Thursday, February 28, 2013

Almost Halfway There –– Past Halfway There

It depends on how you want to count it.

Latest JRH position is

 04:00 Mar 01 UTC is  18.3419 N, 41.246 W 

2h SMG=1.0kts, CMG=302,   24h SMG=1.3kts, CMG=286 

2204.59 nmi to Miami  (about half that to nearest land in the Caribbean)

They started at Dakar, Lon 17º 31’W, with a Destination of Miami,  Lon 80º 08’W, so the halfway mark is at Lon 48º  49.5’W.

It is perfectly fair to say whenever they cross that line they are halfway to Miami, regardless of latitude.

On the other hand... the Lon of the Windward Islands of the Caribbean is about 61W, which would have put the halfway point to “crossing the Atlantic” in general quite a ways behind them now, back at 39.5W

It has been tough slow going, but they are making steady progress and are in this sense on the downhill side of a long trip.  Good work guys!

By the way, their GC course is going to start *very* slowly coming down as they  proceed, and now it is just crossing on to 288T from the previous 290.  They have been doing excellent job on average course made good in unseasonally unfavorable seas.

Tuesday, February 19, 2013

Big eddy on the horizon... Maybe!

You may well have detected that we are struggling to try to understand and be able to predict on some level the ocean currents the boat must navigate.  We have mixed success. We did see a big eddy some days ago and there was definite evidence they felt some of it, but details of the prediction did not seem to pan out.

Now we approach another monster eddy at about 18N, 40W and will have another chance.  To see this one, first go to their latest position plot, that shows where they are relative to a zoomed in view, then go to 6-day forecasts and scroll the pics.

This eddy has been there for many weeks now according to RTOFS.  We have yet to get confirmation of it from other ocean models.

Note that at the time of writing here (19z on Feb 19) the boat is moving at 4.3 kts to the west.  If this is real data then they must be in a strong (>2 kts) current now. They cannot row that fast.

You can check latest position and progress at JHR position update.

We shall see...

Sunday, February 17, 2013

Progress Reports Automated

If you would like to get progress reports of the boat that look like this:

You can use any browser on computer or phone and go to this page:

and then set a book mark. This updates every 2 hours, at 5 minutes past the hour. It shows the present Lat and Lon as well as the course and speed made good over the past 2 hr and over the past 24 hr.

On iPhones, you can press the bookmark button and create a shortcut on your screen, and then just tap that screen icon to see how things are going.

Friday, February 8, 2013

Riding along on the Big Red Bus

The team has been making excellent progress, over 3 kts right on the great circle route, but now they are taking a break on sea anchor till daylight.  The winds are picking up and they have no moon at all till about Feb 15 (then 30% illumination). It is difficult to steer a good course in the waves when you cannot see them coming.

Even on sea anchor last check showed then drifting W-NW even with strong wind pushing them SW!

In short, they are ideally positioned in the large current eddy at the moment, shown below. They should get help from this for another couple days.

Looking ahead, there is even a much larger eddy down the line (picture below), which we can hope will still be there when the boat gets there. These mesoscale eddies can last a month or more in about the same place. They are rotating clockwise, with current speed in the eddy varying as patches of faster water rotate around the circle.

Note the picture above is a zoomed in corner of the smaller one in the bottom pic, SE corner, just west of Cape Verde. At the moment, 22z on Feb 8, the boat is in the yellow water just entering the red patch.

Tuesday, February 5, 2013

Curent action on the horizon

Check the daily current updates to see that there is a large eddy ahead of the boat, and you can scroll down the images to see that if all stays the same, the boat will enter this current on feb 7 at 00z, which is thursday, feb 6 at roughly 4pm seattle time.

 This is worth noting for a couple reasons.

First it might be our first real check of these current predictions, and second, it could be a very nice ride for the rowers. The red parts in the GE picture are 4 to 5 kts, so keep tuned in. Thursday is the big day.

The pictures below are the RTOFS predictions initialized 00z on Feb 5, valid for 00z on Feb 7 .

Note that the rowers have to hold the excellent  course they have been making.  If they fall off to 275 T they will miss the big red bus.

If they do hit the current it looks to be SW, but if they keep rowing 2+ kt to 300 T or so, they will make great progress to the west, and maybe even get to ride it up the other side.

The big picture