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Negotiating the downwind slide The top three skippers are separated by a bee's dick after sailing more than half-way around the world. Now some clever positioning by leader Michael Desjoyeax could buy some time ahead of his opponents ... but what about that power failure on board his yacht? January 3, 2001 It seems the winner of this Vendee Globe will be decided in the Bay of Biscay! What with the competition as it stands mor than half way around the world, there's even money on Desjoyeaux (PRB), Jourdain (SILL) and MacArthur (Kingfisher) - now separated by less than 200 miles. MacArthur and Jourdain are so close that they could talk via hand-held VHS if the waves weren't so big as to knock out reception! The only thing likely to take these three out of a podium finish is gear failure and right now Desjoyeaux is finding life miserable without his generator. Solar panels aren't much chop deep in the cloudy Southern Ocean - despite a twilight that never stops. So he is relying totally on his wind generator for power. Considering the massive consumption these modern Open 60s demand - autopilot, communications, desalinators and more - Desjoyeaux is going to tire over the next few weeks as he hand steers more often, and sacrifices internet access, and vital weather data, to save precious power on board. In the meantime, he has positioned himself brilliantly to take advantage of following winds for the next 48 hours - provided the forecasting models are accurate! The main player is a large low, centred about 60 degrees south by 160 west, and elongating like cucumber towards Cape Horn. By December 5 the models predict this 'cucumber' to extend further, with a deeper low forming at the eastern edge of this band of low pressure. The result is a long fetch of west winds and squalls and Desjoyeaux is in amongst it, right now! He may well be able to surf downwind in consistent conditions until just before the horn, when that deepening low way off to the east creates havoc. But we're getting way ahead of ourselves here! For Ellen MacArthur and Roland Jourdain, meanwhile, things are not so rosy. Both dived south-east to take advantage of tail winds circling off a that slow-moving low we discussed last week. In fact the synoptic situation under Australia and New Zealand was so constipated over Christmas and New Year that the leading skippers sailed right over the top of it, latching onto north west winds east of its centre and surfing for miles at a time. But surfing, like the adrenalin rush, is a short lived pleasure and now the pair find themselves well south, in iceberg territory east of Ross Sea and have sailed beyond the zone of favourable west winds. Ouch! To rectify the situation both skippers need to sail north again, to reach the band of consistent westerlies now benefiting Desjoyeaux. The extra miles forfeited should make Desjoyeaux's fall from leadership unlikely for the moment. To make matters worse for MacArthur and Jourdain, Marc Thiercelin (Active Wear) is already in the correct position, to the north, and while he lies almost 300 miles behind, there is every chance he could gain on this pair if he sticks to his course. Close racing or what!
Southern Ocean pressure This forecasted pressure chart shows an elongated blob of low pressure (blue-green in colour) extending from north of the Ross Sea all the way to Tierra Del Fuego. The westerly winds lie to its north. Southern
Ocean jet stream
Note how the jet stream sweeps north below New Zealand, curves to meet another stream coming from the north west - probably originating in the coral sea before sweeping gently to the south east. to the south of this gentle sweep lies the elongated low pressure cell. Now notice how the stream arcs sharply north then south again in the vicinity of Pitcairn Island - well west of South America. This is a good example of how systems can stall: They get trapped underneath the jet stream's convoluted path. This chart helps to explain why the elongated low in the vicinity of the Vendee Globe fleet might stay put and develop through January 5, as predicted above. December 29, 1800 gmt Now this is a convoluted jet stream! This flow from Antarctica north to the Tasman sea helped eliminate more than a quarter of the Sydney to Hobart fleet, and even affected cricket in New Zealand! Fleet positions The three leaders are navigating around a near-stationary low south east of New Zealand. Desjoyeaux, in red, is best positioned to surf following winds, while MacArthur (light blue) and Jourdain (dark blue very near MacArthur's track) have sailed too far south and now have to sail north again to stay within the best wind flow. The extra miles sailed by these two will help Desjoyeaux, and may assist Thiercelin, currently in fourth place. Picture courtesy of Virtual Spectator.
More great reading: Vendee Globe Race headquarters Ellen MacArthur
(Kingfisher)
: Here's how she described conditions as of
January 2: The weather ahead is looking quite complicated with a strange -
2-phase of low's, more what I would have expected to see around the Kerguelens.
It's certainly not text-book weather down here - but then what did we expect.
Every few minutes the Roland Jourdain's home page Here's some comment from January 2: "The water temperature has shot down fast could be in danger of seeing some more white rocks (icebergs!) in this area, and so the radar is on all the time. As for New Year, I was upwind bashing through a low pressure system, and snatched a few moments of calm to wolf down some foie gras whilst being thrown around inside the boat! I don¹t know when we'll actually get to experience the great swell, which characterises the Southern Ocean, with a strong 50 knot blow. My friend Ellen is very near, we've been almost inseparable since the Transat in June I'm a woman's man, that¹s for sure! I'm not reacting to it right away. I don¹t expect anything less of her, she's brilliant, a star as long as she stays right behind me!" Re-live the Sydney to Hobart yacht race! Break ice in the Ross Sea! |