We Are Tomodachi Spring / Summer 2017

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11AchievementYearNotesDiscovery of meteorites in Antarctica1969–About 17,000 meteorites have been found, including precious meteorites of Martian and lunar origin. This has contributed both to the elucidation of the meteorite concentration mechanism, which is closely related to the flow of ice sheets and position of mountain ranges, and to the discovery of large numbers of meteorites by research expeditions from other countries. Aurora research1970–An aurora observation rocket test facility was set up at Syowa Station, and over about 20 years starting in 1970 a total of 58 rockets were launched into the middle and upper atmosphere where the aurora appears. This contributed to studies of the physical properties of the aurora and understanding of the mechanism by which it occurs.Discovery of ozone hole1982First discovery of an area over Antarctica where the volume of ozone was extremely low. This led to initiatives to protect the ozone layer, including adoption of the Vienna Convention in 1985 and the Montreal Protocol in1989. Discovery of moss pillars1995–“Moss pillars,” which are aggregates of mosses and algae, were discovered on a lake bottom near Syowa Station in 1995. Learning the structure and function of moss pillar ecosystems may be useful in understanding the stability and restorability of the earth’s ecosystem overall, including humans.Ice core research1996–In 1996, an ice core from about 320,000 years ago was successfully retrieved from an ice sheet near Dome Fuji Station. In 2007 an ice core from 720,000 years ago was retrieved. The air contained in them has been analyzed and the relationship between climate change and carbon dioxide levels is being studied. Penguin behavior research2011–Video loggers were attached to wild Adélie penguins in 2011, and their predatory activity was successfully filmed for the first time from the penguins’ perspective. Penguin migration was also successfully tracked with the use of a GPS logger and other devices.1. Observation of the ozone layer combines several methods: measuring ozone levels at different altitudes using small weather balloons, gauging the total volume of atmospheric ozone from the ground, and observing the ozone layer using satellites. Japan began ozone measurements in 1961. 2. Average total ozone volume in October 1979 and October 2016 (created by the Japan Meteorological Agency based on satellite data provided by the U.S. National Aeronautics and Space Administration [NASA]). The colors represent ozone thickness: the lower the color in the bar at right, the thinner the ozone layer. Though the ozone hole is tending to shrink gradually, a complete recovery will take some more time. Forecasts based on numerical models suggest that ozone volume will return to 1980 levels from the middle of the twenty-first century onward. 3. In 2007 an expedition team succeeded in drilling vertically into the ice sheet and retrieving a cylindrical ice core at Dome Fuji Station, about 1,000 kilometers (620 miles) inland from Syowa Station. Measuring roughly 12 centimeters (4.7 inches) in diameter and 3,000 meters (9,800 feet) in length, the column of ice has yielded valuable samples for understanding climate changes over the past 720,000 years. 4. There are four Japanese observation stations in Antarctica.Dr. Kazuyuki ShiraishiDirector-General, National Institute of Polar Research. Dr. Shiraishi is also professor of geology at the Graduate University for Advanced Studies (SOKENDAI) and is studying the geological history of the Antarctic continent. Since 2014, he has been chairman of the Council of Managers of National Antarctic Programs (COMNAP), which consists of 30 member countries.Dome Fuji StationMizuho StationSyowa StationAsuka StationSource: Japan Meteorological Agency maps of total ozone distribution as of October from 1979 through 2016 (http://www.data.jma.go.jp/gmd/env/ozonehp/link_hole_monthave.html) with the addition of dates and other text.© Yoshihiro Tomikawa, 54th Japanese Antarctic Research Expedition© National Institute of Polar Research1342Major achievements of Japan’s base for Antarctic observation