By means of the GASCOD spectrometer at Stara Zagora station (42.8 N, 26.1 E), data series were obtained of monthly NO2am (at sunrise) and NO2pm (at sunset) slant column densities (SCD), covering the interval from September 1999 to the end of 2006. After removing the seasonal cycle, relationships between the NO2am and F10.7 solar flux and NO2pm and F10.7 were sought. The monthly deseasonalized NO2am show a positive statistical significant correlation with F10.7 having r = 0.41 at level p = 0.01. No statistical significant correlations were found between monthly NO2pm and F10.7 unless the QBO phase was taken into consideration. The original data series of the quasi-biennial oscillations (QBO) at the level of 30 h Pa have been used to study the relation between the NO2 and the F10.7 taking into account the QBO phase. The data have been separated into two different groups - positive (westerly) and negative (easterly) QBO phase. As a result, during the negative QBO phase, the monthly NO2pm show a negative correlation with F10.7 (r = - 0.37 and p = 0.01). During the positive QBO phase, the monthly NO2pm show no correlation with F10.7 (r = 0.02). The separation of NO2am into two groups according to the sign of the QBO phase practically does not change the results - the correlation coefficient remains between 0.40 and 0.43 at level p = 0.01. The statistical significance of the found relationships was determined by means of Student's t-test.
Statistical relationship of the NO2 slant column densities over Stara Zagora station and the solar F10.7 flux with consideration of the QBO phase
FRavegnani;
2008
Abstract
By means of the GASCOD spectrometer at Stara Zagora station (42.8 N, 26.1 E), data series were obtained of monthly NO2am (at sunrise) and NO2pm (at sunset) slant column densities (SCD), covering the interval from September 1999 to the end of 2006. After removing the seasonal cycle, relationships between the NO2am and F10.7 solar flux and NO2pm and F10.7 were sought. The monthly deseasonalized NO2am show a positive statistical significant correlation with F10.7 having r = 0.41 at level p = 0.01. No statistical significant correlations were found between monthly NO2pm and F10.7 unless the QBO phase was taken into consideration. The original data series of the quasi-biennial oscillations (QBO) at the level of 30 h Pa have been used to study the relation between the NO2 and the F10.7 taking into account the QBO phase. The data have been separated into two different groups - positive (westerly) and negative (easterly) QBO phase. As a result, during the negative QBO phase, the monthly NO2pm show a negative correlation with F10.7 (r = - 0.37 and p = 0.01). During the positive QBO phase, the monthly NO2pm show no correlation with F10.7 (r = 0.02). The separation of NO2am into two groups according to the sign of the QBO phase practically does not change the results - the correlation coefficient remains between 0.40 and 0.43 at level p = 0.01. The statistical significance of the found relationships was determined by means of Student's t-test.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
