Geomagnetic Observatories, Surveys and Analyses : IAGA Division V

Dr. Masahito Nosé is the Division Chair for Division V : Geomagnetic Observatories, Surveys and Analyses. Here, he answers some of our questions about himself and his division. 

1) Could you please tell us something about yourself?

I am Dr. Masahito Nosé, working for Institute for Space-Earth Environmental Research, Nagoya University, Japan. I earned Ph.D. in 1998 and had jobs at Applied Physics Laboratory, Johns Hopkins University, USA for 1998–2001 and at World Data Center for Geomagnetism, Kyoto/Graduate School of Science, Kyoto University, Japan for 2001–2018. My research interests include geomagnetic field variations, geomagnetic indices, energetic particle acceleration, plasma ion composition, and ring current dynamics. Recent topic is development of low-cost magnetometer with magneto-impedance sensor, which make it possible to deploy a dense ground observation network.

2) What are the basic research questions of the IAGA division you head? 

IAGA Division V, Geomagnetic Observatories, Surveys and Analyses, has objectives to promote high quality standards in geomagnetic data acquisition, observatory and survey procedures, geomagnetic indices, and data dissemination; to analyse magnetic observation data for the purposes of understanding the various sources of the magnetic field. In this respect, the following three working groups are active: Working Group V-OBS: Geomagnetic Observation; Working Group V-MOD: Geomagnetic Field Modeling; and Working Group V-DAT: Geomagnetic Data and Indices.

 

Location of geomagnetic observatories in operation. Image from BGS.

3) What are the past important results of this division? 

Working Group (WG) V-OBS maintains a list of observatories operating worldwide now and in the past, and allocates IAGA codes. WG is also responsible for the organisation of a workshop on geomagnetic observatory instruments, data acquisition and processing every two years. These efforts keep quality for measurements and for data processing. Two IAGA Guides related to geomagnetic observations have been published: “IAGA Guide for Magnetic Measurements and Observatory Practice” by J. Jankowski and C. Sucksdorff in 1996 and “IAGA Guide for Magnetic Repeat Station Surveys” by L.R. Newitt, C.E. Barton, and J. Bitterly in 1997.

Working Group V-MOD released the 13th Generation International Geomagnetic Reference Field (IGRF-13) in December 2019. The IGRF model is widely used not only in research community but also in ordinary society. This is the outcome of enduring efforts of this working group and continuous observations of geomagnetic field on ground and by satellites.

Earth's magnetic structure. Image from NOAA NCEI.

Working Group V-DAT has been supporting derivation of geomagnetic indices and event lists such as aa index, am index, Kp index, Disturbance storm-time (Dst) index, Auroral Electrojet (AE) index, Polar Cap (PC) index, SSC (storm sudden commencement) and SFE (solar flare effect), and Q-Days and D-Days. These indices and event list are inevitable for research in space physics and space weather. This working group also designed the geomagnetic field data dissemination format called IAGA2002 format, which is now used as standard in data exchange.

4) What do you think would be the future applications or impacts through this research?

Continuous activity of Division V is essential to keep precise geomagnetic observations and products depending on them, for example, IAGA-endorsed geomagnetic indices, event list, and IGRF model. High-quality geomagnetic field data and geomagnetic indices can be applied to space weather forecast and geomagnetically induced current research.