. 2016;8(3):77-89.
In this study, a statistical analysis between three solar activity indices (SAI) namely; sunspot number (ssn), F10.7
index (sf) and Mg II index (mg) and total column ozone (TCO) time series over three cities in Kenya namely;
Nairobi (1.17º S; 36.46º E), Kisumu (0.03º S; 34.45º E) and Mombasa (4.02º S; 39.43º E) for the period 1985 -
2011 are considered. Pearson and cross correlations, linear and multiple regression analyses are performed. All
the statistical analyses are based on 95% confidence level. SAI show decreasing trend at significant levels with
highest decrease in international sunspot number and least in Mg II index. TCO are highly correlated with each
other at (0.936< r < 0.955, p < 0.001). SAI are also highly correlated with each other at (0.941< r < 0.976, p <
0.001) and are significantly positively correlated with TCO over the study period except Mg II index at Kisumu.
TCO and SAI have correlations at both long and short lags. At all the cities, F10.7 index has an immediate
impact and Mg II index has a delayed impact on TCO. A linear relationship exists between the two variables in
all the cities. An increase in TCO of about 2 – 3 % (Nairobi), 1 – 2% (Kisumu) and 3 – 4 % (Mombasa) is
attributed to solar activity indices. The multiple correlation coefficients and significant levels obtained show that 3
– 5% of the TCO at Nairobi, Kisumu and Mombasa can be predicted by the SAI.
Keywords: correlation, F10.7 index, Mg II index, regression, solar activity indices, sunspot number, time series,
total column ozone