PLEASE NOTE: This post belongs after “Westward to Distant Marquesas” and before “Broken Shroud.”
This passage isn’t going the way I pictured it. No surprise, right? None of the places we’ve visited have matched my preconceived notions of what they’d be like. But I’ve crossed oceans before, so I thought I knew what to expect at sea. After a few hundred miles sailing or motoring SW from the Galapagos, we should hit constant trade winds of about 15 knots, and be zipping along on a broad reach under spinnaker for the last two-thirds of the trip. We’re going into our sixth day, and we’re still looking for that constant trade wind, and we have yet to set a spinnaker. Right now we have about 10 knots, from the expected SE. But for much of the day we had 7 or 8 knots — very light. Plus patches where it changes 45 degrees and/or nearly stops blowing. What’s happened to the trade winds!?
And what should our strategy be to make the most of the situation? The wind is generally stronger further south. And when the wind is light, we sail fastest on a close reach — going across the wind rather than with it. So we’ve been continuing to sail SW, beyond what we had planned. Getting more South, and keeping our boat speed up. We are now south of the two boats ahead of us. Soon we will have to turn west for the Marquesas. Will our additional “southing” give us a payoff, or are we simply sailing unnecessary added distance?
We make our guesses about the trade-offs based on “grib files” — wind predictions that we receive via the SSB radio, in a .GRB file format. I don’t remember what GRB stands for, if anything. A file is very slowly coming in over the radio now, as I write, but the software estimates it will take another 35 minutes to completely receive it. It will show wind predictions every six hours for the next two days. Based on what, I honestly don’t know! How much data is available, and how much is interpolation? [We have a drifter buoy aboard, that we will be deploying when we get to 108 degrees west longitude. That will add one more data point. Other BPO boats are deploying buoys at various longitudes, but still there can’t be all that many buoys transmitting weather data…]
Based on the previous grib files from the previous two mornings, we expect to see a trough of confused and light winds to our north, and gradually stronger winds as one moves further south and west from there. Two days ago it looked like we were far enough south to avoid the messy area. Yesterday it appeared that we would have to get further south. Today…we’ll know soon.
Jimmy Cornell likes to say that GRB stands for “garbage,” and we should ignore these predictions. Or at least not “outsmart” ourselves by taking the predictions too seriously, and making course changes on account of them. Yet that is what we’re doing, and so far the gribs have been helpful. We’ll see over the next few days if our southing has a payoff…
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GRIB: GRIdded Binary files