A Note on Strategy

12 Dec

December 8, 2018

Day 65

Noon Position: 44 23S 40 47W

Course(t)/Speed(kts): ExN 6

Wind(t/tws): SSW 25 – 30

Sea(t/ft): SW 10+

Sky: Light Cumulus

10ths Cloud Cover: 6

Bar(mb): 1002, rising

Cabin Temp(f): 59

Water Temp(f): 54

Relative Humidity(%): 71

Sail: Working jib with three reefs, broad reach.

Noon-to-Noon Miles Made Good (nm): 132

Miles since departure: 8789

Avg. Miles/Day: 135

Slow bell overnight. Was feeling pretty raw and in need of sleep after the recent low followed by a night of mopping up seawater, so I left two reefs in the working jib and started sleeping at 9pm. Wind veered into the SW overnight and put N in our course–we don’t need more north!–but I let it stand until morning, and that was the only change to the wind all night. I rose at 6am feeling more myself.

With the day, wind came on a steady 30 – 35 knots and the already lumpy sea grew with it. I carried this on the beam for a course due E until we fell off a couple stallions. Then I decided to run N with the herd for a few hours instead of across their bows. Now winds are back down to mid, high 20s, seas are moderating, and our course is back to the E.

Noticeably warmer up here. I’ve divested of a layer of fleece.

My goal after rounding Cape Horn was to head for 47S and have that as my target latitude for the trip around, but I’ve decided to stay the week at 44/45S. Mid to long range forecasts show a developing high right below us, and then a week on another Rio Low*, similar to the one we just weathered, will sweep through this area. If I’m too far south, it will give me a few days of strong easterlies (ug!); if I stay up here, the wind will be strong but favorable…so says the forecast.

Why 47S as a target latitude?

Tony Gooch (previous owner of this boat) has spent significant time in the south, and when he circumnavigated in 2002, his target latitude was 47S and with good results.

Our spin around the south last year was also largely at 47S and also with good results, save a specific low near the Crozet Islands.

What figures into a latitude choice?

-Distance. The distance around grows shorter the further south you are. For example, I believe the Golden Globe Racers have a southern limit of around 42S. The circumference of the globe at that latitude is 16,051 miles. Compare that to 47S, whose distance around is 14,731 miles, shorter by 1,320 miles or 10 days at 140 miles a day. (This is idealized and doesn’t take into account the changes in latitude due to weather or the dip for Cape Horn and New Zealand.)

-Weather. Summertime lows tend (emphasis, tend) to have their centers below 50S. In a region dominated by east-trending lows followed by calms, the further into a low you can be the stronger your wind and the longer you’ll carry it. You’ll be fast. That’s the upside. The downside is rather obvious. Stay too far south and you can get the stuffing beat out of you.

Clearly one can have different strategies for different sectors. In the Indian Ocean, for example, I’m considering a latitude well above the Crozet’s. Call me shy; that’s ok.

So, we’ll stay up here for the time being and then trend down as winds allow.

*Rio Low. The lows that march across the south often develop further north and then swing down as they intensify. The one that knocked us down last year in the Indian Ocean began its ugly career just off the coast of Rio de Janiero. So did the low we just weathered. And the one upcoming.

This article was syndicated from The Figure 8 Voyage


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