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In the seventh five-year plan of the Japanese Antarctic Research Expedition, Japanese scientists (led by the National Institute of Polar Research) together with a group of Swedish scientists conducted an intensive field campaign across Dronning Maud Land, East Antarctica, during the 2007/2008 austral summer season. This paper details the entire scope of the field activities of the project, and includes an outline of the field expedition, manning and roles, logistics, communications, navigation, and observations. This report should provide valuable information for future programs in Antarctica.

In the seventh five-year plan of the Japanese Antarctic Research Expedition, a group of Japanese scientists (led by the National Institute of Polar Research) together with a group of Swedish scientists, conducted field surveys to better understand the glaciology of the ice sheet in Dronning Maud Land, East Antarctica, during the 2007/2008 austral summer season. This paper reports on the planning and field preparations, and outlines the scientific achievements of the field expedition. We have gained numerous new scientific insights on the spatio-temporal distribution of the ice sheet environment in the inland plateau. Here, we provide an overview of the new knowledge gained.

Antarctica is a continent characterized by the huge ice mass above the bedrock. Better understanding the internal physical mechanism for existence and changes is essential to study how ice is fixed on the continent in water cycles in the atmosphere-ocean-ice system on the earth. The National Institute of Polar Research, Tokyo, has a long history of using ice sounding radar to study the ice sheet. This paper gives a brief history of the development, specifications, observations and major results. In particular, it explains the use of multiple frequencies and polarization planes. This paper also comments on the recent use of phase information in addition to power information. I hope that this document will be useful for future use of the radar.

This paper describes observational results of surface mass balance (SMB) at Dome Fuji (77°19'01″S, 39°42'11″E; 3810m a.s.l.), East Antarctica from 1995 to 2006. The SMB was estimated using 36 bamboo stakes (grid of 6×6, placed at 20m intervals). The heights of the stake tops from the snow surface were measured at 0.5cm resolution twice monthly in 1995, 1996, 1997, and 2003, and once a year for the rest of the study period. The annual SMB from 1995 to 2006 at Dome Fuji was 27.3±1.5kgm^a^. This result agrees well with the annual SMB from AD 1260 to 1993 (26.4kgm^a^), estimated from volcanic signals in the Dome Fuji ice core. From 1995 to 2006, there were 37 incidences of negative or zero annual SMB, which was 8.6%. Compared with similar studies at Vostok, South Pole and Dome C, we found that a site with SMB over 190kgm^a^ is expected to have annual snow accumulation at the 95% confidence level. Sites from 1500 to 2500m above sea level fit the criteria on the Antarctic ice sheet. According to stake and snow pit observations at Vostok, we estimated that the probability of an annual layer missing (hiatus) at Dome Fuji under present-day and glacial conditions are 9.4% and 11.4%, respectively. Variations of SMB measured by 36-stakes for 12 years were also analyzed.

Deep ice coring was carried out at Dome Fuji Station, Antarctica in 1995 and 1996 following a pilot borehole drilled and cased with FRP pipes in 1993,and reached 2503.52m in December 1996. Total numbers of ice coring runs below the pilot borehole and chip collection were 1369 and 837 respectively. The mean coring depths per run and per day were 1.75m and 8.21m respectively. We report the outline of the coring operation, the system, coring method, and troubles encountered during the coring work.

In the area west of Mizuho Plateau, outflow of the ice sheet is hindered by a chain of mountains (Sor Rondane, Belgica and Yamato Mountains etc.) lying along the coast of the continent and ice shelves are developing at the margin of the ice sheet. Therefore the ice sheet geomorphology and dynamical behavior in this area are quite different from those on the Mizuho Plateau. In order to describe the response of the East Antarctic ice sheet to climatic change, we need to know the influence of the presence of mountains on stability of the ice sheet. This glaciological study aims to investigate whether the ice sheet and the ice shelf in this area are now increasing or decreasing in size possibly, in response to atmospheric warming, how far this part of the ice sheet departs from a steady state, and how the influence of climatic change is left inside the ice sheet and the ice shelf. For this purpose the following studies were performed in 1988 and 1989. 1) A series of shallow drillings along a selected flow line upstream of the Sor Rondane Mountains to Breid Bay. 2) Surface flow velocity, strain and mass balance measurements on the flow line. 3) Monitoring of a valley glacier in the Sor Rondane Mountains.

Recent observations show that the ice sheet in the Shirase Glacier drainage basin, East Antarctica, is thinning. If the observed thinning is assumed to be a transitional process in which the ice sheet is adjusting to the present climate, an equilibrium ice sheet profile which adjusts to the present climate would provide us with information for understanding the present behavior of the ice sheet. The equilibrium ice sheet profile was estimated by using a three-dimensional non-steady state ice sheet model. Estimations were carried out with data based on observations of bedrock topography, surface elevation, accumulation rate and surface temperatures, and their extrapolation for areas where there is no field data. And the equilibrium ice sheet profile against various parameters, e.g. surface temperatures, accumulation rate and geothermal heat flux, was investigated. Results of the calculation showed that an almost stationary state of the ice sheet was achieved after (10)^4 model years when started from the present profile of the ice sheet. The equilibrium ice sheet profile depended on bedrock topography and tested parameters sensitively, but the calculations indicated that ice-thickness tend to decrease in the middle-stream region in general. It was also revealed that the ice sheet in the vicinity of the Yamato Mountains was relatively stable even if the parameters were changed.

Dirt bands were observed on the surface of the bare ice fields around the SΦr Rondane Mountains during the search for Antarctic meteorites in 1988-1989. Dirt bands were commonly distributed on the bare ice around the mountains, especially in Nansenisen. Dirt bands were collected and filtered after melting. Microscopic observation revealed that dust materials were composed mainly of volcanic glass shards. Five types of volcanic ash were preliminarily clarified with respect to the colors (black, dark gray, gray, reddish brown and pale gray) and sizes (5-50μm) of the particles. The EPMA chemical analyses indicated that the volcanic glass shards contained 50-70% SiO_2 and belonged to the nonalkaline region considering from the SiO_2-(Na_2O+K_2O) diagram.

A systematic search for Antarctic meteorites was carried out by the Asuka winter party of the 29th Japanese Antarctic Research Expedition on the bare ice field around the Sφr Rondane Mountains in the 1987-1988 and 1988-1989 field seasons. More than 2000 meteorite specimens as individuals or fragments were collected from three main areas around the mountains. Their total weight could be more than 400kg. The collection of these meteorites, which will be named officially Asuka-87 and Asuka-88 meteorites, consist of various types of meteorites, such as irons, stony-irons, chondrites, achondrites and carbonaceous chondrites, including some unique specimens. The largest specimen in this collection is a 46kg LL type ordinary chondrite.

An optical scanner for stratigraphical study was developed for the Dome Fuji ice core project II. The optical scanner measures two-dimensional light scattering intensities and records optical structures of ice cores. We developed the scanner hardware and control software. The line scanner is controlled by a personal computer and is constructed for automatic measurement. The sliding speed of the scanner is about 5mm per second and, therefore, one ice core sample with a standard length for our sample processes (1.5m long) can be measured within about six minutes. The line scanner was transported to Dome Fuji Station, Antarctica, by the wintering party of the 44th Japanese Antarctic Research Expedition (JARE-44), and will be used for Dome Fuji II ice core measurement by the JARE-45 summer party and successive parties.

The ten-man summer field party of the 29th Japanese Antarctic Research Expedition (JARE-29) carried out geological, geomorphological and geodetic field work and a meteorite search in the Sør Rondane Mountains, mainly east of Byrdbreen (71°40'-72°15'S, 26°30'-28°E) from January 6 to February 3,1988 (29 days). In addition, on December 21 and 22,1987,two surveyors from our party took aerophotographs in the eastern and central parts of the mountains, using a "Pilatus Porter" plane. Being favored by good weather and no serious accident, we were able to complete most of the work that we had planned. This paper is a description of the field operation including logistics and a brief report on the geological, geomorphological and geodetic field work, meteorite search and aerophotography.

In the seventh five-year plan of the Japanese Antarctic Research Expedition, a group of Japanese scientists (led by the National Institute of Polar Research) together with a group of Swedish scientists, conducted field surveys to better understand the glaciology of the ice sheet in Dronning Maud Land, East Antarctica, during the 2007/2008 austral summer season. This paper reports on the planning and field preparations, and outlines the scientific achievements of the field expedition. We have gained numerous new scientific insights on the spatio-temporal distribution of the ice sheet environment in the inland plateau. Here, we provide an overview of the new knowledge gained. [ABSTRACT FROM AUTHOR]