YÜKSEK ENLEM foF2 DEĞERLERİNDEKİ DEĞİŞİMLERİN JEOMANYETİK AKTİVİTEYE BAĞLILIĞI

Yıl 2017, Cilt: 5 Sayı: 2, 138 - 147, 31.10.2017

Kerime Aksaç İbrahim Ünal Erdinç Timoçin

https://doi.org/10.20290/aubtdb.304375

Öz

Bu çalışmada, Aralık 1971-Eylül 1972 tarihleri arasında yüksek enlem bölgesi olarak tanımlanan 60^o-90^o
değişmeyen manyetik enlem arasındaki 7 iyonsonda istasyonundan alınan saatlik
foF2 verilerinin değişmeyen manyetik enleme göre
değişimleri, farklı jeomanyetik aktivite durumları için incelenmiştir.
Analizlerden elde edilen sonuçlara göre, gündüz saatlerindeki foF2
değerlerinin, gece saatlerindeki değerlerden büyük olduğu, ayrıca bu saatlerde
foF2 değerlerinin değişmeyen manyetik enlem artışı ile
68^o-72^o değişmeyen manyetik enlemleri arasındaki artış
dışında azaldığı tespit edilmiştir. Gece saatlerinde ise foF2
değerlerinin yaklaşık 66^o-72^o değişmeyen manyetik enlemleri arasında arttığı, bu enlemlerden daha
büyük ve daha küçük enlemlerde ise foF2 değerlerinin azalarak çukura benzer bir yapı oluşturduğu gözlemlenmiştir. Ayrıca
mevsimsel ve jeomanyetik aktivite değişimlerinin, foF2 değerlerinin
enlemsel değişimleri üzerinde önemli bir etkiye sahip olduğu tespit edilmiştir.
Jeomanyetik pasif durumdaki foF2 değerleri, jeomanyetik aktif durumdaki foF2
değerlerinden büyüktür. Özellikle jeomanyetik aktif durumdaki Aralık döneminde,
polar cap ve polar oval bölgeleri daha belirgin ve bu bölgeler enlemsel olarak
daha geniş bir yapıya sahiptir.

Anahtar Kelimeler

Yüksek enlem iyonosferi, Manyetosfer, Jeomanyetik aktivite

THE DEPENDENCE ON THE GEOMAGNETIC ACTIVITY OF CHANGES IN THE foF2 VALUES AT THE HIGH LATITUDES

Öz

In this study, changes according to invariant magnetic latitude of the
hourly foF2 data that are taken from seven ionosondes stations are situated at
between 60^o-90^o invariant magnetic latitude as known high
latitude region are investigated for different geomagnetic activity conditions
during December 1971-September 1972. According to the results obtained from the
analyzes, it was found that the foF2 values in the daytime are larger than
those in the nighttime, and the foF2 values in these hours decreases with the
increasing of the invariant magnetic latitude the except for between about 68^o
and 72^o invariant magnetic latitude. At night time, it was observed
that the foF2 values increases between about 66^o and 72^o invariant
magnetic latitude, while the foF2 values exhibit a trough structure at larger
and smaller latitudes than these latitudes. It is also observed that seasonal
and geomagnetic activity changes have a significant influence on the
latitudinal changes of the foF2 values. The foF2 values in the geomagnetic
quiet condition are larger than the foF2 values in the geomagnetic active
conduction. Especially in the geomagnetic active conduction of the December,
the polar cap and polar oval zones are more prominent and have a larger
latitudinal structure.

Anahtar Kelimeler

High latitude ionosphere, Magnetosphere, Polar region, Geomagnetic activity

Kaynakça

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