PALMER STATION SCIENCE SITREP JAN 1996 The following science projects were active at Palmer Station during the month: S-003 OZONE DEPLETION, UV-B RADIATION AND VASCULAR PLANT PERFORMANCE IN ANTARCTICA. Thomas Day, Arizona State University, Tempe, Arizona, 85287. PERSONNEL ON STATION: Thomas Day, Carl Grobe, Christopher Ruhland. We are conducting our main experiment on the Stepping Stones where we have about 80 radiation exclusion frames in place over existing vegetation. We are using the frames to hold filters that exclude UV-B radiation, or UV-A and UV-B radiation, and also raise temperatures around vascular plants (Antarctic hairgrass, Deschampsia antarctica; Antarctic pearlwort, Colobanthus quitensis). The frames and filters continue to hold up to the rigors of Antarctic weather very well, and continuous monitoring of microclimate under the different treatments confirms that our filter frames are providing the desired modifications. Tentative analyses suggests that our warming treatments increase air temperatures at plant height by about 0.5 C on cloudy days and 3 C on sunny days over the 0500 to 2000 hr "day time" period. Following collection of baseline data in November and December, we have been concentrating on assessing treatment effects on plant physiological performance. To date our findings suggest plants perform the best (have the highest photosynthetic rates) on cooler days, when air temperatures are less than 15 C. This led us to the question of whether high light or warm temperatures were depressing photosynthesis on warm (typically sunny) days. We assessed this question by potting wild plants and bringing them into the lab were we could assess photosynthetic responses under tightly controlled environmental conditions. A temperature controlled gas-exchange chamber along with light filters allowed us to determine the photosynthetic response of these plants to light level and temperature. This work on Deschampsia strongly infers that it is higher air temperatures (> 15 C), not high light, that depress photosynthesis on warm, sunny days. Additional investigations showed that dark respiration does not fully account for plants' poor photosynthetic performance at high temperatures. Similar lab work characterizing the photosynthetic responses of Colobanthus is in progress. Another field finding is that plants under our warming treatments have substantially higher photosynthetic rates than plants under ambient temperatures. The exception to this occurs when ambient air temperatures are already near or above the 15 C threshold, which is fairly uncommon (ie. warm sunny days). A third finding from our field experiments is that flower production and development is enhanced under our warming treatments. Warming treatments lead to substantially higher flower production in Colobanthus and the developmental stage of flowers in both Colobanthus and Deschampsia are much further along than in their counterparts under ambient temperatures. Even though this month was a very busy one for the station due in part to the departure of the Polar Duke on a research cruise, ASA and other science personnel continued to provide us with excellent, timely support and useful suggestions throughout. S-013 CHANGES IN ADELIE PENGUIN POPULATIONS AT PALMER STATION: THE EFFECTS OF LONG-TERM HUMAN DISTURBANCE AND ENVIRONMENTAL CHANGE. William R. Fraser, Montana State University, Bozeman, Montana 59717. See S-045F. S-019 REPRODUCTIVE ENDOCRINOLOGY OF FREE-LIVING ADELIE PENGUINS AT TORGERSEN ISLAND, ANTARCTICA. Carol Vleck, Iowa State University, Ames, IA 50011. PERSONNEL ON STATION: Carol Vleck (through 17 DEC), Theresa Bucher, Wendy Reed, Asrun Krismundsdottir During January 1996 we continued our collection of blood samples from adult Adelie penguins on Torgersen Island (both successful and failed breeders). We sampled birds in attendance at the nest sites through the brood/guard stage and began sampling adults returning to feed chicks in the creche stage. Also, we began banding, weighing and measuring, and taking blood samples from molting chicks. We completed the serial bleeding of single birds (for the analysis of stress-associated hormone levels) during both the brood/guard stage and the creche stage on Torgersen, Christine and Dream Islands. In total over 250 blood samples were collected. We continued to census our study colonies on Torgersen daily, and sometimes twice a day, as birds were absent for a greater proportion of the time. Access to Torgersen was not possible due to inclement weather (high winds) on only two days of the month. During visits to the colonies by tourist groups we maintained a presence to insure minimum disruption to the colonies and be available to answer questions that the visitors might have, either about the birds or about the scientific studies underway. S-045F LONG TERM ECOLOGICAL RESEARCH PROJECT (LTER) ON THE ANTARCTIC MARINE ECOSYSTEM: AN ICE DOMINATED ENVIRONMENT (SEABIRD COMPONENT). William R. Fraser/Wayne Z. Trivelpiece, Montana State University, Bozeman, Montana 59717. PERSONNEL ON STATION: Bill Fraser, John Carlson, Eric Holm, Karen Carney, Donna Patterson Our research at Palmer Station, initiated in October, continued during the month of January with minimal loss of time due to weather (approximately 3 days). Access to nearby islands during the month of January was not affected by pack ice. Studies on Adelie penguin reproductive success at sites on Torgersen Island were completed by 13 January coincident with creching. Initial examination of reproductive success between tourist and control sites reveals little difference in productivity (1.34 versus 1.48 chicks per pair, respectively). Six tour ships and two yachts visited Torgersen Island during the month of January. Approximately 600 tourists visited the penguin colonies open to tourism; a three-fold increase over January 1994 during which several visits were canceled due to poor weather. Routine censusing of adelie colonies were performed throughout the month and will continue until fledging. Thirty-four transmitters were deployed on 9 January for determination of foraging trip duration. A solar-powered remote data retrieval system installed by Jim Hamlin has been instrumental in downloading foraging data without interruption of telemetry operations. Adelie penguin diet sampling commenced on 11 January in support of AMLR and LTER programs; twenty-five samples have been collected to date. Euphausia superba present in samples mainly consists of large females and juveniles less than 35 mm in length. Thysanoesa macrura has only been present in 24% of the samples suggesting elevated availability of E. superba as compared with samples during the 1994-95 season. Nearly 50% of these samples have contained fish. Both diet sampling and telemetry efforts will continue through mid-February. South Polar and Brown skua reproductive sites continue to be monitored on five day intervals on three islands to determine hatching dates, chick growth rates and diet composition. Brown skua productivity is extremely low this year with only four pairs out of ten remaining active at this writing. Banding of adult South Polar skuas on Shortcut Island began on 27 January; chick banding is expected to begin during the next two weeks. All-island nest checks of Southern Giant Petrels was completed on 10 January; total breeding population shows a slight increase over last season with approximately 430 pairs present. Monitoring of Blue-eyed shag colonies on Cormorant island continues; declines of 75-90% have been recorded since their pre-Bahia Paraiso oil spill population of 800-1000 breeding pairs. Collection of cormorant reproductive success data as well as diet information (i.e., boli) continued throughout the month of January and the surviving chicks have progressed into the creche phase. Monitoring of marine mammals continues on all islands. We would like to thank the Palmer Station staff for continued support during the month of January, especially Brian Williams, Dave Bell and Greg Schaffer for assistance with the remote data system and maintenance of excellent radio communications. Also special thanks to Herb Baker for outstanding boating support. William Fraser arrived on station 06 January. Karen Carney departed Palmer Station on 08 January to lead the seabird component of the LTER cruise. S-045R LONG-TERM ECOLOGICAL RESEARCH (LTER) ON THE ANTARCTIC MARINE ECOSYSTEM: AN ICE-DOMINATED SYSTEM. Robin M. Ross and Langdon B. Quetin, University of California, Marine Science Institute, Santa Barbara, California 93106. S-045S LONG-TERM ECOLOGICAL RESEARCH (LTER) ON THE ANTARCTIC MARINE ECOSYSTEM: AN ICE DOMINATED ENVIRONMENT. Ray Smith, University of California, ICESS, Santa Barbara, CA 93106. S-045V LONG-TERM ECOLOGICAL RESEARCH (LTER) ON THE ANTARCTIC MARINE ECOSYSTEM: AN ICE-DOMINATED ENVIRONMENT (PHYTOPLANKTON COMPONENT). Maria Vernet, Scripps Institution of Oceanography. PERSONNEL ON STATION: None. All personnel for these three groups are on board the R/V POLAR DUKE. S-091 PALMER IRIS SEISMOLOGY. R. Butler/G. Holcomb, U.S. Geological Survey, Albuquerque, NM. No personnel were on station. The DP computer was off for the duration of a scheduled power outage on 05 January, from 1620 to 2245 GMT. Twice during the month of January, the DP reported a read error while verifying data on the tape; automatically switching to the other tape drive unit. S-106 VERY LOW FREQUENCY (VLF) REMOTE SENSING OF THUNDERSTORM AND RADIATION BELT COUPLING TO THE IONOSPHERE. U. Inan, Stanford University. No personnel were on station. On 01 January, the Stanford Programmer clock was retarded by one second to stay in sync with the New Years time adjustment on the GOES satellite. The VLF system was switched over to generator power during a scheduled power outage on 05 January. While on the generator, approximately three hours of synoptic recordings were missed when the battery backup failed during the transfer to generator power. The problem was later traced to a faulty battery and an improperly configured switch. S-254 CHLORINE- AND BROMINE-CONTAINING TRACE GASES IN ANTARCTICA. R.A. Rasmussen, Oregon Graduate Institute for Science and Technology, Portland, Oregon, 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. James 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. J. Prospero/T. Snowdon, University of Miami; C. Sanderson/ N. Chui, EML/DOE N.Y. No personnel were on station. The air pump was off for the duration of a scheduled power outage on 05 January, from 1620 to 2245 GMT. Once power was restored, the MCA high voltage was turned back on and background counting was restarted. All other DEAN/RAMP operations were normal for the month of January. T-312 TERASCAN SATELLITE IMAGING SYSTEM. R. Whritner, Scripps Institute of Oceanography, La Jolla, CA. No personnel were on station. Throughout the month, 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 satellite imagery was provided to the R/V POLAR DUKE during the LTER Cruise. Additionally, AWS data was collected from the Hugo Island automatic weather station in support of the LTER project, and troubleshooting was performed on the failed Bonaparte AWS. During the month, the ongoing problem with the Sun SPARCstation hanging in the middle of the night continued. In an effort to reduce the amount of data lost during these occasional crashes, the General Assistants began monitoring the TeraScan while on their nightly rounds. The night watch proved very successful, and several problems were caught before an appreciable amount of data was lost. T-513 UV MONITORING EXPERIMENT. C. Booth, Biospherical Instruments, Inc. No personnel were on station. Preliminary irradiances, integrals, and deduced ozone abundances were calculated on a daily basis in support of science. Absolute calibration scans were performed using the site standard and seasoned lamps. On 24 January, the 0600 GMT data scan was removed from the schedule. The UV Monitor was powered by a generator during a scheduled power outage on 05 January, from 1620 to 2245 GMT. No scans were missed. During the second half of the month, the upper box temperature was alarming on a high temperature indication during response and multiwavelength scans. Moving the Fuji roof box temperature sensor to a location higher in the roof box ultimately corrected the problem. Multiple AXSS communication errors were noted throughout the last week of the month of January. 07013642.607 PLM457.FEB