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Tuesday, 24 May 2016

Towards the Equator

The British Admiralty reference "Ocean Passages for the World" states that [the Trade Winds] are remarkable over large areas for their persistence and steadiness.

And so it has been for us. For ten days and some 1500 nautical miles of travel towards the southwest, we have been graced with a constant twenty knots of wind from directly aft. The winds have been so constant that for six days of these ten, no action of any sort was required to sail our vessel. Certainly there was cooking and washing up, watching for traffic and interpreting the weather, but sails were not adjusted or changed in size in any way and our heading was not changed even a degree!

Our watching yielded very little: we sighted no ships and, according to our instruments, only one vessel approached within fifty miles of us [that's as far as our instruments can see]. The only visual evidence that anyone else lives on the planet has been a single airliner contrail that Mary Anne sighted a few days ago, possibly enroute from Los Angeles to Tahiti. Other than that there have been only the beautiful Tropic Birds with their spindly tail feathers and that most elegant of fliers, the Albatross.

During this transit of the northern Trade Wind belt, water temperatures, and thus air temperatures, have increased steadily from the low twenties to 29C. Even at night, it is a sweltering 32C in the cabin!

There is always SOME technical concern on a boat and this temperature rise has led to our current issue. Our battery charger has reduced its output more and more in the rising temperatures to keep from overheating. On the cloudy days [reduced solar power] this has led to longer and longer generator runs to recharge our batteries - and this while our electric consumption is increasing due to refrigeration requirements. Effort and imagination usually provide a solution ... I expect we will wire up an extra cooling fan for the charger electronics if initial efforts at improving ventilation fail.

Now, as we approach the equator, there are some subtle changes. We have sailed into the equatorial counter-current - an area just north of the equator where the ocean currents set towards the east rather than the normal trade wind current towards the west. A slight course adjustment towards the south allows us to pass this inconvenient current as quickly as possible rather than fighting it on a westerly course. There is no point in being carried towards South America for longer than necessary when your destination is Australia!

Our next milestone is the Intertropical Convergence Zone. This is the region where the Southeast Trades of the southern hemisphere and the Northeast Trades of the north converge and head upwards in a region of light winds and occasional heavy thundershowers: a kind of boundary between the weather systems of the two hemispheres. This zone moves north and south with the seasons and also on a daily basis. The latest weather guess puts it at six degrees north of the equator.

Our nearest land is now tiny Christmas Island in the island nation of Kiribati 640 nautical miles to our southwest.

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At 5/24/2016 16:09 (utc) our position was 06°51.36'N 147°55.56'W

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