ILTS International Symposium"Frontier of Low Temperature Science"Book of Abstracts

November 9-10, 2009
Auditorium,
Institute of Low Temperature Science,
Hokkaido University

ILTS International Symposium "Frontier of Low Temperature Science"
November 9-10, 2009
Auditorium, Institute of Low Temperature Science, Hokkaido University(See http://www.lowtem.hokudai.ac.jp/english/eaccess.html.)

Program<Monday, 9 November 2009>
Plenary Session, 10:00-11:20

Chair: Naoto Ebuchi

10:00-10:10

Welcome Address
Prof. Takeo Hondo, Vice President of Hokkaido University

10:10-10:40

Keynote SpeechProf. Akira Kouchi, Director of ILTS, Hokkaido University
Towards a new era in low temperature science

10:40-11:20

Keynote SpeechProf. Frank Wilhelms (Alfred Wegener Institute)
How can ice science satisfy the public attention in a warmer world?

Lunch Break, 11:20-13:30

Session 1. Environmental Biology, 13:30-16:30

Chair: Ayumi Tanaka

1-1

13:30-14:10
Rudolf Amann, Bernhard Fuchs, Paola Gomez, Martha Schattenhofer, Marga Schüler(Max Planck Institute for Marine Microbiology)
Analyzing the microbial catalysis of biogeochemical cycles by combining quantitative
single cell studies with environmental genomics

1-2

14:10-14:35
Swingley, W. D., Takizawa, K., Iwai, M., Kato, N., and Minagawa, J. (ILTS, Hokkaido
University)
Photoacclimation of a marine picophytoplankton Ostreococcus tauri

1-3

14:35-15:00
Satoshi D. Ohdachi (ILTS, Hokkaido University)
Biogeographic characteristics of terrestrial mammals in Hokkaido

1-4

15:00-15:25
Hisaya Kojima (ILTS, Hokkaido University)
Deposited snow as a habitat of bacteria: a case of snow coloration associated with ironaccumulation

1-5

15:25-16:05
Hiroyo Otaki, R. Craig. Everroad (Tokyo Metropolitan University), Satoshi Hanada (Tokyo
Metropolitan University/Institute for Biological Resources and Functions), Shin Haruta, andKatsumi Matsuura (Tokyo Metropolitan University)
Electron cycling in ecosystems: An analysis in microbial community

1-6

16:05-16:30
Toshihiko Hara, Kiyomi Ono, Norifumi Ukaji, Akihiro Sumida, Ryouichi Tanaka, Ayumi
Tanaka (ILTS, Hokkaido University), Aya Iwasaki, Ken’ichi Ogawa (Research Institute for
Biological Sciences), Kazuko Uchiyama, Kazuhito Kita, Ichirou Watanabe, Michiyasu
Yasaka (Hokkaido Forestry Research Institute)
Molecular and ecological studies on boreal forests in the cryosphere

Session 2. Poster Session (with coffee and tea), 16:30-18:00

Chair: Ayumi Tanaka

2-1

Hisashi Ito and Ayumi Tanaka (ILTS, Hokkaido University)
Photosystem development of marine cyanobacterium Prochlorococcus

2-2

Yasuhito Sakuraba, Ryouichi Tanaka, and Ayumi Tanaka (ILTS, Hokkaido University)
Delayed leaf senescence by enhanced chlorophyll b biosynthesis

2-3

Edgard A. Bontempo e Silva, Toshihiko Hara, Akihiro Sumida, Kyomi Ono, Yuji Kodama,
Taro Nakai (ILTS, Hokkaido University), and Shigeru Uemura (Field Science Center for
Northern Biosphere, Hokkaido University)
Ecophysiological responses of Abies sachalinensis seedlings to two contrasting
environments in a sub-boreal forest of Hokkaido, Japan

2-4

Azusa Tabata, Kiyomi Ono, Akihiro Sumida, and Toshihiko Hara (ILTS, Hokkaido
University)
Effects of soil water conditions on the morphology, phenology and photosynthesis of Betula
ermanii in the boreal forest

2-5

Masanori Ochiai (ILTS, Hokkaido University), Kiyohiro Takahasi, and Fuyuhiko Inagaki(Graduate School of Pharmaceutical Sciences, Hokkaido University)
Insect immunity: Solution structure of the silkworm ßGRP N-terminal domain reveals themechanism for ß-1,3-glucan-specific recognition

2-6

Ryutaro Tokutsu and Jun Minagawa (ILTS, Hokkaido University)
Molecular characterization of photosynthetic protein complexes of marine diatoms

2-7

Masazumi Tsutsumi, Hisaya Kojima (ILTS, Hokkaido University), Tomoya Iwata(Department of Ecosocial System Engineering, University of Yamanashi), and Manabu
Fukui (ILTS, Hokkaido University)
Community structure of methane-oxidizing bacteria in water column of a freshwater lake

2-8

Kato, Y., M. Iwasaki, M. Ochiai, K. Shimada, and C. Katagiri (ILTS, Hokkaido University)
Weta Lipophorin – Comparison with other insects –2-9

Shigeru Aoki (ILTS, Hokkaido University), Mikio Naganobu (Fisheries Research Agency),
Takashi Ishimaru (Tokyo University of Marine Science and Technology), Stephan R.
Rintoul (CSIRO), Nathaniel L. Bindoff (University of Tasmania), and Keiichiro Ohshima(ILTS, Hokkaido University)
Stable oxygen isotope ratio of sea water and its spatial distribution at the continental marginof Antarctica

2-10

Takenobu Toyota (ILTS, Hokkaido University), Christian Haas (University of Alberta), andTakeshi Tamura (ILTS, Hokkaido University)
Size distribution of sea ice floes in the Antarctic marginal ice zones in late winter

2-11

Yamamoto, S. and Kawamura, K. (ILTS, Hokkaido University)
Stable hydrogen isotopic compositions of n-alkanes in atmospheric aerosols from Tokyo as
a potential tracer to decipher the source region tracer of terrestrial plant waxes

2-12

Chusei Fujiwara, Kazuya Yamashita (Graduate School of Environmental Science, Hokkaido
University), Yasushi Fujiyoshi (ILTS, Hokkaido University)
Detection of organized airflow structure in the atmospheric boundary layer using a
3D-scannnig Doppler lidar

2-13

Takuya Nakanowatari and Kay I. Ohshima (ILTS, Hokkaido University)
Changes in the Sea of Okhotsk due to global warming – Weakening pump function to theNorth Pacific –2-14 Yasushi Fukamachi, Kay I. Ohshima, Shigeru Aoki, Daisuke Simizu, Takeshi Tamura (ILTS,
Hokkaido University), Yujiro Kitade, Daisuke Hirano (Faculty of Marine Science, Tokyo
University of Marine Science and Technology), Shuki Ushio, and Gen Hashida (National
Institute of Polar Research)
Direct observations of newly-found Antarctic Bottom Water and the associated sea-ice
production - Cape Darnley Project 2-15

Takeshi Tamura, Kay I. Ohshima, and Sohey Nihashi
Mapping of sea ice production in the Southern Ocean

2-16

Tomoyasu Kuno, Yuji Kodama, and Taro Nakai (ILTS, Hokkaido University)
Evaluation of snowfall interception of boreal forest

2-17

Sasakawa, M. (Center for Global Environmental Research, NIES), K. Shimoyama (ILTS,
Hokkaido University), T. Machida (Center for Global Environmental Research, NIES), N.
Tsuda (Global Environmental Forum), H. Suto (Japan Aerospace Exploration Agency), M.
Arshinov, D. Davidov, A. Fofonov, O. Krasnov (Institute of Atmospheric Optics of SB
RAS), T. Saeki, Y. Koyama, and S. Maksyutov (Center for Global Environmental Research,
NIES)
Continuous measurement of carbon dioxide and methane concentration using 9-tower
network over Siberia

2-18

Shoko Abe (Graduate School of Environmental Science /ILTS, Hokkaido University) andTomohiro Nakamura (ILTS, Hokkaido University)
Energy transfer in a breaking internal wave

2-19

Hirotaka Sasaki (Graduate School of Environmental Science, Hokkaido University), Sumito
Matoba (ILTS, Hokkaido University), and Takayuki Shiraiwa (Research Institute for
Humanity and Nature)
Iron flux to the northern North Pacific estimated from the ice core of Mt. Wrangell, Alaska

2-20

Yoshinori Furukawa (ILTS, Hokkaido University), Etsuro Yokoyama (Gakushuin
University), Izumi Yoshizaki, Shinichi Yoda, Tetsuo Tanaka (JAXA), Taro Shimaoka (JSF),
Takehiko Sone (JAMSS), and Toshiyuki Tomobe (IHI Aerospace)
Pattern formation during ice crystal growth in pure D2O water –ISS-KIBO Experiments–

2-21

Gen Sazaki (ILTS, Hokkaido University/JST-PRESTO), Salvador Zepeda, Shunichi
Nakatsubo (ILTS, Hokkaido University), Etsuro Yokoyama (Gakushuin University), andYoshinori Furukawa (ILTS, Hokkaido University)
Direct visualization of elementary steps and quasi-liquid layers at air-ice interfaces byadvanced optical microscopy

2-22

Salvador Zepeda, Hiroyuki Nakaya (ILTS, Hokkaido University), Etsuro Yokoyama(Gakushuin University), and Yoshinori Furukawa (ILTS, Hokkaido University)
Antifreeze protein kinetics at the ice/solution interface

2-23

Hakime Seddik, Ralf Greve (ILTS, Hokkaido University), Thomas Zwinger (CSC–IT
Center for Science Ltd.), and Olivier Gagliardini (Laboratory of Glaciology andEnvironmental Geophysics, CNRS)Steady-state simulations of the Greenland ice sheet using a three-dimensional full-Stokes
model

2-24

Thorben Dunse (Department of Geosciences, University of Oslo/ILTS, Hokkaido
University), Thomas V. Schuler, Jon Ove Hagen (Department of Geosciences, University ofOslo), Ralf Greve (ILTS, Hokkaido University), Geir Moholdt, and Trond Eiken(Department of Geosciences, University of Oslo)
Modelling flow dynamics and geometry of the Austfonna ice cap, Svalbard

2-25

Shun Tsutaki, Daisuke Nishimura, Takeshi Yoshizawa (Graduate School of Environmental
Science, Hokkaido University), and Shin Sugiyama (ILTS, Hokkaido University)
Impact of proglacial lake formation on the retreat of Rhonegletscher, Switzerland

2-26

Iizuka Yoshinori Iizuka, Akira Tsuchimoto, Toshimitsu Sakurai (ILTS, Hokkaido
University), Motohiro Hirabayashi (National Institute of Polar Research), Toshitaka Suzuki(Faculty of Science, Yamagata University), Takayuki Miyake (National Institute of Polar
Research), Ryu Uemura (LSCE, CEA-CNRS), Shuji Fujita, Hideaki Motoyama, Yoshiyuki
Fujii (National Institute of Polar Research), and Takeo Hondoh (ILTS, Hokkaido
University)
Constituent elements of soluble particles of the Dome Fuji surface snow and ice core

2-27

Hidaka, H., M. Watanabe, A. Kouchi, N. Watanabe (ILTS, Hokkaido University)
Formation of deuterated formaldehyde and methanol by quantum tunneling H-D
substitution and H(D) addition reactions on low temperature surfaces

2-28

Manabu Fukui, Shin Sugiyama, Shigeru Aoki (ILTS, Hokkaido University), Masanobu
Yamamoto (Faculty of Environmental Earth Science, Hokkaido University), Takenobu
Toyota (ILTS, Hokkaido University), Takanobu Sawagaki, Genta Mizuta (Faculty ofEnvironmental Earth Science, Hokkaido University), Keiichiro Ohshima, Yasushi
Fukamachi, Sumito Matoba, Kou Shimoyama, Yoshinori Iizuka, and Tomoko Endo (ILTS,
Hokkaido University)
Antarctic Science Curriculum of Hokkaido University – Contribution to the International
Antarctic Institute –2-29

Kunio Shinbori, Toru Takatsuka, Shunichi Nakatsubo, Takeshi Chigai, Kazuya Ono, Yukako
Kato, Kenta Chubachi, Kazuyuki Fujita, Masao Ishikawa, Hiroki Fukushi, Masayuki Ikeda,
and Naoto Ebuchi (ILTS, Hokkaido University)
Technical supports in ILTS

Reception, 18:00-19:30(Room 215)

<Tuesday, 10 November 2009>
Session 3. Water and Material Cycles, 9:30-12:00

Chair: Yasushi Fujiyoshi

3-1

9:30-10:00
Ding Yihui, Wang Zunya, and Song Yafang (National Climate Center, China Meteorological
Administration)
Cause of the unprecedented freezing disaster in January 2008 and its possible association
with the global warming

3-2

10:00-10:30
Toshio Koike (The University of Tokyo)
Data integration and analysis system for water cycle

3-3

10:30-11:00
Yasunobu Iwasaka (Kanazawa University)
Kosa (Asian dust) particles and atmospheric constituents on particle surface

3-4

11:00-11:30
Naohiro Yoshida (Tokyo Institute of Technology)
Isotopomer studies to trace water and material cycles featuring some extreme environments

3-5

11:30-12:00
Yasushi Fujiyoshi (ILTS, Hokkaido University)
Why cloud science?

Lunch Break, 12:00-13:00

Session 4. Pan-Okhotsk Researches, 13:00-15:30

Chair: Jun Nishioka

4-1

13:00-13:50
Bo Qiu (School of Ocean & Earth Science & Technology, University of Hawaii at Manoa)
Decadal variability in the North Pacific Subpolar Gyre circulations

4-2

13:50-14:20
Sumito Matoba (ILTS, Hokkaido University)
50-year records of climate changes in ice-cores from Kamchatka and Alaska

4-3

14:20-14:50
Osamu Seki (ILTS, Hokkaido University)
Large changes in seasonal sea ice, sea surface temperature and productivity in the Sea of
Okhotsk during the last deglaciation

4-4

14:50-15:20
Tomohiro Nakamura (ILTS, Hokkaido University)
Modeling the Pan-Okhotsk region
15:20-15:30

Discussion

Coffee Break, 15:30-16:00

Session 5. Frontier Ice and Snow Science, 16:00-18:30

Chair: Yoshinori Furukawa

5-1

16:00-16:50
John Wettlaufer (Yale University)
Letters from the Sky: Nakaya, Sapporo and the broad scientific reach of the physics of ice

5-2

16:50-17:25
Shuji Fujita (National Institute of Polar Research), Junichi Okuyama, Akira Hori, and Takeo
Hondoh (ILTS, Hokkaido University)
Metamorphism of stratified firn at Dome Fuji, Antarctica: A mechanism for local insolation
modulation of gas transport conditions during bubble close-off

5-3

17:25-17:45
Ralf Greve (ILTS, Hokkaido University)
Dynamic/thermodynamic modeling of ice sheets in changing climates

5-4

17:45-18:05
Naoki Watanabe (ILTS, Hokkaido University)
Ice surface reactions: its role in chemical evolution in space

5-5

18:05-18:25
Gen Sazaki (ILTS, Hokkaido University)
Direct visualization of elementary steps and quasi-liquid layers at air-ice interfaces byadvanced optical microscopy

Closing Remarks
Prof. Manabu Fukui, Vice Director of ILTS, Hokkaido University

Keynote Speeches

Towards a New Era in Low Temperature Science
Akira Kouchi
Institute of Low Temperature Science, Hokkaido University
kouchi@lowtem.hokudai.ac.jp

The Institute of Low Temperature Science was founded in 1941 as the first research institute affiliated with
Hokkaido University. The institute owes its establishment to the achievements of Dr. Ukichiro Nakaya,
professor of the department of physics, who was the first in the world to create artificial snow crystals. In thehalf century, the institute had conducted unique research on various natural phenomena occurring in climatic
low temperatures.
As it became clear that the cryosphere has an important role in the global climate system and ecosystem, naturein the cryosphere had gained attention in recent years as an important subject of study regarding environmental
earth science. To promote interdisciplinary studies beyond the existing scientific framework such that they are
pursued jointly by its own and other researchers, the Institute of Low Temperature Science had reorganized in1995.
In 2008, we established a new system incorporating Joint Research Division with three large divisions (Water
and Material Cycles Division, Frontier Ice and Snow Science Division, and Environmental Biology Division)and Pan-Okhotsk Research Center in order to increase opportunities for conducting interdisciplinary cryosphereresearch with domestic and foreign researchers. Joint Research Division has various functions, such as“Program”, “Joint Research and Collaboration”, and “Technical Support” to enhance the function as thecommunity center. “Program” is accomplished in full-time faculty members’ lead with complete support ofthree research divisions and the Pan-Okhotsk Research Center. Furthermore, to promote further joint research,
we concluded an agreement between one domestic and four foreign institutions in 2008 and 2009. As a leading
research center for low temperature science, we have been promoting joint research in this way.
Academic advancement requires a broad point of view as well as intense investigation. Joint research fusing
various research fields can be said to be the sprit of our institution’s foundation. In the present symposium,
results of “Programs” ranging various fields will be presented. To evaluate almost finished “Programs” criticallyand to further activate ongoing interdisciplinary “Programs”, we anticipate active discussion and criticalcomments.

How can Ice Science Satisfy the Public Attention in a Warmer World?
Frank Wilhelms
Alfred Wegener InstituteFrank.Wilhelms@awi.de

The worldwide public is aware that humankind lives in a changing environment. Typical questions to scientists
addressed by the public are e.g.: How much will sea level rise at our shores in 100 years? How will average
seasons and the distribution of precipitation be in 30 years in our country? Will we be able to send ships over the
North Pole in a few decades?
To address these questions one has to understand the various interactions between the atmosphere, the oceans
and the ice covering both polar land and seas. The changing physical properties are tightly coupled to the
biological and geochemical cycles which have therefore to be included to forecast the fate of the earth system.
Ice is a key player in the earth system as the polar ice sheets store an equivalent of more than 60 m of sea level
difference. Sea ice has compared to open water a much higher ability to reflect radiation instead of heating byabsorption.
Both the Alfred Wegener Institute (AWI) and the Institute of Low Temperature Science (ILTS) have some of
their major research topics covering aspects of ice beginning with the basic physical properties of ice crystals
and their inclusions, formation of meteoric and sea ice, internal structure of ice sheets towards modelling andobserving the evolution of ice sheets and sea ice in the earth system. Together both institutes cover an almost
complete portfolio of research addressed to ice and lay the basis for research towards answering the questions
by the public.
Selected ice research topics relevant for the AWI and the ILTS will be presented, as e.g. microstructure of ice,internal electromagnetic reflections in ice sheets, air content in natural ice, modelling the evolution of ice sheets
and distribution of sea ice under different climatic conditions. Latest reconstructions of sea ice extent and ice
sheet geometry from proxy parameters in ice and sediment cores permit the comparison with modelling results.

Session 1. Environmental Biology

1-1

Analyzing the Microbial Catalysis of Biogeochemical Cycles by Combining
Quantitative Single Cell Studies with Environmental Genomics
Rudolf Amann, Bernhard Fuchs, Paola Gomez, Martha Schattenhofer, and Marga Schüler
Max Planck Institute for Marine Microbiology
ramann@mpi-bremen.deCentral steps of global biogeochemical cycles are catalyzed by marine microorganisms. Molecularfingerprints have long indicated novel, often high microbial diversity, but fell short of quantify specificpopulation sizes and biomasses. Fluorescence in situ hybridization (FISH) with rRNA-targeted
oligonucleotide probes yields such quantitative data on spatio-temporal distributions. By catalyzed reporter
deposition fluorescence in situ hybridization (CARD-FISH) abundant marine “key species” can even bequantified in very oligotrophic environments3. For some of them, e.g. for heterotrophic polymer-degrading
bacteria, representative pure cultures have recently become available.
We are studying coastal bacteria involved in carbon cycling like “Gramella forsetii” (Phylum Bacteroidetes)1,
and “Congregibacter litoralis” (NOR5/OM60 clade of Gammaproteobacteria)2. The genome of “G.
forsetii” shows ample adaptations to the degradation of polymeric materials, whereas “C. litoralis” turned
out to be the first gammaproteobacterial aerobic anoxygenic photoheterotroph (AAnP). The existence of thisnovel clade of AAnPs had been predicted by metagenomics. Massive sequencing efforts are now enablingcomparative genomics of additional marine Bacteroidetes, confirming their central involvement in carbon
cycling.
Metagenome projects at the MPI Bremen have so far focussed on benthic processed such as the anaerobic
oxidation of methane, and have only been started for marine planktonic settings. By the combination ofquantitative single cell studies and environmental genomics we hope to gain a more detailed understandingof specific functions of particular marine microbial populations. Our data could in the future contribute topredictive models of the role and fate of particular microbial populations at defined environmental settings.

References
Bauer, M. Et al., 2006. Environ. Microbiol. 8: 2201-2213.
2
Fuchs, B.M.et al., 2007. Proc. Natl. Acad. Sci. USA 104: 2891-2896.
3
Schattenhofer, M. et al., 2009. Environ. Microbiol. 11: 2078-2093.
1

1-2

Photoacclimation of a Marine Picophytoplankton Ostreococcus tauri
Swingley, W. D, Takizawa, K., Iwai, M., Kato, N., and Minagawa, J.
Institute of Low Temperature Science, Hokkaido University
minagawa@lowtem.hokudai.ac.jp

Paradoxically, the primary stress on photosynthetic organisms is their life-giving sun. One of the methods
land plants have developed to deal with this high-light stress is the xanthophyll cycle, but the extent of its use
is not clear in marine algae, which are responsible for nearly half of the global carbon fixation. In this work
we characterized non-photochemical quenching, including xanthophyll cycling, and photosynthetic
efficiency in a marine phytoplankton, Prasinophyceae, which is a broad class of early-branching eukaryotic
green algae. They are found ubiquitously throughout the ocean and contribute considerably to global
carbon-fixation. Ostreococcus tauri, as the first completely sequenced prasinophyte, is an ideal model species
for studying the photosynthesis and its acclimation to the environments. We found that under high-light stress,
O. tauri rapidly de-epoxidated up to 50% of its violaxanthin to antheraxanthin, but converted less than 20%
to zeaxanthin. This one-step xanthophyll cycle correlated to an extremely large capacity for
non-photochemical quenching (NPQ > 2.8); a level that is comparable to the globally successful diatoms.
When grown under a variety of light intensities, O. tauri cells drastically adjusted both their xanthophyll poolsize and photosynthetic efficiency. Such changes help O. tauri dynamically balance photoprotection withlight-harvesting.

1-3

Biogeographic Characteristics of Terrestrial Mammals in Hokkaido
in Hokkaido
Satoshi D. Ohdachi
Institute of Low Temperature Science, Hokkaido University
ohd@lowtem.hokudai.ac.jp

Hokkaido is separated from Honshu (the mainland of Japan) by Tsugaru Strait, with the narrowest point of
18 km. It is well known that bird fauna quite differs beyond this strait, which was first pointed out by Thomas.
W. Blakiston and his colleague based on his bird specimens collected by in the late 19th century. Later, it wasdemonstrated that faunae of other terrestrial vertebrates are also rather different between Honshu andHokkaido, divided by the strait. Therefore, Tsugaru Strait is often called Blakiston’s line, which is one of themost important biogeographic lines in the Japanese Archipelago. As the northern demarcation, Hokkaido isalso separated from Sakhalin (Karafuto) by Soya (La Pérouse) Strait with 40 km shortest distance. Soya
Strait was also proposed as a biogeographic line (Hatta’s Line), especially for amphibian and reptile faunae. It
however is now regarded as a less important. Further, Sakhalin and Primorski/Khabarovsk region(North-eastern Asian Continent) are separated by Mamiya (Tatar) Strait with 7 km narrowest point. The final
opening of this strait occurred 5-7,000 years ago and it does not play an important role to segregate terrestrial
vertebrate fauna Sakhalin and the continent. In terrestrial mammals, species composition of Hokkaido fauna
is a part of Sakhalin or Honshu fauna, and Hokkaido shares much more common “species” with Sakhalin
than Honshu. Thus, terrestrial mammalian fauna of Hokkaido is correlated to that of East Siberia morestrongly than Honshu. In addition to such classic “present/absent” biogeographic information, we can infer
more detailed process of biogeographic history based on molecular phylogeny and population genetics. In
the present talk, I introduce phylogeographic characteristics and uniqueness of Hokkaido for some terrestrial
mammals. You will see not only that Hokkaido fauna is strongly affected by East Siberian fauna but also that
Hokkaido has a unique position in biogeographic events for some mammal species.

1-4

Deposited Snow as a Habitat of Bacteria: a Case of Snow Coloration
Associated with Iron Accumulation
Hisaya Kojima
Institute of Low Temperature Science, Hokkaido University
kojimah@lowtem.hokudai.ac.jp

The importance of biogeochemical processes in snow and related environments has been increasingly
appreciated in recent years. Although biological activities in such cold environments tend to be suppressed toa low level, their contributions to annual nutrient budgets can be significant when they are cumulated throughthe winter to early spring. In several cases, these activities are tightly linked to physical characteristics ofsnow. In several mires in Japan, reddish-brown colored snow is observed at the time of melting snow.
Colorations of snow by microbial cells are typically caused by oxygenic phototropic organisms, referred to assnow algae. The brown snow contains abundant spherical brown particles resembling snow algae in size,
however, the color of particles is entirely distinct from that of typical snow algae. In addition, these particles
are accumulated in deeper layers of snow, e.g., 1 m under the surface, where no light would be available forphotosynthesis. In order to characterize this remarkable phenomenon, microbial community was analyzed
along with chemical analyses. A core sample of snow which had colored region was investigated to reveal
vertical shifts in physicochemical characteristics and microbial community structure. The abundance ofparticles peaked within the colored layer, and correlated with amount of microbially reducible Fe(III).
Interstitial water of colored layer was enriched with Fe(II), and characterized by reduced concentration ofdissolved methane. The bacterial community structure in the colored region was characterized by higher
relative abundance of iron-reducing bacteria (the genus Geobacter) and methane-oxidizing bacteria (thegenus Methylobacter). These bacteria seem to take ecological advantage of environmental conditions in thesnow coverage on wetlands, and iron compounds and methane are suggested to be the key substances thatcan be investigated to understand the mechanism of this phenomenon.

1-5Electron Cycling in Ecosystems: An Analysis in Microbial Community
Hiroyo Otaki 1, R. Craig. Everroad 1, Satoshi Hanada 1, 2, Shin Haruta 1, and Katsumi Matsuura 1
1
Department of Biology, Tokyo Metropolitan University
2
Institute for Biological Resources and Functions, National Institute of Advanced Industrial Science andTechnology (AIST)
matsuura-katsumi@tmu.ac.jp

Cyclings of carbon, oxygen, nitrogen, sulfur, and hydrogen in ecosystems interact each other through redox
reactions, i.e., electron flow between the cycles. Although the electron flow is closely related to the energy
flow in ecosystems, the concept of electron flow in energy flow is not so important in aerobic world because
the carbon cycle is in parallel with the electron cycle. Electrons move from water to CO2 and return fromorganic compounds to oxygen. However, in the whole biosphere, which includes both aerobic and anaerobic
environments, the concept of electron flow between the nutrient cycles becomes important for the energyflow.
We have been studying hydrogen production and consumption in hot spring microbial mats. In the course of
study, we have realized that electrons are cycling in the community through various nutrients. In the cycle,
electrons are pumped by solar energy in anoxygenic photosynthetic bacteria.
Microbial mats were collected at Nakabusa hot spring and their hydrogen production was measured in
artificial hot-spring water at 65°C. In the presence of an inhibitor of sulfate reduction, molybdate, significant
production of hydrogen gas was detected. This hydrogen production largely decreased under illumination.
The fermentative bacterium, Fervidobacterium sp., seem to produce hydrogen in the mats, and that thishydrogen is consumed by the sulfate-reducing bacteria, Thermodesulfobacterium sp. The anoxygenic
photosynthetic bacterium, Chloroflexus aggregans, affected hydrogen production under illumination, andconsidered to provide organic compounds to the fermenter. By disrupting the mat structure and cell-cellinteractions, hydrogen production was observed despite the lack of inhibitor, demonstrating this structural
disruption interfered with hydrogen consumption.
The production and consumption of hydrogen in the microbial mat seem to connect both to the carbon cycle
and sulfur cycle in the community. Moreover, hydrogen production and consumption in the mat is thought tobe part of the electron cycling in the mat. The microbial mat community may then be a model for the
combination of nutrient and electron cycling in various ecosystems, which include anaerobic environments,on the earth.

1-6

Molecular and Ecological Studies on Boreal Forests in the
Cryosphere
Toshihiko Hara 1, Kiyomi Ono 1, Norifumi Ukaji 1, Akihiro Sumida 1, Ryouichi Tanaka 1, Ayumi Tanaka 1, Aya
Iwasaki 2, Ken’ichi Ogawa 2, Kazuko Uchiyama 3, Kazuhito Kita 3, Ichirou Watanabe 3, Michiyasu Yasaka 3
1
The Institute of Low Temperature Science, Hokkaido University
2
Research Institute for Biological Sciences, Okayama
3
Hokkaido Forestry Research Institute, Bibai
t-hara@pop.lowtem.hokudai.ac.jp

The boreal forest (N 45 – 70 degrees) occupies about 1/3 of the total world forest area. It is assumed that theboreal forest is most sensitive to global climate change such as global warming. Our research groups are
conducting molecular, physiological, biochemical and ecological studies on boreal forests. The characteristicsof the cryosphere, where the boreal forest occurs, are low precipitation and low temperature. We assume thatphotooxidative stress occurs strongly under such environmental conditions. We have found that (1)photooxidative stress in the spring triggers flowering in boreal forest trees; (2) the gap regeneration that
occurs in tropical or temperate forests does not occur in boreal forests, that is, seedlings can survive under the
canopy of adult trees (in low light) but not in gaps (in high light) in boreal forests; (3) evergreen conifers haveseveral protective mechanisms against photooxidative stress in the autumn and winter as compared withdeciduous trees in boreal forests. Therefore, photooxidative stress plays a key role in the reproductive strategy,
survival strategy and biodiversity of trees in the boreal forest. We will talk about the molecular and ecologicalmechanisms of how photooxidative stress affects the dynamics of boreal forests with reference to climatechange.

Session 2. Poster Session

2-1

Photosystem Development of Marine Cyanobacterium Prochlorococcus
Hisashi Ito, and Ayumi Tanaka
Institute of Low Temperature Science, Hokkaido University
ito98@lowtem.hokudai.ac.jp

We analyzed the Synechocystis sp. PCC6803 transformant to understand the development of Prochlorococcus
photosystem. Two genera of marine cyanobacteria, Prochlorococcus and marine Synechococcus, are abundantin the oceanic waters. Prochlorococcus is considered to be derived from marine Synechococcus.
Prochlorococcus genus is dominating to a latitudinal belt of the oceans bounded by the latitudes around 45ºN to
40ºS. In contrast, marine Synechococcus is found in the ocean ubiquitously up to the polar circle. Thesecyanobacteria contribute significantly to primary production in the ocean. Higher plants and cyanobacteria
possess monovinyl chlorophyll. However, Prochlorococcus possesses divinyl chlorophyll, of which C-8 vinylgroup is not reduced to ethyl group. The presence of divinyl chlorophyll is a trait common to all
Prochlorococcus strains. We used model freshwater cyanobacterium Synechocystis sp. PCC6803 as the material.
The structure of the main components of the photosynthetic apparatus of Synechocystis sp. PCC6803 is similar
to that of marine Synechococcus. Divinyl chlorophyll accumulated in Synechocystis sp. PCC6803 by the
disruption of the essential gene in the reduction of divinyl chlorophyll to monovinyl chlorophyll. The
transformed Synechocystis sp. PCC6803 was photosensitive. When the conserved amino acid residues in
Prochlorococcus were introduced into the chlorophyll protein of the transformant, photosensitivity was
suppressed. These observations suggest that modification of both chlorophyll and chlorophyll protein is criticalin the branching of Prochlorococcus with Synechococcus. The intermediate of Synechococcus andProchlorococcus would be photosensitive. We could expect that this is the reason why we can not find theintermediate in the ocean now.

2-2

Delayed Leaf Senescence by Enhanced Chlorophyll b Biosynthesis
Yasuhito Sakuraba, Ryouichi Tanaka, and Ayumi Tanaka
Institute of Low Temperature Science, Hokkaido University
rtanaka@lowtem.hokudai.ac.jp

Leaf senescence is not merely termination of cellular activities at the end of the plant life cycle: upon leaf
senescence, plant cells execute a genetically encoded program that defines the order and the timing of multiple
specific cellular processes. These processes are prerequisite for recovering cellular resources (sugars, aminoacids and other nutrients) and transfer them to storage organs such as seeds. Since these processes should be
conducted in multiple organelles within a cell, it would be reasonable to assume that the progresses of theseprocesses are monitored by the cell itself (or by the nucleus) and in turn, the nucleus exerts a certain control overthese organelles by means of gene expression. In other words, it is likely that the organelles communicate eachother to proceed multiple events in leaf senescence in a coordinated way. Several mechanisms for such
intracellular communication have been proposed: tetrapyrrole metabolism is one of the hypotheses to explain
intracellular communications. Here, we report that a modification of chlorophyll metabolism led to delayed leaf
senescence, which phenomenon may involve a communication between the chloroplast and the nucleus. In thisstudy, we analyzed a transgenic Arabidopsis plant that overexpressed chlorophyllide a oxygenase (CAO), an
enzyme responsible for chlorophyll b biosynthesis. We incorporated a modification of the CAO sequence(deletion of the N-terminal domain), which liberated this enzyme from its regulatory mechanism, leading toexcess accumulation of chlorophyll b in the transgenic plant. Under continuous illumination, the leaves of thewild-type Arabidopsis plant turned yellowish after 7 weeks of germination, while the leaf yellowing of the
CAO-overexpressing plant delayed one week to that of the wild type plant. The decrease in the CO2 uptake wasalso slowed down in the CAO-overexpressing plant during senescence, indicating that enhanced chlorophyll b
biosynthesis affected not only chlorophyll-b binding LHC proteins but also the entire process of photosynthesis.
Simultaneously, the steady state levels of Lhcb1, HemA1 and RbcS were maintained at a high level in the
CAO-overexpressing plant at this stage, while the steady state level of SAG12 mRNA, which is a good indicatorof the onset of leaf senescence, was lower than that of wild type. These results indicate that enhanced
chlorophyll b biosynthesis modified the cellular program and delayed leaf senescence. We will discuss possible
mechanisms that mediate the communication between the chloroplast and the nucleus during leaf senescence.

2-3Ecophysiological Responses of Abies sachalinensis Seedlings to Two
Contrasting Environments in a Sub-boreal Forest of Hokkaido, Japan
Edgard A. Bontempo e Silva 1, Toshihiko Hara 1, Akihiro Sumida 1, Kyomi Ono 1, Yuji Kodama 1, Taro Nakai 1,
and Shigeru Uemura 2
1
Institute of Low Temperature Science, Hokkaido University
2
Field Science Center for Northern Biosphere, Hokkaido University
silva@pop.lowtem.hokudai.ac.jp

In cold climate areas canopy coverage can protect seedlings from environmental stresses such as radiant frost
and cold-induced photoinhibition. The comprehension of how plants respond to such pressures in the event of a
canopy opening, or when colonizing an open area, is important to explain the present species distribution and to
predict shifts in forest dynamics in response to climate change.
The influences of environmental conditions on the photosynthesis of Abies sachalinensis (Sakhalin Fir)
seedlings at two contrasting sites, under a deciduous canopy and in a wide canopy gap, were studied by making
photosynthetic light curves, measuring chlorophyll fluorescence, growth, soil temperature, soil water content,
nitrogen content, and gathering meteorological data. The measurements were made from September 2007 to
May 2009, at the Uryu Experimental Forest of Hokkaido University.
Seedlings were photoinhibited in both sites in May and June, but at the open canopy site the photoinhibition
persisted until late July. Abies growing at the closed canopy site showed a greater degree of photoinhibition thanthose at the open canopy site, but recovered quickly after the canopy's new leaves flushed, reflecting its
acclimation to the shaded condition. Although chlorophyll fluorescence values were positively correlated tophotosynthetic rates, seedlings showed statistically similar photosynthetic rates at both sites during most of thegrowing season. This species' ecophysiological responses and acclimation capacity at seedling stage can help to
explain its life history strategy and role in Hokkaido's sub-boreal forest dynamics.

2-4

Effects of Soil Water Conditions on the Morphology, Phenology andPhotosynthesis of Betula ermanii in the Boreal Forest
Azusa Tabata, Kiyomi Ono, Akihiro Sumida, and Toshihiko Hara
Institute of Low Temperature Science, Hokkaido University
atabata@pop.lowtem.hokudai.ac.jp

Betula ermanii is an early-successional tree species which is widely distributed over subalpine forests in Japanand other regions of boreal forest zone. To investigate the effects of low soil water content on photosynthesis
and photoprotective responses of leaves and on whole-plant growth of 4-year-old B. ermanii seedlings, four2-year watering treatments were applied to B. ermanii seedlings: ID (irrigated well (I) in the previous year andwater deficit (D) in the current year), DD, DI, and II. Relative growth rate (RGR) of the seedlings was smaller incurrent-year water deficit without experiencing previous-year water deficit (ID) than in irrigated well in both
years (II). Surprisingly, RGR did not differ significantly between two-year-water-deficited (DD) and-well-irrigated (II) treatments. The difference in area-based photosynthetic rate of the late leaves (= leaves
formed in the current year environment) was not significant between the four water treatments, but their leaf
longevity was shortened by water deficit. As for the early leaves (buds of which formed in the previous year
environment) the photosynthetic rate was smaller in ID than in II, but it did not differ between DD and II. Leaf
mass per area (LMA = leaf dry weight / leaf area) did not differ among the four water treatments. Specific root
length (SRL = root total length / root dry weight) did not differ between ID and II. It was greater in DD than in II,
probably resulting in increased water uptake efficiency under two-year water deficit conditions. Photoprotective
systems such as xanthophyll contents and antioxidant enzyme activities did not differ among the four treatments.
Morphological responses of B. ermanii roots (SRL) seem to be important as whole-plant-level responses towater deficit for maintaining RGR, in addition to leaf-level photosynthetic and phenological responses of two
types of leaves. Our results partly explain how B. ermanii seedlings can survive and maintain growth evenunder varying soil water conditions in the boreal forests.

2-5Insect Immunity: Solution Structure of the Silkworm ßGRP N-terminal Domain
Reveals the Mechanism for ß-1,3-glucan-specific Recognition
Masanori Ochiai 1, Kiyohiro Takahasi 2, and Fuyuhiko Inagaki 2
Institute of Low Temperature Science, Hokkaido University
2
Graduate School of Pharmaceutical Sciences, Hokkaido University
ochiai@lowtem.hokudai.ac.jp
1

Infection by a variety of pathogens such as Gram-positive and Gram-negative bacteria, fungi, viruses andparasites evoke a host-defense system termed innate immunity. Activation of innate immunity by
micro-organisms is initiated by pathogen-associated molecular patterns including peptidoglycan,
lipopolysaccharide, and ß-1,3-glucan, components of microbial cell walls recognized by pattern-recognition
proteins. Insects lack adaptive immunity, and here innate immunity is the sole defense system against pathogens
and has a crucial role in host survival. The ß-1,3-glucan recognition protein (ßGRP) is a crucial
pattern-recognition protein that specifically binds ß-1,3-glucan, a component of fungal cell walls. It evokes
innate immunity against fungi through activation of anti-microbial defense systems such as theprophenoloxidase (proPO) cascade and Toll signaling pathway for the expression of antimicrobial peptides in
insects. The ßGRP consists of an N-terminal ß-1,3-glucan recognition domain and a C-terminal glucanase likedomain, with the former reported to be responsible for the proPO cascade activation.
To elucidate the functional mechanism of the ß-1,3-glucan recognition, the solution structure of the N-terminal
ß-1,3-glucan recognition domain of silkworm ßGRP was determined by NMR. Although the N-terminal
domain of ßGRP has a ß-sandwich fold, often seen in carbohydrate-binding modules, both NMR titration
experiments and mutational analysis showed that ßGRP has a unique binding mechanism which is distinct fromthose observed in previously reported carbohydarate-binding domains. Our results suggest that ßGRP is a novel
ß-1,3-glucan recognition protein that specifically recognizes a triple-helical structure of ß-1,3-glucan.

2-6

Molecular Characterization of Photosynthetic Protein Complexes of Marine
Diatoms
Ryutaro Tokutsu, and Jun Minagawa
Institute of Low Temperature Science, Hokkaido University
tokutsu@pop.lowtem.hokudai.ac.jp

Diatom (Bacillariophyceae) is one of the most successful taxonomic groups of organisms throughout theworld’s ocean and fresh water. They contribute nearly 25% of global production, which is comparable to that of
all terrestrial rain forests. Hence, diatom has been recognized as an important photosynthetic organism in thebiochemical carbon cycles. Due to their ecological significance, the complete nuclear and chloroplast genomeof a centric diatom, Thalassiosira pseudonana, and a pennate diatom, Phaeodactylum tricornutum had been
revealed as model diatoms.
We are studying the molecular details of photosynthetic protein-pigment complexes of T. pseudonana and P.
pseudonana as a model of centric and pennate diatoms, respectively. At first, thylakoid membranes wereobtained after disruption of the cells, and the β-dodecyl maltoside was used for mild solubilization of thethylakoid membranes. The solubilized thylakoids were subjected to sucrose density gradients, followed by gel
filtration to purify the photosynthetic pigment-protein complexes. Presented herein are data on the compositionsof each photosynthetic protein complexes by biochemical analyses, spectroscopic measurements, and MS/MS
identification, revealing the differences of living strategies between these diatoms. To our knowledge, this is thefirst molecular characterization and comparison of two representative diatoms.

2-7Community Structure of Methane-oxidizing Bacteria in Water Column of aFreshwater Lake
Masazumi Tsutsumi 1, Hisaya Kojima 1, Tomoya Iwata 2, and Manabu Fukui 1
1
Institute of Low Temperature Science, Hokkaido University
2
Department of Ecosocial System Engineering, University of Yamanashi
tsutsumi@pop.lowtem.hokudai.ac.jp

Most of the methane produced in anoxic sediment of freshwater lakes is consumed in oxic sediment and/or
water column. This consumption is attributed to activity of aerobic methane-oxidizing bacteria (MOB), which
oxidize methane with oxygen. Known methane-oxidizing bacteria were classified into more than 13 genera.
Vertical changes in community composition and abundance of MOB were analyzed in water column of a
freshwater lake. This lake is characterized by permanent stratification and the temperature of the lower layer
was kept at approximately 5 ºC through a whole year. Almost all detected MOB were closely related to
psychrophilic or psychrotolerant species belonging to one genus. However, the community compositions of
MOB in water column were different between the upper and lower water depths. Around the boundary of theshift of these compositions, physicochemical factors were shifted dramatically and MOB were the mostabundant among all water depths.

2-8Weta Lipophorin – Comparison with other Insects –Y. Kato, M. Iwasaki, M. Ochiai, K. Shimada, and C. Katagiri
Institute of Low Temperature Science, Hokkaido University
gotohy@lowtem.hokudai.ac.jp

Weta, an endemic orthopteran in New Zealand, overwinters in every life stage; egg, nymph, and adult. At theend of 2006, we started the biochemistry of weta, concerning its tolerance to low temperature. We report thecharacterization of weta lipophorin, a major lipoprotein in insect hemolymph. Lipophorin is known as areusable shuttle to transport various lipids ; diacylglycerol, unesterified cholesterol, and hydrocarbons. It
transports lipids between the sites of storage, synthesis and absorption, and the tissues that use lipids as energies
or as structural components. Its molecular mass is about 600 kDa, and it has two apolipoproteins;
apolipophorins (apoLp)-I and -II. Some insects have another apolipoprotein, apoLp-III, which attaches to thesurface of lipophorin to transfer more diacylglycerol as fuel during long distance flight.
We isolated and purified lipophorin from the adult hemolymph of two weta species ; tree weta (Hemideina
femorata) living in plains, and alpine weta (Hemideina maori) living in mountainous area. We compared thelipophorin from wetas with that from cricket adults (Gryllus bimaculatus) and silkworm larvae (Bombyx mori).
SDS-PAGE showed that weta has apoLp-I and II, but apoLp-III wasn’t detected. We also characterized the lipid
composition of weta lipophorin. Weta lipophorin has only saturated hydrocarbons. In comparison withsilkworm lipophorin, weta lipophorin has higher percentage of phosphatidylcholine and lower percentage of
diacylglycerol in the total lipids.

Acknowledgments---We thank Drs. H. Nishino (Hokkaido University) and L. H. field (University ofCanterbury) and D. A. Wharton (University of Otago) for helping us to collect wetas.

2-9Stable Oxygen Isotope Ratio of Sea Water and its Spatial Distribution at theContinental Margin of Antarctica
Shigeru Aoki 1, Mikio Naganobu 2, Takashi Ishimaru 3, Stephan R. Rintoul 4, Nathaniel L. Bindoff 5, andKeiichiro Ohshima 1
1
Institute of Low Temperature Science, Hokkaido University
2
Fisheries Research Agency
3
Tokyo University of Marine Science and Technology
4
CSIRO
5
University of Tasmania
shigeru@lowtem.hokudai.ac.jp

Salinity is the key variable that controls the sea water density in the polar oceans. Recently, long-term salinitychanges of Antarctic waters have been reported in a few regions and they can have a significant impact on the
global meridional overturning circulation. To examine the causes of the changes, it is useful to monitor stable
oxygen isotope ratio (δ18O) as well as salinity. To determine the spatial distribution and set a baseline for the
future state, intensive δ18O observations have been made. More than five cruises from 2005 were conducted byAustralia and Japan in the Ross Sea, Australian-Antarctic Basin, and Weddell-Enderby Basin. Waters on the
Antarctic continental shelf region are processed and described.
Salinity- δ18O relationship of most Antarctic Surface Water and Winter Water is aligned on the same
Melting-Freezing lines, possibly reflecting the near-surface sea ice formation/melting processes. Significantly
isotopically light waters are found at some locations, revealing the melting of land ice. In the Ross Sea, HighSalinity Shelf Water/Ice Shelf Water in the western region are isotpoically depleted, and Low Salinity Shelf
Water in the eastern region is even lighter. This suggests a relatively strong influence of land ice in the easternregion. Long-term salinity- δ18O change in High Salinity Shelf Water is consistent with that due to land ice
melting, when combined with the historical data set of Jacobs et al. (2002). At the Adelie Depression where thesource of the Adelie Land Bottom Water is located, High Salinity Shelf Water is relatively isotopically heavy.
This may reflect a relatively short residence time in the Depression. At the eastern mouth of Prydz Bay,
isotopically light High Salinity Shelf Water is found.
As such the δ18O is a useful indicator in defining the freshwater budget and the sustained observations of δ18O
will surely contribute to the further understanding of the Antarctic climate change.

2-10Size Distribution of Sea Ice Floes in the Antarctic Marginal Ice Zones in Late
Winter1

Takenobu Toyota 1, Christian Haas 2, and Takeshi Tamura 1
Institute of Low Temperature Science, Hokkaido University
2
University of Alberta
toyota@lowtem.hokudai.ac.jp

In the marginal sea ice zone (MIZ), where relatively small ice floes are dominant, floes size distribution is an
important parameter to a melting process because smaller ice floes are subject to stronger lateral melting due totheir larger perimeters. However, the available data have been very limited so far. The analysis of the Okhotsk
sea ice revealed that while floe size distribution is basically scale invariant, regime shift occurs at a size of about
40 m. In order to extend this preliminary result to the Antarctic MIZ, the ice floe size measurements wereconducted in the northwestern Weddell Sea and off Wilkes Land with a heli-borne digital video camera in late
winters of 2006 and 2007. The floe size analyzed ranges from 2 m to 100 m. In the same region, ice thickness
measurements were also performed to examine the controlling factor. The analysis shows: 1) the scale
invariance and regime shift are confirmed in both regions; 2) the floe size at which regime shift occurs slightly
increases from 20 to 40 m with ice thickness, consistent with the theory of flexural failure of sea ice; and 3) the
aspect ratio is 1.6-1.9 on average, close to the previous results. For floes smaller than 2 m, a field measurement
was conducted for ice pieces stranded on the seashore facing the southern Sea of Okhotsk as an alternative inthe same season. It is found that such small ice pieces are affected more by melting and grinding. Based on theseresults, the formation process of size distribution and its effect on a melting process are discussed.

2-11

Stable Hydrogen Isotopic Compositions of n-alkanes in Atmospheric Aerosols
from Tokyo as a Potential Tracer to Decipher the Source Region Tracer of
Terrestrial Plant Waxes
Yamamoto, S., and Kawamura, K.
Institute of Low Temperature Science, Hokkaido University
s.yamamoto@pop.lowtem.hokudai.ac.jp

A long-range atmospheric transport of terrigenous organic materials to the open ocean is one of the important
pathways in global carbon cycle. Studies on molecular composition and compound-specific carbon isotopic
ratio (δ13C) of leaf wax n-alkanes in atmospheric aerosols have revealed details of their long-range atmospherictransport over the south Atlantic and western Pacific Oceans. However, molecular and δ13C compositions ofterrestrial plant waxes in the eastern part of the Asian continent are relatively constant reflecting C3-dominatedvegetation, which makes it difficult to specify the source regions of plant materials in the atmospheric aerosols
over the East Asia and northwest Pacific regions. Recent observation displays a large (>100‰) spatial variationin hydrogen isotopic composition (δD) of rainwater in East Asia. Because δD values of terrestrial higher plants
sensitively reflect those of precipitation waters, δD of leaf waxes are expected to provide information on theirsource region. In this study, we measured the δD of n-alkanes in atmospheric aerosols from Tokyo to better
understand the origin of leaf wax n-alkanes in atmospheric aerosols. The δD values of fossil fuel n-alkanes (C21
to C24) in Tokyo aerosols range from –65 to –94‰, which are within the range of those reported in marine crude
oils. In contrast, the δD of longer chain (C29 and C31) n-alkanes (δDLA) show much lower values by ~70‰ thanthose of fossil fuel n-alkanes. Their values were found to exhibit concomitant variations with carbon preference
index (CPI), suggesting that the δDLA reflect the δD of leaf wax n-alkanes with a variable contribution fromfossil fuel n-alkanes. Nevertheless, a good positive correlation (r = 0.89, p < 0.01) is found between the δDLA
and CPI values, which enables us to eliminate the contribution of fossil fuels using a mass balance approachwith an assumption that CPI of fossil fuel is 1 and CPI of plant waxes is 5-15. Calculated n-alkane δD values
averaged from –163 to –178‰ for C29 and from –159 to –172‰ for C31. These values are consistent with thosereported from growing leaves in Tokyo, which confirms the usefulness of the δD of long chain n-alkanes as a
tracer for the source region of terrestrial plant waxes in atmospheric aerosols.

2-12Detection of Organized Airflow Structure in the Atmospheric Boundary Layer
Using a 3D-scannnig Doppler Lidar

1

Chusei Fujiwara 1, Kazuya Yamashita 1, and Yasushi Fujiyoshi 2
Graduate School of Environmental Science, Hokkaido University
2
Institute of Low Temperature Science, Hokkaido University
chuchu@lowtem.hokudai.ac.jp

The organized airflow structures in the atmospheric boundary layer (ABL) are responsible for verticaltransportation of most of the turbulent fluxes of momentum, buoyancy and material. Within the ABL, plants andmost animals, including human beings spend most of their lives. An understanding of organized structures in the
ABL is therefore crucial for directing future development not only in meteorological and climate modeling but
also in wind engineering, environmental science, disaster science, urban engineering and bionomics. Using a
3D-scanning coherent Doppler lidar (3D-CDL), we succeeded in detecting various kinds of atmosphericphenomena such as streaks, fish nets, invisible dust devils and wake of building. Some of these phenomena
were observed for the first time through the use of 3D-CDL. In addition, we simulated some of these
phenomena by using Large Eddy Simulation and results obtained were compared with those observed by the
3D-CDL.

2-13

Changes in the Sea of Okhotsk due to Global Warming– Weakening Pump Function to the North Pacific –Takuya Nakanowatari, and Kay I. Ohshima
Institute of Low Temperature Science, Hokkaido University
nakano@lowtem.hokudai.ac.jp

The Sea of Okhotsk is the southern limit of sea ice in the Northern Hemisphere. This is because the cold pole in
the Northern Hemisphere is located in the upwind region of the Sea of Okhotsk. When sea ice is formed, mostof the salt content is rejected from the ice and thus cold, saline and dense water is released into the ocean below.
Since large amounts of sea ice are formed in the Sea of Okhotsk, the densest water on the surface of the North
Pacific is produced there. Sinking of this dense water creates the vertical circulation (overturning) down to theintermediate depths (approx. 200 to 800 m deep) in the North Pacific. The Okhotsk thus plays a role as thepump of the North Pacific. We found that the water temperature in the intermediate layer of the Okhotsk has
increased over the past five decades while the oxygen has decreased. This means that sinking of cold
oxygen-rich surface water into the intermediate layer has decreased. These signals have spread to the North
Pacific along the pathway of the seawater flowing out of the Okhotsk. The Okhotsk is a sensitive area to global
warming: the wintertime air temperature has significantly increased and sea ice extent has decreased by about
20% for the past three decades. We propose that decrease of sea ice production caused the decline in densewater sinking, leading to the weakening of overturning in the North Pacific. The weakened overturning possibly
affects the iron circulation, since the iron in the western North Pacific presumably originates from the dense(intermediate) water from the Okhotsk, further from the Amur River. Recent studies suggest that iron is a
substantial factor in determining biological productivity. Current global warming, through sea ice reduction,
might decrease the iron supply in the North Pacific as well as in the Okhotsk, thus reducing levels of biologicalproductivity and fishery resources.

2-14

Direct Observations of Newly-found Antarctic Bottom Water and the
Associated Sea-ice Production - Cape Darnley Project Yasushi Fukamachi 1, Kay I. Ohshima 1, Shigeru Aoki 1, Daisuke Simizu 1, Takeshi Tamura 1, Yujiro Kitade 2,
Daisuke Hirano 2, Shuki Ushio 3, and Gen Hashida 3
1
Institute of Low Temperature Science, Hokkaido University
2
Faculty of Marine Science, Tokyo University of Marine Science and Technology
3
National Institute of Polar Research)
yasuf@lowtem.hokudai.ac.jp

Global deep ocean circulation is essentially driven by dense waters (North Atlantic Deep Water and Antarctic
Bottom Water) produced and sunk in the North Atlantic and Southern Ocean. For the formation of such densewaters, saline water rejected during sea-ice formation is an essential component. In the Southern Ocean, sea
ice is mainly formed in open and thin-ice areas (called polynyas) near the continent, and the Weddell and Ross
Seas, and the region off the Adelie Land are known as the three main production sites of Antarctic Bottom
Water (AABW).
Using the satellite sea-ice data and objectively-analyzed meteorological data, Tamura et al. (2008) estimatedsea-ice production in the entire Southern Ocean. They revealed that a polynya off the Cape Darnley northwestof the Amery Ice Shelf has the second highest production rate next to a polynya in the Ross Sea. This factsuggests that the Cape Darnley Polynya is possibly another important AABW production site.
To examine this hypothesis, we conducted hydrographic and mooring observations in this area in 2008-2009.
Hydrographic data reveal the existence of thick AABW layer along sections downstream (westward) of theCape Darnley Polynya. Time-series data at the moorings downstream of this polynya show that high density
signals appeared in April and May following the onset of sea-ice formation in this polynya. These data clearly
indicate that AABW is locally formed due to the high salinity water produced in the Cape Darnley Polynya.
Following our pilot experiment in 2008-2009, we are going to expand our observations in the framework of theJapanese Antarctic Research Expedition in next four years. We are planning to measure sea-ice production
directly within the polynya in 2010-2011 and 2012-2013 by mooring ice-profiling sonars, and evaluate thevolume transport of the AABW export in 2011-2013 by an array of current-meter moorings.

2-15

Mapping of Sea Ice Production in the Southern Ocean
Takeshi Tamura, Kay I. Ohshima, and Sohey Nihashi
Institute of Low Temperature Science, Hokkaido University
tamutake@lowtem.hokudai.ac.jp

Most of coastal polynyas are latent heat polynyas, which are formed by the divergent ice motion due toprevailing winds or oceanic currents. Salt rejection due to active sea ice formation there produces dense water,which can be a source of bottom or intermediate water in the world ocean. Antarctic coastal polynyas are
responsible for Antarctic Bottom Water (AABW) formation. Because in-situ observation of coastal polynyas isextremely difficult, detection of polynya areas by use of satellite data are very useful way for the investigation ofcoastal polynyas. This study gives the first mapping of sea ice production in the Southern Ocean from thesatellite microwave data and heat flux calculation, and discusses the spatial distribution of sea ice production
and interannual variability of the production.
We develop an algorithm that estimates thin ice thickness in coastal polynyas from the SSM/I data, based on thecomparison with ice thickness estimation from the AVHRR data. This algorithm uses 37 and 85 GHz brightness
temperature data, and can also detect large icebergs and landfast ice. Using thin ice thickness distribution
derived from this new algorithm and surface input data from the ECMWF Re-Analysis, heat flux calculation is
performed on a daily basis and we estimate sea ice production under the assumption that heat loss in polynyas
are assumed to coincide with the ice production, ignoring the effect of oceanic heat flux from below.
The highest ice production area in the Southern Ocean is the Ross Ice Shelf Polynya, which is consistent withthe production area of AABW with the highest salinity. Along the coast of East Antarctica, high ice production
areas of coastal polynyas appear on the west side of peninsulas and glacier tongues, downstream of the Antarctic
Coastal Current. It is noted that the second highest ice production area is the Cape Darnley polynya west side ofPrydz Bay, suggesting the bottom water formation there. Highest interannual variability in the production isfound in the Ross Sea among the Antarctic coastal polynyas. The ice production there has decreased by 30%
from the 1990’s to 2000’s, which may be a candidate for a recent change of the bottom water there. According
to our estimation, around 10% of Southern Ocean sea ice is produced in the major Antarctic coastal polynyas.
The mapping provides surface heat- and salt-flux conditions in the ice-covered region, which have not been
well understood.

2-16

Evaluation of Snowfall Interception of Boreal Forest
Tomoyasu Kuno 1, Yuji Kodama 2, and Taro Nakai 3
1
Graduate School of Environmental Earth Sciences, Hokkaido University
2
Institute of Low Temperature Science, Hokkaido University
3
International Arctic Research Center, University of Alaska
kuno@pop.lowtem.hokudai.ac.jp

Introduction Snowfall interception by canopy is an important factor for the variation of snow waterequivalent (SWE) of snowy forest watershed. Intercepted snow stays on canopy from several days to a few
months, a part of which eventually evaporates back to atmosphere or falls down to ground. The fallen snow
from the canopy becomes a part of snowpack on the ground, and the sublimated snow becomes a loss toprecipitation. Therefore, it is important to estimate the amount evaporation loss of the intercepted snow. This
research aims to evaluate the interception loss by measuring the snow water equivalent inside and outside aboreal forest and discusses on the seasonal variation of the interception coefficient, and their relationship with
canopy density and atmospheric conditions.
Observation site and method The observation was carried out at a mixed forest of coniferous and broad leaf
trees and a birch forest in the Uryu Research forest of Northern Biosphere Field Research Ceter, Hokkaido
University from November 2007 to March 2008. The SWE of inside and outside of forest, canopy sky view
factor (SVF), profiles of sublimation from a block of ice are observed with meteorological terms by boundary
layer tower. A snow survey was carried by setting a 5 meter grid in a plot of 50 m x 100 m.in the mixed forest,and line measurement of 50 m with 1m interval at the open site. Sublimation profiles ice was measured bymeasuring the weight change of a block of ice, which hung at several heights on the tower.
Discussion and results The difference in SWE of inside and outside of forest is small at the Birch forest sitethrough the observation period and at the Mixed forest site, it was small in early winter but became larger
towards the end of the observation period. The average interception loss is 14.4% for Mixed forest and 7.8%
for Birch forest.
The SWE inside the Mixed forest increased with sky view factor (SVF), and the interception fraction is closely
related to the canopy density. The SVF within the zenith angles less than 60 degree is better assessed theabove result than the SVF within the zenith angle less than 10 degree, therefore, the SWE is related to the
canopy density not just above canopies but with wider area.
The profiles of evaporation from ice blocks showed larger rate with height for the period longer than 1 week.
This is mainly due to the wind and specific humidity profiles. This result must be concerned in snowfallinterception models.

2-17

Continuous Measurement of Carbon Dioxide and Methane Concentration
using 9-Tower Network over Siberia

M. Sasakawa 1, K. Shimoyama 2, T. Machida 1, N. Tsuda 3, H. Suto 4, M. Arshinov 5, D. Davidov 5,
A. Fofonov 5, O. Krasnov 5, T. Saeki 1, Y. Koyama 1, and S. Maksyutov 1
1

Center for Global Environmental Research, NIES
Institute of Low Temperature Science, Hokkaido University
3
Global Environmental Forum
4
Japan Aerospace Exploration Agency
5Institute of Atmospheric Optics of SB RAS
sasakawa.motoki@nies.go.jp, k-shimo@lowtem.hokudai.ac.jp
2

Continuous measurements of CO2 and CH4 mixing ratios have been carried out with a tower network in Siberia
in order to study the spatial and temporal variations of these trace gases in the forest, steppe, and wetland regions
and estimate the distribution of their fluxes over this huge area where only few atmospheric investigations were
made. The network consists of 9 towers located at Berezorechka (BRZ; 56.09'N, 84.20'E) since 2002, at
Karasevoe (KRS; 58.15'N, 82.25'E) and Igrim (IGR; 63.11'N, 64.25'E) since 2004, at Demyanskoe (DEM;
59.47'N, 70.52'E), Noyabrsk (NOY; 63.26'N, 75.47'E) and Yakutsuk (YAK; 62.50'N, 129.21'E) since 2005, at
Savvushka (SVV; 51.20'N, 82.08'E) since 2006, at Azovo (AZV; 54.42'N, 73.02'E) since 2007, and at
Vaganovo (VGN; 54.30'N, 62.19'E) since 2008. Air samples taken at two heights (5-85 m) on each tower are
analyzed with a NDIR (LI-COR, LI-820) for CO2 and SnO2 semiconductor sensor for CH4 after passing
through the line with a glass water trap, a Nafion membrane drier and a magnesium perchlorate.
Seasonal maximum of daytime mean CO2 (13:00-17:00 local time determined by geographical location)
occurred in mid-winter (Dec.-Jan.) due to temporally observed high concentration more than 390 ppm. The
high concentration spell seemed to be associated with the Siberian high because strongly suppressed verticalmixing in the anticyclonic field resulted in the accumulation of anthropogenic and biospheric CO2 sources in thesurface layer. Remarkable CO2 drawdown started almost simultaneously around the beginning of May at thewestern Siberian sites. Seasonal minimum occurred during the summer (Jun. – Aug.) and showed latitudinaldifference (~ 6 ppm) as lower values in the southern sites, which obviously reflected the distribution of CO2
sequestration by Siberian boreal ecosystem. Mean seasonal CO2 amplitudes from 2002, 2004 and 2005 to2007 were 32.4, 33.3, 29.8, 28.4, 28.4 and 29.5 ppm in BRZ, KRS, IGR, DEM, NOY and YAK, respectively,
which were rather large compared with the data from the coastal sites at similar latitude as Siberia (Fig. 2).
Furthermore, ranging from 20 to 30ppm of amplitude was occurred during growing season. These results
strongly suggested that important rolls of Siberian ecosystem on atmospheric CO2. The seasonal amplitude
remarkably differed (~8 ppm) year-by-year, which depended not only on the summer but also on magnitudeand frequency of high-CO2 event due to Siberian high during winter.
Siberian daytime mean CH4 always shows heiger concentration than that of the NOAA sites andcharactaristically have double seasonal peak (winter and summer). Contribution of CH4 from wetlands
calculated with the Lagrangian particle dispersion model FLEXPART, which releases 10000 particles from eachmonitoring site, is the largest during summer among several potential sources (animal, landfill, coal mining etc),
which suggests that CH4 emission from wide spread wetlands over the northwestern Siberia caused summer
CH4 peak. Higher mixing ratio than that of the coastal sites even during winter implies that unknown CH4
source keeps the mixing ratio high. Synoptic CH4 feature over Siberia will be clarified more using this9-tower network and CH4 budget calculation in continental scale will be done with the coming data in the near
future.

2-18

Energy Transfer in a Breaking Internal Wave
Shoko Abe 1, 2, and Tomohiro Nakamura 2
1
Graduate School of Environmental Science, Hokkaido University
2
Institute of Low Temperature Science, Hokkaido University
abe-s@lowtem.hokudai.ac.jp

Strong vertical mixing in the Kuril Island Chain is one of important physical processes because it affects
changes in water properties and the strength of the thermohaline circulation in the Sea of Okhotsk, which is
known as an origin of North Pacific Intermediate Water. It is thought that it influences not only physicalprocesses but also distributions of materials, such as iron, and the ecosystem in the surrounding area. It isconsidered that the vertical mixing in the region is caused by breaking of large-amplitude internal waves
induced by the K1 tidal flow. Although the construction of realistic parameterization schemes for global
circulation models, which cannot explicitly resolve such mixing, needs an understanding of the detail of themixing, processes after breaking are unrevealed because of their nonlinearity. Therefore, to clarify the verticalmixing processes, we attempted to simulate transition from breaking of an internal wave to turbulent state using
a two-dimensional non-hydrostatic model with a realistic topography, and investigate the energy transfer
associated with the processes.

2-19

Iron Flux to the Northern North Pacific Estimated from the Ice Core of Mt.
Wrangell, Alaska

1

Hirotaka Sasaki 1, Sumito Matoba 2, and Takayuki Shiraiwa 3
Graduate School of Environmental Science, Hokkaido University
2
Institute of Low Temperature Science, Hokkaido University
3
Research Institute for Humanity and Naturehsasaki@pop.lowtem.hokudai.ac.jp

We measured iron concentration in an ice core (50 m) drilled in 2003 at Mt. Wrangell, Alaska which located thelee of the transport path of the Kosa. The ice core recoveres 1992 to 2003 and the iron concentration peak
appeared in spring every year. These peaks may reflect the Kosa event in spring. And we calculated the iron fluxof each peak, and estimated the impact to the iron concentration of the ocean. The iron flux of maximum peaks
can increase the iron concentration of the ocean twice.
Introduction
The northern North Pacific Ocean is one of the High Nutrient Low Chlorophyll (HNLC) ocean areas where
biological productivity is low for high nutrient. Martin (1990) hypothesized that the iron plays a key role inphytoplankton growth in these areas. Kosa is the huge dust storm that occurs in the East Asian Continent andincludes the iron as basis. It is deposited into the northern North Pacific Ocean region while on a transporting
through this area. To make out the iron flux that deposited from the atmosphere, we measured high resolution
iron concentration of the ice core drilled at Mt. Wrangell, Alaska in 2003.
Iron concentration profile
We measured iron concentration in the ice core from 0 to 50 m. Yasunari et al. (2007) estimated that the ice core
recoveres 1992 to 2003. The profile of iron concentration shows that high concentration appeared in every
spring from 1992 to 2003. Especially, remarkable high concentrations were shown in 2001 and 2002 whendrastic Kosa phenomena in spring were observed in Japan. Accordingly, we suggest the iron profile of the icecore reflect on the variation of the dust flux from the Asian Continent.
Iron flux from atmosphereWe calculated iron flux from the iron concentration in the ice core sample from the length and the density of theice core sample. The iron fluxes in spring from 1992 to 2000 ranged 2.8-9.3 mg/m2/yr. These values arecomparable to the iron fluxes estimated by Duce and Tindale (1991), and Mahowald et al. (2003). We assume
that one peak of iron concentration observed in 2001 and 2002 correspond to one Kosa event. The average ofiron fluxes of each Kosa event in 2001 and 2002 was 10 mg/m2/yr.
The impact to the ocean’s iron concentration
Several previous works showed that dissolved rate of air-borne iron in the ocean was 2-10 %. The depth ofvertical mixing layer in winter at the northern North Pacific is approximately 30 m (Nishioka personalcommunication). If we assumed that 2 % of airborne iron can be dissolved in surface 30 m of ocean, 0.13 nM ofiron can be dissolved from 10 mg/m2 of air-borne iron flux, and can increase the concentration of iron in ocean

twice.

References:
Duce, R. A. and N. W. Tindale (1991), Atmospheric transport of iron and its deposition in the ocean, Limnol.
Oceanogr., 36, 1715-1726.
Mahowald, N. M. and Chao Luo (2003), A less dusty future? Geophys. Res. Lett., 30, 1903.
Martin, J. (1990), Glacial-Interglacial CO2 Change: The Iron Hypothesis, Paleoceanography, 5, 1-13.
Sasaki, H. (2008), Iron flux to the northern North Pacific estimated from the ice core of Mt. Wrangell, Alaska,
M. S. thesis., Hokkaido University, Sapporo.
Yasunari, T. J., T. Shiraiwa, S. Kanamori, Y. Fujii, M. Igarashi, K. Yamazaki, C. S. Benson and T. Hondoh(2007), Intra-annual variations in atmospheric dust and tritium in the North Pacific region detected from an
ice core from Mount Wrangell, Alaska, J. Geophys. Res., 112, D10208.

2-20

Pattern Formation During Ice Crystal Growth in Pure D2O Water-– ISS-KIBO Experiments –Yoshinori Furukawa 1, Etsuro Yokoyama 2, Izumi Yoshizaki 3, Shinichi Yoda 3, Tetsuo Tanaka 3,
Taro Shimaoka 4, Takehiko Sone 5, and Toshiyuki Tomobe 6
1Institute of Low Temperature Science, Hokkaido University
2
Gakushuin University, 3 JAXA, 4 JSF, 5 JAMSS, 6 IHI Aerospace
frkw@lowtem.hokudai.ac.jp

Crystal growth experiments of ice in supercooled D2O water were carried out in the Japan Experiment Module
KIBO of the International Space Station (ISS) in the period between December 2008 and March 2009.
Overview of this project and tentative results are presented.
Growth process of an ice crystal is divided in two stages. First stage is the stable-growth in which the ice crystal
grows with maintaining the shape of the thin circular disk. The growth of the edge plane of an ice disk isdominantly controlled by the thermal diffusion efficiency of the latent heat released during growth, but thegrowth of the basal planes with flat interface is controlled by the layer-by-layer kinetics. That is, two kinds ofgrowth planes with completely different growth mechanisms coexist in one crystal and its pattern formation isdominated by the interaction between both planes.
The discriminative properties observed during the ice crystal growth are completely different from the generalmechanism of dendritic growth based on such the theoretical prediction as the classical model. Understanding
the pattern formation mechanism of ice crystal will give a new perspective for studies of pattern formation andmorphological instability. For the delicate properties of the ice crystal patterns, the experiments under the
microgravity condition without any disturbance give the most ideal observations of pattern developments.
An experimental apparatus for ice growth experiment in ISS-KIBO, which was recognized as “Ice Crystal Cell”,
was developed. The apparatus was launched by the Space Shuttle flight (STS126) on 14 November 2008 (EST)and installed in the Solution Crystallization Observation Facility (SCOF) of KIBO. Experiments started on 2
December 2008 (JST) and finished on March 2009.
Dendritic pattern observed was more symmetric compared of that grown on the ground. Though the detailed
analysis obtained by space experiments is in operation at the present time, the results obtained until the present
are briefly summarized as follows: 1) 134 experiments were successfully repeated for various conditions ofsupercooling temperatures. 2) Images by two-axes interference microscopes were separately obtained and used
for the analysis of 3D-patterns of ice crystals and the thermal diffusion fields around the growing crystals. 3)
The symmetry breaking at the edge plane during morphological instability was not always observed for ice
crystals growing in space. 4) The growth rates of basal planes were qualitatively reduced for the ice crystal
growth in space.

2-21

Direct Visualization of Elementary Steps and Quasi-liquid Layers at Air-Ice
Interfaces by Advanced Optical Microscopy
Gen Sazaki 1, 2, Salvador Zepeda 1, Shunichi Nakatsubo 1, Etsuro Yokoyama 3, and Yoshinori Furukawa 1
1
Institute of Low Temperature Science, Hokkaido University
2
JST-PRESTO
3
Gakushuin University
sazaki@lowtem.hokudai.ac.jp

Growth and melting processes of ice crystals govern wide variety of phenomena on earth. Hence, this issue has
been a subject of interest for centuries. To understand crystal growth of ice at the molecular level, one has toobserve in-situ “elementary steps”, which play a key role during growth and melting processes on ice crystal
surfaces. However, since observation of ice crystal surfaces by scanning probe microscopy is very difficult, so
far only one group has succeeded in such observation by atomic force microscopy [1]. In this study, we adopted
laser confocal microscopy combined with differential interference contrast microscopy (LCM-DIM), by whichelementary steps of protein crystals (3-6 nm in height) could be visualized with sufficient contrast levels [2], andtried to visualize molecular-level surface morphologies on ice crystal surfaces.
We first attempted to observe the air-ice interface, since this interface has a much larger reflectivity thanwater-ice interfaces. By further improving LCM-DIM and growing ice crystals of higher quality, we finallysucceeded in observing ice crystal surfaces grown by the two-dimensional (2D) nucleation growth mechanism.
When steps of neighboring 2D islands coalesced with each other, the contrast of steps disappeared completely.
Such disappearances of the step contrasts were commonly observed all over the crystal surface confirming that
we succeeded in observing elementary steps (0.37 nm in height), for the first time, by optical microscopy. We
also succeeded in observing surface melting processes at air-ice interfaces. We could visualize the appearancesof two types of quasi-liquid layers (bulk-liquid like drops (BLD) and thin-liquid like layers (TLL)) and growing
elementary steps simultaneously on the same crystal surface.

References:
1) S. Zepeda, Ph.D. thesis, University of California Davis, 2004.
2) G. Sazaki, et al., J. Crystal Growth, 262, 536-542, 2004.

2-22

Antifreeze Protein Kinetics at the Ice/Solution Interface
Salvador Zepeda 1, Hiroyuki Nakaya 1, Etsuro Yokoyama 2, and Yoshinori Furukawa 1
1
Institute of Low Temperature Science, Hokkaido University
2
Gakushuin University
zepeda@lowtem.hokudai.ac.jp

Antifreeze proteins and glycoproteins help fish, plants, insects, and bacteria survive sub-freezing environments.
They inhibit the growth and recrystallization of ice while radically modifying the growth shapes. It is wellunderstood that the larger part of the effect of the proteins is a non-equilibrium phenomenon, since the melting
temperature essentially remains unchanged, while the freezing temperature is lowered about 1 degree in case of
the fish AFPs and up to 5 degrees in case of some insect AFPs. Through indirect evidence it was postulated that
the AFPs function by binding to the ice surface to alter the surface free energy, effectively lowering the freezing
temperature. The freezing temperature lowering should depend on the protein coverage and how strongly theproteins should adhere to the surface. Until recently, no measure of this coverage was available and little work
studying the proteins conformational states during the freezing and melting processes.
In our lab, we focus on learning about the fundamental mechanism of the proteins functions by studying the ice
crystal growth kinetics and protein kinetics at the ice interface as well as the proteins conformation in the solidand liquid states. We have labeled AFPI, AFPIII, and AFGPs, with fluorescent compounds and carried out
measurements during free growth and uni-directional growth from the melt.1-3 AFPIII are rigid globular proteins
and the AFPI are an α-helical rod whereas the AFGPs are a flexible extended helix with a disacharide unit every
third residue. Despite the wide range of structures and composition the proteins show nearly identical function.
We see the protein coverage saturate at about a 10 nm nearest neighbor distance on the ice surface andinterestingly this value is the same at different solution concentrations. This value is orders of magnitude greaterthan that predicted by previous models. However, at the surface only the AFPIII bind strongly enough tobecome trapped in the ice crystal matrix, whereas the AFPI and AFGP are rejected entirely rejected from thecrystal even at the slowest growth rates studied.
In supercooled solutions the AFGP becomes significantly more ordered and gradually relaxes to the solution
state conformation upon heating. This gradual loosening of the structure directly correlates with the thickeningof the quasi-liquid layer (QLL) found on the ice surface. Additionally, the thickness of the QLL increases up to
3-fold when the AFGP are present compared to pure water ice. This indicates that the proteins interaction mayvary quite dramatically even over the small temperature ranges usually studied.

References:
1. Zepeda, S.; Uda, Y.; Yokoyama, E.; Furukawa, Y.,. In Physics and Chemistry of Ice, Kuhs, W., Ed. Royal
Society of Chemistry: Cambridge, 2007.
2. Zepeda, S.; Yokoyama, E.; Uda, Y.; Katagiri, C.; Cryst. Growth Des. 2008, 8, (10), 3666-3672.
3. Uda, Y.; Zepeda, S.; Kaneko, F.; Matsuura, Y.; Furukawa, Y., J. Phys. Chem. B 2007, 111, (51), 14355-14361.

2-23

Steady-state Simulations of the Greenland Ice Sheet Using a
Three-Dimensional Full-Stokes Model
Hakime Seddik 1, Ralf Greve 1, Thomas Zwinger 2, and Olivier Gagliardini 3
1
Institute of Low Temperature Science, Hokkaido University
2
CSC – IT Center for Science Ltd.
3
Laboratory of Glaciology and Environmental Geophysics, CNRS
hakime@lowtem.hokudai.ac.jp

A three-dimensional, thermo-mechanically coupled model is applied to the Greenland ice sheet. The model
implements the full-Stokes equations for the ice dynamics, and the system is solved with the finite-element
method (FEM) using the open source multi-physics package Elmer (http://www.csc.fi/elmer/).
The finite-element mesh for the computational domain has been created using the Greenland surface andbedrock DEM data with a spatial resolution of 10 km. The study is particularly aimed at better understanding
the ice dynamics near the major Greenland ice streams. For this purpose, mesh refinement to obtain improved
computed solutions on these areas has been introduced. The meshing procedure starts with the bedrock footprint
where a mesh with triangle elements and a resolution of 5 km are employed at the vicinities of the North-East
Greenland Ice Stream (NEGIS) and the Jakobshavn (JIS), Kangerdlugssuaq (KL) and Helheim (HH) ice
streams. A size function is then applied so that the mesh resolution becomes coarser away of the ice streams up
to a maximum horizontal element size of 20 km. The final three-dimensional mesh is obtained by extruding the
2D footprint with 10 vertical layers, so that the resulting mesh contains 118944 prism elements and 69170
nodes.
The numerical solution of the Stokes and the heat transfer equations involves direct and iterative solvers
depending on the simulation case, and both methods are coupled with stabilization procedures. The boundary
conditions are such that the temperature at the surface is parameterized as a function of the latitude and thesurface elevation, the geothermal heat flux at the bedrock is prescribed as spatially constant and the lateral sides
are open boundaries.
The simulations have been conducted in order to obtain steady-state results for the velocity and temperaturefields for the entire ice sheet. The model computes the results with both bedrock sliding and melting usedalternatively so that their effects on velocities and temperature are assessed separately. The results are also
compared with a shallow-ice approximation model. The project goal is to better assess the effects of dynamicalchanges of the Greenland ice sheet on sea level rise under global-warming conditions.

2-24

Modelling Flow Dynamics and Geometry of the Austfonna Ice Cap, Svalbard
Thorben Dunse 1,2, Thomas V. Schuler 1 , Jon Ove Hagen 1, Ralf Greve 2, Geir Moholdt 1, and Trond Eiken 1
1
Department of Geosciences, University of Oslo
2
Institute of Low Temperature Science, Hokkaido University
thorben.dunse@geo.uio.no

The Austfonna ice cap covers an area of 8120 km2 and is by far the largest glacier on Svalbard. Almost 30% of
the entire area is grounded below sea-level, while the figure is as large as 57% for the known surge-type basinsin particular. Marine ice dynamics, as well as flow instabilities presumably control flow regime, form andevolution of Austfonna. During the past few decades, most drainage basins of Austfonna have experienced
retreat and thinning of the ice margins and thickening at higher elevations in the interior. There is, however,considerable uncertainty to which extent these changes are driven by surface processes (accumulation andablation) or ice dynamics (possible build up towards surge activity).
To better understand the behaviour of the ice cap, we complement ongoing glacier observations with numericalmodelling. We employ the thermodynamic, large-scale ice sheet model SICOPOLIS (http://sicopolis.greveweb.
net/) which is based on the shallow-ice approximation. We test if the observed overall flow regime of the ice cap
can be reproduced by the model.
Space-borne interferometric snapshots of Austfonna revealed a velocity structure of a slow moving polar ice cap(< 10 m/a) interrupted by distinct fast flow units with velocities in excess of 100 m/a. However, observations offlow variability are scarce. In spring 2008, we established a series of stakes along the centrelines of two
fast-flowing units. Repeated DGPS and continuous GPS measurements of the stake positions give insight in thetemporal flow variability of these units and provide constrains to the modeled surface velocity field.
Austfonna’s thermal structure is described as polythermal. However, direct measurements of the temperature
distribution is available only from one single borehole at the summit area. The vertical temperature profileshows that the bulk of the 567 m thick ice column is cold, only underlain by a thin temperate basal layer ofapproximately 20 m. To acquire a spatially extended picture of the thermal structure (and bed topography), we
used low-frequency (20 MHz) GPR profiling across the ice cap and the particular flow units. The
measurements indicate that the gross volume of Austfonna is cold. This observation is supported by model
results which suggest that regional fast flow occurs despite the lack of considerable temperate-ice volumes. Thisin turn indicates that fast flow is accomplished exclusively by basal motion in regions where the glacier base isat pressure-melting conditions, and not by enhanced deformation of considerable volumes of temperate ice.

2-25

Impact of Proglacial Lake Formation on the Retreat of Rhonegletscher,
Switzerland
Shun Tsutaki 1, 2, Daisuke Nishimura 1, 2, Takeshi Yoshizawa 1, 2, and Shin Sugiyama 1
1Institute of Low Temperature Science, Hokkaido University
2
Graduate School of Environmental Science, Hokkaido University
tsuta@lowtem.hokudai.ac.jp

After the retreat of Rhonegletscher over a bedrock ridge, a proglacial lake has been forming at the glacierforefront since 2005. The lake and the glacier draw glaciological attention because the retreat may be
accelerated by calving into the lake. To investigate the impact of the lake formation on the glacier, fieldmeasurements have been carried out at the terminal part of Rhonegletscher from 2007 to 2009. The
measurements aimed to understand the mechanism of the ice motion of Rhonegletscher and its change under
the influence of the lake water. The goal of the project is to predict the retreat of Rhonegletscher in the next
decades.
Using the technique of hot water drilling, more than 50 boreholes were drilled down to the bed and used for
subglacial and englacial measurements. Near the glacier terminus, borehole inclinometry together with surface
flow speed measurements showed that the glacier motion was principally due to subglacial flow processes, i.e.
basal sliding and subglacial sediment deformation. Borehole camera observations at glacier bed confirmed thatthe glacier was partly underlain by a 200-300 mm thick sediment layer, and the deformation this layer
dominated the glacier motion at the bed. On the other hand, sliding over bedrock was also observed in otherboreholes, suggesting that the subglacial flow processes are inhomogeneous. Therefore, the influence of the lakewater on the glacier dynamics should be examined under the consideration of basal conditions. Water levels inthe boreholes were at the level of the lake surface in the region as far as 300 m from the terminus, whichindicates the subglacial water pressure was directly controlled by the lake water. Continuous survey of stakes
installed near the terminus revealed upward ice motion immediately after the borehole water level exceeded theice flotation level. This measurement suggests that the glacier terminus is going to get afloat as a result ofthinning of the ice due to surface melting and imbalance of ice flux. The rate of ice thickness change wasdetermined as 2.8 m a-1 for the period from 2000 to 2007. This result indicates that glacier thinning has
accelerated in the 21st century, probably because of the recent warming climate and the formation of the lake.

2-26

Constituent Elements of Soluble Particles of the Dome Fuji Surface Snow and
Ice Core
Yoshinori Iizuka 1, Akira Tsuchimoto 1, Toshimitsu Sakurai 1, Motohiro Hirabayashi 2, Toshitaka Suzuki 3,
Takayuki Miyake 2, Ryu Uemura 4, Shuji Fujita 2, Hideaki Motoyama 2, Yoshiyuki Fujii 2, and Takeo Hondoh 1
1

Institute of Low Temperature Science, Hokkaido University
2
National Institute of Polar Research
3
Faculty of Science, Yamagata University
4
LSCE, CEA-CNRS, France
iizuka@lowtem.hokudai.ac.jp

The polar ice cores preserve aerosols in the past atmosphere. As concern with soluble aerosols, most studies
have been discussed ion fluxes by the melting of the ice cores using ion chromatography or continuous flow
analysis. However, the chemical compounds of the soluble aerosols being studied were unclear, due to theionization of the aerosols being caused by the melting.
We identified several soluble salts (aerosols) in Dome Fuji (DF) ice core by using Raman spectroscopy. Raman
spectroscopy helped identify soluble inclusions, and provides the chemical forms of several tens inclusions per
ice sample. However, it is difficult to compare data on solid inclusions compounds with the number density of
dust particles or ion concentrations in a statistically meaningful way. So, we have designed a sublimating systemthat operates at –50 °C, below the eutectic temperatures of major salts. This system permits us to obtain a great
many nonvolatile particles. We thereby analyzed, by using SEM-EDS, a total of more than 30,000 nonvolatile
particles taken from through surface snow (MIS1) to MIS17 ice in the DF. Our results indicate that sodium
sulfate is major soluble aerosol in the interglacial ice; sodium sulfate in the early-glacial ice; calcium sulfate andsodium chloride in the late-glacial ice. We will discuss mainly three topics for the aerosol composition at themeeting; first, post-depositional effect of sodium sulfate formation from sodium chloride and sulfuric acid in thesurface snow; second, tracing the history of major aerosol compositions during the glacial/interglacial cycles;
third, proposing sea salt origin between open sea and sea ice derived from the ratio of magnesium and sodium
chlorides.

2-27

Formation of Deuterated Formaldehyde and Methanol by Quantum Tunneling
H-D Substitution and H(D) Addition Reactions on Low Temperature Surfaces
H. Hidaka, M. Watanabe, A. Kouchi, and N. Watanabe
Institute of Low Temperature Science, Hokkaido University
hidaka@lowtem.hokudai.ac.jp
The chemical reactions on the low temperature solid surface are one of the great interests in physics andchemistry. Especially in the reactions involving light particles such as hydrogen atoms, quantum mechanicaltunneling reaction is relatively enhanced when compared to thermally activated reaction. In astrophysics, thetunneling reactions on the cold solid surfaces are key processes for the chemical evolution in cold regions ofmolecular clouds.
High-gas phase abundances of deuterated formaldehyde (formaldehyde-d) and methanol (methanol-d) havebeen observed in molecular clouds [1]. Although the cosmic abundance of deuterium is quite low (D/H~10-5)[2], deuterium enrichment in various molecules (e.g. D2CO/H2CO, CHD2OH/CH3OH) has been reported to be
several percent. This enrichment cannot be achieved by pure-gas phase chemical network model in space. The
developments of gas-grain (surface) models are still desirable, especially to account further formation
mechanisms (routes) for deuterated molecules on the grain surfaces. In this study, formation routes offormaldehyde-d and methanol-d are investigated by the D and H atoms exposure of solid H2CO and D2CO on
amorphous solid water (ASW) at 15 K, respectively.
For D + H2CO on ASW, H2CO was converted to HDCO and D2CO by the H-D substitution reactions, andCD3OD was slightly formed by the subsequent D atoms addition to D2CO. Doubly- and triply-deuterated
methanol, CH2DOD and CHD2OD, were not observed, indicating that D atoms addition to H2CO and HDCO
are much slower than the H-D substitution reactions. Thus the H-D substitution reaction in formaldehyde(H2CO → HDCO → D2CO) is dominant reaction route. For H + D2CO on ASW, the conversions of D2CO to
H2CO proceeded though HDCO, and CH3OH was produced by the H atoms addition reactions to H2CO. The
doubly-deuterated methanol, CHD2OH, which was formed by the successive hydrogenation of D2CO, wasobserved significantly. In contrast to D + H2CO, the methanol formation is efficient and is competitive to the
D-H substitution reaction. Therefore, the dominant routes are found to be D2CO → HDCO → H2CO →CH3OH and D2CO → CHD2OH. The asymmetry property in reaction routes between both reaction systems
could be understood by the potential tunneling model.
References[1]L. Loinard et al., Planet Space Sci. 50, 125 (2002).
[2]J. L. Linsky, Space Sci. Rev. 84, 285 (1998).

2-28

Antarctic Science Curriculum of Hokkaido University-– Contribution to the International Antarctic Institute -–Manabu Fukui 1, Shin Sugiyama 1, Shigeru Aoki 1, Masanobu Yamamoto 2, Takenobu Toyota 1, Takanobu
Sawagaki 2, Genta Mizuta 2, Keiichiro Ohshima 1, Yasushi Fukamachi 1, Sumito Matoba 1, Kou Shimoyama 1,
Yoshinori Iizuka 1, and Tomoko Endo 1
1
Institute of Low Temperature Science, Hokkaido University
2
Faculty of Environmental Earth Science, Hokkaido University
iai@lowtem.hokudai.ac.jp

The international Antarctic Institute (IAI) is an international program of education in cryosphere science. IAI
aims to offer international standard education programs at undergraduate and graduate level with a special
emphasis on Antarctic and cryosphere sciences. The universities and institutions share their curriculums within
the framework of IAI partnership so that the students are able to take lectures and courses internationally. As amember of this partnership, the Graduate School of Environmental Science, Hokkaido University, has launched
a new program, the Antarctic Science Curriculum. This unique program offers graduate students an opportunity
to study a broad field of polar sciences, including ocean and atmospheric processes in polar regions, ice andsnow sciences, glaciers, sea ice, permafrost, and global environmental changes. The curriculum consists ofspecial lectures given by polar scientists from IAI partner institutions, field courses held on Swiss glaciers and at
Lake Saroma, and additional lectures offered by the staff of the graduate school. Those who complete theprogram will be awarded a Diploma of Antarctic Science, independently of the master’s degrees and doctorates.
The diploma certifies that the student has acquired special knowledge and experience in polar science. Further
cooperation with IAI partners will strongly merit in enhancing understanding for cryospheric and global
environments.

2-29

Technical Supports in ILTS
Kunio Shinbori, Toru Takatsuka, Shunichi Nakatsubo, Takeshi Chigai, Kazuya Ono, Yukako Kato, Kenta
Chubachi, Kazuyuki Fujita, Masao Ishikawa, Hiroki Fukushi, Masayuki Ikeda, and Naoto Ebuchi
Institute of Low Temperature Science, Hokkaido University
naka-tech@lowtem.hokudai.ac.jp

Technical supports in various research fields by the Technical Services Section of the Institute of Low
Temperature Science, Hokkaido University, are introduced. Technical staffs in the Section support equipment
developments, field observations, laboratory experiments, data analyses, and biological and chemical analyses
in various fields covering physics, biology, chemistry, electronic engineering and information sciences. Some
members participate in expeditions to Arctic, Antarctic, and Pan-Okhotsk regions, successfully carrying out thetechnical supports. This section technically contributes to several ILTS research projects. Outstanding technicaldevelopments and contributions in recent years include developments of ice-core drills and ice-core drilling at
the Dome Fuji Station in Antarctica, developments of equipments for ice crystal growth experiments under
microgravity in the space station, operation of high-frequency ocean radar system and monitoring of the Soya
Warm Current in the Sea of Okhotsk, development of an automated platform for meteorological, oceanographic
and sea-ice observations, and building a precise clock-synchronize system using GPS on research vessels. The
Technical Services Section is composed of three shops; Equipment Development, Advanced Technical Support,
and Facility Maintenance. The Equipment Development Shop is responsible for design and production ofexperimental and observational equipments. The Advanced Technical Shop is responsible for design andproduction of electric instruments, supports of biochemical analyses and ocean modeling. The Facility
Maintenance Shop maintains the low temperature rooms and air-conditioning.

Session 3. Water and Material Cycles

3-1

Cause of the Unprecedented Freezing Disaster in January 2008 and its
Possible Association with the Global Warming
Ding Yihui, Wang Zunya, and Song Yafang
National Climate Center, China Meteorological Administration
dingyh@cma.gov.cn

Under the condition of global warming, the frequency of cold waves coming from Siberia has been decreasing
during last 50 years and China has experienced 21 significant warm winters (Dec.-Feb.) since 1986. However,in the context of warmer climate, outbreaks of very intense cold waves can be also observed and they rapidly
intruded into China, thus leading to great low temperature injury and snow /frozen rains disaster. The winters of
2004/2005 and 2007/2008 were exemplified as extreme strong and prolonged cold waves in China. The present
study has made a detailed analysis of the latter case to show whether or not the unusual cold waves could affector change the trend of global or regional warming.
The unprecedented disaster of low temperature, rain and snow and ice freezing in 2008 January in the Yangtze
River basin and South China is not local or regional event, but a part of chain events of large-scale lowtemperature and snow storms in the same period in Asia. Its severity and impacts were most significant in South
China among them, characterized by three major features: (1) co-existence of snowfall, freezing rains andrainfalls, with freezing rains being the dominant factor responsible for this disaster; (2) extreme great intensity ofabove weather phenomena, with record-breaking meteorological elements based on statistics made by China
National Climate Center and provincial Meteorological services in the Yangtze River basin and South China;(3) very long persistence of disastrous weathers, with most of them breaking historical records.
The causes responsible for this event are not single one, but cooperative and superimposed consequences ofmultiple factors. Among them, the La Nina event is its climate background, which provided the prerequisite
condition of invasion of cold airs in South China; anomalously stable atmospheric circulation features in Eurasia
is the direct cause responsible for invasions of 4 processes of cold air in South China, and the northwardtransport of warm and moist airflows coming from the Bay of Bengal and the South China Sea is the necessary
condition of formation of freezing rains and snow storms and their prolonged occurrence in the southern part ofChina.
A preliminary discussion of possible association of this disastrous event with the global warming is presented.
This event may be viewed as a short-term, regional perturbation for the global warming trend, without any
possibility of diverting the long-term trend and global pattern of the global warming.
Finally, the present paper has also made a comparison of major similarities and difference of extreme cold
events between cold and warm climates during recent 50 years, in order to gain a better insight of global
warming on extreme cold events in China.

3-2Data Integration and Analysis System for Water Cycle
Toshio Koike
The University of Tokyo
tkoike@hydra.t.u-tokyo.ac.jp

Water-related hazards usually occur as causes and consequences of large energy and water cycle fluctuations on
global and regional scales, while disasters and damages due to the hazards happen through strong linkage withhuman activities on a local scale. The observations and predictions of the water-related hazards and their
damages can be enhanced by combining global Earth observation and prediction systems and local information.
By making maximum use of the opportunities of global observations and predictions provided by the
Coordinated Energy and Water Cycle Observations Project (CEOP), this paper develops an data integration
system, CEOP-DIS, that converts global Earth observation data and prediction outputs to usable information forsound decision making in flood control on a river basin or smaller scale. CEOP provides in-situ reference site
observation data, satellite observation data, numerical weather prediction model outputs. The CEOP-DIS
consists of four components: satellite remote sensing, data assimilation, hydrological modelling and decision
making support tools. CEOP-DIS is now being developed on the GEOSS Data Integration and Analysis
System (DIAS).
Satellite-based microwave remote sensing is an effective method for collecting global information on land
surface hydrology. Soil moisture, water content in vegetation, snow and permafrost can be monitored effectively
by the passive microwave sensors. In addition, they are effectively combined with visible-infrared sensor datafor getting integrated products. The CEOP reference site data sets can improve the algorithms as well as validate
the accuracy of the product.
A land data assimilation system was developed at the University of Tokyo (LDAS-UT) by employing Simple
Biosphere Model (SiB2) as the dynamic model to calculate surface fluxes and soil moisture, a radiative transfer
model (RTM) as the observation operator to estimate microwave brightness temperature, and several
optimization schemes. The passive microwave remote sensing data observed by the Advanced Microwave
Scanning Radiometer for the Earth Observing System (AMSR-E) and the model located time series (MOLTS)
archived CEOP are used for applying the LDAS-UT. The assimilated results are validated by the CEOP
reference site data. A satellite-based cloud microphysics data assimilation system (CIMDAS) was developed bycoupling a cloud microphysics scheme embedded in the advanced regional prediction system (ARPS), a
physically based land-atmosphere coupled radiative transfer model, and several optimization schemes.
CIMDAS was applied to the National Centers for Environmental Prediction global forecast system reanalysis
data and AMSR-E archived in CEOP, for downscaling from a global scale to a meso-scale area by introducing
more accurate initial condition.
CEOP-DIS includes an integrated distributed hydrological model, WEB-DHM, which couples a realistic land
surface model, the widely used SiB2, with a geomorphology-based hydrological model. The results ofapplication of the WEB-DHM to the Little Washita river basin in USA and the upper Tone river basin of Japan,
using the digital elevation model show good performance in simulating floods, including those after periods oflow water flow, soil moisture, surface temperature and fluxes. This means the WEB-DHM can provide
reasonable initial conditions by itself for the flood prediction after long-term low water flow. Challenges onapplication of WEB-DHM to cold regions are now on-going.

3-3Kosa (Asian Dust) Particles and Atmospheric Constituents on Particle Surface
Yasunobu Iwasaka
Frontier Science Organization, Kanazawa University
kosa@t.kanazawa-u.ac.jp

Kosa particles have been recognized as an important constituent characterizing air quality in North-East Asia.
The particles are transported long-range by westerly and various atmospheric constituents make interesting
reactions on the particle surface during the long-range transport of KOSA. Anthropogenic constituents emitted
from the coast areas of China land frequently deposit on the particle surface and react with particle materials.
Balloon-borne and aircraft borne measurements strongly suggested that sulfur dioxide gas reacts with KOSA
materials and sulfate were produced on the surface (Figure). Air masses from the arid region meet not only
polluted air but also the air with high humidity, and atmospheric water seems to be important factor activating
the surface reactions.
More recently KOSA has been suggested as carrier of not only pollutants but also micro-organisms, andmixture of KOSA and micro-organisms attracts great concern from view point of cloud physics since thoseparticles can act as extremely active ice nuclei. East China Sea and Japan Sea have been known as strong
sources of water vapor and the high humidity possibly affect KOSA surface reactions, activities of micro-biota
on particle surface during KOSA particle long-range transport. Therefore it can be said that long-range transportof KOSA particles strongly link with water cycle of north-east Asia.

Relative Weight Ratio of Al, S and Ca

3-4

Isotopomer Studies to Trace Water and Material Cycles Featuring Some
Extreme Environments
Naohiro Yoshida
Dept. of Environmental Science and Technology, also Dept. of Environmental Chemistry and Engineering, andGlobal COE Research Center for the Evolving Earth and Planets, Tokyo Institute of Technology
yoshida.n.aa@m.titech.ac.jp

The Earth’s environment when the life was born was a severest one without oxygen and ozone which protects
life from UV flux. The life evolved and modified the Earth’s environment more habitable. Material cycle on the
Earth’s surface has been modified from the abiotic to biotic domination. There have been several severe eventsin a global scale and life survived. I have worked on material cycle analysis from the early Earth to the present
day global change to better understand the relationship between the Earth’s environment and the life. Some
examples of these will be discussed featuring the background of isotopomers (isotope containing molecules)
and their applications for material cycles in the fields from the earth and planetary, environment, to biologicalmetabolisms.
Methanogenic microbes may be one of the most primitive organisms, though it is uncertain when methanogens
first appeared on Earth. During the Archaean, methanogens may have played an important role in regulatingclimate, because they could have provided sufficient amount of greenhouse gas, CH4 for avoiding a severely
frozen condition due to the lower solar luminosity and methane has been important in controlling both thesurface temperature and atmospheric chemistry of the Earth. Nevertheless, no direct geological evidence has
been available in favor of the existence of methanogens in the Archaean period, except for circumstantial
evidence from the ~2.8-Gyr-old 13C-depleted kerogen. We (Ueno et al., 2006) have performed crushingextraction and carbon isotope analysis of CH4-bearing fluid inclusions in ~3.5-Gyr-old hydrothermal
precipitates from Pilbara Craton, Australia. The results indicate that the extracted fluids contain microbial CH4
with carbon isotopic compositions of less than –56‰ that was entrapped in original precipitates. This provides
the oldest evidence of methanogen (>3.46 Gyr ago), which predates previous geochemical evidence byapproximately 700 million years.
Photolysis of SO2 is believed to be responsible for Mass Independent Fractionation (MIF) of sulfur isotopes
observed in stratospheric aerosol and in minerals deposited before 2.3 billion years ago. In order to simulate thephotochemical MIF, we (Danielache et al., 2008) obtained high-resolution UV absorption spectra of
isotopomers of SO2 (32SO2, 33SO2 and 34SO2) and calculated wavelength dependence of 34S/32S and 33S/32S
fractionation factors. The fractionation factors both for d34S and D33S are very sensitive to wavelength, which
implies that single line photolysis by artificial laser UV causes MIF, but should not be directly applied toatmospheric environment, in which solar irradiation has broad UV spectrum. We then calculated MIF effectresulted from solar UV as a function of overhead column densities of O2, O3, CO2, H2O and SO2 itself. SO2
dissociation by solar irradiation causes significant MIF. Assuming 190-220 nm photolysis of SO2 is responsible
for the MIF, our calculation also suggests that aerosol sulfate may have positive D33S anomaly under O2-free
condition even if including self-shielding effect. This is inconsistent with the inferred negative D33S of Archeansulfate aerosol. The Archean MIF reaction pathways should have been more related to the atmosphericchemistry (Ueno et al., 2009). This finding is also applicable to the present day MIF and its implications for thepresent atmospheric chemistry.

References:
Danielache, S. O., C. Eskebjerg, M. S. Johnson, Y. Ueno, and N. Yoshida (2008), High-precision spectroscopyof 32S, 33S, and 34S sulfur dioxide: Ultraviolet absorption cross sections and isotope effects, J. Geophys.
Res., 113, D17314, doi:10.1029/2007JD009695.
Ueno, Y., K. Yamada, N. Yoshida, S. Maruyama, and Y. Isozaki (2006), Evidence from fluid inclusions for
microbial methanogenesis in the early Archaean era, Nature, 440, 516-519.
Ueno, Y., M. S. Johnson, S. O. Danielache, C. Eskebjerg, A. Pandey, N. Yoshida (2009), Geological sulfur
isotopes indicate elevated OCS in the Archean atmosphere, solving faint young sun paradox, Proceedingsof the National Academy of Science, doi:10.1073:pnas.0903518106.

3-5

Why Cloud Science?
Yasushi Fujiyoshi
Institute of Low Temperature Science, Hokkaido University
fujiyo@lowtem.hokudai.ac.jp

Clouds are the most familiar aspect of our atmospheric environment. Followings are the manifest of the Cloud
Appreciation Society (http://www.cloudappreciationsociety.org/, my membership number is 9042).
@We believe that clouds are unjustly maligned and that life would be immeasurably poorer without them.
@We think that they are Nature’s poetry, and the most egalitarian of her displays, since everyone can have afantastic view of them.
@We pledge to fight ‘blue-sky thinking’ wherever we find it. Life would be dull if we had to look up atcloudless monotony day after day.
@We seek to remind people that clouds are expressions of the atmosphere’s moods, and can be read likethose of a person’s countenance.
@Clouds are so commonplace that their beauty is often overlooked. They are for dreamers and theircontemplation benefits the soul. Indeed, all who consider the shapes they see in them will save on
psychoanalysis bills.
And so we say to all who’ll listen: Look up, marvel at the ephemeral beauty, and live life with your head in theclouds!
Clouds play a significant role in determining the radiation budget of the earth and serve as an important link in
the water and material cycles. The role of clouds is very large in the high latitude or polar region. In theprediction of surface temperature due to increased carbon dioxide using climate models, a temperature variationof two or three times the average of the entire earth has been predicted in the polar region. What kinds of clouds
they are, how high they are distributed, and how much snowfall they bring are big questions for growth anddecay of sea ice. Impacts of diamond dust on radiation and water budgets at polar regions are also significant.
Aerosol direct effect can be evaluated by knowing the increase of optical thickness of man-made aerosols.
Conversely for indirect effect, phenomenon itself is not well known because the modification mechanism ofclouds is very complicated. The role of clouds can switch from heating to cooling, depending on the altitude ofclouds, how many layers the clouds have, and vertical distribution of detailed physical quantity, such as cloudparticle distribution, and difference between water and ice.
The aerosol-cloud interaction is not enough to evaluate aerosol indirect effect. Vertical and horizontal air-motion,that is, the wind is the key factor that connects water and material cycles. Water vapour evaporated from groundand sea surfaces is carried away by the wind, condenses to form clouds at various altitudes, and returns to theearth's surface as rain or snow. The speed of water cycle in the atmosphere depends on the ratio between theamount of cloud water (liquid and ice) and that of rain or snow, and on the rate at which cloud particles change
into rain or snow in clouds. Understanding temporal change of three dimensional structure of wind fields is anextremely important subject to study transportation and mixing of many materials (e.g., water vapour, aerosols,
gaseous components, insects, bacteria etc.).
Therefore, Cloud Science whose research topics cover the interactions between air-sea, -land surface, -snow/ice,-topography, -ecosystem, and -culture is indispensable to study water and material cycles.

Session 4. Pan Okhotsk Researches

4-1

Decadal Variability in the North Pacific Subpolar Gyre Circulations
Bo QiuSchool of Ocean & Earth Science & Technology, University of Hawaii at Manoa
bo@soest.hawaii.edu

Large-scale ocean circulation changes in the subpolar gyre of the North Pacific Ocean are investigated using
satellite altimetry data of the past 17 years. Our particular interests are on the three broad-scale current systems:
the North Pacific Current (NPC), the Alaska Gyre, and the Western Subarctic Gyre (WSG). To facilitate theunderstanding of the observed changes, we adopted a two-layer ocean model that includes first-mode baroclinic
Rossby wave dynamics and time-dependent barotropic Sverdrup dynamics. The NPC intensified steadily overthe period of 1992 to 1999 and its strength modulated on the interanual timescales in the recent decade. Much ofthis intensification/modulation is due to the SSH fluctuations on the northern side of the NPC. Similar SSH
changes are also found in the interior of the Alaska Gyre. Both of these SSH changes are shown to be the resultof surface wind stress curl forcing related to the Pacific decadal oscillations (PDOs) and accumulated along thebaroclinic Rossby wave characteristics initiated from the eastern boundary. The WSG changed interannuallyfrom a zonally elongated gyre in 1993-1995 to a zonally more contracted gyre in 1997-1999. It remained in thelatter, weakened state over the past 10 years. The structural change of the WSG is due to the decadal SSH
anomalies within the WSG as a result of the baroclinic Rossby wave adjustment attenuated by eddy dissipation.
Along the western boundary of the subpolar North Pacific, variability of the East Kamchatka Current (EKC)
and Oyashio is in balance with that of the interior Sverdrup flow on the annual and year-to-year time scales. On
the decadal time scales, the EKC/Oyashio variability is determined by the baroclinic incoming SSH signals.

4-250-year Records of Climate Changes in Ice-cores from Kamchatka and Alaska
Sumito Matoba
Institute of Low Temperature Science, Hokkaido University
matoba@lowtem.hokudai.ac.jp

Ice-core from polar glaciers and ice sheets is one of the most important archives of paleo-environmental
information. Ice-core drillings were started in 1960s at the ice-sheet in Greenland and Antarctic. The ice-corestudies contributed innovated knowledge to clarification of paleo-environmental variations in Quaternary, suchas Dansgaard-Oeschger Cycle, increase of greenhouse gases concentrations, and so on (e.g. Dansgaard et al,1993). Ice-core studies from mountain glacier were started in 1970s. Thompson and others carried out
glaciological expedition and ice-core drilling at Qelkaya glacier in Peru, and demonstrated the fact that toreconstruct obvious paleo-climate record from the mountain glacier in tropical region (Thompson et al, 1984).
We have obtained several ice-cores from Kamchatka and Alaska, where is the most backward region in theworld in terms of ice-core studies in mid and low latitude, since 1998 (e.g. Shiraiwa et al., 2004; Matoba et al.,2006). Our analyses of the ice-core from the summit of Mount Ichinsky (55.6°N, 157.7°, 3600 m a.s.l) in
Kamchatka indicate the following. 1) Neither dD profile nor stratigraphy of the ice-core indicates signals ofsignificant global warming. 2) The increase of percentages of ice layer from 1950s to 1960s reflects the increaseof the amount of solar radiation in summer time since increase of air temperature was not observed at any
meteorological stations in Kamchatka. 3) We assume that the remarkable negative peaks of δD from 1960s to
1970s were formed by not only low temperature in winter but also by changes of moisture source caused byexpansion of sea ice area at the Sea of Okhotsk in winter. From this point of view, high frequency of
appearances of negative peak of δD from 1960s to 1970s shows production of sea ice was relative higher. In
Alaskan side, δD profile in ice-core from the summit of Mount Wrangell (62°N, 144°W, 4000m a.s.l.) did notshow a signal of significant global warming. On the other hand, bore-hole temperature profile of Aurora Peakglacier (63.5°N, 146.5°W, 3070m a.s.l.) indicates recent warming.
References:
Dansgaard, W., Johnsen, S.J., Clausen, H.B., Dahl-Jensen, D., Gundestrup, N.S., Hammer, C.U., Hvidberg,
C.S., Steffensen, P.S., Sveinbjornsdottir, A.E., Jouzel, J. and Bond, G. (1993) Evidence for generalinstability of past climate from a 250-kyr ice-core record, Nature, 364(6434), 218-220.
Matoba, S., S. V. Ushakov, K. Shimbori, H. Sasaki, T. Yamasaki, A. A. Ovshannikov, A. G. Manevich, T. M.
Zhideleeva, S. Kutuzov, Y. D. Muravyev, and T. Shiraiwa. 2007. The glaciological expedition to Mount
Ichinsky, Kamchatka, Russaia. Bulletin of Glaciological Research, 24, 79-85.
Shiraiwa, T., Kanamori, S., Benson, C.S., Solie, D. and Muravyev, Y.D. (2004) Shallow ice-core drilling at
Mount Wrangell, Alaska, Bulletin of Glaciological Reaserch, 21, 71-77.
Thompson, L.G., Mosley-Thompson, E., Arnao, B. M. (1984) El Nino-Southern Oscillation events recorded in
the stratigraphy of the Tropical Quelccaya Ice Cap, Peru, Science, 226, 4670, 50-53.

4-3

Large Changes in Seasonal Sea Ice, Sea Surface Temperature andProductivity in the Sea of Okhotsk during the Last Deglaciation
Osamu Seki
Institute of Low Temperature Sciences, Hokkaido University
seki@pop.lowtem.hokudai.ac.jp

Changes in the senvironment of the central Sea of Okhotsk were reconstructed using multiple biomarkers inorder to investigate paleoenvironmental changes during the glacial-interglacial cycles. The alkenones, CaCO3,
and biogenic opal records indicate that the dominant phytoplankton species during deglaciation was the
coccolithophorid, which was replaced by diatoms in the late Holocene. The TEX86 temperature records reveal~3 ºC lower summer SST during glacial maxima than during interglacial periods and significant warming
during the deglaciations (15-10 ka and 136-130 ka). This is consistent with previous inferences of more
expanded and persistent seasonal sea ice during the glacial periods than the present day and its substantial retreat
during the deglaciation. Timing of the deglacial warming also coincided with a distinct increase incoccolithophorid productivity indicated by CaCO3 and alkenone records, suggesting a causal relationshipbetween sea surface warming and coccolithophorid blooms during the deglaciations. As for terrestrial
paleoclimate, hydrogen isotopic compositions of n-alkanes in peat core taken from the northeast China indicatethat lake water levels reached their maxima during the deglacial period, suggesting high effective precipitationin Amu River basin. The relationship could reflect an increase in the supply of fresh and warm water from theAmur River during deglaciation, which significantly impacted hydrology by facilitating sea surface stratification,
which in turn promoted production of coccolithophids. The last deglaciation is also characterized by remarkableincreases in terrestrial organic matter input. This finding was interpreted by the outflow of terrestrial organic
matter from the submerged land shelf to the Sea of Okhotsk through the East Sakhalin Current.

4-4Modeling the Pan-Okhotsk Region
Tomohiro Nakamura
Institute of Low Temperature Science, Hokkaido University
nakamura@lowtem.hokudai.ac.jp

The Okhotsk Sea and the surrounding area are called as the Pan-Okhotsk region. This area affects the climate inJapan through the formation of the Okhotsk high in summer and the Siberian high in winter, for example.
Further, outbreaks of cold air from the Siberian High cause a large amount of sea ice production in the Okhotsk
Sea. During the ice formation, the rejection of salt from seawater and cooling by cold air produce dense water,which subsequently spreads in the intermediate layer of the Okhotsk Sea and the North Pacific Ocean. Thisdense water formation, together with tidal mixing in the Kuril Straits, induces significant heat and freshwater
fluxes and carries various gases, such as greenhouse-effect gases, from the atmosphere to the oceanicintermediate layer, thus affecting the climate formation and variability. The spreading of the dense water also
involves the transport of nutrients, particularly iron supplied from the Amur River. This results in highprimary-production (associated with oceanic phytoplankton) in the Pan-Okhotsk region, thus making the carbon
cycle active in addition to fishery.
These processes are varying in various time-scales, associated with the Pacific Decadal Oscillation (PDO), an
18.6-year variation in tidal mixing, the Arctic Oscillation (AO), and so on. The Pan-Okhotsk region is also
sensitive to the global warming, which is causing warming in Siberia, decrease in sea ice production, andwarming of the oceanic intermediate layer. These changes are suggested to result in changes in iron and nutrient
supplies and thus in primary production, as well as in the oceanic and atmospheric circulation. For a much
longer time-scale, glacial-interglacial cycles affect the role of the Pan-Okhotsk region in the climate through thechanges in ice production and sea surface salinity.
Our attempts to modeling such climate formation and variability in the Pan-Okhotsk region, which is being
conducted at the Pan-Okhotsk Research Center, shall be presented.

Session 5. Frontier Ice and Snow Science5-1

Letters from the Sky:
Nakaya, Sapporo and the Broad Scientific Reach of the Physics of Ice
John S. Wettlaufer
A.M. Bateman Professor of Geophysics and Physics
Professor of Applied Mathematics
Yale University
john.wettlaufer@yale.edu

Nakaya was trained as a nuclear physicist and turned his keen intuition and skills toward the many facets of thebeauty and mysteries of snow and ice. He eventually sought to understand many of these phenomena toilluminate aspects of meteorology and yet we now know that the surface of ice exhibits the swath ofphase-transition phenomena common to all materials and as such it acts as an ideal test bed of both theory andexperiment. It is readily available, transparent, optically birefringent, and probing it in the laboratory does not
require cryogenics or ultrahigh vacuum apparatus. Systematic study reveals the range of critical phenomena,equilibrium and nonequilibrium phase-transitions, and, most relevant to this review, premelting, that are
traditionally studied in more simply bound solids. While this makes investigation of ice as a material appealingfrom the perspective of the physicist, its ubiquity and importance in the natural environment also make icecompelling to a broad range of disciplines in the Earth and planetary sciences. In this talk I describe many
aspects of physics of ice and their relationship with the behavior of other materials more familiar to thecondensed-matter community. I then discuss the many tendrils of the basic phenomena as they play out on land,in the oceans, and throughout the atmosphere and biosphere.

5-2

Metamorphism of Stratified Firn at Dome Fuji, Antarctica: A mechanism for
local Insolation Modulation of Gas Transport Conditions during Bubble
Close-offShuji Fujita 1, Junichi Okuyama 2, 3, Akira Hori 2, 4, and Takeo Hondoh 2
1
National Institute of Polar Research, Research Organization of Information and Systems
2
Institute of Low Temperature Science, Hokkaido University
3
Advanced Applied Science Department, Research Laboratory, IHI Co., Ltd.
4
Department of Civil Engineering, Kitami Institute of Technology
sfujita@nipr.ac.jp

The evolution of the structure of a 112.59-m-long firn core recovered at Dome Fuji, East Antarctica, wasinvestigated in order to improve understanding of firn densification and bubble formation processes, which areimportant for interpreting local insolation proxies used for astronomical dating of deep ice cores. Using selected
samples, we measured physical properties including: (i) the relative dielectric permittivities in both the verticaland horizontal planes, (ii) the bulk density at a resolution of millimeters, (iii) the three-dimensional geometricstructure of pore space, and (iv) crystal orientation fabrics. We found that the firn at Dome Fuji contains
horizontal strata with thicknesses of several centimeters. Near the surface of the ice sheet, these strata arecharacterized by contrasting bulk density. Earlier field studies suggest that summer insolation causes
densification of surface firn. Down to ~30 m, density maxima exhibited a clear positive correlation with thestrength of structural anisotropy and c-axis clustering around the vertical. In contrast, the correlation is negativein deeper firn, confirming previous findings that initially less-dense firn became denser than initially dense firn.
In addition, numerous examples of textures indicating that deformation preferentially occurred in weaker layers
were found. Moreover, the initially dense firn layers were more permeable for air near the bottom of firn. We
propose a model linking firn properties with conditions for the gas transport processes near the bottom of firn.
The model explains how stronger insolation can lead to bulk ice with a lower O2/N2 ratio and smaller total gas
content.

5-3

Dynamic/Thermodynamic Modelling of Ice Sheets in Changing Climates
Ralf Greve
Institute of Low Temperature Science, Hokkaido University
greve@lowtem.hokudai.ac.jp

An ice sheet is a land-based ice body with an area greater than 50,000 km2. The only current ice sheets on Earthare in Antarctica and Greenland; during the last glacial period at the Last Glacial Maximum (LGM) the
Laurentide Ice Sheet covered much of Canada and North America, the Fennoscandian Ice Sheet covered
northern Europe and the Patagonian Ice Sheet covered southern South America. Ice sheets featuregravity-driven free surface flow (“glacial flow”), controlled by internal stresses, temperature and basal friction(e.g., Greve and Blatter 2009).
Since the late 1970s, numerical modelling has become established as an important technique for theunderstanding of ice sheet dynamics. Ice sheet models are particularly relevant for predicting the possible
response of ice sheets to climate change, and thus a number of such models have been developed over the years.
SICOPOLIS (SImulation COde for POLythermal Ice Sheets; http://sicopolis.greveweb.net/) is an establishedmodel currently operated at the Institute of Low Temperature Science. It is based on the widely-used shallow ice
approximation, so that longitudinal stress gradients are neglected. Its particularity is the physically adequate
implementation of basal layers of temperate ice (regions with a temperature at the pressure melting point).
Recent observations suggest that ice dynamics could play a crucial role in predicting the contribution of ice
sheets to future sea level rise under global warming conditions. The need for further research into the matter waseven explicitly stated in the Fourth Assessment Report (AR4) of the United Nations Intergovernmental Panel on
Climate Change (IPCC): “Dynamical processes related to ice flow not included in current models but suggested
by recent observations could increase the vulnerability of the ice sheets to warming, increasing future sea levelrise. Understanding of these processes is limited and there is no consensus on their magnitude.” (IPCC 2007).
In this talk, the state of the art and current problems of ice sheet modelling will be reviewed. The ice sheet model
SICOPOLIS will be introduced briefly, and exemplary applications of SICOPOLIS to the past glaciation ofGreenland and Antarctica over climatic cycles as well as future global warming scenarios will be presented.

References:
Greve, R. and H. Blatter. 2009. Dynamics of Ice Sheets and Glaciers. Springer. ISBN 978-3-642-03414-5.
IPCC, 2007. Summary for Policymakers. In: Solomon, S., and 7 others (eds.), Climate Change 2007: The
Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of theIntergovernmental Panel on Climate Change, pp. 1–18. Cambridge University Press, Cambridge, United
Kingdom and New York, NY, USA. URL: http://ipcc-wg1.ucar.edu/wg1/wg1-report.html.

5-4

Ice Surface Reactions: Its Role in Chemical Evolution in Space
Naoki Watanabe
Institute of Low Temperature Science, Hokkaido University
watanabe@lowtem.hokudai.ac.jp

Among the many kinds of interstellar molecules observed, the abundances of some major species such as H2,
H2O, and organic molecules can not be explained by gas-phase synthesis; therefore, surface reactions on cosmic
ice dust are considered for the synthesis of such molecules. In an interstellar molecular cloud where thetemperature is as low as 10 K and the radiation field is very weak, the energetic processes in/on ice dust isinefficient and thus tunneling surface reactions involving hydrogen atom become important for chemical
evolution. We report the experiments on reactions of hydrogen atoms with O2 and CO on the ice dust analogue,
namely amorphous solid water (ASW), at very low temperatures.
Below 20 K, successive addition of hydrogen atoms to CO and O2 efficiently produces H2CO, CH3OH, andH2O2, H2O, respectively. At such low temperatures, some of hydrogen additions such as H + CO → HCO
proceed via tunneling reactions rather than thermally-activated reactions. Effective reaction rates and isotope
effect of the tunneling reactions to produce HCO and H2O were measured. The surface of ASW was found toenhance the effective rate of hydrogen addition to CO at relatively higher temperatures, namely 15-20 K. Our
experiments first demonstrated that the interstellar molecules abundantly observed in ice dust, H2O, H2CO, andCH3OH, are efficiently produced via the tunneling H-atom addition reactions in the interstellar environments. A
series of our experiments was summarized in Progress in Surface Science 83 (2008) 439.

5-5

Direct Visualization of Elementary Steps and Quasi-liquid Layers at Air-ice
Interfaces by Advanced Optical Microscopy
Gen Sazaki 1, 2, Salvador Zepeda 1, Shunichi Nakatsubo 1, Etsuro Yokoyama 3, and Yoshinori Furukawa 1
1
Institute of Low Temperature Science, Hokkaido University
2
JST-PRESTO
3
Computer Center, Gakushuin University
sazaki@lowtem.hokudai.ac.jp

Growth and melting processes of ice crystals govern wide variety of phenomena on the earth. Hence this issue
has been a subject of interest for centuries. To understand crystal growth of ice at the molecular level, one has toobserve in-situ “elementary steps”, which play a key role during growth and melting processes, on ice crystal
surfaces. However, since observation of ice crystal surfaces by scanning probe microscopy is very difficult, so
far only one group succeeded in such observation by atomic force microscopy [1]. In this study, hence weadopted laser confocal microscopy combined with differential interference contrast microscopy (LCM-DIM),
by which elementary steps of protein crystals (3-6 nm in height) could be visualized with sufficient contrast
levels [2], and tried to visualize molecular-level surface morphologies on ice crystal surfaces.
We tried to observe air-ice interfaces, since this interface has much larger reflectivity than water-ice interfaces.
By further improving LCM-DIM and growing ice crystals of higher quality, we finally succeeded in observing
ice crystal surfaces grown by the two-dimensional (2D) nucleation growth mechanism. When steps ofneighboring 2D islands coalesced each other, the contrast of steps disappeared completely. Such disappearancesof the step contrasts were commonly observed all over the crystal surface. Hence we concluded that we
succeeded in observing elementary steps (0.37 nm in height), for the first time, by optical microscopy. We also
succeeded in observing surface melting processes at air-ice interfaces. We could visualize the appearances of
two types of quasi-liquid layers (bulk-liquid like drops (BLD) and thin-liquid like layers (TLL)) and growing
elementary steps simultaneously on the same crystal surface.

References:
1) S. Zepeda, Ph.D. thesis, University of California Davis, 2004.
2) G. Sazaki, et al., J. Crystal Growth, 262, 536-542, 2004.

Secretariat of the ILTS International Symposium"Frontier of Low Temperature Science"
Naoto Ebuchi, ILST Hokkaido University
Yasushi Fujiyoshi,, ILST Hokkaido University
Yoshinori Furukawa, ILST Hokkaido University
Jun Nishioka , ILST Hokkaido University
Ayumi Tanaka, ILST Hokkaido University
symposium@lowtem.hokudai.ac.jp
http://www.lowtem.hokudai.ac.jp