142-147Effect of the eastward and northward components of IMF (By and Bz) on the daytime E-region and nighttime F-region drifts at Patiala, which is situated near the Sq focus , has been studied. Drift records pertaining to the year 1987-88 have been used. The E-region drift speed decreases with increase in B in winter while it increases during summer and equinoxes. It is opposite in the F-region. Significant increase of westward drift with Bz is seen in the E- and F-regions where the correlation coefficients are -0.90 and -0.70 respectively. The southward component of the E-region drift decreases significantly with increase in Bz or By. With increase in By the drift speed in the E-region decreases while it increases in the F-region. The westward components of both the E- and F-region drifts show an increase with an increase in By
