VOR Model Behavior We've
not given Brunel much love during the VOR.
Here is an onboard report from them on Leg 8. After a previous good night and day we have struggled a bit in the slightly fresher conditions (13-17 knots). We are missing just a little bit of pace that, slowly but surely, drops us off the back. So we look to the lighter conditions ahead overnight to try to get back into the game. We get two major met models onto the boats; the UKMET every 12 hours and the US GFS model every 6 hours. The GFS is received in good order (6 hours after initialization time) whereas the UK met comes 12 hrs after initialization time and only twice a day. We also get the ww3 model which is a variant on the GFS. It is great when they all agree as we then have high confidence in using them. The problem comes when they have a different view on a situation. Which do we follow? We are in the UK so the UK met office should be able to forecast correctly for their neck o f the woods. But in a situation where the forecast conditions are unstable and not consistent from model to model what then should we use. The good old GFS comes every six hours and so we can be in a situation where the UK data we are relying on is 23 hours old while the gfs at the equivalent time is only 11 hours old! We also get UKMET charts every six hours so we can at least compare them to the UK grib for consistency but there is still a reasonably high level of uncertainty. I should also add that none of the models have dealt especially well with the sea breeze situation in recent days. The reality has been that the wind is more right and stronger inshore during the day as a result of the sea breeze. Luckily this is able to be predicted from experience (and then tested out). Those going in won out all day yesterday. Today though the rhumb line is much further off the coast, and while there is plenty of heating (land temps 20-25) there also is more cloud cover today. Back to the discrepancy in the models: to cut a long story short, a weak trough is approaching us from the west followed by high pressure (ALL LIGHT WIND AND SLOW PERIOD), then another low brings decent SW winds. This all happens over the next 24 hours. The US grib is upbeat and suggests chasing north hard to get the new SW winds while the UK grib suggests just plodding and going slow in the light (accepting your fate)and waiting for the wind to come to you. (I often reflect with a wry grin how often the models reflect their heritage.) So we are somewhere in the middle chasing a bit to the north. Consequently the fleet are all inshore of us. I guess time will tell who wins out! Well the 12z weather is now available. I'd better grab it and see how the story is unfolding. Cheers, 06/07/06
Brunel's Hell So here they were having a decent leg, with a for them good fifth place finish on Leg 8...but no. That result has been scratched due to a navigational error on the final approach to the finish. 30 miles from the Rotterdam finish, Brunel missed the MSP special purpose buoy, which was put in as a mark of the course to direct the fleet down the Dutch coast, rather than have them approaching directly through the busiest shipping lanes. The Brunel crew only learned of their error when it was revealed to them by race officials who had followed the satellite tracking and watched them sail directly to the finish from the turn off the north east corner of Scotland. Faced with the prospect of being protested by the race committee, Brunel retired from Leg 8. Can it get any worse for them. Wait, don't ask... 06/12/06 |