14:45 〜 15:00
[PEM13-11] SuperDARN SENSU Syowa radars project -future perspective-
キーワード：SuperDARN、短波レーダー、宇宙天気、超高層大気、電離圏、中間圏
SuperDARN (Super Dual Auroral Radar Network) is an international high-frequency coherent radar network established in 1995. More than 35 radars are currently operated by more than 15 research institutes in about 10 countries, distributed from middle to high latitudes in both hemispheres. One of the original scientific goals of the network was to obtain real-time global plasma convection and electric field potential maps, which had never been done before, to contribute primarily to space weather research. The radar network can also address many aspects of scientific questions on the global upper atmosphere including ionised and neutral populations and their coupling, the influence of geospace on lower atmosphere and possibly global climate change, plasma physics, and practical applications including space weather nowcast/forecast. NIPR has joined the project since its establishment in 1995 and has been running 2 SENSU SuperDARN radars, Syowa South and Syowa East radars, in Antarctic Syowa station (69.00 S, 39.58 E) in the polar auroral zone. Both radars have substantially contributed to the international project, e.g., studies on auroral phenomena and storms/substorms, geomagnetic pulsations, precise neutral wind measurement around the mesopause region, polar mesospheric summer echoes (PMSEs), magnetosphere-ionosphere-neutral atmosphere vertical coupling, and influence of low solar activity or grand minimum on space weather.
Long-term planning of the next Phase X 6-year Japanese Antarctic Research Expedition (JARE) project (2022-2028) started practically about one and a half years ago, especially on Prioritised Research Projects and long-term monitoring observation. We proposed a SuperDARN observation plan as one of the key components contributing mainly to the new space weather / space climate research project proposed by Kataoka et al. (which is expected to be approved as one of the phase X JARE prioritised research projects by the Japanese government in June, 2021). Their proposal is to reveal the impact of high energy particles on the Earth’s atmosphere with cosmic ray observations and new spectral riometers, etc., and also to understand the geospace environment quantitatively under a lower solar activity where polar cap region observations, such as optical imager networks in Antarctica, are essential for understanding and predicting geospace under the latest lower solar activity condition after about a half-century long high solar activity period in collaboration with theoretical and simulation studies. In the proposal, SuperDARN contributes to the research by providing the global ionospheric condition.
We have devoted much time to new space weather and upper atmosphere research with SuperDARN, and our international community has published several tens of cutting-edge scientific papers every year since the 1990s. Moreover, “Space weather maps” - global ionospheric convection and electrical potential maps - with high temporal resolution (of about 1 to 2 mins typically) obtained from the international network data (in quasi-real time) have been widely utilised for a variety of space weather research and prediction works. The number of papers citing SuperDARN has also almost monotonically increased and exceeded more than 1000 papers per year recently (meaning h-index of SuperDARN as a community is more than 40). The number of research groups, HF radars joining SuperDARN and its total fields-of-view covering the upper atmosphere has also grown. Hence this basic data obtained by SuperDARN has been increasingly important in the modern upper atmosphere research and it is therefore of great importance to keep this observation going on a long-term basis and to provide those valuable and fundamental data to the community. Taking into account these two aspects of this observational research, we have concluded that we should maintain and even accelerate SuperDARN as an essential long-term scientific monitoring observational research from the upcoming phase X JARE project for long-term stable contribution to broader coverage of research and applications, which can also contribute to the prioritised research project on space weather and space climate research. We plan to upgrade the current conventional log-periodic antenna arrays, which require laborious maintenance with human and financial resources, to mostly maintenance-free wire-type log-periodic antenna arrays. In addition, the old transmitters will also be upgraded to new stable transmitters for long-term stable operation in close engineering and technical collaboration with NICT and Nagoya Univ./ISEE groups.
Long-term planning of the next Phase X 6-year Japanese Antarctic Research Expedition (JARE) project (2022-2028) started practically about one and a half years ago, especially on Prioritised Research Projects and long-term monitoring observation. We proposed a SuperDARN observation plan as one of the key components contributing mainly to the new space weather / space climate research project proposed by Kataoka et al. (which is expected to be approved as one of the phase X JARE prioritised research projects by the Japanese government in June, 2021). Their proposal is to reveal the impact of high energy particles on the Earth’s atmosphere with cosmic ray observations and new spectral riometers, etc., and also to understand the geospace environment quantitatively under a lower solar activity where polar cap region observations, such as optical imager networks in Antarctica, are essential for understanding and predicting geospace under the latest lower solar activity condition after about a half-century long high solar activity period in collaboration with theoretical and simulation studies. In the proposal, SuperDARN contributes to the research by providing the global ionospheric condition.
We have devoted much time to new space weather and upper atmosphere research with SuperDARN, and our international community has published several tens of cutting-edge scientific papers every year since the 1990s. Moreover, “Space weather maps” - global ionospheric convection and electrical potential maps - with high temporal resolution (of about 1 to 2 mins typically) obtained from the international network data (in quasi-real time) have been widely utilised for a variety of space weather research and prediction works. The number of papers citing SuperDARN has also almost monotonically increased and exceeded more than 1000 papers per year recently (meaning h-index of SuperDARN as a community is more than 40). The number of research groups, HF radars joining SuperDARN and its total fields-of-view covering the upper atmosphere has also grown. Hence this basic data obtained by SuperDARN has been increasingly important in the modern upper atmosphere research and it is therefore of great importance to keep this observation going on a long-term basis and to provide those valuable and fundamental data to the community. Taking into account these two aspects of this observational research, we have concluded that we should maintain and even accelerate SuperDARN as an essential long-term scientific monitoring observational research from the upcoming phase X JARE project for long-term stable contribution to broader coverage of research and applications, which can also contribute to the prioritised research project on space weather and space climate research. We plan to upgrade the current conventional log-periodic antenna arrays, which require laborious maintenance with human and financial resources, to mostly maintenance-free wire-type log-periodic antenna arrays. In addition, the old transmitters will also be upgraded to new stable transmitters for long-term stable operation in close engineering and technical collaboration with NICT and Nagoya Univ./ISEE groups.