Wecoma daily report, 24 August 2001

We deployed the SeaSoar, HTI bioacoustics instrument and the iron sampler at the east end of line 8 off the Umpqua River at midnite on Thursday 8/23. At 1630 on Friday 8/24, we are halfway complete with line 6, towing north on Bigbox 5. For this Bigbox, we have swapped out the ac-9 (nine wavelength light absorption and attenuation meter) on top of SeaSoar in favor of a new optical instrument which measures nitrate. ISUS (In Situ Ultraviolet Spectrometer) is Ken Johnson's (MBARI) optical nitrate sensor and its adaptation for use on SeaSoar was carried out by Luke Coletti (MBARI), Zanna Chase (MBARI), Jack Barth and the OSU MarTechs. We plan to conduct some comparison profiles next to the Thompson late tonight in the vicinity of Stonewall Bank. We can then compare ISUS nitrate estimates with those from Burke Hales' pumped profiling system.

The two southern lines from Bigbox 5, lines 7 and 8, show that the equatorward upwelling jet is still present on the offshore side of the Bank, but it is almost completely empty of chlorophyll. Both the warm surface layer and the previous high surface chlorophyll have been pushed back to the coast by the onshore Ekman transport in response to the strong southerly winds. We see clear evidence for downwelling near the coast.

On line 7 over Heceta Bank, roughly 25 km from shore off Florence, we observed a pod of 6-10 whales feeding and spouting in a region that had strong zooplankton returns from the HTI bioacoustics instrument. See a nice figure by Toby Martin at http://pigeon.shipops.orst.edu/coast/pod24aug2001.gif

Around 1330 on Friday, John Bane flew over while we were near shore between lines 6 and 7 off the Heceta Head lighthouse. He flew several low-level passes to obtain data to compare with our "sea truth." We obtained some nice pictures of him streaking by at 120 knots with the coast in the background.

We plan to complete Bigbox 5 late on Saturday afternoon and to dock in Newport at 8pm on Saturday night. We'll join the Thompson gang who will arrive there earlier around 6pm. Unloading will be in full swing Sunday and Murray Levine's mooring recovery cruise will depart promptly on Monday morning.

It's been a highly successful second COAST cruise and we're looking forward to working on the great data sets we've obtained.

Submitted at 1700 on 24 August 2001 by Jack Barth, Chief Scientist,

R/V Wecoma