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Trade wind user manual

With the exception of Italian Alessandro di Benedetto, all of the solo sailors have crossed the doldrums and are sailing in the south east trade winds around the St Helena anticyclone.

While these winds are meant to blow reliably they have not been strong enough, or from the right direction, to please the skippers.

The Earth turns around the sun every 365 days and around itself every 24 hours. By spinning on its axis the earth carries with it the protective layer of atmosphere that separates us from outer space. As the poles of the earth are cold and the equatorial zones hot there is continual exchange of air between them as the earth seeks equilibrium. This redistribution takes place by way of cells of high and low pressures zones that are turned by the coriolis effect, resulting in the trade winds that encircle the high pressure zones in the North and South Atlantic.


Wind that is more or less stable.

These two complementary anticyclones, the Azores High in the North Atlantic and the St Helena High in the South Atlantic, regulate weather and temperature over a great portion of our globe.  In summer, the Azores high can drift north towards Ireland and favours a more southerly position by the Canary Islands during the winter months. The curving wind turns clockwise around the high, creating northeasterlies by the Cape Verde Islands that bend to become pure easterlies by the Caribbean islands. In the southern hemisphere the winds turn the other way around the high pressure, with southerlies by the southern African coast, southeasterlies by the equator and northeasterlies by the Brazilian coast. The Doldrums is the unstable result of these two systems, turning like intermeshed cogs, that send converging winds along the equator from Africa to the Latin American coast.

Once through the unstable Doldrums, or the Inter-Tropical Convergence Zone to give it its official name, the solo sailors enter the southeasterly trade winds as they pass from the equator to shave the Brazilian coast. However the story of the turning winds is not so simple, as the wind direction and strength depends entirely on the position of the anticyclone which can often be disturbed by strong depressions born in the Rio de la Plata or the Southern Ocean. Currently the St Helena is abnormally north in position and weak in strength. Its current form is creating winds in an unfavorable direction for the struggling solo sailors, with more south than expected at the equator turning to southeasterlies by Recife (Northern point of Brazil) before finally turning north east by Rio de Janeiro.

Facing headwinds, the solo sailors must slowly follow shifty wind around the curve of the high pressure zone. Having to sail closer to the wind than normal, the sailors are making slow progress south, averaging approximately 11 knots, and will have to wait until the latitude of Salvador de Bahia to accelerate. The leaders should thus be able to hoist their bigger reaching sails this weekend in order to finally slide under spinnakers into the Roaring Forties. The turbulent winds appears to be limiting strategic options and as everyone will have to follow the leader, Armel Le Cléac’h should be able to extend his lead.




Weather forecast:
Forecast for Sunday 25th November at 11H: The anticyclone St Helene is close to South Africa and the trade winds will moderate for the leaders. The sailors will have to head south until approximately 23°S in order to find favourable winds that will carry them into the Indian Ocean.


Ranking Friday 23 November at 12h
1-Armel Le Cléac’h (Banque Populaire) à 20 643,6 miles still to sail
2-François Gabart (Macif) à 48,5 miles to leader
3-Vincent Riou (PRB) à 65,5 miles
4-Jean Pierre Dick (Virbac Paprec 3) à 82,5 miles
5-Bernard Stamm (Cheminées Poujoulat) à 87,5 miles

The fourteen sailors still at sea:
Arnaud Boissières (Akena vérandas)
Bertrand de Broc (Votre nom autour du monde avec EDM Projets)
Tanguy de Lamotte (Initiatives-cœur)
Alessandro di Benedetto (Team Plastique)
Jean-Pierre Dick (Virbac Paprec 3)
François Gabart (Macif)
Mike Golding (Gamesa)
Jean Le Cam (SynerCiel)
Armel Le Cléac’h (Banque Populaire)
Vincent Riou (PRB)
Javier Sanso (Acconia 100% EcoPowered)
Bernard Stamm (Cheminées Poujoulat)
Alex Thomson (Hugo Boss)
Dominique Wavre (Mirabaud)



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