SCIENCE SITREP JUNE 2000 GO-052-P GPS CONTINUOUS OPERATION REFERENCE STATION. J. Mullins, U.S. Geological Survey The station science technician has monitored the system. During the month, GPS transmissions were collected continuously, converted daily to a RInEx format, compressed, and transmitted to the US Geological Survey in Reston, VA. GO-090-P GLOBAL SEISMOGRAPH STATION AT PALMER STATION. R. Butler, Incorporated Research Institutions for Seismology (IRIS) The station science technician has monitored the system. Global seismic events were recorded throughout the month. A planned power outage on 20 June disabled the link between the DA and DP, but both computers continued to operate throughout the outage, and buffered data was properly transmitted when power was restored. AO-106-P STUDIES OF LIGHTNING-INDUCED ELECTRON PRECIPITATION OF THE IONOSPHERE. U. Inan, Stanford University The station science technician has monitored the system. The Stanford receiver records very low frequency (VLF) radio waves for studying ionospheric and magnetospheric natural phenomena. At the request of the grantees, the alignment of the heads on the Ampex tape drive was checked and adjusted. This adjustment dramatically altered the high frequency performance of the drive. After the alignment was set, the playback, input, and record levels were also adjusted. "Before and after" digital images of the heads were supplied to the grantees, as were spectrograms from the broadband digital acquisition system demonstrating that the line receiver filters are not active. Powering the VLF equipment from a portable generator during a planned power outage on 20 June introduced a slightly elevated level of 60 Hz "hum" to the signal, which affected four synoptic recordings. No synoptics were missed. The messenger cable on the upper half of the glacier cable run was tightened to minimize the risk of a drooping signal cable freezing into the glacier. OO-204-O MEASUREMENTS OF ATMOSPHERIC O2 IN RELATION TO THE GLOBAL CARBON CYCLE. Ralph Keeling, Scripps Institution of Oceanography Air samples are collected on a semi-weekly basis by the station physician. The samples are return 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. OO-254-O CHLORINE-AND BROMINE-CONTAINING TRACE GASES IN ANTARCTICA. R.A. Rasmussen, Oregon Graduate Institute for Science and Technology 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. OO-264-O COLLECTION OF ATMOSPHERIC AIR FOR THE NOAA\\CMDL WORLDWIDE FLASK SAMPLING NETWORK. James T. Peterson, Environmental Research Laboratories, National Oceanic and Atmospheric Administration 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. This data will be used to determine how the rate of change of these parameters affects climate, particularly by including them in climate model studies. OO-275-O DOE-EML REMOTE ATMOSPHERIC MEASUREMENTS PROGRAM. C. Sanderson, Department of Energy, Environmental Measurements Laboratory The station science technician has operated the system. One sample filter was exposed for the duration of each week, and a weekly schedule of calibration, background, and sample counts was maintained. The RAMP system is part of a global network seeking to characterize the quantity and distribution of radionuclide particles occurring both naturally and artificially in the atmosphere. The pump was off for approximately 90 minutes while a portable generator was operating near the intake stack to provide power during a planned power outage on 20 June, but all counting electronics remained powered throughout the outage. OO-283-P ANTARCTIC AUTOMATED WEATHER STATIONS. Charles Stearns, University of Wisconsin The station science technician has monitored the local sites. Automated Weather Station (AWS) transmissions were monitored from Bonaparte Point, Hugo Island, and RACER Rock using the TeraScan system. The Bonaparte Point unit continued to send an invalid wind speed, presumably due to a CPU failure. TO-312-O TERASCAN SATELLITE IMAGING SYSTEM. R. Whritner, Scripps Institution of Oceanography The station science technician has operated the system. Throughout the month, the TeraScan system collected, archived, and processed DMSP and NOAA satellite pass telemetry, maintaining a schedule of 18-23 passes per day. NOAA and DMSP telemetry were archived for BP-032-O when the LTER grid was clear of clouds. 85 GHz SSM/I ice concentration images were produced and sent to BP-032-O on a weekly basis. TO-513-O UV MONITORING NETWORK. C. Booth, Biospherical Instruments, Inc. The station science technician has operated the system. Throughout the month, raw irradiance data scans were collected daily and transmitted to BSI, and preliminary irradiances and spectral integrals were produced in support of Science. Absolute calibration scans were performed as scheduled. Sections of the yearly network operations reports were reviewed, and comments were provided to the investigators.