UCI at sea: A scientist's diary

A seven person UC Irvine-Chapman University research team is traveling across the Pacific Ocean, taking water and air samples that will better clarify the effect that certain chemicals, such as methyl bromide, have on the ozone layer. The team is being led by UCI researcher Eric Saltzman, who is sending periodic reports to the Orange County Register from the research vessel Wecoma.

Latest dispatch: June 15, 2004

Here we're at 11N, steaming pretty much right towards Hawaii. I was hoping we would leave the clouds and rain of the tropics behind as we head north. Eventually we'll reach air moving downward, subsiding, rather than uplifting. That should give us sunny, blue skies. It certainly hasn't happened yet. As we get away from the Intertropical Convergence Zone, instead of getting calmer and clearer (like it is supposed to), it's gotten darker and stormier. We had some weather last night and this morning and things started to get a bit lively. First of all, the clock fell off the wall - which aparently has never happened on this ship before (according to the crew). There's a lot of seawater flowing across the fantail (or rearmost deck) because of waves breaking over the deck. This was a problem because it damaged some of the rigging holding our outdoor equipment in place.

We had to temporarily bring in one water bath (a large plastic tub for irradiating water samples in sunlight). The plywood base for our air/water equilibrator also cracked apart from being underwater too much, and the crew added a metal brace to keep it in place. The equilibrator is like a 2 foot tall plexiglas shower that mixes air and water, so we can measure the composition of gases dissolved in seawater. We also have air intakes and wind sensors mounted on a large pole, or jackstaff, mounted on the bow. During the late morning, I had the great idea of turning a bit into the wind to make the ship roll less. So, instead, we plowed into the seas, sending some great sprays of seawater over the jackstaff. This was not a happy sight for me, since there is about $35,000 worth of borrowed equipment up there that I'm responsible for. Also, if it gets wrecked one of our experiments is over. Sure enough, about an hour later, all our wind sensors (a sonic anemometer) quit working. We had to turn the ship about (to stop the constant spray) and investigate. To make a long story short, one wind sensor bit the dust (or the spray, as it were). Happily, we got the other sensor working again, and we were back in business. Fortunately, we had two sensors measuring the same thing, so we could afford to lose one and still complete our experiment.

I know I've already said plenty about the pump for the ship's water system, but I couldn't resist one last note. This is the pump that broke, got repaired, broke again, then the replacement that was shipped to Christmas Island, Australia instead of Kiribati. As a result, we've been on water restrictions for more or less the whole cruise. Well, the pump did actually make it to Kiribati just as we got to within a day of Christmas Island. Unfortunately, it went to the island of Tarawa, which is hundreds of miles west of us, and there were apparently no direct flights to bring it anywhere close. I was actually rather pleased about this, because I had bet with the Captain that the pump would not reach our ship before Hononlulu. Amazingly, the ship engineers have kept the evaporator running long enough to fill the tanks, and with only a few days left until Hawaii we can take regular showers and wash our clothes.

Dispatch: June 11, 2004:

We're steaming south to Christmas Island to fetch our water pump. The seas have kicked up and there's a decent size swell which is causing this small ship to roll quite a bit. Suddenly simple things get quite challenging, since you have to work hard to keep your balance. All the nice weather had made us lax about tying down equipment too, and a couple of big rolls caused a flurry of lab cleanup and equipment tie down.

As Chief scientist, my job is to try to integrate everyone's measurements, and to give everyone a broad view of what we're learning as we go. This is tough, because what I get are fragments of preliminary information from each of the researchers. Sometimes their data make a clear statement and sometimes they don't. For example, we've steamed across water masses with very different biological productivities, and we can see marked changes in the trace gas contents of different waters. But until we can get all the data plotted on a map showing what we found where and when, it's hard to fit the chemistry together with the oceanography. The question of which hemisphere we're in remains a mystery. The meteorology looks like we're in Southern hemisphere air, but the air chemistry says we're not.

One very nice scientific result came yesterday from UCI graduate student Elizabeth Dahl. She took some seawater from about 50m depth, filtered it and irradiated it with sunlight on deck, and measured the growth of some trace gases called alkyl nitrates. The waters produced alkyl nitrates, in good agreement with Shari Yvon-Lewis' measurements showing that these waters are supersaturated with these gases relative to the overlying atmosphere. Alkyl nitrates are common pollutants in smog, but they're also found over clean ocean areas. Elizabeth's thesis work is testing the hypothesis that these gases are produced photochemically in seawater. She's done a lot of laboratory work, but there's nothing like proving your theory on real waters.

As we've moved eastward, the waters have become more productive. We see more flying fish, and today one jumped on board. We also saw porpoises for the first time on this trip - always a great sight.

Dispatch: June 9, 2004

We've started our last zig-zag across the Intertropical Convergence Zone(0-6N), before we head north to Hawaii. Nighttime activity is increasing on the ship, as we start to get more ambitious with our sampling plans. Last night we took depth profile water samples at 2am to try to sample during the near surface fluorescence maximum - this signals the vertical migration of microorganisms and we want to see how they influence trace gas levels.

Of course, working at night means more equipment crises at odd hours. Last night at around midnight one of our air pumps began to fail. It took us about two hours to understand the problem, and to come up with a solution. We discovered that our steel-toed rubber boots are made of exactly the same stuff as the pump diaphragms - great luck, and we were just about to cut up a pair, when we discovered that the ship's engineers have a huge stock of proper gasket material. So, we settled all that around 1AM, took water samples at 2AM, and by 3AM a gas chromatographic oven had quit working due to an electronics failure. Our fixit expert, Cyril, was roused again and had that one working by 4AM. By then it's time to watch the sunrise.

Today was quite clear (unusual in the ITCZ where it's normally cloudy) and starwatching was excellent. The sky here is wonderful - not only is the sky nice and dark, and the milky way is uminous. You can also see constellations in both hemispheres at the same time - the big dipper one side and the Southern Cross on the other.

Today we got and email with a synopsis of the BBC news. We haven't had much news on the ship. I normally read the newspapers every day, and it felt odd for the first few days at sea not to know what's going on in the world. After a week or two, though, politics and world affairs seems rather remote and I figure that the world will somehow muddle through without my knowing everything that's happening.