عنوان المقالة:دراسة تباين المعلمات الأيونية مع جغرافية للأرض وعدد البقع الشمسية STUDYING THE VARIATION OF IONOSPHEIC PARAMETERS WITH EARTH GEOGRAPHIC LATITUDES AND SUNSPOT NUMBER
Najat M. R. Al-Ubaidi, Hasanain H. A. Al-Dahlaki, Zina Fadel
الملخص الانجليزي
The monthly median critical frequency for ionospheric layers (foF2, foF1, and foE) variations were studied for different
latitudes for (12) months from years (2003-2010) started from moderate to low sunspot number (SSN). The data selected
from four ground ionosonde stations in Japan. From data analysis it reveal that all layers suffer great daily and seasonally
changes due to variation of (SSN) and geographic latitude. From results, it is seen that in the years of moderate (SSN) the value of (foF2) increases with decreasing latitude and the (foF2) peak shifted as latitude decreases. In the years of low (SSN), it is the same as in the years of moderate (SSN) but with one difference that the value of (foF2) is less for all months. About foF1and foE it reveals that as we reach equator the values of critical frequencies increases and decreases with increasing latitude this appears in winter and less in summer solstice and equinox. The maximum value for foF1 broaden from eight mornings till three afternoons, but foE reach approximately maximum in noon time for all months and
years chosen.