Solar activity dependence of Sq field observed at Biak station.

This paper show our preliminary results on solar acitivty effect to the low-latitude Sq field. We analyzed one solar cycle of geomagnetic data observed at Biak station Indonesia during 1992-2004 to show the dependence of Sq field amplitude to solar activity. In this paper, the monthly sunspot number has been used to represent the solar activity. We found that the amplitude of Sq field following the trend of sunspot number. Also, we analyzed the seasonal variation of Sq field and found that the amplitude of Sq field during equinoxes are larger than solstices. This results show that low latitude Sq field are influenced by the solar radiation. [ABSTRACT FROM AUTHOR]