Report on the Activity of Commission G

(March 10, 2004)


1. Current status of facilities for ionospheric observation

--- MU radar new system

A new radar controller/receiver system for the MU radar was installed in February 2004. The system consists of 29-channel digital demodulators and digital modulator. Data acquisition rate is also improved drastically. The new system makes it possible to conduct radar-imaging experiment much more flexibly than before. We will soon develop a set of observation software, and start using the new system for further study of the atmosphere and ionosphere.


--- Airglow temperature photometers

Solar-Terrestrial Environment Laboratory, Nagoya University installed three airglow temperature photometers at Sata (31degrees North, 131degrees East), Rikubetsu (43degrees North, 144degrees East), and Koto Tabang (0degree South, 100degrees East) around December 2003 – March 2004. The photometers measure rotational temperatures of OH and O2 lines in the mesopause region. 


--- Ionosonde stations near the magnetic equator

FM/CW ionosonde was installed at Koto Tabang, Sumatra Island, Indonesia. This is one of the Southeast Asia Equatorial Ionospheric Network (SEALION) ionosondes. The others are at Chumphon, Chiang Mai, both in Thailand, and Bac Lieu, Vietnam. The Chumphon station is running after February, 2003, and the installation at the others are planed in April, 2004 (Chiang Mai) and August in 2004 (Bac Lieu). The first three stations lay at the longitude of 100 degrees East and Koto Tabang and Chiang Mai are the magnetic conjugated points. Chumphon and Bac Lieu are close to the magnetic equator. SEALION is a joint project among Communications Research Laboratory, Japan, King Mongkutfs Institute of Technology Ladkrabang, Thailand, Chiang Mai University, Thailand, National Institute of Aeronautics and Space, Indonesia, Hanoi Institute of Geophysics, Vietnam, and Kyoto University, Japan.


--- 4th and 5th HF Doppler observation stations

HF standard radio waves at 5 and 8 MHz are used for the study of ionospheric dynamics by measuring their Doppler shifts. 4th and 5th receivers were installed at Kyoto and Kashima, respectively. The transmitter is located at Chofu, Tokyo, and the other three receiving stations are Sugadaira, Kure, and Oarai. For detailed information, please visit the following web site,


2. Observation Campaigns

--- CPEA First International Observation Campaign in March-May 2004

"Coupling Processes in the Equatorial Atmosphere (CPEA)" is a research program funded by the Japanese Ministry of Education, Culture, Sports, Science and Technology (MEXT) as a Grant-in-Aid for Scientific Research on Priority Areas in the period from September 2001 until March 2007. CPEA studies dynamical coupling processes in the equatorial atmosphere by conducting various observations in the Indonesian equatorial region. The research activities are centered around the Equatorial Atmosphere Radar (EAR) located right at the equator in West Sumatra, Indonesia. Our counterpart in Indonesia for the EAR and CPEA is the National Institute of Aeronautics and Space (LAPAN) of Indonesia. The CPEA seeks to pioneer research on vertical couplings of the equatorial atmosphere. Two intensive observation periods are set as the international observation campaigns of the CPEA. The first CPEA campaign will be conducted in Indonesia from March to May 2004. (The second campaign is planned for 2005.) In the observation campaign, we operate several radars, a lidar, optical instruments and many other facilities around the EAR site. The CPEA campaign is endorsed by CAWSES (Climate and Weather of the Sun-Earth System) under SCOSTEP (The Scientific Committee On Solar-TErrestrial Physics). For more detailed information, please visit the following WEB page.


--- FERIX (F- and E-Region Ionosphere Coupling Study)

FERIX experiment is planned from May-September 2004 over Japan. Its main part is to conduct simultaneous observations of F-region and E-region ionospheric irregularities by means of the MU radar and the Lower-Thermosphere Profiler Radar (LTPR), respectively. The LTPR will be located at Sakata, Yamagata Prefecture), which will observe ionospheric E-region that is connected by the geomagnetic field to the F-region probed by the MU radar. Communications Research Laboratory (CRL) joins the program, and operates three FM/CW ionosondes at Sakata, Miyako, Miyagi Prefecture, Hirosaki, Aomori Prefecture. Simultaneous observations of airglow imagers and Fabry-Perot interferometers are also planned for the investigation of coupling processes between F- and E-regions and between ionosphere and neutral atmosphere.


3. Domestic Workshops

(1) 4th MU radar symposium was held at Radio Science Center for Space and Atmosphere (RASC), Kyoto University on December 2-3, 2003. Results of the MU radar observations and future plans were presented.

(2) 2nd Ionospheric Effect Symposium was held at the Communications Research Laboratory on December 17-18, 2003. The symposium was organaized by the national URSI-G Commission and 30 papers were presented. The major topics were ionospheric effects on the GPS applications and total electron contents.

(3) STE Event Report and Workshop was held at the Communications Research Laboratory on December 26, 2003. Outstanding geophysical phenomena related with the super storm in October-November, 2003 were discussed.

(4) Workshop on the dynamics of the upper atmosphere was held at Kagoshima on March 8-10, 2004.  This workshop was intended to produce publications from recent research activities related to the Aeronomy. 

(Prepared by T. Maruyama and M. Yamamoto)