PALMER STATION SCIENCE SITREP DECEMBER 1997 NEWS FROM THE LAB. Rob Edwards, Senior Assistant Supervisor, Laboratory Operations The month of December brought unusually good weather to Palmer Station this year. Ten days were clear or partly cloudy, and average air temperature was 1.5 C. As the summer solstice came and went, surface ocean temperatures rose above 1.5 C. Portions of the Marr Glacier in Arthur Harbor are regularly calving throughout the day. In general, light winds and open water with only local brash ice meant that boating activities were continuous throughout the month. Research field activities proceeded at a rapid pace, as researchers took advantage of the good conditions. Laboratory space was still rather crowded, with the laboratories supporting up to 19 researchers from eight science projects during the month. We are now able to download Sea-viewing Wide Field-of-view Sensor (SeaWiFS) imagery on the Palmer Station Terascan computer system, in addition to the DMSP and NOAA satellite data previously available. SeaWiFs data are collected from the commercial SeaStar satellite, providing ocean color images covering the visible spectrum over cloud-free areas. Palmer Station continues to collect meterorological data, and we are comparing these with data from our new automatic environmental parameter sensors. We also log tide gage data, including tidal height, water temperature, and conductivity. Facilities improvements continue when possible. Two of the seawater supply pumps were rebuilt, increasing the pressure available to the aquarium. The seawater intakes were inspected by research divers from S-007 and S-028. The intake screens were in good shape, though a number of the zinc anodes on the pipes were highly corroded or completely missing. The tourist season is full upon us, with three visits by cruise ships to station. Laboratory staff participate as guides during the planned visits, ensuring minimal disruption to research activities. The tourist display aquarium is maintained by station staff, and continues to be a highlight for many of the tourists, giving them an appreciation of subtidal marine organisms otherwise not available to them. S-003 OZONE DEPLETION, UV-B RADIATION AND VASCULAR PLANT PERFORMANCE IN ANTARCTICA. Thomas A. Day, Department of Plant Biology and The Center for the Study of Early Events in Photosynthesis, Arizona State University, Tempe, AZ 85287-1601. PERSONNEL ON STATION: Christopher T. Ruhland, Fusheng Xiong and Erin C. Vining. Studies continued on the influence of UV radiation and warming on the two antarctic vascular plants Deschampsia antarctica (hairgrass) and Colobanthus quitensis (pearlwort) on Stepping Stones Island. Examination of possible re-greening of Colobanthus shoots from plants emerging from under snow revealed high initial growth rates early in the season. Tagging of individual shoots of both Deschampsia and Colobanthus for Demographic Growth Analysis was completed in early December from treatment cages that modify UV radiation and temperature in the main plots of our experiment. Photographs of individual cages for estimation of species cover are being performed every 14 days. Addition of fertilizer or water to examine possible nutrient limitations to plant performance has been added to twenty additional cages in the main plots. Seven rain gauges have been added under representative treatments to examine possible differences in amounts of precipitation received under each of the treatments. Three Campbell microloggers have been added to our main plots that monitor ambient levels of UV-A, UV-B, visible light, air and soil temperature and relative humidity over the course of the growing season. An additional 25 treatment cages have been added to the northeast side of Stepping Stones Island to examine treatment effects on measurements that require destructive harvesting of plants. For each species, 175 shoots have been tagged under these cages to examine potential UV-induced constraints on leaf elongation. Initial measurements of epidermal cell size and number have been examined with a fluorescent microscope on both species. Shoots have also been marked for biomass analysis at the end of the season that will allow measurements in our non-destructive main plots to be expressed on a dry-mass basis. In addition, samples of both species were collected in liquid nitrogen for transport back to Arizona State University. These samples will be analyzed at the United States Department of Agriculture Cotton Research Lab for Rubisco Activase activity. Samples will help elucidate molecular mechanisms responsible for temperature limitations to photosynthesis. We thank ASA support for helping to make this a productive month at our field site. S-007 UV-PHOTOBIOLOGY OF PLANKTONIC DEVELOPMENTAL STAGES OF ANTARCTIC BENTHIC INVERTEBRATES. Deneb Karentz, University of San Francisco and Isidro Bosch, State University of New York at Geneseo. PERSONNEL ON STATION: Deneb Karentz, Mario Pineda and William Jaeckle On December 12 Sid Bosch and David Krakowski departed station and Will Jaeckle arrived. This month we continued our studies of the effect of UV on the development of the sea urchin Sterechinus neumayeri. Adult sea urchins have been artificially spawned to initiate cultures of embryos that have been, to date, reared up to the pluteus stage in outdoor growth chambers under ambient light conditions. The effects of UV exposure on various developmental stages (zygotes, blastula, gastrula and plutei) have been investigated. Both outdoor ambient light experiments and dose responses with artificial light sources have been completed. A series of six outdoor incubations with cultures suspended at five depths from the surface to seven meters in the water column have been deployed on various time scales of 24 hours to 5-6 days. Observations include documentation and quantification of morphological changes, developmental delay, lethality and DNA damage induced by UV exposure. Work has also been continuing on monitoring temporal changes in the concentration of UV-absorbing compounds, mycosporine-like amino acids (MAAs), in different tissues (body, gonad, digestive tract and shell) of the limpet Nacella concinna. Nacella is a dominant shallow water species in the Palmer Station area and as such is exposed to the highest levels of UV exposure in the marine environment. Weekly intertidal collections of adults are being analyzed by HPLC for the quantification of specific MAAs (shinorine and porphyra-334). As expected from previous work, highest concentrations of MAAs are found in the ovaries. Ancillary collections of the red macroalga Iridea chordata are also being made once a week to determine if there is any correlation between MAA content of limpets and that of one of their potential food sources. HPLC analyses of I. chordata indicates the presence of at least four MAAs (mycosporine-glycine, shinorine. porphyra-334 and palythine). This monitoring program will help us to document the responses of Nacella to UV stress. During the past two weeks we have been able to spawn adult Nacella in the lab, although spawning in the field has not yet been observed. Cultures of embryos and larvae (up to the trochophore stage) have been initiated and are being maintained in outdoor tanks. Dose responses and in situ incubation experiments have been conducted as described above for Sterechinus to document and quantify morphological changes, developmental delay, lethality and DNA damage induced by UV exposure. A major effort this month has been to characterize the distribution and abundance of larval plankton in the water column relative to hydrographic conditions (temperature, salinity, light). Seacat CTD data (temperature, salinity and density) and Biospherical PUV data (UV and visible light) are being collected in conjunction with opening/closing net tows taken at several depths from the surface to 30 m. Maximum numbers of larvae have been collected mostly between 10 and 20 m depth. On several dates, large quantities krill were captured in the nets; however, larvae of a common sea star (Odontaster) and the pilidium larvae of nemertean worms continue to be the most abundant meroplankters. S-013 CHANGES IN ADELIE PENGUIN POPULATIONS AT PALMER STATION: EFFECTS OF LONG-TERM HUMAN DISTURBANCE AND ENVIRONMANTAL CHANGE. William R. Fraser, Montana State University Bozeman, MT. PERSONNEL ON STATION: Donna Patterson The conceptual model guiding this aspect of our research is described for S-035. Tourist distribution and abundance on Torgersen Island were documented through censuses during the month of December. Tourist censuses will continue until the end of the Adelie penguin breeding season at fledging, approximately February 28. Three ship visits were monitored during the month of December for a total of 232 tourists visiting Torgersen Island. Two of the three ship visits occurred during peak hatching of Adelie penguin eggs. Reproductive success sites were monitored daily to record hatch and loss dates at study nests; this information is vital in determining island and colony specific chronology of breeding efforts. Censuses of breeding pairs continued throughout the month at designated indicator colonies within the study area. Snow depth measurements also continued during December with the persistence of snowdrifts surrounding some colonies nearly one full month longer than in the 1996-97 season. LONG-TERM ECOLOGICAL RESEARCH ON THE ANTARCTIC MARINE ECOSYSTEM: AN ICE DOMINATED ENVIRONMNET The central hypothesis of the Palmer Long-Term Ecological Research (LTER) project is that the annual advance and retreat of sea ice is a major physical determinant of spatial and temporal changes in the structure and function of the antarctic marine ecosystem. Evidence shows that this dynamic variability of sea ice has an important, perhaps major, impact on all levels of the food web. LTER research is investigating hypotheses that sea ice is a major factor regulating seasonal primary production; the dynamics of the microbial loop and particle sedimentation; krill abundance, distribution and recruitment; and survivorship and reproductive success of apex predators. Two primary methods of sampling are used by the LTER to document interannual variability in the physical parameters and key biological components of the marine ecosystem: (1) An annual cruise that covers a large geographical area from Anvers to Adelaide Island and to 200 km offshore for a brief period from January to mid-February, and (2) an annual field season that samples the small geographical area within 3.5 km of Palmer Station, but for a longer time period covering the austral summer season from mid October through mid March. LTER components at Palmer Station during December were S-016, S-028, S-032 and S-035. S-016 LONG-TERM ECOLOGICAL RESEARCH ON THE ANTARCTIC MARINE ECOSYSTEM: AN ICE-DOMINANTED ENVIRONMENT (Phytoplankton Component). Maria Vernet, Scripps Institution of Oceanography PERSONNEL ON STATION: Wendy Kozlowski, Michael Crowder The group benefitted from the unusually pleasant weather the entire month and were able to easily collect water samples regularly through all of December. Full profile collections were done at Palmer Inshore stations E and B on December 1, 4, 9, 12, 15, 18, 23, 26 and 30, as well as a complete joint sampling at Station J with the ROZE on December 6. All water samples continue to be processed on station for pigments and productivity estimations, and preserved for later analysis for particulate carbon and nitrogen, nutrients, and microscopy. Preliminary estimations show average particulate carbon production integrated through 1% of surface PAR to be 1501 mgC/m2 and 1296 mgC/m2 at stations E and B, respectively, lower than the average production at this time one year ago. Non-quantitative net tows at all stations sampled show that the dominant phytoplankton species through the entire month has been the diatom Corethron. Preparations are also being made for the January LTER cruises on board the Abel J and LM Gould. S-028 LONG-TERM ECOLOGICAL RESEARCH (LTER) ON THE ANTARCTIC MARINE ECOSYSTEM: AN ICE-DOMINATED ENVIRONMENT (Prey Component). Langdon B. Quetin and Robin M. Ross, University of California, Santa Barbara PERSONNEL ON STATION: Langdon Quetin, Janice Jones (shared with S-032) Work continued to monitor krill abundance, growth and chemical composition in the vicinity of Palmer Station. During December we completed 6 acoustic transects from stations A-E and 4 acoustic transects from stations J-F. All acoustic problems are now solved, the last being a faulty DAT Recorder that was replaced with the spare old one. Krill continue to be abundant in the immediate vicinity of Palmer Station with both young-of-year and older stage classes present. Krill were caught weekly for length frequency analysis (5 tows), growth experiments (4 completed, 1 in progress), and frozen for anlaysis of lipid, protein, carbon and nitrogen (2 sets). Growth of krill in early December indicated a 40 day intermolt period, but three experiments in the middle of December indicated an 18-20 day intermolt period. The Abel J docked at Palmer Station December 28 and we were able to spend the afternoon planning for the LTER cruise that will start January 16. We would like to thank the captain and crew for their enthusiastic cooperation and willingness to make this cruise work. We would also like to thank Sheldon Blackman for his help in solving our acoustic problems and the continued support of the ASA staff. S-032 LONG-TERM ECOLOGICAL RESEARCH (LTER) ON THE ANTARCTIC MARINE ECOSYSTEM: AN ICE DOMINATED ENVIRONMENT (Modeling, Optical, Ice, Hydrography Component). Ray Smith, University of California, ICESS, Santa Barbara PERSONNEL ON STATION: Janice Jones (shared with S-028), Doug Conlin Sampling has continued at stations E and B on December 1, 4, 9, 15, 23 and 30. We did CTD and PRR casts and collected surace water samples for chlorophyll and salinity analyses. S-016 collected water samples from various depths for us at these stations as well. Samples were also collected from Bonaparte Point, Gamage Point and the seawater pumphouse on these dates for chlorophyll and salinity analyses. A partial run sampling at stations H and J was done on December 6, providing physical data to link with S-028 krill acoustics. CTD and PRR casts were done as well as surface water sampling for chlorophyll and salinity analyses. Complete runs consisting of stations E, H and J were done on December 12, 18 and 26. Salinity samples collected up to and including December 26 were analyzed using the Autosal on December 29. The fluorometer calibration has not been completed due to instrument malfunction. All data was successfully transferred to UCSB. S-035 LONG-TERM ECOLOGICAL RESEARCH (LTER) ON THE ANTARCTIC MARINE ECOSYSTEM: AN ICE-DOMINATED ENVIRONMENT (Seabird Component). William R. Fraser, Montana State University Bozeman, MT. PERSONNEL ON STATION: Peter Duley and Matt Irinaga A key assumption guiding LTER seabird research is that the persistence of any seabird population reflects the coincident availability of suitable nesting and foraging habitats. Variability in one or both of these habitats is thus viewed as being an important determinant of change in the magnitude and/or direction of seabird populations. LTER-related field work on Adelie Penguins encompasses three categories: breeding biology, foraging ecology and demography. Reproductive success sites on Torgersen and Humble Islands were monitored daily to obtain hatch and loss dates. Hatching appears to be highly asychronous within the study area. Censuses of breeding pairs on a subset of colonies continued throughout the month in conjunction with research objectives for S-013. Colony size, aspect, and snow accumulation may be strongly influential this season on breeding success and demography of Adelie penguins. The Humble Island Remote Data Link was restored by Sheldon Blackman; testing of remote data retrieval was completed. Transmitters will be deployed within the first few days of January to coincide with the onset of stomach lavage as part the CCAMLR Ecosystem Monitoring Program protocols. Baseline breeding and population data on other area seabirds were, as in the past, obtained opportunistically to maintain continuity in long-term databases. Brown and South Polar skuas, Cormorants, Giant Petrels and Kelp Gulls are the focus of these efforts. Nesting efforts of South Polar skuas are somewhat late this year with only five active nests on Shortcut Island at present. Several adult South Polar skuas that were banded as chicks on Shortcut Island have been resighted; band reading efforts will continue as time allows throughout the season. The main Blue-eyed shag colony on Cormorant Island is now completely extinct. Breeding population levels of the other two sub-colonies are monitored periodically. Southern Giant Petrel nests in the study area have been surveyed and the number of breeding pairs is significantly lower than during the 1996-97 season. Monitoring of marine mammals was continuous throughout the month of December. During the last two weeks of the month, inshore feeding of crabeater seals, humpback whales and seabirds was observed often. Observations on envionmental conditions were recorded daily. We would like to thank the Palmer Station staff for continued support during the month of December with special thanks to Randy Sliester for excellent boating support and Sheldon Blackman with continued assistance during daily radio operations. S-085 GPS CONTINUOUS OPERATION REFERENCE STATION. J. Mullins, U.S. Geological Survey PERSONNEL ON STATION: Kevin Bliss (ASA science technician) For the month of December, GPS data was collected nearly continuously. Daily data was converted to a RINEX format, compressed, and FTPed to Reston, VA. The average daily data transfer to Reston was 2.65 MB. On December 4, the serial communications between the Z-12 receiver and PC became garbled. A large number of error messages were being generated, and a reset of both the receiver and the GPS-Base software was required to clear the problem. During this time, data collection was interrupted from 0005 UT until 0020 UT. On December 11, the baud rate on the PC's serial port was increased from 19200 to 38400. All other CORS operations were normal for the month of December. S-091 GLOBAL SEISMOGRAPH STATION AT PALMER STATION. R. Butler, Incorporated Research Institutions for Seismology (IRIS) PERSONNEL ON STATION: Kevin Bliss (ASA science technician) Operations continued without interruption throughout the month. S-106 STUDIES OF LIGHTNING-INDUCED ELECTRON PRECIPITATION OF THE IONOSPHERE. U. Inan, Stanford University PERSONNEL ON STATION: Kevin Bliss (ASA science technician) Throughout the month of December, the nightly narrowband data collection was plagued by frequent truncation of the recording session. For the month, 16 of 31 narrowband recordings were shorten sessions. Early in the month, tests were performed to determine if the 0000 UT HF or HAM radio operations might be responsible, but the results were inconclusive. To eliminate one of the suspected causes, the 0000UT HF radio operations, the start time of the narrowband recording was moved from 0000 UT to 0100 UT. Additionally, a proper log of HAM operations was not being maintained, so a log was started to look for a correlation between the late night HAM radio operations and the truncated data sessions. As of this writing, more data was needed, but it looked as if a pattern between the HAM radio operations and shortened session was appearing. The HAM radio had been a prime suspect, as the location of the transmitter had recently been moved nearer to the VLF equipment. S-204 MEASUREMENTS OF ATMOSPHERIC O2 IN RELATION TO THE GLOBAL CYCLE. Ralph Keeling, Scripps Institution of Oceanography PERSONNEL ON STATION: Jim Litch (ASA physician) Air samples are collected on a semi-weekly basis. The samples are shipped to Scripps for analysis of O2 and CO2 content. The goal of the program is to resolve seasonal and interannual variations in atmospheric O2 (detected through changes in O2/N2 ratio) which can aid in the determination of rates of marine biological productivity and ocean mixing and aid in the separation of the global sink for anthropogenic CO2 into terrestrial and oceanic components. The program involves air sampling at a network of sites in the Northern and Southern Hemispheres. Palmer Station is especially well situated to resolve signals due to carbon cycling in the Southern Ocean. S-254 CHLORINE-AND BROMINE-CONTAINING TRACE GASES IN ANTARCTICA. R.A. Rasmussen, Oregon Graduate Institute for Science and Technology PERSONNEL ON STATION: Jim Litch (ASA physician) The samples are returned to the Institute for analysis of a number of trace components, especially chlorine- and bromine-containing gases. These elements have been implicated in the chemical processes that contribute to the austral-spring depletion of the ozone layer over Antarctica. This work will contribute to a better understanding of the buildup of trace constituents, particularly those of high-latitude marine origin. S-257C COLLECTION OF ATMOSPHERIC AIR FOR THE NOAA\CMDL WORLDWIDE FLASK SAMPLING NETWORK. James T. Peterson, Environmental Research Laboratories, National Oceanic and Atmospheric Administration PERSONNEL ON STATION: Jim Litch (ASA physician) The National Oceanic and Atmospheric Administration (NOAA) Climate Monitoring and Diagnostics Laboratory team continue long-term measurements of trace atmospheric constituents that influence climate. The Palmer Station air samples are returned to the NOAA laboratory for analysis of trace constituents, including carbon dioxide. These measurements are part of NOAA's effort to determine and assess the long-term buildup of global pollutants in the atmosphere. These data will be used to determine how the rate of change of these parameters affects climate, particularly by including them in climate model studies. S-275 UM/DOE-EML REMOTE ATMOSPHERIC MEASUREMENTS PROGRAM. C. Sanderson, Department of Energy, Environmental Measurements Laboratory PERSONNEL ON STATION: Kevin Bliss (ASA science technician) One sample filter was exposed for the duration of each week, and a weekly schedule of calibration, background, and sample counts was maintained. T-312 TERASCAN SATELLITE IMAGING SYSTEM. R. Whritner, Scripps Institution of Oceanography PERSONNEL ON STATION: Kevin Bliss (ASA science technician) On December 3, the Palmer Station TeraScan system successfully downloaded and processed its first SeaWiFS pass from the new ORBVIEW-2 satellite. Throughout the month of December, the TeraScan system collected, archived, and processed DMSP, NOAA, and ORBVIEW-2 telemetry, maintaining a schedule of 18-20 passes per day. NOAA, DMSP, and ORBVIEW-2 telemetry were archived for S-032 when the LTER grid was clear. AWS transmissions were monitored from Bonaparte Point, Hugo Island, and RACER Rock. During the month, preparations began for the Solaris 2.6 OS upgrade. T-513 UV MONITORING NETWORK. C. Booth, Biospherical Instruments, Inc. PERSONNEL ON STATION: Kevin Bliss (ASA science technician) Throughout the month, raw irradiance data were collected daily and transmitted to BSI, and preliminary irradiances and integrals were produced in support of Science. Scheduled absolute calibration scans were performed on December12 and December 17. On December 18, several peck marks, apparently from sheathbills, were noticed on the UV Monitor's Teflon collector. On December 18, the SyQuest data disk overfilled, causing a gap in data between 0600 UT and 1530 UT.