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This paper focuses on the first year-round observations of surface mass balance, sublimation and snow temperatures at Dome Fuji Station. This station was newly established at the highest point (77°19′01″S, 39°42′12″E; 3810m) in Queen Maud Land, Antarctica by the Japanese Antarctic Research Expedition. It was found that average surface mass balance by the stake method was +2.5g(cm)^ from 25 January 1995 to 30 January 1996 (370 days), of which about 95% of the positive balance was obtained from February to the middle of October (eight and half months). Sublimation from atmosphere to snow surface (mass input : +0.55g(cm)^) was predominant in winter (March to October) and sublimation from snow surface to atmosphere (mass output : -0.39g(cm)^) was predominant in summer (November to February). In the annual balance, sublimation from atmosphere to snow surface (+0.16g(cm)^) prevailed. This corresponds to about 6% of the annual surface mass balance. The snow temperature at 10m depth varied from -57.0 to -57.8℃, and the annual mean 10m snow temperature was -57.3℃.

This paper focuses on instrumentation and observational results of eight Automatic Weather Station (AWS) units in East Queen Maud Land, Antarctica 1995. The AWS units were installed at six sites on the ice sheet from coast to inland : the site nearest to the coast (H21) was located at 60km at 1076m altitude and a site farthest from the coast (Dome Fuji Station) was located about 920km inland at 3810m altitude. Two types of AWS units (CMOS and ARGOS) were employed. Air temperatures at H21 and Dome Fuji Station change from +2.3 to -44.4℃ and -23.3 to -80.1℃, respectively. Monthly mean July temperatures in eight AWS data are systematically higher than June and August temperatures, respectively. During the period of temperature increase in July, atmospheric pressure also increased. Wind speed during the whole period could only be obtained at MD180 at which glazed surface was observed. Prevailing wind (south-east : SE) at Relay Point covers 40% of the total wind direction, and wind from the east north-east slightly prevails (11%) at Dome Fuji Station. Atmospheric pressure at Relay Point drops in May and September, and increases in July and December. Monthly mean lapse rates on snow surface were calculated using AWS data. Annaul mean lapse rates obtained by the AWS data were systematically lower than that obtained by 10m snow temperatures in Mizuho Plateau. Increase of temperature difference between air and snow surface with altitude will be a reason for the phenomenon.

A 112.59m-deep ice core was drilled at Dome Fuji Station by a JARE-34 party in 1993 when a pilot hole was prepared for a deep core drilling operation. A preliminary examination was made for ice core chronology by two signals : one electric conductivity peaks measured in the home laboratory and the other field observation results obtained by JARE-36 party on the deeper part of the core. The electric conductivity peak analyses suggest the same 5 volcanic eruptions, in 1464 AD, 1259 AD, 865 AD, 639 AD and 346 BC, reported for the ice core of Byrd Camp, Antarctica. Field observations for ECM and crystal size distributions suggest that the period 374m depth level corresponds to the end of Wisconsin ice period. The results suggest that accumulation rate at Dome Fuji Station is between 2.5 and 3.0cm of water equivalent/year, and the end of Wisconsin-Holocene Transition will be found between depths of 340 and 400m. The depth-age curves for the core at Dome Fuji Station are obtained from the surface (at present) to 400m (at 12000years BP).

Observations of a bare ice field was carried out at Seal Rock in the S∅r Rondane area, East Antarctica. A large sublimation rate, 200 to 280mm/a, was observed on the bare ice field. Air temperature on the bare ice was about 1℃ higher than that on snow surface. The large sublimation rate was explained from the low albedo of bare ice; its value was roughly estimated from heat budget considerations. The bare ice fields were classified into 4 types according to origin.

The first wintering party at Dome Fuji Station (77°9′01″S, 39°42′12″E, 3810m a. s. l.) by the 36th Japanese Antarctic Research Expedition (JARE-36), consisting of 9 personnel, started wintering at Dome Fuji Station on January 29,1995 and continuously maintained the station until January 22,1996. The party was succeeded by JARE-37 on January 23,1996. The main scientific programs of the party were deep ice drilling, meteorological observations and glaciological observations at the station. We continuously recorded surface observations consisting of air temperature, wind velocity, wind direction, solar radiation and other visual observations from February 11,1995 to January 15,1996 when JARE-37 took over. The details will be reported by YOSHIMI et al. in this volume. The glaciological studies included surface snow sampling, condensation/sublimation measurement, air sampling, aerosol sampling, pit work, snow temperature measurement and net accumulation by the stake method through one year. The details will be reported by KAMEDA et al. in this volume. After construction of the drill site and some drill testing we started deep drilling on August 28,1995 using a 115m deep pilot hole drilled by JARE-34. We always struggled against many problems in drilling arising from extreme low temperature and the liquid-confined drilling technique which had never been used before. We were able to continue the drilling and recovered excellent quality cores even in the brittle zone between 200m and 800m below the surface. Recovered cores were processed and electrical conductivity and stratigraphy of the cores were analyzed in a science trench next to the drill site. The drilling depth exceeded 600m when the drilling was taken over by JARE-37. The details of this wintering will be reported in Nankyoku Shiryo (Antarctic Record) or elsewhere.

Upper air observations using an omega sonde system (RS80-15P : VAISALA) were carried out at Dome Fuji Station from November 7,1995 to January 3,1996. The total number of launched omega sondes was 22. Wind data could not be obtained, because VLF radio waves from omega stations could not be received at Dome Fuji Station. Seven omega sondes reached the tropopause, but the others failed due to problems with the sondes or the receiving apparatus. The average maximum height the sonde reached was about 8km above sea level. A remarkable inversion layer was found with 21 observations. The maximum temperature difference between the top and bottom of the layer was 17.8℃. The mean thickness (ΔH) of the inversion layer was 256m and the mean temperature difference (ΔT) between the top and bottom of the layer was 6.8℃. The observations show that ΔT is largest between 03 LT and 09 LT, and ΔH is thinnest between 21 LT and 03 LT.

The 36th Japanese Antarctic Research Expedition (JARE-36) commenced surface synoptic observations at Dome Fuji Station, East Antarctica on 11 February 1995 as a part of the Deep Ice Coring Project at Dome Fuji, East Antarctica (the fourth year). The first overwintering team at the Dome Fuji Station conducted year-round surface synoptic observations under extremely cold weather conditions which had not been experienced by any other Japanese project before. Synoptic observation data of surface pressure, temperature, wind direction, wind speed and flux of global solar radiation were automatically recorded every one minute. These automated observation data were obtained without trouble throughout the overwintering period. This was made possible by development of special instruments protected against frost and snow accretion, which had been the major difficulty in automated observation in the antarctic area. Visibility, total cloud amount, cloud forms, atmospheric phenomena and present weather conditions were visually observed everyday at 09,15 and 21 o'clock in local time. We obtained these visual observations year-round at Dome Fuji Station for the first time. During our one-year stay at the Station, from March 1995 to February 1996,an annual mean temperature of -53.9℃ was observed. The lowest temperature of -79.6℃ for this period was marked on 18 August 1995. Annual mean surface pressure was 598.2hPa and annual mean wind speed was 5.8m/s. Except in summer, a rather strong wind speed of about 6m/s was steadily observed throughout the year and the gust ratio was very small. That was a distinctive characteristic of the wind at the Dome Fuji Station. No prevailing wind direction was observed at the Station. The most frequent surface wind direction of each month corresponded well with the monthly averaged geostrophic wind direction at 500hPa height. Annual mean total cloud cover was about 40%. High cloud was dominant even in the case of cloudy weather. Ice prisms (diamond dust) were observed almost every day. Details of the observed data were published in the Antarctic Meteorological Data of the Japan Meteorological Agency in 1995. Details of the surface synoptic observations including accuracy of the measuring instruments at the Dome Fuji Station will be summarized in the Antarctic Report to be published by the National Institute of Polar Research.

An automatic ice fabric analyzer using an image processing method has been developed which determines the c-axis orientations of individual grains in a thin polycrystalline ice section. The computer-controlled device makes it possible to label each crystal and determine its c-axis orientation quickly without any manual operation. In our earlier studies, it was found that this method often gives a miscalculated c-axis orientation whose azimuth angle differs 90 degrees from the true one and also gives no solution in some cases. In order to improve the analysis accuracy, the method based on Light Analysis with Inclined CCD-cameras (LAIC) is improved and an automated analysis instrument has been developed. According to LAIC, while the crossed polarioids are being rotated, an ice thin section placed between crossed polarioids is photographed with three cameras, of which one is set in a vertical position, the other two are inclined 15 degree with respect to the vertical axis, The orientations of the optic axes of every individual ice crystal are calculated on a personal computer with the relation of the extinction position angles about three cameras which are calculated from the shift of the image's gray tone. A new method of Lightness Analysis has been attempted to improve the analysis accuracy. Two similar procedures are involved; however, between the two procedures, the thin sections need to be rotated 90 degree around a vertical axis, to obtain three extinction position angles. By comparing values of the two extinction position angles about the inclined cameras in both procedures, the azimuth angle can be determined accurately. It was shown that the orienting results of quartz and ice thin sections with the new method are in comparative agreement with those obtained by using a Rigsby stage, and the reproducibility of the new method is better. Over 80 percent of orienting results of thin ice sections show that the variation between the automated analysis result and that obtained by using a Rigsby stage is not over ±10 degree.