Vendée Globe

As Titouan Lamazou called it, the Land of the Shadows inspires fear and fascination at the same time. This grey and desolate universe, hundreds or even thousands of miles from civilisation, you can expect to find winds, waves and maybe some ice...  

We often talk about the Great North, when talking about extremes, and by the "Great South" we are referring to that strip of ocean located below 40° south. While circling Antarctica, it is the shortest distance around the world, it also means you are in the Roaring Forties and Howling Fifties and the most treacherous conditions in the world. As there is no land, boats are not the only thing top move freely around this highway in the south.  «This region of the planet is rather special. Nothing stops the lows from circulating, while at our latitudes in Europe, the Atlantic lows hit our coast and are weakened as they reach the continent,» explained David Salas,an Antarctic climate expert at the French Weather Research Centre (CNRM).

«These lows originate in two ways,» explains Sylvain Mondon who alongside Richard Silvani is in charge of the marine forecasts for the Vendée Globe. «There are firstly those that form downwind of the neighbouring continents – South America, Africa, Australia, New Zealand and then those, less frequent, resulting from cyclones and tropical storms in the Indian and Pacific Oceans.  Between the Cape of Good Hope and Cape Horn, the competitors know that they will experience between 8 and 20 cold fronts. At this time of year (end of the spring and start of summer in the south), the westerly winds average between 20 and 25 knots gusting to between 35 and 40 knots.  Les us call them the’ normal conditions’.  The trickiest area is between the Cape of Good Hope and the Kerguelens, where you can expect to find the strongest winds and the highest waves. The lows move from west to east at a speed of around 25-30 knots, or in other words 30% faster than the boats. While a system may stay with a competitor for some time, it will end up overtaking them at some point.  Between each low, there is a variable ridge of high pressure, signifying a calm that has to be crossed, where the wind can drop off to 10-15 knots.»

The Land of the Shadows
In other circumstances, sailing downwind in 20 to 25 knots of wind would be described as ideal.  Except that here, the series of lows offer permanently grey skies.  The average temperatures ranging from 5 to 14 degrees, are reduced by the wind chill factor and the speed of the boat. Inside the Open 60’s, once past 45° south, they hover above zero. As for precipitation, it is present 3 days out of 4, and can sometimes be in the form of hail, sleet and snow. Then, there are the seas.
While nothing stops the winds, nothing stops the waves either. Jean Michel Lefevre (Météo France), in charge of wave forecasting, explains: «As this is a zone, where there are no obstacles, the waves are free to build up over extremely long distances. The fetch – the distance over which they are subject to the effect of the wind –is very long. In the southern hemisphere, the waves often reach their maximum height, there is a permanent swell.  So these are areas,  where we can expect to find heavy seas.» European observations carried out over 30 years (between 1970 and 2000), presented in the KNMI wave atlas (Dutch weather service) give an average height of 3 to 4 metres. This significant size (called H 1/3), corresponds to the average of a third of the highest waves.  It is therefore common to find waves 1.5 times or twice as big.

Cold
Consistently strong winds, heavy seas, rain, cold…
It is the cold, which is perhaps the most dangerous, as we're talking about ice.  You would not expect a round the world race (race or record in fact) during which the sailors do not spot some ice, especially as the temptation is to dive southwards to shorten the journey, as this increases the risks of encountering icebergs, which are common in the region.
For this reason, eight Ice Gates have been set up by the Vendée Globe race directors (virtual lines of latitude that the competitors have to respect), while CLS (part of the French Space Agency) is watching for big icebergs lying in the path of the sailors. «Even with Ice Gates, that does not mean to say they will not encounter any ice,» commented David Salas. «These icebergs, which break of from the Ross Banks or the Antarctic peninsula in the Weddell Sea, can be found off South Africa and in the south of the Indian Ocean. They can float all the way around the world.  In 2006, we spotted an iceberg as big as a house off New Zealand. For it to have reached that point, we reckon that originally it must have measured 8000 km²!»  But more than this type of giant, it is the growlers, those little fragments of icebergs measuring several square metres and weighing thirty or forty tonnes that the sailors fear the most…

Camille El Beze

 

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