1.Name of Database: Kakioka One-second Resolution Geomagnetic Data 2. Institution: (1) Kakioka Magnetic Observatory, Japan Meteorological Agency (2) WDC for Geomagnetism, Kyoto 3. Contents of Database: This database contains the one second resolution geomagnetic field data observed at Kakioka Magnetic Observatory located at (Geographic Latitude, Geographic Longitude) = (36.23, 140.19). The data have been supplied to the World Data Center C2 for Geomagnetism, Kyoto for public use. The latest data are available from the data center through WWW on-line service (http://swdcdb.kugi.kyoto-u.ac.jp). Three magnetic components (H, Z and D) are measured by the fluxgate magnetometer every second with 0.01nT resolution. The values are derived using provisional base line values. For more information, please refer "Report of the Kakioka Magnetic Observatory". The data are written with 2-byte binary integer usually used in the UNIX system on most work stations. We need to exchange the order of the two (i.e., upper and lower) bytes when we use the data with PCs (i.e., DOS, LINUX, WINDOWS etc.). 5. Contact: (1) Kakioka Magnetic Observatory, Japan Meteorological Agency Kakioka 595, Yasato-machi, Niihari-gun, Ibaraki-ken 315-0116, Japan (2) Data Analysis Center for Geomagnetism and Space Magnetism, Graduate School of Science, Kyoto University, Kyoto 606-8501, Japan 6. Public Offering of Database: When you publish the results by using the data , please acknowledge to the Kakioka Magnetic Observatory.