In the Daisetsu Mountains, Hokkaido, northern Japan, surface energy balance observations have started during the summer 2008, aiming at physically-based understanding of mosaic-like distribution of permafrost (T. Maeda, G. Iwahana, M. Ishikawa, H. Arai and N. Matsuoka).
The automatic weather systems provide concurrent data on radiation components, air temperature, rainfall, humidity and wind components (by sonic anemometer-thermometer) at permafrost and immediately adjacent topermafrost-free sites. Stable isotope analysis was also introduced to evaluate the origin of surface water on summit areas underlain by permafrost (H. Arai, M. Ishikawa, A. Sugimoto, G. Iwahana and T. Maeda). Water was sampled from seasonally and permanently frozen ground, rainfalls, snowmelts and small tributaries.
In the northern Japanese Alps, rockfall activity and supranival debris sliding were investigated (Y. Kariya, Y. Matsunaga, Y. Miyazawa, J. Komori, M. Ishii, G. Sato, K. Tomita and S. Iwata). During the ablation period in 2007, the position, size and lithology of all fallen debris on perennial snow patches in the valley floor were measured every month, and these data were used to estimate the mode and rate of debris production. Supranival block sliding was monitored with an automatic camera. Snow ablation and bedrock thermal regimes were also monitored. In the alpine and subalpine zones of the northern Japanese Alps, geology and geomorphology of landslides were studied (Y. Kariya, G. Sato, J. Komori and K. Tomita). Sedimentological and Quaternary chronological information was newly obtained from the Mt. Shiroumadake and Mt. Chogatake areas. Collected data show that non-sorted chaotic sediments, which have previously been considered to be a glacial origin, are more likely to have originated from a large landslide and/or a debris avalanche.
Intensive field campaigns have been undertaken in the southern Japanese Alps from 2007 to 2008. One group, composed of scientists from Meiji University and other institutions (T. Koyama, A. Amaizawa, N. Takahashi, S. Sawaguchi, M. Aoyama and Y. Sugawara), studied periglacial geomorphology of the Mt. Akaishi-dake area during the summers of 2007 and 2008. Th e topics include mapping of patterned ground, structural analysis and thermal monitoring of solifl uction lobes, as well as thermal and chronological characteristics of rock glaciers. Another group (R. Nishii, N. Matsuoka and A. Ikeda, University of Tsukuba) continued monitoring of rock and soil slope dynamics in the Mt. Ainodake area. Newly introduced techniques are visual recording of stone movement with an automatic camera and diff erential GPS for monitoring annual movement of rock glaciers. Detailed monitoring of rock creep and sliding has also been undertaken on the top of a rockslide by both automatic and periodical manual observations. The data show seasonal variation in rock movement associated mainly with thawing of snow and seasonal frost, as well as with large rainfalls in summer.
A synthetic study on the permafrost of the Fuji volcano, the highest peak in Japan (3776 m asl), was started by postdocs (A. Ikeda, G.. Iwahana, K. Fukui, T. Sueyoshi and Y. Sawada) with the help of senior researchers (T. Tamura, K. Harada and K. Saito), a visiting researcher (A. Kellerer-Pirklbauer) and graduate students (T. Watanabe and R. Nishii). In 2008, a 3-m deep borehole and a 2-m automatic weather station were constructed on the summit area. A monitoring network of shallow ground temperature was also set on the north- and south-facing slopes. In addition, hydrological conditions in the pyroclastic rock and lava were examined by applied geophysical methods to estimate permafrost distribution. The project is planned to be enlarged and continued for long-term monitoring of the environmental changes and studying interaction between permafrost and volcanic activity.
Several overseas projects are also on going. Model experimental sites established in Svalbard have provided data on thermal contraction cracking in ice- and soil-wedge polygons, rock weathering and movement of a polar rock glacier, as well as their controlling parameters, with a variety of methods (N. Matsuoka). The project is a collaboration with UNIS (H.H. Christiansen) and University of Oslo (O. Humlum) as part of the IPA periglacial group activity aiming at standardizing monitoring techniques and extending the monitoring network. Detailed geophysical sounding was applied to detect subsurface frost wedge structures under non-sorted polygons with a wide range of diameter and composed of diff erent materials at two locations in Svalbard (T. Watanabe). In August 2008, an educational project related to IPY Project No. 50 (TSP) was conducted in Svalbard, as a part of ‘International University Course on High Arctic Permafrost Landscape Dynamics in Svalbard and Greenland’. Three Japanese graduate students attended the lectures, fi eldwork and laboratory analysis in UNIS, Adventdalen and Kapp Linne, guided by H.H. Christiansen, B. Elberling (Univ. Copenhagen) and N. Matsuoka.
In Alaska, the project ‘2004 Forest Fire Impacts to Hydrological Cycles, Permafrost and Eco Systems in Central Alaska’ has continued since 2005 in order to monitor permafrost conditions after severe wildfire (K. Harada and K. Saito). In August 2008, observations including manual measurements of thaw depth were carried out at the Kougarok site near Nome. Measurements of surface roughness were also conducted to compare with the satellite data. Since 2007 ground temperatures have been monitored with data loggers to obtain continuous data of thaw depth and ground temperature and to understand the effect of the wildfire on the permafrost condition and vegetation recovery. The study area of rock glacier research in Alaska by A. Ikeda was shifted from the Brooks Range in the Arctic to the Alaska Range in the central Alaska after the NICOP. The focus of the study was also changed from distribution characteristics of rock glaciers to the direct monitoring of processes related to debris and ice accumulation on rock glaciers.
Long-term monitoring campaigns still continue in the Swiss Alps. The monitoring focused on frost weathering, heave, creep, solifluction and permafrost creep (N. Matsuoka and A. Ikeda). Differential GPS was newly introduced to monitor annual movement of rock glaciers and solifl uction lobes. K. Fukui, National Institute of Polar Research (NIPR) undertook a permafrost research expedition in the South Chuyskiy Range, Russia Altai Mountains, in the summer of 2008. The expedition is joint research between NIPR and Altai State University (Prof. Mikhailov, Dr. Ostanin and Dr. Troshkin). They installed ground temperature sensors in ice wedge polygons in the Akkol Valley, and found a large pingo originated from the Little Ice Age moraine in the Tardura Valley (2100 m a.s.l.) and many rock glaciers in the Yelanzash Valley (2400 m a.s.l.).
Finally, ISOP (Informal Seminar on Permafrost) hosted meetings several times in Sapporo at the Hokkaido University, aiming at exchanging information on permafrost monitoring and planning joint fi eld campaigns.
Norikazu Matsuoka (firstname.lastname@example.org)