April's shark On this April Fool's Day, tricks don't appear to be on the menu off Patagonia. Indeed the quick, radical changes in the weather conditions suggest that it's time for strategic choices right now. And though like a shark, the Americans have homed in on their prey Groupama 4 this noon on Sunday, there is likely to be a way out with the arrival of a zone of high pressure right across the route to Brazil... The climb up towards Itajai isn't going to be at all restful as the rapidly changing weather conditions along the Argentinean coast are being accompanied by the Andes cordillera phenomenon, leading to some separation between two major oceanic and climatic ensembles: the Pacific with some austral depressions, which stumble against the steep shores of Chile, and the Atlantic, which plays host to disturbances created to the South of Brazil due to the continental heat, to propel its way towards the Roaring Forties. As such there is a lot of movement in the air masses and consequently a great deal of alternation between the mini depressions, which are forming locally between Tierra del Fuego and Rio de la Plata, and the zones of high pressure which take over once these disturbances fill in and head off towards South Africa... Constantly adapting... In this way, since rounding Cape Horn on Friday at 1300 UTC, Groupama 4 has been sailing in a moderate northerly breeze (15 knots), backing round to the North-West as it builds (20 knots) with gusts, then switching temporarily round to the South-West as it drops away sharply (8 knots) before shifting round to the South-East (12 knots) then to the East... And since noon on Saturday, the breeze has continued to oscillate with a south-westerly (12 knots), building to 25 knots before easing this Sunday morning to 15 knots, and then dropping right away late morning (5 knots) as it shifts round to the South! We can well imagine that the activity on deck has been endless in order to quickly adapt the sail area. The Americans have made the most of these conditions to make up their deficit since rounding Isla de Los Estados, but although the weather conditions were fairly different, the separation in terms of distance and time remains slight. And this constant adaptation of the sail area is very unlikely to change before Brazil: the succession of climatic phenomena ahead of the duellists will call for quick reactions at all times, and doubtless some changes in hierarchy at the front of the pack in relation to the calms and the fresh breezes. Indeed, Franck Cammas and his men lost control of the fleet this Sunday morning, though the trajectories which had converged level with the Falklands have now split away again. Groupama 4 has positioned herself twenty miles to the West of Puma and though there is less wind at the end of the weekend closer to the continent, this is also the side where the fresh breeze will be the first to hit as it is shifts round to the SSW at over twenty knots. The puma of the pampas Is it because the puma is very common in Argentina, and even in the Andes cordillera up to 5,000 metres up, that the Americans have regained their agility? Indeed, Ken Read and his crew have played this ascent really well since exiting Le Maire Strait. However, it's probably at the start of the week that the duel will further intensify: there shouldn't be too much lateral separation, but there will be some micro options which will cause the situation to yo-yo... Initially, it will be necessary to sail in front of the wind, before heading offshore to benefit for as long as possible from this vein of around twenty knots of downwind conditions. A zone of high pressure will then settle in to the East of Rio de la Plata as it grows: at that point it's not going to be easy to choose the right trajectory, because near the Argentinean coast, it's a northerly headwind which will colour the start of the week. However, given that the high pressure will also distance itself from the continent, the way forward will be blocked offshore with the risk of a very big diversion to avoid falling into its centre where there won't be any wind. The first solution is the shortest but will call for a beat in strong winds. Added to that it is likely to prove a more conservative solution in the sense that the weather changes are rolling in from the West. The second solution is easier to deal with initially with some downwind conditions, but it could turn into a trap if the zone of high pressure continues to sprawl out over the coming days... Standing for the 5th leg from Auckland - Itajai 1 April 2012, 1300 UTC 1. Groupama 1,354 miles from the finish 2. Puma equal distance to the finish as Groupama 3. Telefonica 333.9 miles astern of the leader 4. Camper 1,503.0 miles astern of the leader 5. Abu Dhabi Ocean Racing 1,781.9 miles astern of the leader 6. Sanya DNF. |
Groupama | crew | Sleeps one off
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