History of research topics in SGO in ionospheric and magnetospheric research

Before end of 1950's:

• Magnetic variations
• Pulsations

Late 1950's and 1960's

• Ionospheric research
• Es-layers
• effects of nuclear explosions
• auroral D and E regions
• sunspot cycle variation in ionosphere radio aurora
• auroral X-rays
• absorption of cosmic radio noise
• auroral particle precipitation
• total electron content
• Micropulsations

1970's

• X-rays
• devewlopment of riometer and ionosonde techniques
• solar cycle variations
• seasonal and diurnal variations and anomalies of absorption
• extensive Es-layer studies
• auroral absorption substorm
• gravity waves anf F-layer
• special absorption events
• geomagnetic pulsations ands absorption

1980's

• EISCAT development, measurement, observations, analysis
• theoretical: formation of Es
• IPDP pulsdations
• ELF radio signals
• solar and magnetic cycles
• Polar Cap Absorption events
• high resolutiopn observations by EISCAT
• participation in large international campaigns

1990's

• Ion chemistry modeling
• applications of Statistical inversion theory
• satellite radio tompography, optocal tomography
• PCA-events
• heating experiments
• morphology of lower ionosphere
• small scale structure of riometer absorption (IRIS)
• long term trends
• PCA events
• solar wind by EISCAT
• VLF emissions
• man made VLF
• heater induced VLF
• substorms and VLF
• ionospheric Alfvén resonator
• morphology of short period pulsations
• GUISDAP development