Pola Variasi Reguler Medan Magnet Bumi Di Tondano - Prasetyo, Teguh; Tanauma, Adey; ., As'ari (Sam Ratulangi University, 2014)
Data variasi medan magnet bumi komponen horisontal diambil dari komputer akuisisi yang merekam data secara real time. Dibuat grafik data magnet bumi komponen horisontal versus waktu per hari. Dipilih grafik quite days dan dibandingkan dengan quiet days di Lerwick (Inggris). Dihitung nilai rata-rata dari Quiet days yang sama perbulan untuk dijadikan pola variasi reguler bulanan, sehingga dalam satu tahun dapat dibuat dua belas pola variasi reguler medan magnet bumi. Hasilnya menunjukkan bahwa variasi reguler medan magnet bumi polanya teratur, nilai variasi tertinggi berkisar 39308,3– 39409,5 nT pada kisaran waktu 02:39–03:38 Universal Time. Pola variasi reguler medan magnet bumi digunakan sebagai acuan untuk menganalisis variasi harian medan magnet bumi. Pada tahun 2011 tercatat badai besar geomagnet sebanyak 11 kali yang nilai variasinya berkisar 71–20 nT dengan nilai K indeks sama dengan lima.Data variation of the horizontal component of the earth's magnetic field was taken from the acquisition computer which records data in real time. Graphs describing the horizontal component data versus time were created daily. Graphs of quiet days were selected and compared with quiet days in Lerwick (England). Average value the same of quiet days were calculated in order to create monthly regular variation pattern, so that in one year there were twelve regular variation patterns of the earth 's magnetic field created. The results showed that the regular variations of the earth 's magnetic field is on a regular pattern, the value of the highest variation ranged 39308.3-39409.5 nT at around 2:39 to 3:38 Universal Time. Regular variation patterns of the earth 's magnetic field were used as references for analyzing the daily variation of the earth 's magnetic field. In 2011, the large geomagnetic storms were recorded 11 times, the value of the variation range 71–20 nT with the K index value equal to five.