QBO'nun iyonküre üzeri?ndeki? etki?si?

The Effect over the Ionosphere of the QBO (Quasi Biennial Oscillation) In this study, the relationship between F2 region critical frequency (foF2) and the Quasi Biennial Oscillation (QBO) occurring easterly- westerly direction in the equatorial stratosphere is analyzed statically. In theoretical part of the study, oscillations occurring in the stratosphere and processes of these oscillations transportation to the upper regions where mesosphere lower thermosphere and the parameters that effected in this process is defined. In the statically analysis of the study, firstly the relationship between foF2 and QBO is investigated by using scatter diagram. In obtained results, is observed that there is linear relationship between foF2 and QBO and it varies depending on years and geographic locations. Secondly the relationship between foF2 and QBO is investigated with correlation coefficient method. While maximum correlation coefficient between QBO measured in level 70 hPa and foF2 is positive in the north latitude, it is only positive between 5? S ile 10? S in the south latitude. The results for 10 hPa are quite different from the results for 70 hPa. The correlation coefficient between QBO and foF2 for 10 hPa has positive relation in the equator to latitudes 5 N and 10 N. The coefficient has also negative relation in the equator to latitudes 15? N and 20? N. It is oppositely observed in the southern hemisphere. The time series analysis method which define long term relationship between two variables is used to expose the analysis of statically relationship between stratospheric QBO and the foF2. While analyzing, GLS which is effective parameter on the foF2 critical frequency is also developed multi regression model by including to method. In the analysis results it is observed that the variations in the foF2 are affected in rate approximately 70 % and 80 % from the GLS and QBO values. Together with to show the differences between geographic locations, it is observed that these variations can be explained up to rate approximately 60 % and 80 % by GLS and GLS2 in the models. At the same time, it is understood that may be explained by the QBO up to the rate 2 %-14 % of these changes. The results obtained by the statistical models which used to the study show positively and negatively be affected in rate 2 %- 14 % from the QBO together with to show the differences between geographic locations of the critical frequency foF2 of the ionosphere in the equatorial zone. Keyword: Ionosphere, Critical Frequency, QBO, Sun Spot Number, Long-Term Multiple Regression