The Southern Ocean is doing a U-turn, at least for the group of leaders. After weeks of being battered by relentless low pressure systems, conditions have eased since the top 10 skippers passed the second major cape, Cape Leeuwin. A high pressure system has slowly accompanied them eastwards, on the south side of which they are currently sailing, accompanied by moderate winds from the west to north-west.
Everything is peaceful, everything is fine - actually.
The calmer conditions will seem like a relief to the competitors, a welcome chance to get some rest, check the boat and do any repairs that need to be done. However, they are now facing a new, different kind of stress. The coming days will demand a series of difficult and momentous strategic decisions from the sailors.
Let's first take a look at the high pressure system in which the fleet is sailing. This high pressure system is currently 200 nautical miles north of leader Yannick Bestaven on "Maître Coq". There is a narrow gap of around 150 nautical miles between this high and the Antarctic Exclusion Zone (AEZ), which allows the leader to make progress with decent winds from the west. But it won't stay that way for long.
This is because the high pressure zone is shifting very slowly to the south-east, directly into the path of the peloton. A nice surprise! The core will be at the latitude of the ice edge on 24 December.
Between 24 and 26 December, the high begins to change shape as it is compressed by the other systems in the area. It becomes elongated and forms a trough that is orientated from the north-east to the south-west and acts as a "wall" of light wind that blocks the route to the east.
Navigating this situation is quite complicated and we will look at some options to overcome this scenario. First of all, it looks like the three best placed boats - "Maître Coq", "Apivia" and "LinkedOut" - have decided to cheat their way south of the high to get to its eastern side. It's a risky plan: "Win or Swim", victory or demise. If they succeed, they will not only stay on the shortest route, but will also benefit from good half-wind conditions, which are perfect for foilers.
However, if the leading trio moves too slowly, it will be swallowed up by the core of the high - and possibly for a long time, as it moves in a similar direction. Finding fresh wind could then become a waiting game.
There is no chance for the immediate chasing group, which includes Boris Herrmann, to pass under the high. They have therefore been following a more northerly route since yesterday, passing above. This course choice is somewhat safer as it does not lead through larger areas with extremely light winds. However, it does bring upwind conditions, which is not really a paradigm for Imocas, which is optimised for half and space winds. Nevertheless, this option can be advantageous - if the top 3 in the south are not fast enough to escape the light winds.
It may sound crazy, but on Christmas Day it looks as if the leading group will be sailing close to the wind, with a good 4 Beaufort. Not the most comfortable course, but certainly calmer than having to fight a full-blown low. There's even time to celebrate the festive season on board.
After that, the skippers have two tactical options: Either they head further north in search of another weather system, or they stay close to the ice edge, continue to fight against the wind there and benefit from the shorter route to the east until they too get fresh wind.
Keeping further north seems to be a risky option, not only because of the many extra miles. In the worst-case scenario, there are no better conditions there either. It is therefore conceivable that the chasing pack will split up: Jean Le Cam and Benjamin Dutreux may prefer to stay to the south with their conventional boats without hydrofoils, as they are better suited to these VMG conditions on the wind. The foilers are likely to favour the northern option as they will be better able to exploit their speed potential there, provided the breeze is fresher.
It will seem very strange to see the leaders sailing against the wind in the coming days - for the first time since entering the Southern Ocean. It won't be until around 27 December that a low moving in from the northwest will finally push the high pressure system out of the way. The fleet will be able to attach itself to its rear and return to a scenario typical of the Southern Ocean.
On 30 December, they approach Nemo Point, the furthest point on Earth from land. They can go into the New Year knowing that they are probably the most isolated people on the planet. What will the ranking look like by then? That's still very difficult to predict today. There are some indications that the top group will be even closer together. Only Yannick Bestaven, the current leader, has a theoretical chance of pulling away. So it will remain very, very exciting over the holidays!
Jochen Rieker
Herausgeber YACHT
