Friday, December 18, 2009

Day 10: 09.35.065'N 046.27.017'W, 131nm (24h)

December 17, 1200 UTC
Distance to go: 563nm
Wind and waves: NE 11-17kn, 3m
Sails: Main, genoa and cutter, wing and wing

'The Washing Machine', 'Hotse Klots', 'The Klotsbak', 'Neptune's Sneeze' are some of the names coined by various boats to describe a very strange phenomenon that generally catches us about twice per day. You can be sailing along on a sunny day on a relatively calm sea when suddenly the boat starts to be thrown around on short choppy waves coming from all directions, crazy currents, white caps on the waves accompanied by loud whooshing noises. All this with no change to the wind or sky. Not scary as the waves are small but very distinct, uncomfortable and surprising. The most strongly supported theory is that these are eddies caused by interactions between warm and cold water rivers running through the ocean and reacting with one another. These rivers move not only along the surface but also move up and down in various depths. The water temperature can vary between 27 degrees on the surface to 4 degrees in the depths and the volume of water varies as a result, reducing with the increased pressure in the depths. The largest temperature difference is found between 50-100m deep (no more sunlight). This temperature difference causes various vertical currents of expanding and contracting water movements which manifest themselves in the crazy eddies we experience on the surface. Ancient mariners used to think that this effect was caused by sea monsters fighting just under the surface. Thanks to Jimmy Lengkeek for the scientific explanation. We do still glance apprehensively over the side of the boat from time to time in the hopes of catching a glimpse of the mighty deep sea dragon.

Other than the sea dragons we are sailing in relative comfort. The waves are large but incredibly long and rolling so the movement is rhythmic and comforting, rather like sailing on a dynamic English countryside. Much more comfortable than the short choppy waves that we experienced in some of our coastal sailing. We expected to have 0,5-1,5 knots of current with us for much of the journey from the equatorial current running east to west, but alas, we seem to have only current against us to date. Perhaps in the coming days.

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