PALMER STATION SCIENCE SITREP MAR 1996 The following science projects were active at Palmer Station during the month: S-030 THERMAL ADAPTATION IN POLAR MACROALGAE. Ian Davison, University of Maine, Orono, ME 04469-5722, Ken Dunton, University of Texas at Austin, Port Aransas, TX 78373-1267, and Val Gerard, State University of New York, Stony Brook, NY 119794-5000. PERSONNEL ON STATION: Ian Davison, Ken Dunton, Val Gerard and John Heine. Our research focused on the physiology of sporophytes of the giant endemic Antarctic brown macroalga Himantothallus grandifolius and has involved both field and laboratory studies. Most of our work focused on a population growing between 8-12 m at Hermit Island, with a secondary site being the wreck of the Bahia Paraiso. One of our primary objectives was to collect juvenile Himantothallus to take to Maine, New York and Texas for more detailed experiments. We collected approximately 200 individuals, 5-20 cm in length, mostly from the Bahia. The ship was densely settled by young recruits, suggesting that Himantothallus rapidly colonizes bare substrate such as areas denuded by ice scour. Another reason for examining the plants on the Bahia, which sank in 1989, was to allow us to estimate the possible age and growth rate of Himantothallus. Although this species reaches 17 m in length, little is know about it's longevity or growth rate. The largest alga found on the wreck was 4.5 m long, suggesting not only that growth rates are reasonably high, but that the largest seaweeds found in nature may be many years old. Two light meters were deployed at Hermit Island to record the annual irradiance received by the Himantothallus population. In addition, 25 large, adult algae were tagged and hole-punched to allow us to estimate annual productivity when we return in 1997. Most of our physiological experiments used algae between 20-30 cm in total length which is the maximum size that can conveniently be cultured in the laboratory with adequate replication. Preliminary experiments compared the photosynthetic - irradiance responses of entire algae 50 cm in length (measured under natural light in 5 L chambers) with those of small (3 cm2) disks excised from the blade of the same plant (measured in 10 mL of water in light from a tungsten filament bulb). The results indicated close correspondence between the two sets of measurements, giving us confidence that studies with excised disks provide a good indication of the responses of entire plants. Subsequent experiments with entire plants incubated in large outdoor tanks (inoculated with C-13 labelled bicarbonate) under ambient conditions were performed to measure light independent carbon fixation (an important pathway in brown algae), and nitrate uptake rates (using N-15), and to investigate the possibility that long distance translocation from the older blade tissue to the basal meristem may be important in the overall carbon and nitrogen budgets of large Himantothallus. The primary focus of our laboratory experiments was thermal acclimation of the photosynthetic apparatus. Seven replicate algae were grown in tanks filled with 20 L of aerated seawater and illuminated at a photon flux density of 80-90 umole/m2/s in a 16:8 L:D cycle at -2, 0, 5, 10 and 15C. Maximum growth rates occurred at 5C. Rates of dark respiration and light-saturated photosynthesis (Pmax) were inversely proportional to growth temperature when assayed at a standard temperature of 10C. However, rates were similar in all treatments when measured at the growth temperature. This metabolic compensation was associated with, and possibly attributable to, changes in enzyme activities. Activities of the Calvin cycle enzymes ribulose-1, 5-bisphosphate carboxylase oxygenase (Rubisco) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) were also inversely proportional to growth temperature when assayed at 20C, but were similar when measured at the respective growth temperatures. Examination of the thermal characteristics of GAPDH indicated that changes in the apparent activation energy occurred at lower temperatures than in temperate algae, suggesting the possibility of cold-adaptive isozymes in Himantothallus. The results of the growth experiments are interesting, because they indicate that Himantothallus has the ability to acclimate to temperatures well outside the range experienced in nature. Similar thermal acclimation of enzyme activities occurs in temperate macroalgae such as the brown alga Laminaria saccharina. However, in contrast to Laminaria, Himantothallus did not exhibit thermal acclimation of pigment content, light harvesting efficiency, quantum yield or the ratio of variable to maximum fluorescence. We suggest that this is a consequence of the selective pressure exerted by the low-light environment inhabited by Himantothallus which has favored the maintenance of maximum light harvesting efficiency regardless of changes in temperature. Overall, we believe our 1-month stay at Palmer has been highly productive and very successful. This is in no small measure due to the excellent support we have received from all of the ASA employees on station, for which we are very grateful. S-013 SEABIRD INVESTIGATIONS AT PALMER STATION AS PART OF THE NMFS/AMLR ECOSYSTEM MONITORING PROGRAM. William R. Fraser, Montana State University, Bozeman, MT. 59717 See S-045F S-045F LONG-TERM ECOLOGICAL RESEARCH (LTER) ON THE ANTARCTIC MARINE ECOSYSTEM: AN ICE-DOMINATED ENVIRONMENT (SEABIRD COMPONENT). William R. Fraser and Wayne Z. Trivelpiece, Montana State University, Bozeman, MT. 59717 PERSONNEL ON STATION: Eric Holm, Bill Fraser and Donna Patterson. March activities focused on the completion of this season's component of the long-term giant petrel (Macronectesgiganteus) banding program, marine mammal census, and the monitoring of the south polar skua (Catharacta maccormicki) breeding success. We banded 223 giant petrel chicks this month which brought the season total to 367 chicks. This number suggests that populations of this species are currently stable in the Palmer Station area. Field work also concentrated on the completion of the breeding success study of the south polar skuas on Shortcut Island. This was a banner year for south polar skuas with 72 pairs arriving and attempting to breed on Shortcut. The net total of chicks produced was fifty one, fifty of which were banded (in marked contrast to last year's breeding season which produced no chicks at all). A preliminary census of the area fur seal population shows a major reduction in numbers. As of this writing there seems to be at least 50% less fur seals in the area as compared to this time last season. Bill Fraser and Donna Patterson departed Palmer on March 6 leaving Eric Holm to complete the field work until his departure on March 26. ASA, namely Frank Ball the boating coordinator, played a major role for a successful season completion by providing boat shuttles in order to make island visits possible. S-045R LONG-TERM ECOLOGICAL RESEARCH ON THE ANTARCTIC MARINE ECOSYSTEM: AN ICE-DOMINATED SYSTEM. Robin M. Ross and Langdon B. Quetin, University of California, Marine Science Institute, Santa Barbara, CA 93106. Personnel on station: Janice Jones (shared position with S-045S), Trent Taylor and Christy Lewis). Standard tows were completed at stations A-B, I-J on 1 Mar, and at D-E, F-G on 2 Mar. A full set of tows at all 4 stations was completed on 15 Mar. Unsuccessful krill searches (4 hour average search time) were conducted on 2 Mar, 5 Mar, 14 Mar and 15 Mar. On 9 Mar we caught krill, started a growth experiment, and did a length frequency analysis. On 18 Mar we caught a small number of krill, some of which we used for chemical composition/condition factor analyses which are done on frozen samples back in Santa Barbara, the rest were used in a length frequency analysis. Our last krill search was conducted on 20 Mar and yielded enough animals to do an IGR (growth experiment), cc/cf frozen samples, and a length frequency analysis. Our standard acoustics transect from A-E was successfully completed on 12 Mar and 18 Mar. On 11 Mar we had some minor problems due the equipment being very damp after several days of rain and the transect was only completed from A-C. The transect from F-J was completed successfully 08 Mar, 13 Mar and 19 Mar. The trawl zodiac, Kriller/Rubber Duke, was removed from the water 20 Mar and disassembled 21 Mar. Packing, inventory and retrograding of gear was done from 21 Mar - 25 Mar. As the season comes to a close, S045R would like to thank ASA for their support during the season. Thanks go to Herb Baker for his superb effort as boating coordinator and to cmdr for all his help with designing and setting up the new console in the trawl zodiac. Thank you all again for helping to make the season a successful one. S-045S LONG-TERM ECOLOGICAL RESEARCH (LTER) ON THE ANTARCTIC MARINE ECOSYSTEM: AN ICE DOMINATED ENVIRONMENT. Ray Smith, University of California at Santa Barbara, ICESS, Santa Barbara, CA 93106 Personnel on Station: Janice Jones (shared position with S-045R), and Karen Fisher. Chlorophyll, salinity, CTD and PRR samples were completed successfully at B through E on 5 Mar, 12 Mar and 18 Mar. Water collected by S045V on these dates was processed for chlorophyll and salinity. Successful runs at stations F through J were completed on 8 Mar, 13 Mar and 19 Mar. Water collected by S045V on 8 Mar and 15 Mar was processed for chlorophyll and salinity. The optics zodiac, ROZE, was pulled from the water on 19 Mar and was disassembled 20 Mar. Inventory of gear remaining at Palmer Station over the winter and packing of retro gear was done from 21 - 26 Mar. The research vessel R/V POLAR DUKE took a small crew to Hugo Island on 23 Mar to attempt replacement of the seawater temperature probe. Bad weather and seas led to an abort of the effort. The R/V POLAR DUKE returned to Palmer Station on 23 Mar and elected to try the Hugo Island repair a second time on 24 Mar. Again, weather and rough seas halted the attempt. The ship remained on site at Hugo Island through the night to make a third attempt on the morning of 25 Mar. The weather was not favorable and the R/V POLAR DUKE returned to Palmer Station. S-045S would like to thank Greg Packard and Kevin Bliss for their efforts in these attempts. Now that the packing is finished and S-045S is ready to depart, I would like to thank ASA staff on station for making this season a successful one. Thank you to InfoSys for their extra efforts in getting our data FTP'd off station and to cmdr for his help with the blueprints. Hope to see you in October. S-045V LONG TERM ECOLOGICAL RESEARCH (LTER) ON THE ANTARCTIC MARINE ECOSYSTEM: AN ICE DOMINATED ENVIRONMENT. PHYTOPLANKTON COMPONENT. Maria Vernet, Scripps Institution of Oceanography, Marine Research Division, La Jolla, CA 92093-0218. PERSONNEL ON STATION: Wendy Kozlowski, Karie Sines, Andrew Greaves During the month of March, five full standard water sampling runs from station E to B were completed. These water collections from the Legend were on the 8th and 15th; sampling on the 5th, 12th and 18th coincided with CTD/PRR runs with S-045S's group on the ROZE. The NSF representative on station at the time, Carol Roberts, accompanied us on the 5th to stations E and D to get a feel for some of the zodiac work done at Palmer station. On all days, water was collected for chlorophyll determination by fluorometry and salinity determinations for S-045S, as well as for HPLC determination of pigments, particulate carbon and nitrogen level measurements, productivity (as measured by carbon uptake) experiments, nutrient analysis, and microscopy sample preservation for S-045V. Water collection at station B for growth rate experiments also occurred on the 9th, 13th and 19th. Analysis on all samples from the 95-96 season were completed for both nutrients and pigments, and all simulated in situ and photosynthesis versus irradiance experiments were completed for the season and data processing continued for all parts of the project. Preliminary work for fifth channel ammonia analysis also continued through the month. The last week on station was spent doing inventory and packing for the close of the 1995-1996 season. S-045V would like to thank ASA for all the support and help throughout the season. S-091 PALMER IRIS SEISMOLOGY. R. Butler, U.S. Geological Survey, Seismological Laboratory, Albuquerque, NM. 87115 No personnel were on station. The system has been monitored by the station science technician. On 11 March, the aqcfg file was edited to correct the sample rate on the AFP packets and remove printer messages regarding AFP gaps. All other USGS operations were normal for the month of March. S-106 VERY LOW FREQUENCY (VLF) REMOTE SENSING OF THUNDERSTORM AND RADIATION BELT COUPLING TO THE IONOSPHERE. U. Inan, Stanford University, STARLab, Stanford, CA 94305 Personnel on station: Sean Lev-Tov On February 28 Sean Lev-Tov arrived on site for yearly maintenance and calibration work on equipment. Continuous broadband recording VCR's were cleaned inside. Backup battery of programmer clock was replaced. Ampex recorder (for synoptic recordings with AGO's) was taken off-line on March 6. Failed lights for displays were replaced, capstan motor was replaced, reel idler assembly was replaced, brake tension and torque of take-up motors were checked and found to be acceptable, microphone connection to jack was resoldered, record and reproduce heads were replaced, tape path was cleaned, and complete mechanical and electronic calibrations and adjustments were made. Channel 3 of Ampex was not functioning properly and was boxed for shipment to Stanford for repairs. Ampex is now working in synchronization with AGO stations for broad band recordings. Annual adjustment of frequency standard was performed. Ground cable to sea was inspected and found to be in excellent condition. All antenna feed line posts had melted out and fallen over; they were taken from glacier, painted white, and drilled into the glacier. The feed line was raised up onto the posts. On March 7 high winds toppled the antenna. Work was done to sink guy posts, build a new lean plate, and anchor the base with a new base board to the glacier. On March 12 the antenna was raised with 16 people. Final guying of tower was complete March 14. On March 22 final adjustments to magnetic loops were made. S-254 CHLORINE-AND BROMINE-CONTAINING TRACE GASES IN ANTARCTICA. R.A. Rasmussen, Oregon Graduate Institute for Science and Technology, Portland, OR 97291 No personnel were on station. Air samples are taken on a weekly basis by the station 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. J.T. Peterson, Environmental Research Laboratories, National Oceanic and Atmospheric Administration, Boulder, CO 80303-3328. No personnel were on station. Air samples are taken on a weekly basis by the station 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 (RAMP). J. Prospero and T. Snowdon, University of Miami; C. Sanderson and N. Chui, EML/DOE N.Y. 10014 No personnel were on station. The system has been operated by the station 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. On 18 March, the system clock was set back one hour as Palmer Station went off daylight savings time. T-312 TERASCAN SATELLITE IMAGING SYSTEM. R. Whritner, Scripps Institute of Oceanography, La Jolla, CA. 92093-0218 No personnel were on station. The system has been operated by the station science technician. The TeraScan system collected, archived, and processed DMSP and NOAA telemetry, maintaining a schedule of 15-17 passes per day. DMSP telemetry was archived for S-045S, and AWS data was collected from the Hugo Island and Bonaparte Point automatic weather stations in support of the LTER project. Throughout the month, 85 GHz SSMI data was collected from the F-10 spacecraft and provided to Bob Whritner in support of the R/V Nathaniel B.Palmer's operations in the Amundsen Sea. On 19 March, the TeraScan software upgrade, version 2.6, was installed on the Sun SPARCstation 10. As of this writing, the TeraScan was still running version 2.4, pending testing of the new software. T-513 UV MONITORING EXPERIMENT. C. Booth, Biospherical Instruments, Inc., 5340 Riley Street, San Diego, CA 92110-2621 Personnel on station: Jim Ehramjian The system has been operated by the science technician. Throughout the month, raw irradiance data were collected daily and transmitted to BSI. Preliminary irradiance data and inferred ozone abundances were produced in support of Science. On 13 March, the 0900 data scan was removed from the schedule. On 19 March, Jim Ehramjian arrived on station to perform the annual site visit. Data collection was halted on 21 March to allow for inspection, maintenance, and calibration of the instrument. 04204744.263 PLM222.APR