETTER 3 DISCOVERY CRUISE 207
Since we dock in Port Louis Mauritius exactly three weeks today, today's newsletter finds us exactly at the mid-point of our cruise with the bulk of the work in our main working area [the Crozet- Kerguelen Gap] already completed, and enjoying a long sunny and increasingly calm steam south to the ice-edge. So it gives me a good chance to catch you all up with our news and doings.Which have been considerable. We've had our triumphs and disappointments as on all cruises, but nothing that would prevent us carrying out our main aims as you will see.
When Newsletter Two reached you, we had just picked up the first of our current meters and were moving east, working a CTD/ freon section down the west wall of the Crozet Basin , north of Crozet Islands themselves.[2a on the attached map]. As we did so we noticed with the same uneasy feeling of deja vu the same characteristic signs of a CTD multisampler going wonky. First the bit where all the sample bottles say they've fired but you begin to suspect [ from Don and Ali's impeccable chemistry] not quite in the right places at times; then the first red misfire light which turns out to be a false alarm; then a sequence of misfire lights which really were misfires which cause you to trigger a bunch of bottles at important depths to make sure, but which begins to squander your vertical resolution; then the final stage when you get a full set of misfire lights, the bottom bottle goes off 2000 m above where you wanted it to, half the bottles come up open and you have to repeat the cast. This depressing progression---- which will be familiar stuff to avid readers of these Newsletters from last year's cruise,---- is a fair representation of events on the 6 stations of this northern line and cost us some time, some data, and [to those of us who still had some of the other sort] some grey hair.
However, cometh the hour cometh the Man. During the short run south to our main working area in the Crozet-Kerguelen Gap, [area 2b on the map], where the work would be too intensive for such shenanigans, John Smithers and Richie Phipps effected what appears to be the Miracle Cure. John drilled a lot of holes in a little plastic disc at the bottom of the beast's internal motor to let the air slosh out and the oil slosh in more effectively, while Richie noticed that the camshaft which triggers the bottles had been made with a flat on it allowing sea water to flood in past the O-seal. So for him it was the work of the instant to turn it perfectly circular on his lathe and fit an O-seal that actually did. You'll excuse me waxing over-eloquent on this subject, but it and me go back a long way together and I feel somewhat passionate about its cure.Anyway in all the many CTD's we've worked since then across the Gap, we haven't had a sample out of place.
This Crozet-Kerguelen line wasn't just for CTD of course but was also the site of our principle array of current meter moorings. From arrival on Wednesday 2 March till the late evening of the 8th, all teams of people on the Vessel ---and I don't just mean the scientists ----put in the most intensive work of the cruise, recovering moorings by day and CTD/chemistry all night until completion in the grey, lumpy and unpleasantly-marginal conditions that seem to be par for the course in this bit of the Roaring Forties. Certainly if this place has a different face, we never saw it.
Triumphs and disappointments again of course. Only deployment cruises are free from these! By the end of the line we have recovered 8 and may yet recover 9 of the 11 current-meter moorings in the north, together with the POL tide-gauge from the western end of the line.But we have certainly lost one full-depth mooring which, if we ever heard from it at all, [and that isn't certain] appeared only ephemerally and at maximum gain, suggesting it may have collapsed or partly collapsed, so that its release may be lying along the seabed, talking sideways where we can't hear it. And we have certainly lost one of our upper-bottom moorings, though we suspect its release was damaged on launch, since it was the only one which wouldn't respond to our commands last year immediately after we'd laid it, as we mentioned in last year's cruise report. And the second POL tide gauge, which has two quite different and independent release systems, never replied to either one, despite our search of a wide area, which can realistically only mean that it released itself at some time during the year and has taken off. The other full-depth mooring is the "possible 9th " I mentioned above as it is certainly in place, certainly upright and loud in its responses to every command but "cut", but we have by no means given up on it and it will be getting our full attentions when we get back from the South. Watch this space. I should be surprised if the collective cunning of Ian Waddington, John Read and Tiny the Bosun don't manage to reach conclusions with an unintelligent mooring only 300 metres down!
We already have good cause to celebrate Tiny's ingenuity with one of our successful recoveries, whose buoyancy reached the surface together but in two quite separate parts --blown apart with the shock when one of its glass spheres imploded.Since the trail line you get hold of was on the unimportant bit, we were all rather scratching our heads about how we could reasonably get hold of the half-sunk remnant bearing the rest of the mooring and four of Her Majesty's current meters, when Tiny hove in sight bearing a large wire noose on the end of a long bamboo pole and proceeded to lassoe it, promptly and without fuss.Though we knew him to be a man of the Wild West [Plymouth], I can't pretend there weren't sceptics among us, but since Tiny is twice our height, three or four times our volume and It Worked, it was as well we buttoned our lip.
Anyway, even before he brings the same ingenuity to bear on the capture of our hesitant Mooring F , we already know that the recovered records provide a nice distribution of data across the Gap to serve in explaining the deep tracer field. Its most impressive feature is the relatively strong northward boundary current against the Slope east of Crozet, more or less where the deep freon maximum passes through on its way to the Indian Ocean. With our new improved multisampler Tom and Malcolm's All Stars have been able to produce clean noise-free vertical profiles which beautifully describe the deep freon maximum.Malc wandered in bearing the first of these when things were very low after the misbehaviour of the multisampler and the loss of our first full-depth mooring, and therefore at a time when we certainly needed this boost, but even so, I think he was quite surprised that he came so close to being kissed! He was himself as pleased with the fact that this first near-perfect profile had been produced and plotted unaided by Rebecca Woodgate and Tony Child, if under his avuncular gaze. The third thing we always worry about as a touchstone of performance is the general quality of the salinity data ,as measured by the differences between the CTD data and that of the bottle samples.From present evidence, Ali Reeve is coaxing a better performance out of the salinometer than we have ever seen before, which pleases us greatly but worries Ali since she knows she's going to have to keep it up!
So there it is, the good points and the bad, but far too much of the former to be anything but pleased with our performance. Gales and swell setting in heavily while we completed the easternmost end of the Crozet-Kerguelen line suggested it was time to go South and if you check the attached map you'll see us passing Heard Island on our way to rendezvous with our 5 remaining moorings in the Princess Elizabeth Trough, and some CTD's near the ice margin for Tom while he checks-out the present-day freon loading going into the ocean. And maybe a penguin or two.
Meanwhile in case time hangs heavily on our hands after so much work, we have a full social programme. Barely recovered from the birthday festivities in honour of Jane Robertson in which a barfull of people appear to have been shaken and centrifuged into more-than-usually-high jinks by a full gale and a quartering corkscrewing sea, we have tomorrow night a slide show on Iceland by Leo the Chief Steward, and on Africa by Jackie Cooper followed by Quiz Night 2 with drinks provided by Simon Watts in honour of his birthday; at no extra charge you can enter Don Kirkwoods learn-tae-blaw-the-trumpet contest [free tuition] the prize going to the novice that can belt through " The Saints" in the most recognisable fashion and taking fewest prisoners by the time of the after-deck barbeque, though whether this be in the balmy climes of Mauritius or at the world's first Polar B-B-Q we haven't rightly determined; there appears to be something of a Scrabble Wars going on between Tom Haine and Elaine,we think in a vain attempt to divert her from trashing yet another toaster by cooking things in it; the culinary staff are themselves pulling out all the stops to divert the world-weary with one entire menu based on Orwell's Animal Farm, and later "Ostrich in a red wine sauce", to name but a few.
And of course if all else fails the unnatural motion of a ship in a full gale is itself a potent and unscripted provider of the bizarre. Don [who seems to be figuring largely in this edition] is still dining out on one extreme wave which hurled him backwards without warning off his bar stool, his elbow catching and opening the door to the library as he flew past. Though unrehearsed,he coupled a natural "ageelity" with a native canniness to conclude with a backward somersault to the far library wall and all without spilling his pint. Beat that Lillehammer!
More of these ramblings anon when we've visited the Polar Regions. Meanwhile Happy Mothers Day to all of you who are and as the rest of you ought to know without me telling you we all miss you madly as ever and and look forward most of all to any bits of your news that filter through to us. Love to all, including the boy Foggy
BOB DICKSON , PSO,
RRS DISCOVERY, OFF HEARD IS., SOUTH INDIAN OCEAN, 10 MARCH 1994.