re-sized ITCZ

Anne’s nearing mid-way but still in the Doldrums

“A hobby a day keeps the doldrums away…”

This hasn’t been quite true for Anne Quéméré. Although nearly halfway through her epic voyage, she is still in the Doldrums but definitely figuratively not literally – her news is upbeat and positive although finishing her last piece of fresh food – an apple, was a sad moment!

“There’s no doubt that the idea of getting closer to the midway point helps me cope. While looking at the map and considering the distance travelled, it’s a bit of a victory!”

Ever since being in the Doldrums she has had non-stop rain though fortunately these storms have been accompanied by strong southerly winds which she has been able to take advantage of.

So what exactly are these fabled Doldrums?

The Doldrums, also known as the Intertropical Convergence Zone (ITCZ), is the low-pressure area around the equator where the prevailing winds are calm. The low pressure is caused by the heat at the equator, which makes the air rise and travel north and south high in the atmosphere. It is drawn into the intertropical convergence zone by the action of the Hadley cell, a macroscale atmospheric feature which is part of the Earth’s heat and moisture distribution system. It is transported aloft by the convective activity of thunderstorms; regions in the intertropical convergence zone receive rain over 200 days in a year. It subsides again in the horse latitudes. Some of that air returns to the doldrums through the trade winds.

This is a real learning curving… so what are the horse latitudes?

These are subtropic latitudes between 30 and 35 degrees both north and south. This region, under a ridge of high pressure called the subtropical ridge, is an area which receives little precipitation and has variable winds mixed with calm.

Now this is an interesting little piece of history. Why the name horse latitudes?

The name supposedly originates from the days when Spanish sailing vessels transported horses to the West Indies. Ships would often become becalmed in mid-ocean in this latitude, thus severely prolonging the voyage; the resulting water shortages would make it necessary for crews to throw their horses overboard.

Gruesome isn’t it. Poor horses… perhaps the relic of that piece of history are angry wave caps being called “white horses”… what do you think?! Stretching it a little perhaps?!

Anyways, back to Anne Quéméré.

“Here, its always the same solitude: no cargos in sight and no sails heading South. My radar is working constantly, especially at night when I sleep. On certain days, I’m so tired, a herd of wild cargoes could cross my route and I wouldn’t even notice it,” she says.

“I’ve resumed my exercises,” she continues, “and not without pain as the kite can’t seem to settle itself in the proper window and I have to manoeuvre considerably to avoid it dropping in the water. It doesn’t always work and thank God I’m alone because my remarks would scandalize more than a few with some of my foul language!”

She is hoping that a little more than 4° Longitude and she should start seeing some sunshine. That means, in the best of conditions, another 5 days if the wind holds.

Lines of longitude appear curved in this projection, but are actually halves of great circles.

It’s a real feat what Anne is accomplishing, and fascinating following her progress. Let those winds blow steadily…

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