Shuji Fujita

My research fields include glaciology, physics/chemistry of ice, and climate research based on ice cores. Focusing on a better understanding of the physical/chemical properties of ice crystals, I aim to better understand the glaciological phenomena linking microscopic-scale properties and continental ice sheet scale behaviors. I have performed both laboratory experimental studies and field studies, particularly in East Antarctica. Because of their massive size, polar ice sheets have a large impact. In order to better understand the macroscopic behaviors, knowledge of ice crystals is of fundamental importance.

From 1987 to 2001, I promoted studies on the physical properties of ice crystals at the Department of Applied Physics of Hokkaido University, Sapporo. During this period, I studied (i) the clarification of the dielectric anisotropy of ice under microwave frequencies, (ii) relative complex dielectric permittivities of ice under microwave frequencies, (iii) development and application of methods/apparatus for ice core analysis, (iv) the internal structure of the Antarctic ice sheet based on radio echo sounding, and (v) the development of a continuous measurement system of the dielectric permittivity tensor of ice (and ice cores) at microwave/millimeter wave frequencies. I joined overwintering Antarctic expeditions twice during this period, once to perform glaciological research and once to perform deep ice coring at Dome Fuji Station, East Antarctica. During the 1995-1997 overwintering, I was in charge of ice core processing at Dome Fuji.

After 2002, I promoted hardware/software preparations for the next deep ice coring at Dome Fuji, at the National Institute of Polar Research, Tokyo. My colleagues and I have applied systems developed for real ice core processing. At the same time, I have organized preparations of radar sounding instruments for the observation of ice sheets. The radars were characterized by multiple frequencies (60 MHz, 179 MHz, and a few other frequencies), multiple polarization planes, and used both the amplitude and phase of the radio waves. As products of these ice sounding radars, my colleagues and I produced ice thickness data from the inland regions of East Antarctica, for which earlier data were sparse. The data were provided and used for the international compilation of a bed topography map of Antarctica, known as BEDMAP and BEDMAP2. In addition, I have worked to organize collaborations for deep ice core studies using the Dome Fuji Station ice core. In particular, I have acted as one of chairs of dating research and research of physical properties.

In 2007 and 2008, I headed a ground-based expedition team to investigate the inland of Antarctica. This expedition, the Japanese-Swedish Antarctic Expedition (JASE), was a collaboration with Swedish (and other European) scientists to better understand the glaciological environment of the Dronning Maud Land, East Antarctica. Since the field campaign ended in February 2008, we have promoted data analyses and sample analyses. These analyses are ongoing. A number of scientific papers have been presented based on the expedition.

Recently, I have focused on studying links between ice core signals and physical/chemical processes occurring in shallow and surface depths of ice sheets. In particular, I have studied firn, the intermediate state between snow and ice, in terms of deposition, metamorphism, and deformation. These studies have attempted to clarify transfer processes of climate signals into ice core signals in order to provide a clearer understanding for the ice core signals. In addition, these studies will contribute to better understanding of remote sensing data for polar regions.

Analyses of Dome Fuji ice cores (2503-m deep DF1 core and 3035-m deep DF2 core) are very big tasks; my colleagues and I have made huge efforts for manegement of these DF ice cores. These DF cores are really marvelous samples; we can uncover history of climate change over ~700 kyrs or more from these ice samples. The efforts - analyses, publications of papers and data production/publications - are ongoing, introducing innovation of ice core analysis technologies, and based on both domestic and international collaborations. Since 2016, I act as a chair of the Dome Fuji Ice Core Consortium.


I list here related web pages. Some of them are written only in Japanese. (Use the translation function of your web browser.)

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Dome Fuji Ice Core Consortium, organized by National Institute of Polar Research
http://polaris.nipr.ac.jp/~icc/NC/htdocs/

Ice Core Research Center / National Institute of Polar Research
http://polaris.nipr.ac.jp/~icrc/NC/htdocs/?lang=english

Low temperature laboratory and storage / National Institute of Polar Research
http://polaris.nipr.ac.jp/~coldlab/NC2/htdocs/

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