Saturday, March 29, 2008

A Foggy Day, with Big Things Coming up Tomorrow

What a surprise when I woke up this morning! The water was just about like glass (the antique ripply kind), and we were socked in with fog, so visibility was less than a mile. So on the one hand, it was ideal viewing weather, with no whitecaps to confuse the eye. On the other hand, with such low visibility, there was no question of using the Big Eyes – the naked eye could distinguish pretty much to the fog line, and even if we could see a little farther with the Big Eyes, there was no horizon against which to measure distance.

So, what makes fog? Cold water! It was sweatshirts and jeans weather today. You can see Robyn and Allan demonstrating the chilly weather.

We are at about 32 degrees north latitude (compared to about 21 or 22 degrees for Oahu). It turns out we drove through a tiny neck of the transition zone chlorophyll front during the night and are well and truly in the transition zone toward subarctic waters now, where the water is colder, more nutrient-rich, and more productive. We surmised this by looking at where our track fell on a Debris Estimated Likelihood Index (DELI) map that NOAA CoastWatch put together for us. The area of greatest convergence appears to be right along the chlorophyll front, so tonight we’ll go east to try to find a deep blue area on the DELI map, where the convergence zone is thicker.The plan for tomorrow is to start with the unmanned aerial system (UAS) work. Here are the ATI guys--Chuck, Tim, and Mike--giving the Malolo I some fresh air on the bow this morning.

If we can get out of the fog and into an area with some debris, the Malolo I (the UAS) and the small boats will be launched. Tonight we’re on what may be our last CTD station. The dedicated folks who’ve been working the 7:30pm to 7:30am shift can become daytime dwellers again. And many of the CTD crewmembers are ready to switch over to small boat operations. One boat will be following the Malolo to keep it in line of sight, per Federal Aviation Administration regulations. The other will be approaching debris that’s spotted by the Malolo or the Big Eyes.

The idea is something like this: the DELI maps will indicate where we should aim, the ship’s fluorometer counts will indicate when we hit the high-chlorophyll areas identified on the DELI maps, the Big Eyes will signal when we’re actually seeing a lot of debris, and the Malolo I will fly over areas that seem to have high debris density to compare what can be seen from the air with what can be seen from the flying bridge of the ship. When one of these platforms (the Malolo or the Big Eyes crew) spots a good-sized bundle of fishing gear, one of the small boats will approach it and truly ground-truth (ocean-truth?) the observations. At that point, there are a couple options, depending on the size of the debris bundle. If the bundle is too large to bring on board, the small-boat crew can attach a satellite drifter buoy and continue to track the movement of the bundle over the next year or so. If the debris is small enough that it can be dragged into the small boat or towed over to the ship, it may be possible to use the ship’s crane to lift it on board and into the Pepto Dumpster, a shocking pink container that was brought aboard in hopes that we can fill it with derelict fishing nets.

The key for tomorrow is be prepare and be flexible. Much is up to the weather and the technology. Our Big Eyes crew has been training hard for five days, and we’re ready to do our part. Wish us luck!

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