Friday, November 21, 2008

Chris Bedford, Ericsson meteorologist: Finally...progress!!

[Source: Chris Bedford, Ericsson meteorologist:] This morning, the two Ericsson Racing Team boats will start to appreciate the fact that they are well and truly making progress north toward the finish in Cochin. After a minor slow down today and early tomorrow, Ericsson 3 and Ericsson 4 will accelerate north in the SE trade winds of the southern Indian Ocean beginning tomorrow afternoon/evening.

Today, a NW wind ahead of a strong Southern Ocean cold front is pushing the boats on a course toward the north – northeast and they have made excellent progress to outrun a high pressure area which had been chasing them down from the west. They should continue north with the front which is expected to run over them somewhere around 30S this evening and about the time they cross into the sub-tropical high pressure ridge and eventually into the SE trades tomorrow. This crossing could get a little awkward with some wind holes and isolated showers popping up, but they should be in the SE trades sometime later tomorrow morning.

Crazy conditions aboard Ericsson 3. Southern Indian Ocean, 20 November 2008. Video copyright Ericsson Racing Team

At present, the trade winds look relatively strong and consistent. I am expecting themto hold 20 knots of reaching SE’ly breeze in the trades all the way to the southern boundary of doldrums which is now at about 9S. There may even be an area of 25+ knot SE’ly around 15S just before the early easing begins at 12-13S. At present, the doldrums crossing looks a little easier east of Diego Garcia rather than west.

It is not easy to discern advantages/disadvantages in the positioning of Ericsson 4 in the east vs Ericsson 3 in the northwest at the moment. Certainly, Ericsson 3 is in a more commanding position which might allow covering. This will become less possible once the boats are locked into the trade winds.

At the moment, the computer routing has a slight edge in the routing calculation going to Ericsson 4… but only in the long term. In the short-term, Ericsson 3 has the best advantage and should start closing miles on the finish more quickly. Given the way the doldrums are presently shaping up, there is now a very good chance that the fleet will shift further east and may actually get east of the longitude of Cochin as they search for a quick passage of the Indian Ocean doldrums. We saw such a solution in our historical record about 40% of the time, so there is precedence for the expected long term routing. Unfortunately, these doldrums can be pretty difficult to forecast much more than 3 days out, so any routing solution using forecasts today has at best a 60/40 probability.

Ryan Godfrey and Phil Jameson, Ericsson 4 bowmen. Southern Indian Ocean, 20 November 2008. Video copyright Ericsson Racing Team

Ericsson 3 does not have their radar working after an incident shortly after the start. In addition to tracking competitors and possible obstructions, the radar can be an important piece of equipment for monitoring the position and movement of rain squalls in the upcoming trade winds and doldrums. I spent a bit of time reviewing squall/wind management and radar tracking with skipper Anders Lewander and navigator Aksel Magdahl before the start of Leg 2. I hope a lack of the radar will not hamper them significantly in squally trade winds ahead.

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