Saturday, February 21, 2009

Ericsson Meteorologist: The Race Enters a New Phase

[Source: Chris Bedford, Ericsson Team Meteorologist] Greetings everyone, I’m back. As you may know, I’ve been submitting a video weather blog entry for the web site over the last week. This change has been in response to the limited video and images available off the boat while they are in a broadband blackout caused by some satellite repositioning by INMARSAT. No video updates over the weekend, so here I am back with my more typical written update.

Today, we have big changes literally on the horizon. The incredibly fast progress of the last week has put the fleet ahead of schedule on their trip toward Rio, but the coming days will offer some serious challenges as the wind will shift dramatically from reaching to upwind angles and decrease considerably in speed. I fully expect them to be put back on schedule by lighter, more variable winds over the next week to 10 days.

Plotting the fleet position on the weather satellite image today shows Ericsson 4, Puma, and Ericsson 3 sailing in underneath considerable cloud cover which marks the Intertropical Convergence Zone. These clouds are filled with showers and thundersqualls resulting from the massive convergence between the northeasterly trade winds blowing around the north Pacific high pressure and the southeast trade winds blowing out of the Southern Hemisphere. The 20+ knot reaching conditions are about to end – first for Ericisson 4, then progressively for Puma and Ericsson 3. Telefonica Blue and Green Dragon are likely to hold onto the northeast trade winds for nearly one more day and perhaps even longer for Green Dragon since they are well to the east and likely to hold onto the favorable pressure for much longer.

Tactically, you may have seen the boys on Ericsson 4 suddenly jump ahead in the last 12-18 hours from around 5 miles ahead of Puma to about 50 miles. Its pretty clear that they understood the coming light spot would tighten up the race and felt it was time to cash in on the easterly leverage they had worked hard to keep since leaving the Japanese Current earlier in the week. Now, as soon as the wind dies at the head of the fleet, the trailing boats will have a chance to regain some of the miles lost in the last 24 hours. In fact, on the 1600 GMT position report, Ericsson 4 appears to be just a few miles from running into the lighter winds. They are still showing 20 knots, but I expect them to be in much different conditions on the 1900 GMT position report.

Ericsson 4 is passing just to the northeast of a small island called Kosrae and the last weather report there was showing winds at 5 knots from the northeast – a far cry from the fresh trades they have been experiencing and foreshadowing much of the light airs which lie ahead. The clouds, showers, and squalls are going to randomize things for the next 12-24 hours and until the fleet moves out of the ITCZ and into a region of light, east-southeast winds from about 4N. South of the 4N, this zone of very light winds extends nearly 1500nm to the southeast and right along the course the boats need to sail toward the scoring gate at 36S latitude. 36S is still over 3000 miles away. It could take the fleet the better part of 10 days to get there! Time to be patient as the days and miles will pass much more slowly.



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