New Ages of Operational Space Weather Forecast in Japan

Abstract

The origin of Japanese space weather forecast comes from the forecast of radio wave broadcasts which provide current and future conditions of radio wave propagation for telecommunications. The Japanese radio wave forecast service began in the 1940s. To improve the reliability of long-distance telecommunications by radio waves, the subject "solar activity effect to the ionosphere" was extensively studied in the 1950s. During these research activities, the relationships between radio propagation and solar microwave bursts and sudden ionospheric disturbance were examined. Further, polar cap absorption events were studied and their relationships with type IV solar radio bursts were discovered. Present-day space weather research and operations in Japan originated from this positive interaction between basic research and practical needs in this earlier era [Nishida, 2010].With the passage of time, the importance of radio wave communications has decreased due to the establishment of the wired-communication network. In contrast, activities of space research and development are continuing to grow in Japan based on our nation's rocket and satellite technologies. Because of this historical background of radio wave forecasting beginning in the 1940s, it can be stated that the world's first "space weather" forecast program was started in 1988 by the Communications Research Laboratory (currently, the National Institute of Information and Communications Technology (NICT)) [Marubashi, 1989]. Forecasting Operation and Information ServicesJapanese operational space weather forecast is currently provided from the Space Weather and Environment Informatics Laboratory in NICT. Since NICT's space weather forecast center belongs to the International Space Environment Service as the Regional Warning Center Japan, our operational activities are supported by international cooperation. Solar flare, geomagnetic activity, highenergy particles (proton event and relativistic electrons in the radiation belts), and conditions of radio wave propagation are predicted based on the analysis of current conditions and trends of space weather activities. A forecaster's meeting is held from 14:30 JST (05:30 UT) each day for discussing the final decision of the current day's space weather forecast (Figure 1). The latest data and simulation/model outputs ranging from the Sun to Earth's upper atmosphere are consulted.Information service is one of the key elements of space weather forecasting in the NICT, because forecasting activities should be widely provided to the public. Forecasting information and an online database of space weather monitoring were provided via computer network before the internet era. NICT also attempts to provide new types of forecasting information for citizens who are not familiar with space weather itself. NICT has made a short movie to explain the technical terms of space weather (Figure 1). This type of information, with many images, is very useful for nontechnical people to understand space weather forecasts.Major users of NIC...

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