Return-Path: robin@icess.ucsb.edu Delivery-Date: Tue Feb 1 08:48 PST 200 Received: from [128.111.102.198] (QR3.msi.ucsb.edu [128.111.102.198]) by guardian.icess.ucsb.edu (8.9.3/8.9.3) with ESMTP id IAA28285; Tue, 1 Feb 2000 08:47:59 -0800 (PST) X-Sender: robin@mail.icess.ucsb.edu Message-Id: Mime-Version: 1.0 Date: Tue, 1 Feb 2000 08:50:30 -0800 To: lterpalpi, quetinla@nbp.polar.org, fraserbi@palmer.usap.nsf.gov From: Maria Vernet (by way of Robin Ross) Subject: LMG WEEKLEY SCIENCE REPORT 9-16 Jan Content-Type: text/plain; charset="us-ascii" Content-Length: 5196 ARSV Laurence M. Gould REPORT 9-16 JANUARY 2000 Long Term Ecological Research (LTER) Cruise We left Palmer Station on Sunday 9 January after a day of loading instruments and personnel. The first morning we sampled 2 shallow stations in Arthur Harbor to continue the seasonal sampling in the area and we sailed immediately after towards the continental shelf where we carry out the annual January cruise. This year, due to ship scheduling constraints, we will have a reduced sampling scheme from 9 to 25 January. Details of sampling stations and methods can be found in http://www.icess.ucsb.edu/lter/field. The northern part of the sampling grid (600 line, west of Anvers Island) showed daily primary production rates lower than the average of the last 5 years. Nutrients (silicic acid, phosphate) concentrations were higher than average while ammonium concentrations were somewhat lower. We saw krill at most stations but in very small numbers. Among the krill we caught female krill ready to spawn. The acoustics transects showed only low-density returns and a typical pattern of a solid line of signal between about 20-50 meters depth rather than the discrete, higher-density patches typical of krill schools. Salps in large numbers were found in deep water (>2000 m) outside stations on the 600, 500 and 400 lines. We've also had heavy phytoplankton in the 1-meter net at these stations (335-micrometer mesh). Our observations the seabirds and marine mammals from the bridge showed higher numbers of pelagic seabirds off shore in the higher latitudes. Large feeding groups of southern fulmars (Fulmarus glacialoides), gray-headed albatross (Diomedea chrysostoma), and black-browned albatross (Diomedea melanophris) were seen in the off shore portion of the LTER grid. Also large aggregations of Wilson's storm petrels (Oceanites oceanicus), and giant petrels (Macronectes giganteus) were feeding together. Our diet sampling and foraging grid work observations, which make up the greater part of our work is scheduled for later in the cruise. No foraging groups of pygoscelid penguins were observed during bridge observations. The Profiling Reflectance Radiometer (PRR) worked well and was successfully deployed at each of the 24 stations at an average depth of 66m, and provided light levels for determining depths at which the following CTD/rosette cast bottles would be closed. Chlorophyll samples from an average of 8 depths from the CTD/rosette cast (total 198) were filtered through 0.45um filters (surface and chlorophyll max depths were first filtered through 20 micrometers). All filters were placed into scintillation vials and are being kept at -80C. Acetone was not added to the vials to prevent extraction until final fluorometer calibration could be assured. Ice observations have so far been minimal since very little sea ice has been encountered. Full depth profiles were been collected from all stations for dissolved oxygen (DO). The top 100 m of the water column was sampled for dissolved organic carbon (DOC), lipopolysaccharides (LPS), microbial numbers and community structure by flow cytometry, ectoenzyme activity (L-aminopeptidase) and microbial growth rates by leucine and thymidine incorporation. Dissolved inorganic carbon (DIC) samples were collected as full profiles from the 600-line and 3-4 samples per depth profile for the other stations. We have also been trying to target sampling of DO's and DIC's in regions of the water column exhibiting characteristics of circumpolar deep water (CDW), i.e. high temperatures and high salinities. The DO's have been analyzed and the data made available on the Public directory in the LMG001 folder under "Oxygen". The ecto-enzyme activities will be posted also. Analyses of the other samples will be completed at the home institution at University of Hawaii. This far into the cruise everything is running smoothly. We have had a week of sampling uninterrupted by bad weather or instrument malfunction. All research groups have had a successful first week of sampling. The equipment has been working well. Our volunteers learned the sampling routine quickly and are all doing a great job. During the first two stations near Palmer Station we had guests from Palmer Station on board, Mary (Mimi) Wallace, a high school teacher from El Paso, Texas, on the TEA program, reporters from US World and News (Charles Petit and Jim LoScalzo) and Gary Braasch, a photographer. We will welcome them back on board the last day of the cruise on 26 January. Mimi Wallace journal can be found at the 00jan cruise page http://www.icess.ucsb.edu/lter/field/00jan. During the next week we will finish the sampling on the shelf of the Western Antartica Peninsula from Anvers Island to Marguerite Bay. We will also visit Rothera in Marguerite Bay and carry out sampling on birds, krill and physical oceanography with personnel from the British Antarctic Survey. We thank ASA personnel (Randy Sliester, MPC) and the ECO crew (Robert Verret, Master) and personnel in Palmer Station (Robert Ferrel, Station Manager) for their support on carrying out a successful sampling program. (Maria Vernet, Chief Scientist)